Biochemical and Biophysical Research Communications

Screening of potential targets and small-molecule drugs related to lipid metabolism in ovarian cancer based on bioinformatics

about 70 % of ovarian cancer (OC) patients with postoperative chemotherapy relapse within 2-3 years due to drug resistance and metastasis, and the 5-year survival rate is only about 30 %. Lipid metabolism plays an important role in OC. We try to explore the potential targets and drugs related to lipid metabolism to provide clues for the treatment of OC. the gene expression profiles of OC and normal ovarian tissue samples were obtained from the cancer genome atlas (TCGA) and genotype-tissue expression databases (GTEx). The differentially expressed genes (DEGs) were analyzed. Lipid metabolism related genes (LMRGs) were downloaded from MSigDB database. The DEGs related to lipid metabolism in OC was obtained by intersection. And gene ontology (GO) and kyoto encyclopedia of genes and genomes (KEGG) analyses were performed. The protein-protein interaction (PPI) network of lipid metabolism related DEGs was constructed, and seven algorithms were used to screen core potential target genes. Its expression in OC and prognostic ability were analyzed by Univariate Cox. Cmap database mining OC lipid metabolism related potential small-molecular drugs and docking. CCK8, scratch assay, transwell test and free fatty acid (FFA) assay, fluorescence detection of cellular fatty acid uptake, and the reactivity assay of CPT1A were used to detect the biological effects of drugs on OC cell.Rreverse transcription PCR(RT-qPCR) and WesternBlot were performed to measure the expression of core targets. 437 DEGs related to lipid metabolism of OC were screened. GO and KEGG analysis showed that these DEGs were lipid metabolism, fatty acid metabolism, sphingolipid metabolism, PPAR signal pathway and so on. The PPI network based on lipid metabolism DEGs consists of 301 nodes and 1107 interaction pairs, and 6 core target genes were screened. ROC curve analysis showed that all of the 6 genes could predict the prognosis of OC. Three small molecular drugs Cephaeline, AZD8055 and GSK-1059615 were found by cmap and molecular docking showed that they all had good binding ability to target gene. Cephaeline has the strongest inhibitory effect on SKOV3 cells of OC, and could significantly inhibit cell migration and invasion regulate the mRNA and protein expression of some targets, and inhibit lipid metabolism process in ovarian cancer cells. six OC potential genes related to lipid metabolism were identified and verified, which can be used as potential biomarkers and therapeutic targets to evaluate the prognostic risk of OC patients. In addition, three small-molecular drugs that may be effective in the treatment of OC were unearthed, among which Cephaeline has the most potential. We speculate that Cephaeline may target six genes to inhibit progression of OC by affecting lipid metabolism.

Genomic insights and therapeutic efficacy of PARP inhibitors in a high-LOH patient-derived xenograft from malignant transformation of ovarian teratoma

The malignant transformation of ovarian mature cystic teratoma (MTMCT) is a rare and aggressive condition often diagnosed at advanced stages with limited treatment options. Leveraging cancer genomic profiling (CGP), this study evaluated the efficacy of poly(ADP-ribose) polymerase (PARP) inhibitors in a patient-derived xenograft (PDX) model of MTMCT with high loss of heterozygosity (LOH). Tumor samples from a patient with MTMCT were used to establish the PDX model. CGP revealed high LOH and actionable mutations, including STK11 (E256*) and EMSY amplification, suggesting potential sensitivity to PARP inhibitors. Mice treated with PARP inhibitors exhibited significantly reduced tumor volumes compared to controls. Whole-exome sequencing (WES) performed on control and post-treatment residual tumors demonstrated that while total LOH levels remained stable, copy-neutral LOH (CN-LOH) increased significantly, indicating treatment-induced genomic instability. Notably, STK11 (E256*) underwent CN-LOH in residual tumors, suggesting a role in acquired resistance. Furthermore, EMSY amplification, initially observed in the tumor and associated with PARP inhibitor sensitivity, was absent after treatment, reflecting clonal selection or adaptive resistance. These findings underscore the therapeutic potential of PARP inhibitors in high-LOH MTMCT while highlighting the emergence of resistance mechanisms, including CN-LOH and loss of EMSY amplification. They emphasize the importance of considering tumor evolution and treatment timing when interpreting CGP results, providing a foundation for further research into predictive biomarkers and resistance mechanisms in rare gynecologic malignancies.

Significance of PFKFB4 and gene risk signature in cervical cancer prognosis and progression

Cervical cancer (CC) ranks among the most prevalent malignant gynecological neoplasms. Given the significant challenges in treating and detecting CC at an early stage, this study aims to identify key biomarkers associated with the prognosis and progression of this malignancy. Mendelian randomization (MR), expression quantitative trait locus (eQTL) data, survival assessments, and differential expression analyses were used to identify potential biomarkers. Based on the expression profiles of the identified genes, a risk signature was developed. The correlation between gene expression levels and the clinical characteristics of CC patients was also examined. Additionally, qRT-PCR, Transwell migration, and wound healing assays were conducted to validate the reliability of PFKFB4 expression, as well as cellular migration and invasion capabilities. The genes PFKFB4, SFXN3, and ITGB2 were identified as critical targets for CC. MR analysis revealed that ITGB2 and PFKFB4 exhibited a negative correlation with CC development, whereas SFXN3 demonstrated a positive association with the disease. Mechanistic investigations highlighted a strong link between these genes and the immune microenvironment. The developed risk signature displayed significant correlations with the prognosis, metastatic stages, and histological classifications of CC patients. Furthermore, the expression level of PFKFB4 was significantly associated with the T and M stages in CC patients. Notably, PFKFB4 was significantly overexpressed in cervical cancer cells and tissue samples, and its silencing markedly inhibited cell migration and invasion. In summary, this study elucidates the molecular mechanisms underlying CC progression and identifies potential candidate biomarkers that could inform treatment strategies for this malignancy.

USP31 confers radio-resistance in cervical cancer cells via ferroptosis pathway by deubiquitinating and stabilizing GPX4

Ubiquitin-specific peptidase 31 (USP31), a member of the deubiquitinating enzyme family, linked to the pathogenesis of cervical cancer (CC). Despite this association, the precise mechanisms underlying its role remain inadequately understood. Recent studies have identified ferroptosis as a potential mechanism contributing to radiotherapy-mediated tumor suppression and the development of radioresistance. Consequently, this research seeks to inspect the regulatory effect of USP31 in the radioresistance of CC cells, with particular emphasis on the ferroptosis pathway. Our findings indicate that USP31 levels increase in human CC cells after radiation exposure. The knockdown of USP31 through transfection with si-USP31 significantly enhanced the radiosensitivity of SiHa and HeLa cells. This knockdown also promoted ferroptosis, as evidenced by enhanced lipid reactive oxygen species (ROS) generation, higher endocellular Fe

An integrated approach of transcriptomics, network pharmacology and molecular docking uncovers the mechanisms of 5,6,7,4′-tetramethoxyflavone in treating cervical cancer

5,6,7,4'-tetramethoxyflavone (TMF), a dietary polymethoxyflavone (PMF) with multifaceted health-promoting benefits, has recently been identified as a potential chemotherapeutic agent for cervical cancer (CCA) in our previous study. Nevertheless, its mechanisms of action involved remain unclear. To address this knowledge gap, we employed an integrative strategy combining transcriptomic profiling, network pharmacology, and molecular docking to systematically investigate TMF's inhibitory effects on HeLa cells. Transcriptomic analysis revealed 1,127 differentially expressed genes (DEGs) in TMF-treated HeLa cells, comprising 765 down-regulated and 362 up-regulated genes. Protein-protein interaction (PPI) network analysis identified 12 hub targets ranked by connectivity: JUN, FN1, VEGFA, FOS, ITGB3, NOTCH1, ESR1, EGF, APP, DLG4, EGR1 and ITGB2. Gene Ontology (GO) enrichment analysis demonstrated significant associations with biological processes including signal transduction, cytoplasm, protein binding, positive regulation of apoptotic cell clearance, t-tubules and extracellular matrix structural constituent conferring tensile strength. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed enrichment in 38 signaling pathways. Molecular docking simulations comfirmed good affinities between TMF and all 12 targets, exhibiting binding energies below -5.0 kcal/mol. Our findings suggest that TMF exerts antitumor activity against HeLa cells through multi-target modulation of critical pathways including Pathway in cancer, FoxO, PI3K-Akt, mTOR, AMPK and apoptosis signaling pathway. While these bioinformatics predictions provide mechanistic insights, experimental validation through q-PCR, western blotting, and surface plasmon resonance remains essential to confirm these findings. This study establishes a foundation for further exploration of TMF's therapeutic potential in CCA management.

METTL3-mediated m6A methylation of SLC38A1 stimulates cervical cancer growth

The objective of this study was to better characterize the role of the glutamine transporter SLC38A1 in cervical cancer and explore the underlying mechanisms. Data from public databases and clinical cervical cancer tissue samples were used to assess the expression of SLC38A1 and its prognostic significance. Immunohistochemical staining, qRT-PCR, and Western blotting were used to evaluate the expression of relevant genes and proteins. Cell viability, cell cycle, apoptosis, and intracellular glutamine content were measured using CCK-8, flow cytometry, and biochemical assays. Additionally, the RNA immunoprecipitation (RIP) assay was used to examine the impact of METTL3/IGF2BP3 on the m

LncRNA ASB16-AS1 accelerates cellular process and chemoresistance of ovarian cancer cells by regulating GOLM1 expression via targeting miR-3918

Reportedly, ovarian cancer (OC) is a major threat to women's health. Long non-coding RNA (lncRNA) ASB16-AS1 has been uncovered to participate in cancer progression. Nevertheless, the role of ASB16-AS1 in OC remains to be revealed. This study aimed to unveil the biological function of ASB16-AS1 and its underlying mechanisms in OC cells. QRT-PCR was done to test ASB16-AS1 expression in OC cells. Functional assays were performed to evaluate the malignant behaviors and cisplatin resistance of OC cells. Mechanistic analyses were done to investigate the regulatory molecular mechanism in OC cells. ASB16-AS1 was found to be highly expressed in OC cells. ASB16-AS1 knockdown repressed proliferation, migration, and invasion of OC cells, while facilitating cell apoptosis. ASB16-AS1 was further validated to up-regulate GOLM1 through competitively binding with miR-3918. Moreover, miR-3918 overexpression was corroborated to suppress OC cell growth. Rescue assays further uncovered that ASB16-AS1 modulated the malignant processes of OC cells via targeting miR-3918/GOLM1 axis. ASB16-AS1 facilitates the malignant processes and chemoresistance of OC cells via serving as miR-3918 sponge and positively modulating GOLM1 expression.

Tripterygium glycosides reverse chemotherapy resistance in ovarian cancer by targeting the NRF2/GPX4 signal axis to induce ferroptosis of drug-resistant human epithelial ovarian cancer cells

Cisplatin resistance is the main cause of postoperative recurrence and difficulty in the treatment of ovarian cancer. It is urgently needed to identify therapeutic drugs with unique functions to overcome the current challenges in the treatment of ovarian cancer. In this study, we found that TG promoted the accumulation of ROS and MDA in A2780/DDP cells and downregulated the expression of key antioxidant molecules. In vivo, the survival rate of tumor-bearing nude mice was prolonged by TG without significant hepatotoxic reaction. The expression of key antioxidant molecules in tumor tissues was consistent with that in vitro. These findings revealed that TG disrupted homeostasis of redox reactions and induced ferroptosis in A2780/DDP cells, thereby enhancing cisplatin chemosensitivity of ovarian cancer. Overall, TG may be a novel potential therapeutic option for reversing resistance to cisplatin chemotherapy.

Oleic acid stimulates cell proliferation and BRD4–L-MYC-dependent glucose transporter transcription through PPARα activation in ovarian cancer cells

Fatty acids (FAs) play important roles in cell membrane structure maintenance, energy production via β-oxidation, and as extracellular signaling molecules. Prior studies have demonstrated that exposure of cancer cells to FAs affects cell survival, cell proliferation, and cell motility. Oleic acid (OA) has somewhat controversial effects in cancer cells, with both pro- and anti-cancer effects, depending on cell type. Our prior findings suggested that OA enhances cell survival in serum starved HNOA ovarian cancer cells by activating glycolysis, but not β-oxidation. Here, we pharmacologically examined the cellular mechanisms by which OA stimulates glycolysis in HNOA cells. OA induced cell cycle progression, leading to increase in cell number through peroxisome proliferator activated receptor (PPAR) α activation. OA-induced glycolysis was mediated by increased GLUT expression, and increases in GLUT expression were mediated by increased L-MYC expression. Furthermore, L-MYC expression was due to BRD4 activation. These findings suggested involvement of the BRD4-L-MYC-GLUT axis in OA-stimulated glycolysis. These results suggested that OA could activate PPARα to stimulate two pathways: glycolysis and cell cycle progression, and provided insight into the role of OA in ovarian cancer cell growth.

NDUFA8 is transcriptionally regulated by EP300/H3K27ac and promotes mitochondrial respiration to support proliferation and inhibit apoptosis in cervical cancer

Cervical cancer, a common malignancy in women, poses a significant health burden worldwide. In this study, we aimed to investigate the expression, function, and potential mechanisms of NADH: ubiquinone oxidoreductase subunit A8 (NDUFA8) in cervical cancer. The Gene Expression Profiling Interactive Analysis (GEPIA) database and immunohistochemical scoring were used to analyze NDUFA8 expression in cervical cancer tissues and normal tissues. Quantitative real-time PCR and Western blot analyses were performed to assess the expression level of NDUFA8 in cervical cancer cell lines. NDUFA8 knockdown or overexpression experiments were conducted to evaluate its impact on cell proliferation and apoptosis. The mitochondrial respiratory status was analyzed by measuring cellular oxygen consumption, adenosine triphosphate (ATP) levels, and the expression levels of Mitochondrial Complex I activity, and Mitochondrial Complex IV-associated proteins Cytochrome C Oxidase Subunit 5B (COX5B) and COX6C. NDUFA8 exhibited high expression levels in cervical cancer tissues, and these levels were correlated with reduced survival rates. A significant upregulation of NDUFA8 expression was observed in cervical cancer cell lines compared to normal cells. Silencing NDUFA8 hindered cell proliferation, promoted apoptosis, and concurrently suppressed cellular mitochondrial respiration, resulting in decreased levels of available ATP. Conversely, NDUFA8 overexpression induced the opposite effects. Herein, we also found that E1A Binding Protein P300 (EP300) overexpression facilitated Histone H3 Lysine 27 (H3K27) acetylation enrichment, enhancing the activity of the NDUFA8 promoter region. NDUFA8, which is highly expressed in cervical cancer, is regulated by transcriptional control via EP300/H3K27 acetylation. By promoting mitochondrial respiration, NDUFA8 contributes to cervical cancer cell proliferation and apoptosis. These findings provide novel insights into NDUFA8 as a therapeutic target in cervical cancer.

Sp1 promotes ovarian cancer cell migration through repressing miR-335 expression

Decreased miR-335 has been reported in a variety of cancers. We previously showed that miR-335 played an important role in ovarian cancer metastasis and prognosis. However, miR-335 is down-regulated in ovarian cancer by mechanisms that remain unclear. In silico analysis identified putative transcription factor specificity protein 1 (SP1) transcription factor binding sites in the miR-335 promoter. To investigate the relation between SP1 and miR-335, qRT-PCR was performed. Our results showed both Sp1 knockdown and mithramycin A increased miR-335 expression in ovarian cancer cell lines. Luciferase reporter assays indicated that Sp1 knockdown increased miR-335 transcriptional activity. ChIP experiments showed that Sp1 bound directly to miR-335 promoter. Moreover, transwell migration and wound-healing assays showed that Sp1 knockdown resulted in inhibited cell migration, which was in turn mitigated by miR-335 inhibitor. We propose that miR-335 was negatively regulated by SP1, which in turn contributes to miR-335 deregulation and tumor cells migration.

A novel FoxM1-PSMB4 axis contributes to proliferation and progression of cervical cancer

The abnormally high activity of the proteasome system is closely related to the occurrence and development of various tumors. PSMB4 is a non-catalytic subunit for the proteasome assembly. Although the reports from genetic screening have demonstrated it's a driver gene for cell growth in several types of solid tumor, its expression pattern and regulatory mechanisms in malignant diseases are still elusive. Here, we found that PSMB4 is overexpressed in cervical cancer tissues. And knockdown of PSMB4 significantly inhibited cervical cancer cell proliferation. The mechanistic study revealed that FoxM1, a master regulator of cell division, binds directly to the promoter region of PSMB4 and regulates the PSMB4 expression in the mRNA level. In addition, the data analysis from TCGA showed a positive correlation between FxoM1 and PSMB4 in cervical cancer. Furthermore, the loss of functional and rescue experiments confirmed that PSMB4 is required for FoxM1-driven cervical cancer cell proliferation. Collectively, our study explains the phenomenon of dysregulated expression of PSMB4 in cervical cancer tissues and verifies its driver effect on cancer cell proliferation. More importantly, it highlights a FoxM1-PSMB4 axis could be a potential target for the treatment of cervical cancer.

Therapeutic potential of targeting PCLAF in endometrial cancer: Insights from Wnt/β-catenin and P53 regulatory mechanisms

Endometrial cancer (EC), a widespread gynecological malignancy, has limited therapeutic options, particularly in patients with advanced, metastatic, or recurrent disease. PCLAF, a proliferation-related protein, is overexpressed in several tumors; however, its role and mechanism in EC remain largely unknown. Ten hub genes in EC were identified and predicted through bioinformatics analyses. The expression of PCLAF in EC was validated using molecular biology technology, while its function was investigated using in vitro proliferation, cell cycle, migration, and apoptosis assays. Mechanistically, the transcriptome and proteome sequencing revealed potential regulatory pathways for PCLAF in EC. Finally, experiments on animals were executed to test the Ishikawa cell growth in vivo. PCLAF exhibited high expression in both EC cells and tissues. Silencing PCLAF significantly impaired cell proliferation, migration and invasion, blocked G1 phase progression of the cell cycle and activated apoptosis. Sequencing results and western blot analysis confirmed that knockdown of EC cells inhibits the Wnt/β-catenin pathway and activates the p53 pathway. The in vivo results confirmed that PCLAF knockdown effectively inhibited EC cell growth. In conclusion, our findings suggest that silencing PCLAF hinders EC progression by suppressing the Wnt/β-catenin pathway and activating the p53 signaling pathway. This insight suggested that targeting PCLAF may offer a new therapeutic avenue for EC treatment.

Glucose deprivation induces cisplatin resistance through upregulation of SLC7A11 (xCT) expression in endometrial cancer cells

Cisplatin resistance poses a substantial barrier to the successful treatment of advanced endometrial cancer. Glucose deprivation in the tumor microenvironment, resulting from inadequate vascularization and rapid proliferation of cancer cells, may promote chemoresistance by modifying cellular metabolism and survival pathways. This study aimed to elucidate how glucose deprivation induces cisplatin resistance in endometrial cancer cells, focusing on the role of solute carrier family 7 member 11 (SLC7A11, xCT). The endometrial cancer cell lines HEC-1A and AN3CA were cultured under glucose-deprived and glucose-supplemented conditions. Cisplatin half-maximal inhibitory concentration (IC50) values, SLC7A11 expression, and reactive oxygen species (ROS) levels were assessed using cell proliferation assays, real-time PCR, Western blotting, and fluorescence assays. SLC7A11 was inhibited using small interfering RNA (siRNA) knockdown and the selective inhibitor HG106. Cisplatin-resistant cell lines were generated to evaluate the effect of SLC7A11 inhibition. Glucose deprivation significantly decreased cisplatin sensitivity and increased cisplatin IC50 values (P < 0.05). This reduction in sensitivity was accompanied by upregulation of SLC7A11 expression and decreased ROS levels (P < 0.05). Inhibition of SLC7A11, either by siRNA or HG106, increased cisplatin sensitivity and ROS production, even in cisplatin-resistant cells (P < 0.05). This effect was reversible with the antioxidant N-acetylcysteine. These findings demonstrate that glucose deprivation induces cisplatin resistance in endometrial cancer cells by upregulating SLC7A11, leading to reduced ROS levels and enhanced cell survival. Targeting SLC7A11 restores cisplatin sensitivity by elevating ROS production, even in cisplatin-resistant cells. The findings suggest that SLC7A11 is a promising therapeutic target for overcoming chemoresistance in endometrial cancer, potentially improving treatment outcomes and patient survival.

LINC00460 promotes angiogenesis by enhancing NF-κB-mediated VEGFA expression in cervical cancer cells

Angiogenesis is a characteristic of tumor development and is key for tumor growth and metastasis. LINC00460 is a long non-coding RNA that plays important yet complex roles in cancer development and progression. Here, we explored the functional mechanism of action of LINC00460 in cervical cancer (CC) angiogenesis for the first time. We found that conditioned medium (CM) from LINC00460-knockdown CC cells attenuated human umbilical vein endothelial cell (HUVEC) migration, invasion, and tube formation, whereas LINC00460 upregulation had the opposite effects. Mechanistically, LINC00460 stimulated VEGFA transcription. Suppressing VEGF-A reversed the effects of CM from LINC00460-overexpressing CC cells on HUVEC angiogenesis. Recombinant VEGFA eliminated the suppressive effects of CM from LINC00460-knockdown CC cells. Furthermore, LINC00460 enhanced VEGFA expression and promoted angiogenesis by activating the NF-κB pathway. Our data illustrate that LINC00460 can promote angiogenesis by activating the NF-κB-VEGFA axis, suggesting that the axis is a promising target for blocking tumor angiogenesis.

Network pharmacology and metabolomics elucidate the underlying effects and mechanisms of maackiain against endometrial cancer

Endometrial carcinoma (EC), a prevalent gynecological cancer, is characterized by rising incidence and mortality rates, highlighting the need for novel treatments to improve patient outcomes. Maackiain (MA) is a natural compound isolated from common herbal medicines, that has been reported to have anti-cancer effects. However, the underlying roles and mechanisms concerning EC remain unclear. This study focused on deeply exploring the potential roles and mechanisms of MA against EC by network pharmacology, experimentally validated, metabolomics, and molecular docking. A total of 86 potential targets of MA against EC were identified by network pharmacology. In vitro experiments further confirmed network pharmacology' predictions. In addition to suppressing EC cell proliferation, MA also paused the cell cycle at the G2/M phase in a dose-dependent manner. This effect is accompanied by increased p21 and phospho-p53 expression, as well as reduced expression of CDK1 and CCNB1. Furthermore, cell metabolomics analysis revealed that 285 metabolites were changed after MA administration, which majorly affects glycerophospholipid metabolism, nucleotide metabolism, choline metabolism in cancer, and purine metabolism. Combination network pharmacology, metabolomics, and molecular docking, PLA2G10, PDE4D, and PDE5A were found to be potential targets for therapeutic intervention. These findings underlined that MA has anti-EC potential by modulating multiple targets including PLA2G10, PDE4D, and PDE5A, inhibiting EC cell proliferation, inducing G2/M phase arrest, and causing metabolic shifts. This study provides theoretical support for advanced experimental research on its clinical applications.

Extracellular biophysical environment: Guilty of being a modulator of drug sensitivity in ovarian cancer cells

The roles of the extracellular biophysical environment in cancer are barely studied. This study considers the possibility that cell-like topography of a cancer cell environment may influence chemo-responses. Here, a novel bioimprinting technique was employed to produce cell-like topography on the polystyrene substrates used for cell culture. In this work, we have shown that extracellular biophysical cues generated from the topography alter the chemosensitivity of ovarian cancer cells. The three-dimensionality of the bioimprinted surface altered the cell-surface interaction, which consequently modulated intracellular signalling and chemoresponses. Sensitivity to platinum was altered more than that to paclitaxel. The effect was largely mediated through the integrin/focal adhesion system and the Rho/ROCK pathway. Moreover, the results provided evidence that biophysical cues also modulate MAPK signalling associated with chemo-resistance in ovarian cancer. Therefore, the novel findings from of this study revealed for the first time that the effects of the biophysical environment, such as substrate topography, influences ovarian cancer cell responses to clinical drugs. These observations suggest that a full clinical understanding of ovarian cancer will include biophysical aspects of tumour microenvironment.

Poziotinib suppresses ovarian cancer stem cell growth via inhibition of HER4-mediated STAT5 pathway

Epithelial ovarian cancer (EOC) is the most lethal gynecological malignancy, with an overall 5-year survival rate of only 30%. EOC is associated with drug resistance, frequent recurrence, and poor prognosis. A major contributor toward drug resistance might be cancer stem cells (CSCs), which may remain after chemotherapy. Here, we aimed to find therapeutic agents that target ovarian CSCs. We performed a high-throughput screening using the Clinical Compound Library with a sphere culture of A2780 EOCs. Poziotinib, a pan-human epidermal growth factor receptor (HER) inhibitor, decreased sphere formation, viability, and proliferation, and induced G1 cell cycle arrest and apoptosis in ovarian CSCs. In addition, poziotinib suppressed stemness and disrupted downstream signaling of Wnt/β-catenin, Notch, and Hedgehog pathways, which contribute to many characteristics of CSCs. Interestingly, HER4 was overexpressed in ovarian CSCs and Poziotinib reduced the phosphorylation of STAT5, AKT, and ERK, which are regulated by HER4. Our results suggest that HER4 may be a promising therapeutic target for ovarian CSCs, and that poziotinib may be an effective therapeutic option for the prevention of ovarian cancer recurrence.

TGF-β1 fucosylation enhances the autophagy and mitophagy via PI3K/Akt and Ras-Raf-MEK-ERK in ovarian carcinoma

Transforming growth factor-β, a cell secretion factor of the TGF-β superfamily, is involved in the regulation of cell proliferation, differentiation, cytoskeleton formation, migration, invasion and other biological behaviors. Autophagy and mitophagy play an important role in tumor progression by regulating self-digestion, and degradation and reuse of cells and mitochondria. In this study, changes in autophagy and mitophagy processes in ovarian cancer cells under TGF-β1 treatment were detected via Western blot and immunofluorescence, as well as the role of fucosylation modification. Changes in mitochondrial membrane potential in response to TGF-β1 and fucosylation were detected via immunofluorescence. The effects of TGF-β1 and its fucosylation on autophagic flux were further determined by transient transfection of cells with Ad-mRFP-GFP-LC3 adenovirus. TGF-β1 clearly promoted autophagy and mitophagy in ovarian cancer cells. TGF-β1 fucosylation stimulated these regulatory effects on ovarian cancer cells via modulation of PI3K/Akt and Ras-Raf-MEK-ERK pathways through TAK1. Our collective data support the physiological significance of TGF-β1 and provide a novel direction for targeted therapy for ovarian cancer.

Ubiquitin-specific protease 14 regulates ovarian cancer cisplatin-resistance by stabilizing BCL6 oncoprotein

Ubiquitin-specific protease 14 (USP14) is one of the three proteasome-associated deubiquitinating enzymes and implicated in the progression of various cancers. However, the role of USP14 in ovarian cancer remains unknown. By using an unbiased qRT-PCR screen, here we show that USP14 is considerably increased in cisplatin-resistant ovarian cancer cells. Overexpression of USP14 confers resistance to cisplatin-sensitive ovarian cancer cells. Genetic or pharmacological inhibition of USP14 is able to reverse cisplatin-resistance of ovarian cancer cells, which was accompanied by decreased protein expression of BCL6. Besides, BCL6 protein level was also increased in cisplatin-resistant ovarian cancer cells and silencing of BCL6 in these cells restored their sensitivity to cisplatin. At the molecular lever, we found that USP14 interacted with BCL6 and prevented it from proteasomal-dependent degradation. Thus, our results provide a rationale to target USP14-BCL6 axis in ovarian cancer that may be therapeutically beneficial.

Use of chimeric antigen receptor NK-92 cells to target mesothelin in ovarian cancer

Mesothelin (MSLN) has been reported to be overexpressed in ovarian cancer and may be an ideal target for immunotherapy. Recent studies have suggested that natural killer (NK) cells may be better chimeric antigen receptor (CAR) drivers because of their favorable innate characteristics, such as directly recognizing and killing tumor cells, resulting in a graft-versus-tumor effect but irresponsible for graft-versus-host disease (GVHD). The therapeutic effects of CAR-engineered NK cells targeting MSLN in ovarian cancer have not been evaluated. In this study, MSLN- and CD19-targeted CAR NK-92 (MSLN- and CD19-CAR NK) cells were constructed. Both MSLN- and CD19-CAR molecules were highly expressed on the surface of NK-92 cells following lentiviral gene transduction. MSLN-CAR NK cells specifically killed MSLN-positive ovarian cancer cells (OVCAR-3 and SK-OV-3), rather than MSLN-negative cells (SK-HEP-1), in vitro. Moreover, compared with parental NK-92 cells and CD19-CAR NK cells, stronger cytokine secretion was detected in MSLN-CAR NK cells cocultured with OVCAR-3 and SK-OV-3. Furthermore, MSLN-CAR NK cells effectively eliminated ovarian cancer cells in both subcutaneous and intraperitoneal tumor models; these cells also significantly prolonged the survival of intraperitoneally tumor-bearing mice. These results demonstrate that MSLN-CAR NK cells have robust specific antitumor activity, both in vitro and in vivo, suggesting that mesothelin could be a potential target for CAR NK cells and could be applied in the treatment of ovarian cancer.

NCK1-AS1 promotes NCK1 expression to facilitate tumorigenesis and chemo-resistance in ovarian cancer

Long non-coding RNAs (lncRNAs) have been unveiled to play crucial parts in tumorigenesis and chemo-resistance of multiple cancers. Herein, we explored the role of NCK1-AS1 in ovarian cancer (OC). As indicated by TCGA, NCK1-AS1 was markedly upregulated in OC tissues. Besides, we found a dramatic upregulation of NCK1-AS1 in OC cell lines relative to the normal IOSE cells. Interestingly, silencing NCK1-AS1 confined cell proliferation, induced apoptosis and suppressed migration and invasion as well as enhanced DDP sensitivity in OC cells. As for mechanistic investigation, starBase (http://starbase.sysu.edu.cn/) suggested that NCK1-AS1 expression in OC tissues was significantly positively correlated with its adjacent gene, NCK adaptor protein 1 (NCK1). Furtherly, we demonstrated that the cytoplasmic NCK1-AS1 competed with NCK1 mRNA for miR-137 binding to boost NCK1 mRNA expression. Importantly, miR-137 inhibition could only offset the suppression of NCK1-AS1 depletion on NCK1 mRNA level but not the protein level. Moreover, NCK1-AS1 stabilized NCK1 protein by hindering c-Cbl-induced degradation via directly interacting with c-Cbl. Furthermore, NCK1 upregulation reversed the influences of NCK1-AS1 inhibition on the biological behaviors and DDP resistance of OC cells. This study disclosed a NCK1-AS1/NCK1 axis in regulating OC progression and chemo-resistance, opening a new path for treatment and chemo-resistance overcoming in OC.

CNR1 may reverse progesterone-resistance of endometrial cancer through the ERK pathway

Endocrine therapy is a promising treatment for endometrial cancer (EC) that preserves fertility, however, progesterone-resistance is currently the major challenges. The Cancer Genome Atlas (TCGA) database analysis showed that CNR1 was closely have a negative correlation with overall survival (OS) and relapse-free survival (RFS) in endometrial cancer. To explore the role of CNR1 in progesterone resistance and possible molecular regulation mechanism, we established stable progesterone-resistant cell lines (IshikawaPR) via progesterone tolerance of ordinary cancer cells (Ishikawa). The difference of CNR1 level in two cell lines was assessed by MTT, RT-PCR, Western blot, immunofluorescence. Then, lentiviruses constructed CNR1-knockdown with GV248 as the tool vector were used to transfect IshikwaPR cells, and the changes of biological behavior and progesterone sensitivity was verified respectively through plate cloning experiment, EdU assay, flow cytometry cycle analysis, transwell, Scratch test, etc. We founded after CNR1 was knocked down, the proliferative activity and ability to migrate of IshikawaPR cells decreased, progesterone-response sensitivity could be improved. Moreover, knockdown of CNR1 can also down-regulate ERK and NFκ B expression and activation. Furthermore, subcutaneous xenograft in nude mice was tested similarly in vivo. The above datas suggest that targeting CNR1 may reverse the progesterone resistance in endometrial cancer and may coordinate the role of ERK pathway activation.

Combination of metformin and RG7388 enhances inhibition of growth and induction of apoptosis of ovarian cancer cells through the PI3K/AKT/mTOR pathway

Ovarian cancer is a gynecological cancer that has the highest mortality rate and is often resistant to conventional treatments. Therefore, development of new therapies is essential. Metformin (MET), which is the priority drug for treatment of type 2 diabetes, has received increasing attention because of its anti-tumor effects. Here, we examined combined anti-tumor effects of MET and RG7388, the only MDM2 (mouse double minute 2 homolog) antagonist that has entered phase III clinical trials, on ovarian cancer cell lines. We examined effects on proliferation by Cell Counting Kit-8 (CCK-8) and colony formation assays, and effects on apoptosis by flow cytometric analysis and Hoechst staining. Western blotting was used to measure protein expression in cells and tissues treated with MET and/or RG7388. Flow cytometry was used to measure reactive oxygen species (ROS). We also examined the effects of MET and/or RG7388 on inhibition of A2780 cell growth in vivo. The combination of MET and RG7388 significantly increased growth inhibition, apoptosis, and ROS of A2780 and SKOV3 cells compared with either agent alone. Additionally, in vitro and in vivo results showed that MET and/or RG7388 inhibited the phosphoinositide 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) pathway and their combination had a stronger effect. Our findings suggest that the combination of MET and RG7388 enhances growth inhibition and apoptosis induction of ovarian cancer cells through the PI3K/AKT/mTOR pathway and accumulation of intracellular ROS.

MKNK2 enhances chemoresistance of ovarian cancer by suppressing autophagy via miR-125b

Chemoresistance is a major cause for high mortality and poor survival in patients with ovarian cancer. Changes of cellular autophagy is associated with tumor cell chemoresistance. MAP kinase interacting serine/threonine kinase 2 (MKNK2) belongs to the protein kinase superfamily mediating cell cycle, apoptosis and angiogenesis. However, its effects on chemoresistance during ovarian cancer development remain unclear. In this study, we found that MKNK2 expression levels were markedly up-regulated in chemoresistant ovarian cancer cells compared with the sensitive cells. In addition, significantly increased expression of MKNK2 was detected in clinical ovarian cancer tissues, particularly in tumor samples from patients with drug resistance, and high MKNK2 expression is closely associated with poor prognosis. Our in vitro experiments subsequently showed that MKNK2 knockdown markedly reduced the proliferation of chemoresistant ovarian cancer cells, which was confirmed in SKOV3/DDP xenograft mouse models. Importantly, MKNK2 knockdown considerably induced autophagy in ovarian cancer cells with drug resistance, which was involved in the suppression of cell proliferation. Of note, we showed that miR-125b directly targeted MKNK2, and a negative correlation was observed between the expression of them in clinical tumor tissues. MKNK2 silence also increased miR-125b expression levels in drug-resistant ovarian cancer cells. Intriguingly, MKNK2 knockdown-suppressed cell proliferation and -induced autophagy were almost abrogated by miR-125b inhibition in chemoresistant ovarian cancer cells. Together, these findings demonstrated that MNKN2 is responsible for chemoresistance in ovarian cancer through modulating autophagy by targeting miR-125b, which may be a promising therapeutic target to develop strategies against ovarian cancer with drug resistance.

Identification of the deubiquitinase USP28 as a novel molecular therapeutic target of ovarian cancer

Ubiquitin specific proteinase 28 (USP28) is a member of the deubiquitylating enzymes, which are mainly involved in cell cycle, apoptosis and DNA damage repair. Although USP28 has been found to be upregulated in some tumors, its role in ovarian cancer (OV) remains unclear. Here we show that USP28 was highly expressed in OV samples compared with normal ovarian tissue, and OV patients with higher USP28 levels had a worse prognosis. We found that the abnormal expression of USP28 mRNA in OV was related to the activation of β-catenin signaling pathway, and USP28 was a transcriptional target gene of the β-catenin/YAP1/TBX5 complex. In addition, genetic ablation or pharmacological inhibition of USP28 impaired the proliferation ability of OV cells in vitro and in vivo. In conclusion, our findings show that β-catenin/YAP1/TBX5-mediated aberrant expression of USP28 promotes the malignant phenotype of OV, suggesting that USP28 may be a therapeutic target for OV.

LncRNA AL592284.1 facilitates proliferation and metastasis of cervical cancer cells via miR-30a-5p/Vimentin/EMT axis

Long non-coding RNAs (lncRNAs) are implicated in cancer-related cellular behaviors. Our research aimed to explore the biological functions of lncRNA AL592284.1 (AL592284.1) in cervical cancer (CC). qRT-PCR was performed to examine AL592284.1 expressions in cell lines and tumor specimens. To study the roles of AL592284.1 on malignant behaviors in both in vitro and in vivo, Loss-of-function assays were carried out. Besides, bioinformatics prediction and dual-luciferase reporter assays were performed to reveal the interaction among AL592284.1 and its target genes. The functions of the AL592284.1/miR-30a-5p/Vimentin axis in CC cells was clarified by rescue assays. We observed that the levels of AL592284.1 in CC were distinctly increased. Functional assays revealed that knockdown of AL592284.1 suppressed the proliferation, migration, invasion and EMT progress of CC cells. Luciferase reporter assay confirmed that miR-30a-5p/Vimentin regulatory axis is the direct downstream of AL592284.1. Rescue experiments indicated that AL592284.1 induced overexpression of Vimentin via sponging miR-30a-5p, resulting in the promotion of CC progression. The present study proves that AL592284.1 plays an tumor-promotive role in CC via regulating the miR-30a-5p/Vimentin axis, and inhibition of AL592284.1 may pave the way for CC treatment.

Hypoxia-induced CNPY2 upregulation promotes glycolysis in cervical cancer through activation of AKT pathway

This study aimed to investigate the function and mechanism of the protein-coding gene CNPY2 in the glycolysis of cervical cancer cells. Cells were exposed to normoxia and hypoxia conditions. Knockdown and ectopic overexpression of CNPY2 were achieved by transfection of small interfering RNA (siRNA) specific to CNPY2 or CNPY2 overexpression vectors, respectively. Quantitative real-time PCR and Western blot were used to evaluate CNPY2 expression in patient specimens and different cervical cancer cell lines under normoxia or hypoxia conditions. Cell viability was assessed by MTT and colony formation assays. Glucose consumption, lactate production, oxygen consumption and ATP production were analyzed by enzyme-linked immunosorbent assays. Dual-luciferase reporter assay and chromatin immunoprecipitation assay were performed to detect interaction between hypoxia-induced factor 1α (HIF-1α) on CNPY2 promoter. CNPY2 upregulation was a characteristic of cervical cancer and correlated with poor prognosis. Knockdown and overexpression of CNPY2 inhibited and promoted proliferation glucose consumption, lactate production, oxygen consumption and ATP production in cervical cancer cells, respectively. CNPY2 was transcriptionally regulated by HIF-1α. The hypoxia-induced "Warburg effect" in cervical cancer cells was at least partially dependent on the CNPY2/AKT signaling pathway. Hypoxia-induced CNPY2 promoted glycolysis in cervical cancer cells by activating the AKT pathway. CNPY2 may serve as a potential diagnostic marker and therapeutic target for cervical cancer patients.

Oleanolic acid inhibits cervical cancer Hela cell proliferation through modulation of the ACSL4 ferroptosis signaling pathway

Cervical cancer remains the leading cause of cancerous death among women worldwide. Oleanolic acid (OA) is a substance that occurs naturally in the leaves, fruits, and rhizomes of plants and has anti-cancer activity. In this study, tumor-bearing mice were used as the animal model and Hela cells were used as cellular model. In vivo experiments have showed that OA significantly reduced the size and mass of cervical cancer tumors in mice. In vitro experiments have showed that OA significantly reduced the viability and proliferative capacity of Hela cells. In both in vivo and in vitro assays, OA increased the oxidative stress levels and Fe

Immune escape between endoplasmic reticulum stress-related cancer cells and exhausted CD8+T cells leads to neoadjuvant chemotherapy resistance in ovarian cancer

Our study aims to explore the effects of neoadjuvant chemotherapy (NACT) on tumour cells and immune cells in the immune microenvironment of patients with high-grade serous ovarian cancer (HGSOC). Single-cell RNA sequencing data of paired ovarian cancer tissues were analysed before and after NACT in 11 patients with HGSOC. The effect of NACT on two major cell components of the tumour microenvironment, epithelial cells and CD8+T cells, was investigated. The mechanisms of epithelial cell evasion by NACT and immune killing were explored from the perspectives of gene expression, functional characteristics, transcriptional regulation, and cell communication. Key targets for reversing NACT resistance were identified and possible therapeutic strategies proposed. While NACT improved the de novo differentiation of anti-tumour CD8+T cells, enhancing their anti-tumour function, it increased the proportion of cancer cells with high HSP90B1 expression. Thus, the potential reasons for NACT resistance were identified as: 1) high levels of endoplasmic reticulum stress (ERS) characteristics, 2) high expression of the MDK-NCL ligand-receptor pair between them and exhausted CD8+T cells before NACT, and 3) high expression of the NECTIN2-TIGIT immune ligand-receptor pair between them and exhausted CD8+T cells after NACT. Thus, our study reveals the mechanisms underlying NACT resistance in patients with HGSOC from the perspective of the independent and interactive roles of cancer cells and CD8+T cells. We propose therapeutic strategies targeting the ERS marker HSP90B1 and the immune escape marker MDK before or during NACT, while targeting NECTIN2 blockade after NACT. This approach may offer new insights into combination treatments for patients with HGSOC displaying NACT resistance.

Aberrant upregulation of CDK1 contributes to medroxyprogesterone acetate (MPA) resistance in cancer-associated fibroblasts of the endometrium

The response to medroxyprogesterone acetate (MPA) decreases as endometrial disease progresses from the benign to malignancy. In a mouse model, progesterone receptor (PR) expression in normal fibroblasts is accountable for the MPA's inhibitory effects in cancer cells. However, it is still unclear, if and how, fibroblasts from human tumors respond to MPA. In this study, three benign-associated fibroblasts (BAFs) and four cancer-associated fibroblasts (CAFs) were isolated from human benign and cancerous endometrial tissues, respectively, to examine MPA activation on PR signaling. PR-B protein expression were heterogeneously expressed in both CAFs and BAFs, despite a lower mRNA expression in the former. In a luciferase reporter assay, MPA treatment stimulated some PR DNA-binding activity in BAFs but not in CAFs. Yet, activation of PR target gene was generally more pronounced in MPA-treated CAFs compared to BAFs. Cyclin-dependent kinase 1 (CDK1) was exclusively upregulated by 10 nM MPA in CAFs (5.1-fold vs. 1.1-fold in BAFs, P < 0.05), leading to a higher CDK1 protein expression. Subsequently in a dose-response study, CAFs showed an average of ∼20% higher cell viability when compared to BAFs, indicative of drug resistance to MPA. MPA resistance was also observed in EC-CAFs co-culture, when MPA-treated cells showed greater tumor spheroid formation than in EC-BAFs co-culture (2-fold, P < 0.01). The increased cell viability observed in CAFs was reversed with mifepristone (RU486), a PR antagonist which suppressed MPA-induced CDK1 expression. This indicates that MPA-induced abnormal upregulation of CDK1 may contribute to the enhanced CAFs cell proliferation, suggesting a new mechanism of MPA resistance within endometrial cancer microenvironment.

PTPN2 acts as a tumor suppressor and therapeutic target in ovarian cancer

Ovarian cancer (OC) remains the most lethal gynecological malignancy, with metastasis and chemoresistance driving poor outcomes. Non-receptor protein tyrosine phosphatase 2 (PTPN2) is a critical regulator of oncogenic signaling pathways, but its role in OC progression remains poorly understood. Here, we identify PTPN2 as a critical tumor suppressor in OC through integrated bioinformatics and functional studies. Bioinformatics analysis revealed significant PTPN2 downregulation in OC tissues, correlating with advanced tumor stage and poor patient survival. Experimental validation confirmed reduced PTPN2 expression at both mRNA and protein levels in clinical specimens. Functional studies demonstrated that PTPN2 overexpression inhibits OC cell proliferation, migration, and motility. Mechanistically, PTPN2 maintains epithelial cell characteristics by upregulating E-cadherin while suppressing mesenchymal markers Snail and Twist through negative regulation of ERK1/2 phosphorylation. Our findings not only expand the current understanding of PTPN2's role in cancer biology but also suggest its dual potential as both a prognostic biomarker and a promising therapeutic target for OC treatment.

The effect and mechanism of areca nut in ovarian cancer were investigated based on network pharmacology, molecular docking, and in vitro experiments

Ovarian cancer ranks as the leading cause of death among gynecological malignancies[1, 2]. Areca nut has demonstrated notable antitumor activity, yet its underlying mechanism remains incompletely understood. To explore the potential of areca nut - derived active ingredients in regulating ovarian cancer progression via the PTEN/AKT1 signaling axis. Targets related to areca nut were screened from the TCMSP database, while ovarian - cancer - associated targets were retrieved from GeneCards and DisGeNET databases. Intersection targets were identified using Venn analysis. Core pathways were annotated through enrichment analysis with Metascape and DAVID databases. Molecular docking was performed to validate the binding energy intensity between areca nut active ingredients and their corresponding receptors. In addition, the effect of arecoline on ovarian cancer cells was investigated in vitro. A total of 50 common targets were identified from 139 areca nut - related targets and 1914 ovarian cancer - associated targets. Pathway enrichment analysis revealed significant enrichment of the PI3K/AKT pathway. The core targets, PTEN (-5.3 kJ/mol) and AKT1 (-5.4 kJ/mol), exhibited strong binding to the active components of areca nut. Moreover, arecoline inhibited the proliferation and induced apoptosis in ovarian cancer cells. In conclusion, this study provides a solid scientific basis for exploring the action mechanism of areca nut.

Keratinocyte-derived extracellular vesicles induce macrophage polarization toward an M1-like phenotype

Multiple reports have shown an effect of keratinocyte-derived extracellular vesicles (EVs) on keratinocytes and other cell types. However, the contribution of keratinocyte-derived EVs under physiological and pathological conditions is not fully elucidated. Therefore, whether there is an effect of EVs on macrophages in cervical cancer (CC) is also unknown. Here, we evaluated the effect of tumor and non-tumor keratinocyte-derived EVs on the polarization of peripheral blood mononuclear cells (PBMCs)-derived macrophages and THP-1 cell line. Flow cytometric evaluation of macrophages cultured in the presence of keratinocyte-derived EVs mainly indicated an increase in classical activation markers CD80 and CD86 (M1 phenotype) and little or no modification of alternative activation markers (M2 phenotype). ELISA evaluation of macrophage supernatants revealed an increase in the secretion of proinflammatory cytokines such as IL-1β and IL-6. On the other hand, TGF-β was not significantly modified and only EVs derived from non-cancerous keratinocytes induced a significant increase in IL-10. The expression levels of transcripts associated with the M1 phenotype were also evaluated by qRT-PCR with similar results to ELISA for TGF-β and IL-10; but also an increase in the expression of HLA-DRα and TNF-α was observed, and no statistically significant changes in ARG1. The ROS production was also evaluated and this increase mainly in macrophages treated with CC keratinocytes-derived EVs. So, our results suggest that the uptake of EVs derived from released by non-tumor and cervical cancer keratinocytes promotes in macrophages their polarization to an M1-like phenotype.

Poly(ADP-ribose) polymerase1 (PARP1) and PARP inhibitors: New frontiers in cervical cancer

Cervical cancer affects more than half a million women and treatment options for advanced disease and recurrence is limited. Poly (ADP-ribose) polymerase1 (PARP1) is a critical nuclear protein regulating several components and functions of cellular machinery, including cancer. PARP1 expression and activity plays a crucial dynamics in the tumor microenvironment. PARP inhibitors are being considered as a viable option for treating BRCA deficient ovarian and breast cancer patients. However, the role of PARP1 in cervical cancer tumorigenesis is less known. The aim of the present review is to provide a comprehensive insight about the role of PARP1 in cervical cancer pathogenesis in context to PARP1 expression as a molecular marker for identifying cancer and in predicting treatment response and prognosis. PARP1 expression is found to be elevated in cervical cancer tissues in comparison to that in the normal surrounding tissues. The cellular proteins linked with PARP1 have been described along with the association of SNPs in PARP1 gene with cervical cancer. Promising results of PARP inhibitors with immunotherapy and clinical trials with cisplatin have also been discussed. This review provides an up-to-date description of PARP1 expression, its role in cervical cancer pathogenesis and reported clinical trials of PARP inhibitors in adjuvant therapy.

Tissue factor pathway inhibitor-2 inhibits integrin β1 activation and focal adhesion formation and suppresses peritoneal ovarian cancer dissemination in mice

Tissue factor pathway inhibitor-2 (TFPI2) is a Kunitz-type serine protease inhibitor and an ovarian clear cell carcinoma (CCC) biomarker. TFPI2 is expressed in several cancers and exerts tumor-suppressive effects; however, the role of TFPI2 in the CCC cell phenotype remains unclear. Therefore, in this study, we investigated the function of TFPI2 by establishing a gene knockout (KO) in ES-2 CCC cells and observed the change in phenotypes in vitro and in vivo. TFPI2 KO inhibited ES-2 cell proliferation, increased extracellular matrix protein adhesion, enhanced focal adhesion formation and activated integrin β1 cell surface clustering in vitro, and markedly increased ES-2 tumor growth and dissemination in the peritoneal cavity of a mouse xenograft model. These findings suggest a novel function of TFPI2 expression in suppressing the formation of focal adhesions in CCC cells, potentially by activating integrin β1. This function plays a role in the peritoneal growth characteristics of CCC cells.

Overcoming cisplatin resistance in ovarian cancer: A novel approach via mitochondrial targeting peptide Pal-pHK-pKV

Cisplatin (DDP) resistance in advanced stages of ovarian cancer significantly reduces survival rates. Mitochondria may serve as a potential therapeutic target for ovarian cancer. Pal-pHK-pKV is a mitochondrial targeting peptide synthesized by supramolecular assembly. Our study aims to investigate whether Pal-pHK-pKV serves as a useful strategy to reverse DDP resistance in ovarian cancer. Subcutaneous tumor implantation of the DDP-resistant ovarian cancer cell line A2780CP was conducted in nude mice, and drugs were administered intraperitoneally to compare the inhibitory effects of Pal-pHK-pKV and DDP on A2780CP cells in vivo. Combination index values were calculated for various concentrations of DDP and Pal-pHK-pKV to determine the optimal combination concentration. Mitochondrial membrane potential, cytochrome C distribution and immunofluorescence were also measured. Our studies demonstrated that Pal-pHK-pKV treatment reduced the proliferation, invasion and metastasis of ovarian cancer cells and impaired mitochondrial function. Furthermore, the combination of Pal-pHK-pKV and DDP exhibited a synergistic effect. Mechanistically, Pal-pHK-pKV can impair mitochondrial function, reduce mitochondrial membrane potential and release ROS. On the other hand, Pal-pHK-pKV can affect ERK pathway activation and inhibit tumor development. In conclusion, the mitochondria-specific amphiphilic peptide Pal-pHK-pKV provides a novel approach for treating ovarian cancer and may potentially overcome DDP drug resistance.

Small Extracellular Vesicles from adipose-derived stem cells suppress cell proliferation by delivering the let-7 family of microRNAs in ovarian cancer

Ovarian cancer is the leading cause of death among women with gynecological cancer, and novel treatment options are urgently needed. Extracellular vesicles (EVs), including exosomes, may be one of the most promising therapeutic tools for various diseases. In this study, we aimed to investigate the therapeutic effects of adipose-derived stem cell-derived EVs (ADSC-EVs) on ovarian cancer cell lines. ADSCs and the ovarian cancer cell lines SKOV3 and OV90 were used for analysis. ADSC-EVs were isolated through ultracentrifugation and validated using a cryotransmission electron microscope, nanoparticle tracking analysis, and western blotting. Then, the effect of ADSC-EVs on ovarian cancer cells was investigated using IncuCyte and microRNA sequencing. Moreover, the potential functions of miRNAs were evaluated by gain-of function analysis and in silico analysis. ADSC-EVs suppressed SKOV3 and OV90 cell proliferation. In particular, small EVs (sEVs) from ADSCs exhibited a stronger antitumor effect than ADSC-medium/large EVs (m/lEVs). Comparison of the miRNA profiles between ADSC-sEVs and ADSC-m/lEVs, along with downstream pathway analysis, suggested the involvement of the let-7 family. Overexpression of hsa-let-7b-5p and hsa-let-7e-5p significantly suppressed the proliferation of SKOV3 cells. In silico analysis revealed that four potential target genes of hsa-let-7b-5p and hsa-let-7e-5p were significantly associated with the prognoses of the patients. ADSC-sEVs had a stronger antitumor effect than ADSC-m/lEVs. Hsa-let-7b-5p and hsa-let-7e-5p, which are highly abundant in ADSC-sEVs, suppressed cell proliferation. These findings may open up new possibilities for therapeutic approaches using ADSC-sEVs.

Involvement of ATMIN-DYNLL1-MRN axis in the progression and aggressiveness of serous ovarian cancer

The loss of DYNLL1 contributes to chemoresistance in ovarian cancer. DYNLL1 binds to MRE11, a component of MRN complex (MRE11-RAD50-NBS1), and limits its function in homologous recombination (HR) repair in BRCA1-mutant cells. Decreased activity of MRE11 results in less HR-repair events and thus leads to higher sensitivity against DNA-damaging agents such as cisplatin. Therefore, a better understanding of the cellular changes in DYNLL1-MRN axis in ovarian cancer is needed. Here, we showed that DYNLL1 overexpression leads to decreased chemoresistance even in BRCA-proficient ovarian cancer cells. ATMIN, a transcriptional activator of DYNLL1, showed decreased expression; however, two components of MRN complex, MRE11 and NBS1 (NBN), showed increased expression in high grade compared to low grade serous ovarian cancer. We found that the components of MRN complex (MRE11-RAD50-NBS1) have higher protein levels in sites of omental metastasis and serous tubal intraepithelial carcinoma (STIC) compared to surrounding non-malignant stromal cells in patients with high grade serous ovarian cancer. We showed that the percentage of copy number variation (CNV) events in genes encoding ATMIN, DYNLL1, MRE11 and NBN are the highest in ovarian cancer among other cancer types. ATMIN and DYNLL1 genes are mostly characterized by copy number losses; however, CNV events in MRN complex components are mostly copy number gains. This study highlights the importance of ATMIN-DYNLL1-MRN axis in the development, progression and therapy response of ovarian cancer. MRN levels in ovarian cancer that differ from adjacent, non-malignant tissues may represent actionable therapeutic vulnerabilities.

Combined use of cisplatin plus natural killer cells overcomes immunoresistance of cisplatin resistant ovarian cancer

Standard chemotherapy for ovarian cancers is often abrogated by drug resistance. Specifically, resistance to cisplatin is a major clinical obstacle to successful treatment of ovarian cancers. The aim of this study was to develop a therapeutic strategy using natural killer (NK) cells to treat cisplatin-resistant ovarian cancers. First, we compared the responses of ovarian cancer cell line A2780 and its cisplatin-resistant counterpart, A2780cis, to treatment with cisplatin plus NK92MI cells. Although combined treatment induces apoptosis of ovarian cancer cells via ROS-dependent and -independent mechanisms, A2780cis were resistant to NK92MI cell-mediated cytotoxicity. We found that A2780cis cells showed markedly higher expression of immune checkpoint protein, PD-L1, than the parental cells. Although pretreatment of A2780cis cells with cisplatin stimulated further expression of PD-L1, it also increased expression of ULBP ligands, which are activating receptors on NK92MI cells, both in vitro and in vivo. These findings suggest that combined use of cisplatin plus NK cell-mediated immunotherapy could overcome immunoresistance of chemoresistant ovarian cancers.

NOL4L, a novel nuclear protein, promotes cell proliferation and metastasis by enhancing the PI3K/AKT pathway in ovarian cancer

Nucleolar protein 4-like (NOL4L) was first identified in acute myeloid leukaemia. Then, it was verified to be involved in cell progression in neuroblastoma. However, the functional role of NOL4L in tumor proliferation and metastasis and the underlying molecular mechanism(s) are not fully understood. Immunohistochemistry (IHC) assays were performed in patient tissues to reveal NOL4L expression profiles. Then, we knocked down NOL4L in two ovarian cancer cell lines (Skov3-ip1 and Hey), and cell-based in-vitro and in-vivo assays were subsequently conducted to gain insight into the underlying mechanism of NOL4L in ovarian cancer. We confirmed that the expression of NOL4L was higher in tumor tissues, especially in peritoneal metastatic tissues. Furthermore, we observed that NOL4L was related to prognosis in ovarian cancer patients. Next, we conducted CCK-8 assays, colony formation assays, migration and invasion experiments and wound healing assays and verified that NOL4L could promote proliferation and metastasis in ovarian cancer cells. In addition, NOL4L promoted tumor progression and metastasis in a nude mouse model. Mechanistically, we demonstrated that NOL4L influenced gene expression in the PI3K/AKT pathway. Overall, our study provides genetic and biochemical evidence that NOL4L is critical for tumor progression and metastasis in ovarian cancer cells. Thus, it could serve as a target for antimetastatic therapy in ovarian cancer.

Bractoppin, a BRCA1 carboxy-terminal domain (BRCT) inhibitor, suppresses tumor progression in ovarian borderline tumor organoids

Borderline ovarian tumors are a special class of ovarian tumors between benign and malignant, which are not sensitive to traditional chemotherapy regimens, and the development of target drugs is limited due to the lack of cell lines. Tumor organoids can well preserve the genetic characteristics of the primary tumor, but there are only a few reports of application in borderline tumors. In this study, we successfully generated 13 ovarian borderline tumor organoids and tested the antitumor activity of Bractoppin, a BRCA1 carboxy-terminal domain (BRCT) inhibitor. Bractoppin promotes organoid apoptosis. Mechanistically, Bractoppin can inhibit organoid cell cycle progression, inhibit the repair of DSB damage and promote tumor cell apoptosis. In addition, Bractoppin can also promote the apoptosis of ovarian cancer cell lines and inhibit the HR and NHEJ repair ability of tumor cells. We demonstrate the value of ovarian borderline tumor organoids in the exploration of molecular therapy drugs, and Bractoppin may be a valuable small molecule drug in the treatment of BOT.

Loss of RBPMS in ovarian cancer compromises the efficacy of EGFR inhibitor gefitinib through activating HER2/AKT/mTOR/P70S6K signaling

RBPMS may be a tumor suppressor in cancer, but its impact in modulation of drug sensitivity is unclear. This study aimed to investigate the regulatory role of RBPMS in cellular response to EGFR inhibitor gefitinib in ovarian cancer (OC). By western blotting assay, we revealed RBPMS was down-regulated in epithelial ovarian cancer tissues compared to normal control ovarian epithelial tissues. Overexpression of RBPMS inhibited cell viability and proliferation, and conferred gefitinib sensitivity, accompanied by reduced expression of p-EGFR, and vice versa. Proteomic analysis and flow cytometry experiments showed that RBPMS induced S-stage cell cycle arrest in gefitinib-treated OC cells. Co-IP assay suggested that HER2 was a downstream target of RBPMS, and RBPMS negatively regulated HER2 expression. HER2 counteracted the stimulation of RBPMS to cell growth blocking, gefitinib sensitivity and cell cycle arrest. We further demonstrated that RBPMS overexpression suppressed the activation of p-AKT, p-mTOR and p-P70S6K, which was rescued by up-regulation of HER2. The combination of AKT inhibitor MK2206 and gefitinib had a synergistic effect on OC cells with high level of RBPMS. In conclusion, through the direct inhibition of HER2/AKT/mTOR/P70S6K pathway, RBPMS may be a potential therapeutic target for improving gefitinib sensitivity in OC.

Silencing of lncRNA SNHG17 inhibits the tumorigenesis of epithelial ovarian cancer through regulation of miR-485-5p/AKT1 axis

Epithelial ovarian cancer (EOC) stands up for about 90% of ovarian cancer cases, which is the frequent cause of death among women. LncRNAs are involved in progression of EOC. Meanwhile, lncRNA SNHG17 was upregulated in EOC, while the detailed function of SNHG17 in EOC remains unclear. Protein and mRNA levels were assessed by western blot and RT-qPCR, respectively. The function of SNHG17 in EOC cells was tested by CCK-8, Ki-67 staining, flow cytometry and transwell assay. Dual luciferase was applied for assessing the relation among SNHG17, miR-485-5p and AKT1. Furthermore, in vivo experiments were applied to test the impact of SNHG17 in EOC. SNHG17 knockdown reduced the proliferation and promoted the apoptosis of EOC cells. Consistently, si-SNHG17 obviously reduced the invasion and epithelial-to-mesenchymal transition (EMT) process of EOC cells. MiR-485-5p was proved to be the target miRNA of SNHG17, and SNHG17 negatively regulated the level of miR-485-5p. MiR-485-5p inhibitor significantly abolished the anti-tumor impact of si-SNHG17 on EOC. AKT1 was identified to be targeted by miR-485-5p, and miR-485-5p negatively modulated AKT1 and p-mTOR levels. Moreover, miR-485-5p mimics reduced the proliferation, migration and promoted the apoptosis of EOC cells via targeting AKT1. Furthermore, si-SNHG17 markedly suppressed EOC growth in vivo. SNHG17 silencing inhibits the development of EOC via regulation of miR-485-5p/AKT1 axis. Thus, our study might supply a novel strategy against EOC.

TRAF4 promotes the malignant progression of high-grade serous ovarian cancer by activating YAP pathway

High-grade serous ovarian cancer (HGSOC) accounts for the majority of deaths caused by epithelial ovarian cancer. The specific molecular changes attributable to the pathogenesis of HGSOC are still largely unknown. TRAF4 has been identified to be up-regulated in certain cancers. However, the role and mechanism of TRAF4 in HGSOC remain unclear. In this study, we aim to explore the prognostic value and function of TRAF4 in HGSOC. Immunohistochemical staining and prognostic analysis were used to estimate the prognosis value of TRAF4 in HGSOC. Cell counting assays, colony formation assays, sphere formation assays and tumorigenic assays were used to explore the function of TRAF4 in ovarian cancer cells. Furthermore, RNA-seq, qPCR and western blotting were performed to investigate the molecular mechanism of TRAF4 in ovarian cancer cells. The results showed that TRAF4 was significantly higher expressed in ovarian cancer than normal ovarian epithelium. Moreover, high expression of TRAF4 was significantly associated with shorter overall survival and recurrence-free survival in HGSOC. Knockdown of TRAF4 significantly inhibited the proliferation and tumorigenicity of ovarian cancer cells, whereas overexpression of TRAF4 promoted the proliferation and tumorigenicity of ovarian cancer cells both in vitro and in vivo. Mechanistically, our study demonstrated that TRAF4 expression was positively correlated with the YAP pathway gene signatures, and the malignant progression induced by TRAF4 was inhibited after silencing YAP signaling by its selective inhibitor. In conclusion, our findings suggested that TRAF4 promoted the malignant progression of ovarian cancer cells by activating YAP pathway and might serve as a prognostic biomarker for HGSOC.

Inhibition of STAT3 reverses Taxol-resistance in ovarian cancer by down-regulating G6PD expression in vitro

Ovarian cancer is the eminent gynecological malignancy and chemoresistance remains a major reason for poor in ovarian cancer patients. Taxol has been proved as the most effective chemotherapeutic agent against ovarian cancer. However development of Taxol resistance remains a major problem. Here, we report that STAT3, directly activates pentose-phosphate pathway to exert pro-oncogenic effects on Taxol resistance of ovarian cancer. In addition, we found that STAT3, p-STAT3 and glucose-6-phosphate dehydrogenase (G6PD) protein levels are upregulated in Taxol resistant cell lines compared with Taxol sensitive cell lines. Furthermore, inhibition of STAT3 decreased G6PD mRNA expression level and enhanced the sensitivity of Taxol resistant cell to Taxol. Finally, we found that STAT3 directly binds to the G6PD promoter region and promotes the expression of G6PD at transcriptional level. Taken together, our data indicate that activation of STAT3 promotes ovarian cancer cell proliferation, colony formation, and Taxol resistance via augmenting G6PD expression and pentose-phosphate metabolism flux, which provides a potential therapeutic target that may improve prognosis by decreasing G6PD expression and enhancing Taxol-sensitivity.

OI inhibits development of ovarian cancer by blocking crosstalk between cancer cells and macrophages via HIF-1α pathway

Intraperitoneal implantation of ovarian cancer (OC) decreases the survival rate in clinical practice. However, there are still great deficiencies in the therapeutic strategies of inhibiting the metastasis of OC. Here, we showed that 4-octyl itaconate (OI, a cell-permeable itaconate derivative) treatment didn't influence the development of OC in vitro. Instead, OI treatment repressed the activation of peritoneal macrophages and downregulated the expression of proinflammatory factors in mice bearing OC. Besides, OI inhibited the angiogenesis of OC tissues by downregulating HIF-1α of OC that was induced by proinflammatory factors from activated macrophages. In conclusion, our findings demonstrate that OI suppresses metastasis of ovarian cancer by blocking crosstalk between cancer cells and macrophages via HIF-1α pathway, providing a potential therapeutic strategy for metastasis of OC.

The USP18-FBXO6 axis maintains the malignancy of ovarian cancer

Ubiquitin-specific protease 18 (USP18) is a deubiquitinating enzyme that reverses the post-translational modification of target proteins by ISG15 or ubiquitin, and is involved in a variety of cellular processes, including signal transduction, viral infection, and cancer development. Although high levels of USP18 mRNA have been observed in several types of cancer, its pathological significance in ovarian cancer (OV) is still elusive. Here, by integrating the Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO), and Genotypic Tissue Expression (GTEx) databases, we found that USP18 was abnormally up-regulated in OV tissues, and the increased expression of USP18 was associated with poor prognosis. We further showed that activated Jak-STAT3 signaling induced the expression of USP18, which in turn feedback maintained the activity of Jak-STAT3 signaling in OV. In addition, we found that USP18 played a cancer-promoting role in OV mainly through the transcriptional regulation of FBXO6. Silencing USP18 reduced the malignancy of OV, which can be largely reversed by overexpression of FBXO6. On the contrary, silencing FBXO6 significantly weaken the pro-proliferation function of USP18 in OV cells. In summary, our results indicate that USP18 is a downstream target gene of STAT3, and the USP18-FBXO6 axis might be a promising therapeutic target for OV.

Multi-component redox system for selective and potent antineoplastic activity towards ovarian cancer cells

Ovarian cancer is the deadliest gynecological cancer which rarely causes symptoms, and goes undetected until reaching the advanced stage of drug-resistant metastases. The cationic porphyrin meso-tetra(4-N-methylpyridyl)porphine (TMPyP) is a well-known photosensitizer (PS) used in photodyamic therapy (PDT) for curing cancer due to its strong affinity for DNA and high yield of reactive oxygen species (ROS) upon light activation. The practicality to irradiate tumor cells alone in the physiological system being slim (due to the close proximity of healthy cells and tumors), we looked for a variation in the PDT using a mixture of TMPyP with 1,5-dihydroxynapthalene (DHN) and Fe(III) ions at a mole ratio of 1:20:17 (drug combo) respectively in aqueous solution. The drug combo needs no photoactivation in H

MAP7 interacts with RC3H1 and cooperatively regulate cell-cycle progression of cervical cancer cells via activating the NF-κB signaling

Ensconsin is encoded by the MAP7 gene and belongs to the microtubule-associated proteins. This study aimed to explore its functional roles and partners in cell-cycle progression in cervical cancer. Data from the Cancer Genome Atlas-Cervical & Endocervical Cancer (TCGA-CESC) and the Genotype-Tissue Expression project were used for bioinformatic analysis. SiHa cells were used for in-vitro and in-vivo analysis. Co-immunoprecipitation (Co-IP) assay was conducted to explore the proteins interacted with MAP7. Results showed that MAP7 mRNA expression might serve as an independent biomarker of shorter survival. MAP7 overexpression elevated cyclin D1/cyclin B1 expression, facilitated cell-cycle progression and promoted SiHa cell growth in a xenograft tumor model. Co-IP experiments confirmed a novel interaction between MAP7 and RC3H1. Knockdown of either RC3H1 or MAP7 significantly attenuated cyclin D1/cyclin B1 upregulation, and cell-cycle progression induced by the other partner. MAP7 overexpression led to increased expression of P-IKK (Ser176/177) and P-p65 (Ser536). RC3H1 inhibition abrogated MAP7 induced upregulation of P-IKK and P-p65. Data in TCGA-CESC showed that MAP7 expression was positively correlated with its copy number segments, but was negatively correlated with the methylation level of three CpG sites within the gene locus. Demethylation treatment by 5-Aza-dC elevated both MAP7 mRNA and protein expression in a dose-dependent manner. In conclusion, this study revealed a novel interaction between MAP7 and RC3H1 in cervical cancer cells, which cooperatively enhanced cyclin D1/cyclin B1 expression and facilitated cell-cycle progression. These effects were at least partly mediated by activated canonical IKK/NF-kB signaling.

ERG the modulates Warburg effect and tumor progression in cervical cancer

Altered aerobic glycolysis is an important feature of cancer cell energy metabolism, known as the Warburg effect. Cervical cancer is one of the most common causes of cancer death in females. However, the roles of aerobic glycolysis in the development of cervical cancer are still poorly defined. Here, we identified a transcription factor (TF), ETS-related gene (ERG), as a new regulator of cancer progression and the glycolysis process in cervical cancer. In this study, we found that ectopic expression of ERG enhanced the capacity of aerobic glycolysis and increased glucose uptake, lactate production, and ATP generation. ERG overexpression increased and ERG knockdown decreased the anchorage independent cell growth and cell invasion in cervical cancer cells. Mechanistically, we propose that ERG regulates the expression of hexokinase 2 (HK2) and phosphoglycerate kinase 1 (PGK1) in the glycolytic pathway by directly binding to their promoters. A gain-of-function study showed that the knockdown or overexpression of HK2 and PGK1 abolished the increased or decreased aerobic glycolysis and cervical cancer progression induced by stable ectopic expression or depletion of ERG, respectively. Taken together, our findings suggest that ERG plays a potential role in the progression of cervical cancer, and could serve as a novel biomarker and potential therapeutic target in cervical cancer.

circ0000069 promotes cervical cancer cell proliferation and migration by inhibiting miR-4426

Circular RNAs (circRNAs) have been shown to be associated with the occurrence and development of cervical cancer (CC). In the present study, we aimed to investigate the tumor-promoting effect of hsa_circ_0000069 (circ0000069) on CC and the mechanisms underlying its effect. We found that circ0000069 was upregulated in CC cells and tissues, and that N6-methyladenosine (m6A) modification maintained circ0000069 stability. Gain- and loss-of-function assays revealed that circ0000069 promoted CC cell proliferation and migration. miR-4426 specifically binds circ0000069 and mediates its functions in CC development. In conclusion, circ0000069 was upregulated partially due to m6A modification, which promoted cell proliferation and migration via sponging miR-4426 in CC.

UCHL3 promotes cervical cancer development and metastasis by stabilizing NRF2 via deubiquitination

Cervical cancer is one of the most lethal gynaecological malignancies in females. The deubiquitylase UCHL3 has been studied as an oncogenic factor in multiple cancers. However, the expression pattern and function profile of UCHL3 in cervical cancer hasn't been fully characterized. Here, we revealed that UCHL3 was highly expressed in cervical cancer and overexpressed UCHL3 predicted a poor survival probability in cervical cancer patients. Our findings showed that knockdown of UCHL3 inhibited cell growth, migration and invasion in cervical cancer cells while UCHL3 knockdown inhibited cervical cancer development and metastasis in vivo in mouse models. Mechanistically, co-immunoprecipitation assay showed that UCHL3 directly interacted with NRF2. Knockdown of UCHL3 decreased NRF2 expression while overexpression of UCHL3 stabilized NRF2 via deubiquitination. In addition, overexpression of UCHL3 with C92A mutation didn't affect NRF2 stability. Moreover, we revealed that overexpression of NRF2 could antagonize the function of UCHL3 knockdown in cervical cancer cells. Collectively, our findings suggest that UCHL3 promotes cervical cancer development and metastasis by stabilizing NRF2 via deubiquitination. Thus, UCHL3/NRF2 axis could be utilized to develop efficient treatments for cervical cancer patients.

MEF2C-AS1 regulates its nearby gene MEF2C to mediate cervical cancer cell malignant phenotypes in vitro

Cervical cancer (CC) is the second most common malignancy among women. GEPIA demonstrated that MEF2C-AS1 and its nearby gene MEF2C present downregulation in CC tissues. We attempted to clarify molecular mechanism between MEF2C-AS1 and MEF2C underlying CC progression. RT-qPCR was used to measure expression levels and subcellular distribution of MEF2C-AS1 and MEF2C in CC cell lines. Gain-of-function assays were conducted to reveal roles of MEF2C-AS1 and MEF2C in CC cell behaviors. Bioinformatics, RNA pull down, and RIP assays were performed to assess association of MEF2C-AS1 or MEF2C with miR-20 b-5p in CC cells. Rescue assays were done to assess regulatory function of the MEF2C-AS1-miR-20 b-5p-MEF2C axis in CC cellular processes. MEF2C-AS1 and its nearby gene MEF2C showed downregulation and had a positive expression correlation in CC tissues. MEF2C-AS1 and MEF2C presented downregulation in CC cells, and they majorly distributed in CC cell cytoplasm. MEF2C-AS1 and MEF2C upregulation repressed CC cell proliferative, migratory, and angiogenic abilities. MEF2C-AS1 competitively bound with miR-20 b-5p to upregulate MEF2C in CC cells. The impacts of MEF2C-AS1 elevation on CC cell proliferative, migratory, and angiogenic capabilities were countervailed by miR-20 b-5p overexpression. The impacts of miR-20 b-5p inhibitor on CC cell proliferative, migratory and angiogenic capabilities were countervailed by MEF2C depletion. To sum up, MEF2C-AS1 and its nearby gene MEF2C present downregulation and serve as tumor suppressors in CC cells. MEF2C-AS1 suppresses CC cell malignancy in vitro through sponging miR-20 b-5p to upregulate MEF2C, which may provide a potential new direction for seeking therapeutic plans of CC.

Isoginkgetin as a novel USP8 inhibitor discovered by structure-based virtual screening exerts anticancer effects in ovarian cancer

Ubiquitin-specific protease 8 (USP8) gene has been identified as being significantly amplified and overexpressed in Ovarian carcinoma (OC), and thus led to unfavorable clinical outcomes, implying that inhibition of USP8 may be a therapeutic strategy for OC. Herein, a structure-based discovery and bioassays were conducted to identify novel inhibitors of USP8. we employed a novel platform that integrates docking/molecular dynamics (MD) simulation/binding free energy calculations/root-mean-square deviation (RMSD)/USP8 enzyme activity assay to screen a library of bioactive compounds including 30000 compounds. we identified that Isoginkgetin exhibited promising inhibitory activity on USP8 with an IC50 value of 12.68 μM. Moreover, Isoginkgetin could significantly inhibit OC cell growth by suppressing cell proliferation and reducing colony formation, and promoting Fe

Overcoming paclitaxel resistance in ovarian cancer cells using DN200434, an inverse agonist of estrogen-related receptor gamma (ERRγ)

Ovarian cancer is one of the most prevalent gynecological malignancies in women. Resistance towards frontline chemotherapy, paclitaxel is a major obstacle in the management of cancer. This intricate phenomenon reduces the treatment efficacy, leading to poor patient prognosis. Recently, the nuclear receptor estrogen-related receptor γ (ERRγ) has been implicated in cancer progression and metastasis. In particular, the receptor is reported to be overexpressed in ovarian cancer, and its overexpression is associated with reduced overall survival. However, the effect of ERRγ targeting using the selective inverse agonist DN200434 on ovarian cancer progression remains to be explored. In this study, we report dose-dependent inhibition of SKOV-3 progression and parallel induction of apoptosis with DN2000434. Further, the potential of receptor targeting in sensitization towards taxol is shown in resistant SKOV-3 cells. The combination of DN200434 and paclitaxel induced resistance reversal via augmentation of cell cycle arrest and apoptosis. This phenomenon was corroborated in a 3-D agarose-based spheroid model.

Ovarian cancer cell heterogeneity and paclitaxel response in vitro 2D and 3D cancer cell models and xenograft growth in the chicken chorioallantoic membrane (CAM)

Among gynecological malignancies, epithelial ovarian cancer (EOC) is the most lethal, comprising a heterogeneous group of diseases. Paclitaxel is a standard chemotherapeutic agent and an important option for EOC treatment. However, chemotherapy often fails, contributing to a high rate of EOC recurrence. One of the models that best explains the cellular heterogeneity, disease aggressiveness, chemoresistance, recurrence risk, and metastasis observed in ovarian tumors is the presence of cancer stem cells (CSCs). This study aimed to assess the phenotypic changes in three EOC cell lines (TOV-21G, SKOV-3, and OV-90) cultured in monolayer (MN) and tumorsphere (CSCs enrichment-TS) models. After treatment with paclitaxel, we studied different cell subpopulations by immunophenotyping using CSC markers (CD44/CD24) and mesenchymal markers (CD117/CD146). The relative expression of mRNAs (CASP8, TNFRSF10B, TP53, and BCL2) and miRNAs (miR-26a, miR-125b-5p, miR-181c, miR-17-5p, and miR-221) was evaluated by qPCR. In addition, we assessed the growth capacity of residual cells treated with paclitaxel using the chorioallantoic membrane (CAM) model to study disease relapse. After paclitaxel exposure, OV-90 TS and TOV-21G TS cells showed an increase in cell growth ability, while SKOV-3 MN cells maintained colony formation capability. SKOV-3 MN cells were enriched in the CSC-like subset (CD24

Therapeutic potential of silica nanoparticles, cisplatin, and quercetin on ovarian cancer: In vivo model

The present study evaluated the effect of silica nanoparticles, quercetin, and cisplatin against ovarian cancer. Cisplatin is a potent antineoplastic agent but has greater toxicity against cancer. Quercetin is a powerful flavonoid with remarkable anti-cancer activity due to its anti-apoptotic nature. Forty female albino rats were randomly divided into eight groups, with five rats per group. Group 1 (G1) was normal control, G2 received Carboxymethylcellulose; G3 was the normal control and treated with quercetin, G4 was given silica nanoparticles, G5 was treated with cisplatin. G6 was the tumor control. Tumor induction was done by 7, 12-dimethylbenz (a) anthracene (DMBA), G7 was treated with quercetin-cisplatin-silica nanoparticles, and in G8 quercetin-cisplatin silica nanoparticles were used to treat the induced tumor. Chemically synthesized silica nanoparticles were characterized by scanning electron microscopy (SEM), energy dispersive X-ray (EDX), and Fourier Transform Infrared (FTIR). After the treatment, animals were sacrificed and tested for biochemical and hormonal assays. G6 displayed increased body weight and a significant rise in CA125 as compared to G1. G6 also exhibited an altered hormonal profile, with a particular increase in estrogen, FSH, and testosterone, along with reduced LH and progesterone levels. Lipid profile, liver enzymes, and renal parameters (urea and creatinine) increased in G6, but G8 significantly ameliorated all damaging effects of DMBA as observed in G6. The current study revealed that silica nanoparticles combined with cisplatin and quercetin demonstrated greater protection against drastic changes induced by carcinogens in ovarian cancer mice models.

Oncolytic vaccinia virus harboring aphrocallistes vastus lectin exerts anti-tumor effects by directly oncolysis and inducing immune response through enhancing ROS in human ovarian cancer

Aphrocallistes vastus lectin (AVL) is a Ca

Neil 1 deficiency facilitates chemoresistance through upregulation of RAD18 expression in ovarian cancer stem cells

Over the past decades, cancer stem cells (CSCs) have emerged as a critical subset of tumor cells associated with tumor recurrence and resistance to chemotherapy. Understanding the mechanisms underlying CSC-mediated chemoresistance is imperative for improving cancer therapy outcomes. This study delves into the regulatory role of NEIL1, a DNA glycosylase, in chemoresistance in ovarian CSCs. We first observed a decreased expression of NEIL1 in ovarian CSCs, suggesting its potential involvement in CSC regulation. Using pan-cancer analysis, we confirmed the diminished NEIL1 expression in ovarian tumors compared to normal tissues. Furthermore, NEIL1 downregulation correlated with an increase in stemness markers and enrichment of CSCs, highlighting its role in modulating CSC phenotype. Further mechanistic investigation revealed an inverse correlation between NEIL1 and RAD18 expression in ovarian CSCs. NEIL1 depletion led to heightened RAD18 expression, promoting chemoresistance possibly via enhancing Translesion DNA Synthesis (TLS)-mediated DNA lesion bypass. Moreover, dowregulation of NEIL1 results in reduced DNA damage accumulation and suppressed apoptosis in ovarian cancer. Overall, our findings unveil a novel mechanism involving NEIL1 and RAD18 in regulating chemoresistance in ovarian CSCs. Targeting this NEIL1-RAD18 axis may offer promising therapeutic strategies for combating chemoresistance and improving ovarian cancer treatment outcomes.

Erianin induces ferroptosis in ovarian cancer cells by upregulating PDP2 and activating the JNK signaling pathway

Ovarian cancer remains the deadliest gynecologic malignancy. Erianin, a plant-derived compound with antitumor activity through inducing ferroptosis-an iron-dependent programmed cell death that has been shown in other contexts to enhance tumor sensitivity to chemotherapy-has not yet been fully explored in ovarian cancer. We therefore evaluated its anti-proliferative effects and underlying mechanism. Cell viability (CCK-8), cell death (Annexin V-FITC/PI flow cytometry, Western blot), and lipid peroxidation assays were performed in A2780 and ES-2 cells. Transcriptome (RNA-seq) and GO enrichment analyses identified signaling pathways, followed by mechanistic validation. Antitumor efficacy was verified in a nude-mouse xenograft model. Erianin exhibited a dose-dependent inhibitory effect on the proliferation of ovarian cancer cells A2780 and ES-2. Ferroptosis was identified as the primary mode of cell death, supported by a combination of evidence: (i) preferential rescue with the ferroptosis inhibitor Ferrostatin-1; (ii) characteristic molecular changes, including downregulation of key suppressors (GPX4, FTH1, SLC7A11) and upregulation of the pro-ferroptotic protein ACSL4; and (iii) elevated lipid peroxidation (MDA) and ROS alongside depleted GSH. Annexin V-FITC/PI flow cytometry was used to assess overall cell death patterns. Mechanistic studies showed that Erianin promoted ferroptosis via activation of the JNK signaling pathway and upregulation of PDP2 expression. In vivo, Erianin significantly suppressed tumor growth and induced molecular changes indicative of a less aggressive phenotype, including modulation of epithelial-mesenchymal transition (EMT) markers (increased E-cadherin, decreased N-cadherin). Erianin induces ferroptosis via PDP2-mediated activation of the JNK signaling pathway, thereby restraining ovarian cancer growth in vitro and in vivo. These findings provide a mechanistic rationale for further evaluation of Erianin as a ferroptosis-inducing therapeutic candidate, including in chemoresistant settings.

In silico and in vitro analysis: Unveiling the therapeutic potential of flavonoids against KLF7 in ovarian cancer

Ovarian cancer (OC) remains a major clinical challenge due to late-stage diagnosis, molecular heterogeneity, and the frequent development of chemoresistance, leading to poor patient outcomes. These challenges underscore the urgent need to identify transcriptional regulators that drive tumor progression and may serve as potential therapeutic targets. Krüppel-like factors (KLFs) are a family of transcription factors involved in regulating cellular proliferation, differentiation, apoptosis, and epithelial-mesenchymal transition (EMT). Among them, Krüppel-like factor 7 (KLF7) has been implicated as a tumor-promoting regulator in multiple malignancies, including OC. A full-length structural model of KLF7 obtained from the AlphaFold Protein Structure Database was used for structure-based analyses. Molecular docking and virtual screening were conducted to identify flavonoid compounds with high predicted binding affinity toward KLF7. ADMET analysis was performed to evaluate drug-likeness of compounds. The top-ranked compounds were further analyzed using molecular dynamics (MD) simulations and MM/GBSA calculations to assess complex stability and binding energetics. In vitro study of the most stable flavonoid with OC cell lines was performed to check the inhibitory efficacy. Hesperidin, and diosmin showed stable interactions with KLF7 and favorable binding energies during MD simulations. In vitro experiments demonstrated dose-dependent effects of hesperidin and diosmin on OC cells, indicating potential antiproliferative activity. These findings suggest that hesperidin and diosmin may interact with structurally relevant regions of KLF7 and could serve as potential lead compounds for further investigation.

SNRPD3 promotes endometrial cancer progression via regulating SREBF1 intron retention

Alternative splicing (AS) serves as a pivotal post-transcriptional regulatory mechanism that drives tumorigenesis. Small nuclear ribonucleoprotein D3 (SNRPD3), an indispensable component of the spliceosome, is aberrantly expressed in multiple malignancies. Nevertheless, its biological functions and underlying mechanisms in the pathobiology of endometrial cancer (EC) remains unknown. We demonstrated that SNRPD3 was significantly upregulated in human EC tissues. Knockdown of SNRPD3 markedly inhibited EC cell proliferation, migration, and invasion in vitro and suppressed tumor growth in subcutaneous xenograft models. Mechanistically, silencing SNRPD3 increased intron retention in SREBF1 mRNA. Furthermore, depletion of SREBF1 abolished the enhanced proliferative capacity and lipid metabolism in both parental EC cells and SNRPD3-overexpressing EC cells. Notably, antisense oligonucleotides (ASOs)-mediated silencing of SNRPD3 markedly repressed EC cell growth and metastatic potential in vitro, and effectively impeded tumor progression in patient-derived xenograft (PDX) models. Collectively, our findings reveal that SNRPD3 serves as an oncogenic splicing factor that promotes EC proliferation and metastasis by regulating SREBF1 mRNA splicing. Given its potent antitumor efficacy in preclinical PDX models, ASO-targeted SNRPD3 may represent a promising therapeutic strategy for endometrial cancer.

Proteasome inhibition by bortezomib induces stress-response–mediated cytotoxicity in uterine leiomyosarcoma cells

Uterine leiomyosarcoma (Ut-LMS) is a rare and aggressive gynecologic malignancy with limited effective therapeutic options. In this study, we investigated the cytotoxic effects and underlying mechanisms of bortezomib in Ut-LMS cell lines SK-LMS-1 and SK-UT-1B. Bortezomib treatment significantly reduced cell viability and increased lactate dehydrogenase release, indicating pronounced cytotoxicity. Apoptotic cell death was induced, as evidenced by increased Annexin V-positive cell populations. Bortezomib also suppressed proliferative activity, reflected by reduced Ki67 expression, and induced G2/M cell cycle arrest in SK-LMS-1 cells, whereas SK-UT-1B cells exhibited minimal alterations in cell cycle distribution. In addition, bortezomib increased reactive oxygen species production in SK-UT-1B cells and induced mitochondrial membrane depolarization in both cell lines, while antioxidant treatment attenuated bortezomib-induced apoptosis in SK-UT-1B cells, indicating partial involvement of oxidative stress. Western blot analysis further revealed enhanced cleavage of poly(ADP-ribose) polymerase and caspase-3, along with modulation of cell cycle regulatory proteins, including upregulation of p21 and differential regulation of p53 between the two cell lines. Finally, autophagy-related analyses demonstrated increased LC3B-II levels accompanied by p62 accumulation, suggesting altered autophagic processing rather than simple activation of autophagy. Collectively, these findings demonstrate that bortezomib exerts cytotoxic effects in Ut-LMS cells through coordinated regulation of proteasome inhibition-associated apoptosis, cell cycle control, mitochondrial dysfunction, and autophagy-related signaling, with cell line-specific differences in stress response pathways.

Targeting RNF8 effectively reverses cisplatin and doxorubicin resistance in endometrial cancer

Endometrial cancer (EC) is one of the most frequent gynecological malignancy worldwide. However, resistance to chemotherapy remains one of the major difficulties in the treatment of EC. Thus, there is an urgent requirement to understand mechanisms of chemoresistance and identify novel regimens for patients with EC. We found that protein and mRNA expression levels of RNF8 were significantly increased in both cisplatin and doxorubicin resistant EC cells. Cell survival assay showed that RNF deficiency significantly enhanced the sensitivity of resistant EC cells to cisplatin and doxorubicin (P < 0.01). In addition, chemoresistant EC cells exhibited increased NHEJ efficiency. Knockout of RNF8 in chemoresistant EC cells significantly reduced NHEJ efficiency and prolonged Ku80 retention on DSB. Moreover, cisplatin resistant AN3CA xenograft showed that RNF8 deficiency overcame cisplatin resistance. Our in vitro and in vivo assays provide evidence for RNF8, which is a NHEJ factor, serving as a promising, novel target in EC chemotherapy.

Integrated network pharmacology and experimental models uncover the mechanism of procyanidin B2 against ovarian carcinoma via EGFR/AKT pathway

Ovarian carcinoma (OC) remains a lethal malignancy with limited therapeutic options. Procyanidin B2, a natural flavonoid, has demonstrated broad bioactivity, yet its potential role in ovarian cancer remains incompletely understood. This study employed an integrated approach combining network pharmacology, molecular docking, and experimental validation to elucidate the anti-tumor mechanisms of Procyanidin B2 in ovarian cancer. Through multi-database screening, 97 potential targets of Procyanidin B2 related to OC were identified. Functional enrichment analyses highlighted significant involvement in cancer-related pathways such as PI3K-Akt, HIF-1 and EGFR tyrosine kinase inhibitor resistance. Protein-protein interaction network analysis identified 10 hub genes, among which EGFR and AKT1 were prioritized. Molecular docking confirmed strong binding interactions between Procyanidin B2 and these targets, particularly EGFR. In vitro assays revealed that Procyanidin B2 selectively inhibited proliferation and colony formation, and induced apoptosis in A2780 and SKOV3 cells, accompanied by upregulation of cleaved caspase-3 and suppression of phosphorylated EGFR and AKT. In a xenograft model, Procyanidin B2 administration significantly suppressed tumor growth without evident toxicity, consistent with the in vitro signaling alterations. These results suggest that Procyanidin B2 exerts anti-ovarian cancer effects partly through modulating the EGFR/AKT signaling axis, supporting its potential as a complementary therapeutic candidate.

Physicochemical characterization and anticancer potential of Ficus deltoidea-silver nanoparticles (FD-AgNPs) on HeLa cells: Evidence from apoptosis and proliferation assays

Cervical cancer remains a major global health challenge, accounting for more than 660,000 new cases and 350,000 deaths worldwide in 2022. In this study, silver nanoparticles biosynthesized using Ficus deltoidea leaf extract (FD-AgNPs) were developed and evaluated for their anticancer potential against HeLa cervical cancer cells. Physicochemical characterization confirmed successful nanoparticle formation, with UV-Vis absorption peaks at 420-460 nm, FTIR spectra indicating phytochemical-mediated reduction and capping, and XRD analysis revealing a highly crystalline face-centered cubic structure. TEM imaging showed predominantly spherical nanoparticles with an average crystallite size of 21.01 nm, while zeta potential (-21.8 mV) and DLS (∼75 nm) measurements suggested moderate colloidal stability. Functionally, FD-AgNPs significantly decreased HeLa cell viability in a dose-dependent manner (p < 0.001), exhibiting stronger cytotoxic effects at 5 and 10 μg/mL than cisplatin. Treated cells displayed marked morphological alterations consistent with activation of intrinsic apoptotic pathways, which was further supported by a significant increase in cleaved caspase-3 expression at both concentrations (p < 0.0001). In addition to apoptosis induction, FD-AgNPs effectively suppressed cancer cell proliferation, as evidenced by significant downregulation of pAKT and Ki-67 expression (p < 0.001), indicating interference with AKT-mediated survival and cell cycle signaling. Overall, these findings demonstrate that FD-AgNPs exert potent anticancer effects by simultaneously inhibiting proliferation and promoting apoptosis in cervical cancer cells. The integration of green synthesis, detailed physicochemical characterization, and mechanistic biological evaluation underscores the potential of FD-AgNPs as a promising plant-based nanotherapeutic approach for cervical cancer treatment.

Multifaceted computational insights of murrayacinine as dual inhibitors of CDK2 and MAPK3 to combat cervical cancer

Cervical cancer, the fourth most common cancer among women, and the reported anti-cancer properties of Bergera koenigii prompted this study to explore its therapeutic potential using advanced computational approaches. From a curated library of 394 phytochemicals, a subset of 153 compounds was selected based on initial screening and subsequently evaluated for drug-likeness and ADMET properties. Protein-protein interaction analysis identified 15 key hub genes from 99 drug-disease targets, particularly in pathways related to Human papillomavirus infection. Molecular docking showed that Isomahanine, (+)-Mahanimbicine, and Murrayacinine bound CDK2 and MAPK3 more strongly than Topotecan. All tested compounds had similar affinities for CDK2 (-10.8 to -10.6 kcal/mol) and MAPK3 (-10.8 to -10.5 kcal/mol), while Topotecan showed weaker binding with values of -9.6 kcal/mol for CDK2 and -9.1 kcal/mol for MAPK3. Moreover, Murrayacinine exhibited the most stable binding with CDK2 and MAPK3, showing the lowest RMSD, RMSF, and Rg values, while (+)-Mahanimbicine had the highest fluctuations, and Topotecan showed moderate stability. Additionally, Murrayacinine exhibited the lowest SASA and the highest HBs, confirming its superior binding stability over Topotecan and other phytochemicals, during MD simulation (300 ns) analysis. Protein-ligand distance, pairwise RMSD, and PCA analyses further confirmed the superior structural stability of Murrayacinine. The MM/GBSA analysis confirmed strong interactions between Murrayacinine and target proteins CDK2 and MAPK3 with corresponding binding free energies (-29.6 and -25.1 kcal/mol), compared to Topotecan (-20.9 and -18.1 kcal/mol). Overall, Murrayacinine exhibited higher potency against cervical cancer through its multitargeted action, highlighting B. koenigii phytochemicals as promising drug candidates for treatment.

Hsa_circ_0000585 promotes chemoresistance to cis-platin in epithelial cells of ovarian cancer by modulating autophagy

Chemoresistance, i.e., resistance to cisplatin (DDP), has been a major obstacle to ovarian cancer treatment. It has been found that circular RNAs (circRNAs) play vital roles in the tumorigenesis various cancers by regulating autophagy, while few studies focusing on cisplatin-resistance ovarian cancer (CROC). The expressions of the circRNAs were detected by qRT-PCR. Short hairpin RNA targeting circRNA was used to explore the biological functions of the circRNA. Cell viability, autophagic flux, immunofluorescence, and xenograft tumors experiments were performed to further illustrate the underlying mechanisms. Hsa_circ_0000585 was increased in cisplatin-resistant SKOV3/DDP cells. Stably knocking down hsa_circRNA_0000585 expression in SKOV3/DDP cells was established by RNA interference. We found that downregulation of hsa_circ_0000585 significantly enhanced the sensitivity of DDP/SkOV3 cells to DDP. In vivo study, hsa_circRNA_0000585 knockdown significantly decreased tumor volume in nude mice. Under the measurements of western blot and cellular immunofluorescence, hsa_circ_0000585 knockdown significantly inhibited the expression of Beclin1 and P62, indicating the autophagic flux was inhibited. Administrations with autophagic inhibitor "Chloroquine (CQ)" and autophagy activator "QX77" further confirmed that hsa_circ_0000585 knockdown resulted in autophagy inhibition. Overall, this study provided a new insight into the role of circRNAs in the mechanism of DDP-resistance in ovarian cancer. Hsa_circRNA_0000585 may be promising therapeutic targets for the enhancement of the sensitivity of ovarian cancer cells to cisplatin-mediated chemotherapy.

TAK-981 enhances antitumor activity in ELT3 uterine leiomyoma cells through the modulation of apoptosis, cell cycle arrest, and autophagy

Uterine leiomyomas, commonly known as fibroids, are the most prevalent benign tumors in women of reproductive age and are characterized by abnormal smooth muscle cell proliferation in the uterine wall. TAK-981 (subasumstat), an investigational drug that inhibits SUMOylation by targeting SUMO-activating enzymes, has demonstrated high potential for the treatment of various cancers. However, its effects on uterine leiomyomas remain largely unexplored. In this study, we evaluated the therapeutic effects of TAK-981 on ELT3 uterine leiomyoma cells. TAK-981 significantly decreased the viability of ELT3 uterine leiomyoma cells and inhibited colony formation. It also induced apoptosis and caused G2/M phase cell cycle arrest, demonstrating a strong effect on cell proliferation and survival. Notably, although TAK-981 enhances reactive oxygen species production, it also induces apoptosis through a reactive oxygen species-independent mechanism, as evidenced by increased apoptosis rates upon co-treatment with antioxidants such as N-acetylcysteine. Furthermore, western blot analysis revealed that treatment with TAK-981 downregulated MEK-1 expression and inhibited ERK phosphorylation, leading to enhanced cleavage of caspase-3 and PARP, thereby promoting apoptosis in ELT3 cells. Additionally, TAK-981 reduced extracellular matrix accumulation by suppressing Collagen I and Acta2 expression and promoted autophagy in ELT3 cells, as indicated by increased levels of LC3. These findings suggest that TAK-981 can be used as a therapeutic option for managing uterine leiomyomas through multiple mechanisms, including apoptosis induction and autophagy promotion.

Integrin α1 upregulation by TF:FVIIa complex promotes cervical cancer migration through PAR2-dependent MEK1/2 activation

Tissue factor (TF) and protease-activated receptor 2 (PAR2) have been associated with the progression of cancer, while integrins are essential for the adhesion and migration of cancer cells. This study aimed to explore the cross-talk between the TF:FVIIa complex, PAR2 signaling, and the expression of integrin α1 in cervical cancer cells. Utilizing data from The Cancer Genome Atlas (TCGA), the research examined the relationship between the TF and PAR2 genes and the integrin α1 gene (ITGA1) in reproductive cancers, revealing a positive correlation between integrin α1 expression and both TF and PAR2 genes. Analyses through Western blotting and RT-PCR demonstrated that TF:FVIIa complex transactivates PAR2, which significantly increases the phosphorylation of MEK1/2 and subsequently elevates integrin α1 expression. Inhibition of either PAR2 or MEK1/2 resulted in a decrease in the FVIIa-induced increase in integrin α1 expression. Additionally, cell migration studies indicated that elevated expression of integrin α1, mediated by the TF:FVIIa/PAR2 pathway, was linked to enhanced cell migration, which could be inhibited by blocking integrin α1. This investigation uncovers a novel signaling pathway in HeLa cells, highlighting the significance of the TF:FVIIa:PAR2 axis in modulating integrins that are vital for cancer progression, thereby offering insights for potential targeted therapeutic approaches in cancer treatment.

The characterization of the sensitive ovarian cancer cell lines A2780 and W1 in response to ovarian CAFs

The cancer-associated fibroblasts (CAFs) are one of the most abundant components of the tumor microenvironment (TME). CAFs have been implicated in tumor progression, extracellular matrix (ECM) remodeling, and treatment resistance. Drug resistance is the primary limiting factor in achieving cures for patients with cancer, particularly ovarian cancer. Therefore, inhibiting CAFs can be an effective strategies for cancer treatment. In this research, we studied whether CAFs have an influence on drug-sensitive ovarian cancer cells to become more resistant. We examined the influence of CAFs on genes and proteins expression changes in sensitive ovarian cancer cells. We prepared a 3D co-culture to investigate the role of CAFs on cancer cell morphology. Here, we performed a detailed analysis of drug-sensitive ovarian cancer cell lines (A2780 and W1) and the influence of ovarian CAFs on the A2780 and W1 cells morphology, genes and proteins expression. The 2D and 3D cultures, genes expression analysis (TaqMan qPCR), and proteins expression (Western blot analysis) were assessed in this study. We observed upregulation of ABCC5, CYP2C8, CYP2C9, and DHFR mRNA in cell lines supplemented by CAFs medium. We showed fibronectin overexpression and COL3A1 downregulation after supplementation with CAFs. Co-culturing with CAFs prevented the formation of spheroids in 3D conditions. We demonstrated that the process of drug resistance in ovarian cancer cells is launched by CAFs. CAFs not only simulate cancer cells to produce drug transporters and specific enzymes production, but also remodel the TME to increase drug resistance. We believe that cancer progression and migration is due to the CAFs po-tumorigenic activity.

The role of Connexin26 regulated by MiR-2114-3p in the pathogenesis of ovarian cancer

The purpose of our research was to determine the expression of Cx26 and miR-2114-3p, and their effects on proliferation, migration, and invasion in ovarian cancer and their mechanisms. Transcriptome sequencing was performed and differentially expressed Cx26 was screened. The mRNA and protein levels of Cx26 in EOC and normal ovarian tissues were verified. The relationship between Cx26 levels and prognostics was analyzed. Cx26 Lentiviral vectors were constructed to detect its effect on ovarian cancer. WB verified that PI3K/AKT pathway was the possible signal pathway regulated by Cx26. The interaction between miR-2114-3p and Cx26 was detected by double luciferase reporter assay and qrt-PCR. CCK8, clone formation, transwell, and flow cytometry assays were conducted in cells transfected miR-2114-3p plasmids. The vivo experiment investigated the effects of Cx26 on subcutaneous tumor growth, PI3K expression, proliferation proteins Ki67 and PCNA. Cx26 was up-regulated in EOC tissue and cell lines, and was associated with poor prognosis of ovarian cancer, while miR-2114-3p was down-regulated in EOC cell lines. Cx26 was a direct target of miR-2114-3p. Cx26 overexpression and miR-2114-3p inhibition promoted the growth, motility, invasiveness, and S phase arrest of EOC cells. Additionally, Cx26 could activated PI3K pathway whatever in vivo and in vitro. Dysregulation of Cx26 is critical in EOC patients. Manipulation of this mechanism may influence the survival of EOC patients. MiR-2114-3p regulates the tumor-promoting activity of Cx26 in EOC. By inhibiting the PI3K pathway or knocking down Cx26 effectively inhibits tumor growth in EOC cells and Nude mouse model.

Circ0004390 promotes cell proliferation through sponging miR-198 in ovarian cancer

Circular RNAs (circRNAs) are a novel class of non-coding RNAs which play important roles in human diseases and tumor progression. However, the function of circRNAs in ovarian cancer remains to be uncovered. Here we found a large amount of circRNAs that are differentially expressed in ovarian cancer tissues compared with normal ovarian tissues. We further identified one circRNA derived from the LPAR3 gene and termed Circ0004390, which was frequently upregulated in ovarian cancer tissues. The knockdown of Circ0004390 can significantly reduce the proliferation of ovarian cancer cells. We further demonstrated that Circ0004390 may promote cell proliferation by acting as a sponge for the miR-198 family to regulated the MET expression in ovarian cancer cells. The level of Circ0004390 was closely related with overall survival of ovarian cancer patients. Our findings suggested that Circ0004390 regulated ovarian cancer proliferation by miR-198/MET axis, which might provide a potential target for the treatment of ovarian cancer.

CAFs-derived exosomes promote the development of cervical cancer by regulating miR-18a-5p-TMEM170B signaling axis

Mounting studies have showed that tumor microenvironment (TME) is crucial for cervical cancer (CC), and cancer-related fibroblasts (CAFs) play a major role in it. Recently, exosomal miRNAs secreted by CAFs have been found to be potential targets for cancer diagnosis and therapy. In this paper, we aimed to investigate the function of CAFs-mediated exosome miR-18a-5p (CAFs-exo-miR-18a-5p) in CC. First, in combination with bioinformatic data analysis of the GEO database (GSE86100) and RT-qPCR of CC clinical tissue samples and cell lines, miR-18a-5p was discovered to be markedly up-regulated in CC. Next, CAFs-secreted exosomes were isolated and it was found that miR-18a-5p expression was dramatically promoted in CC cell lines when treated with CAFs-exos. The CAFs-exo-miR-18a-5p was then elucidated to stimulate the proliferation and migration and inhibit the apoptosis of CC cells. In order to clarify the underlying mechanism, we further screened the target genes of miR-18a-5p. TMEM170B was selected by bioinformatic data analysis of online databases combined with RT-qPCR of CC clinical tissues and cells. Luciferase reporter gene analysis combined with molecular biology experiments further elucidated that miR-18a-5p suppressed TMEM170B expression in CC. Finally, both cell and animal experiments demonstrated that TMEM170B over-expression attenuated the oncogenic effect of CAFs-exo-miR-18a-5p. In conclusion, our study indicates that CAFs-mediated exosome miR-18a-5p promotes the initiation and development of CC by suppressing TMEM170B signaling axis, which provides a possible direction for the diagnosis and therapy of CC.

EMT-inducing transcription factor ZEB1-associated resistance to the BCL-2/BCL-XL inhibitor is overcome by BIM upregulation in ovarian clear cell carcinoma cells

Ovarian clear cell carcinoma (OCCC) is an aggressive subtype of epithelial ovarian cancer, which generally exhibits chemoresistance. Effective therapy for OCCC is currently unavailable, requiring the development of new therapeutic strategies. ABT-263 (navitoclax), an inhibitor of the anti-apoptotic BCL-2/BCL-X

Depletion of UBE2C reduces ovarian cancer malignancy and reverses cisplatin resistance via downregulating CDK1

Ovarian cancer is the most lethal gynecological malignancy, but the mechanisms of ovarian cancer progression and cisplatin resistance remain unclear. Emerging evidence suggested that ubiquitin-conjugating enzyme E2C (UBE2C) was highly expressed in a variety of tumors and acted as an oncogene. In our study, we demonstrated that UBE2C was overexpressed in ovarian cancer by immunohistochemistry (IHC) and The Cancer Genome Atlas (TCGA) database analysis. It was also found that high levels of UBE2C expression predicted worse clinical outcomes in ovarian cancer. After knocking down UBE2C, SKOV3 and A2780 cells showed inhibitory cell proliferation, increased apoptosis by blocking G2/M transition in vitro and in vivo. Besides, the downregulation of UBE2C reversed the cisplatin resistance states of SKOV3/DDP and A2780/DDP cells. Interestingly, CDK1 expression was also downregulated in UBE2C depleted ovarian cancer cells. Furthermore, we found that UBE2C expression was highly correlated with CDK1 expression in ovarian cancer tissues and cell lines, indicating that UBE2C might cooperate with CDK1 in ovarian tumorigenesis. Collectively, our findings strongly supported UBE2C as a candidate oncogene and a potential target for the treatment of ovarian cancer.

USP14 regulates heme metabolism and ovarian cancer invasion through BACH1 deubiquitination and stabilization

The deubiquitinating enzyme USP14 has been established as a crucial regulator in various diseases, including tumors, neurodegenerative diseases, and metabolic diseases, through its ability to stabilize its substrate proteins. Our group has utilized proteomic techniques to identify new potential substrate proteins for USP14, however, the underlying signaling pathways regulated by USP14 remain largely unknown. Here, we demonstrate the key role of USP14 in both heme metabolism and tumor invasion by stabilizing the protein BACH1. The cellular oxidative stress response factor NRF2 regulates antioxidant protein expression through binding to the antioxidant response element (ARE). BACH1 can compete with NRF2 for ARE binding, leading to the inhibition of the expression of antioxidant genes, including HMOX-1. Activated NRF2 also inhibits the degradation of BACH1, promoting cancer cell invasion and metastasis. Our findings showed a positive correlation between USP14 expression and NRF2 expression in various cancer tissues from the TCGA database and normal tissues from the GTEx database. Furthermore, activated NRF2 was found to increase USP14 expression in ovarian cancer (OV) cells. The overexpression of USP14 was observed to inhibit HMOX1 expression, while USP14 knockdown had the opposite effect, suggesting a role for USP14 in regulating heme metabolism. The depletion of BACH1 or inhibition of heme oxygenase 1 (coded by HMOX-1) was also found to significantly impair USP14-dependent OV cell invasion. In conclusion, our results highlight the importance of the NRF2-USP14-BACH1 axis in regulating OV cell invasion and heme metabolism, providing evidence for its potential as a therapeutic target in related diseases.

VSTM2L contributes to anoikis resistance and acts as a novel biomarker for metastasis and clinical outcome in ovarian cancer

The majority of patients are diagnosed when ovarian cancer (OC) has metastasized, making surgery and chemotherapy less effective. Thus, there is an urgent need to elucidate the mechanisms underlying metastasis and to further explore novel diagnostic biomarkers of OC metastasis. Here, we conducted a genome-wide CRISPR-Cas9 screen for anoikis resistance to identify key genes associated with OC metastasis. Further, bioinformatic analysis was performed using TCGA and GTEx datasets to explore the genes associated with OC progression and prognosis. After integrated analysis, the V-set and transmembrane domain-containing protein 2-like (VSTM2L) was identified as a crucial gene closely associated with OC metastasis, progression, and prognosis. Further validation using a patient-based cohort suggested that VSTM2L expression was significantly higher in metastatic lesions than in primary lesions. Subsequently, an in vitro assay showed that VSTM2L silencing increased SKOV3 cell death and hampered spheroid formation. Mechanistically, GSEA highlighted that epithelial-mesenchymal transition (EMT)-related pathways was positively associated with VSTM2L expression. Consistently, the validation based on the VSTM2L silence suggested the involvement of VSTM2L in EMT-related TGF-β and NF-κB signaling. Meanwhile, the addition of VSTM2L-containing medium did not provoke those signaling, indicating VSTM2L functions as an intracellular protein to activate TGF-β and NF-κB signaling. In summary, our study revealed that VSTM2L is a novel player involved in anoikis resistance and is a promising biomarker of OC metastasis and prognosis.

LSR promotes epithelial ovarian cancer cell survival under energy stress through the LKB1-AMPK pathway

Lipolysis-stimulated lipoprotein receptor (LSR), also known as a component of tricellular tight junctions, is highly expressing in epithelial ovarian cancer (EOC). However, the biological role of LSR in EOC cells remains unclear. In this study, we evaluated liver kinase B1 (LKB1) mediated AMP-activated protein kinase (AMPK) activity and investigated the effect of LSR on EOC cell survival under energy stress. LSR increased the levels of phospho-AMPKα at Thr172 and phospho-acetyl-CoA carboxylase (ACC) at Ser79 via LKB1-AMPK pathway in glucose deprivation in vitro. The increase of P-AMPKα (Thr172) and P-ACC (Ser79) was also detected in tumor microenvironment in vivo. Meanwhile, LSR promoted LKB1 localization at the cell membrane of EOC cells. By cell survival analysis, LSR attenuated glucose deprivation-induced cell death in EOC cells in vitro. Our results suggest that LSR promotes EOC cell survival and tumor growth through the LKB1-AMPK pathway.

LINC01133 contribute to epithelial ovarian cancer metastasis by regulating miR-495-3p/TPD52 axis

Currently, there is increasing evidence that long noncoding RNAs (lncRNAs) initiate and promote the progression of epithelial ovarian cancer (EOC). In this study, we revealed the roles and the potential mechanisms of long intergenic non-protein coding RNA 1133 (LINC01133) in EOC, which remains not well understood. We found that LINC01133 was upregulated in EOC tissues and cell lines. Besides, it was associated with the clinicopathological feature of metastasis. Functional experiments demonstrated that LINC01133 could facilitate cancer cell migration and invasion in vitro and tumor metastasis in vivo. Further molecular mechanisms studies indicated that LINC01133 and miR-495-3p reciprocally repressed expression of each other. We also realized that LINC01133 shared the same binding sites for miR-495-3p with tumor protein D52 (TPD52). We confirmed that TPD52 functioned as a direct target of miR-495-3p and mediated the enhancing effect of LINC01133 on cancer metastasis. Generally, our study showed that LINC01133 interacted with miR-495-3p to promote metastasis in EOC by regulating TPD52. LINC01133 also provided a potential therapeutic perspective for future clinical treatment.

Suppression of ovarian cancer by low-intensity ultrasound through depletion of IL-6/STAT3 inflammatory pathway-maintained cancer stemness

Ovarian carcinoma is the key cause of cancer death from gynecological malignancy of women. Chemotherapy-resistance, metastasis and relapse contribute to the high mortality in ovarian cancer patients. Cancer stem cells (CSCs) stand for the root of kinds of cancer types such as ovarian cancer, are the key driver of tumor initiation, cancer metastasis, and resistance to conventional chemotherapy as well as genomic targeted therapy. Thus, the approach to eliminate CSCs and uncovering the mechanism will have substantial impact on cancer therapy. However, targeting CSC remains unfeasible in clinical practice in ovarian cancer therapy. In this study, we first found that Low-intensity ultrasound (LIUS) was capable of reducing the CSC populations in the xenograft model with ovarian cancer, with blocking survival, anti-apoptosis, self-renewal, and downregulating the cancer stemness genes in ovarian CSCs. Moreover, LIUS ameliorated IL-6/STAT3 inflammatory pathway via inhibiting IL-6-induced STAT3 phosphorylation, DNA binding activity and, the expressions of its downstream effectors in ovarian CSCs while no explicit effect was found in the corresponding bulk cancer cells. Additional approaches in molecular studies showed that LIUS disrupts CSC features via inhibiting IL-6/STAT3 inflammatory pathway. Collectively, our data for the first time elucidate IL-6/STAT3 inflammatory loop as the key CSC or cancer stemness pathway in ovarian cancer by LIUS treatment, providing a novel and potential therapy and a promising target in ovarian cancer.

Ubiquitin specific peptidase 32 acts as an oncogene in epithelial ovarian cancer by deubiquitylating farnesyl-diphosphate farnesyltransferase 1

Epithelial ovarian cancer (EOC) is the seventh most common cancer worldwide and the deadliest gynecological malignancy because of its aggressiveness and high recurrence rate. To discover new therapeutic targets for EOC, we combined public EOC microarray datasets with our previous in vivo shRNA screening dataset. The top-ranked gene ubiquitin specific peptidase 32 (USP32), coding a deubiquitinating enzyme, is a component of the ubiquitin proteasome system. Clinically, USP32 is expressed in primary ovarian cancer, especially in metastatic peritoneal tumors, and negatively impacts the survival outcome. USP32 regulates proliferative and epithelial mesenchymal transition capacities that are associated with EOC progression. Proteomic analysis identified farnesyl-diphosphate farnesyltransferase 1 (FDFT1) as a novel substrate of USP32 that is an enzyme in the mevalonate pathway, essentially associated with cell proliferation and stemness. USP32 and FDFT1 expression was higher in tumor spheres than in adherent cells. Inhibition of USP32, FDFT1, or mevalonate pathway considerably suppressed tumor sphere formation, which was restored by adding squalene, a downstream product of FDFT1. These findings suggested that USP32-FDFT1 axis contributes to EOC progression, and could be novel therapeutic targets for EOC treatment.

Single-cell transcriptional profiling identifies a cluster of potential metastasis-associated UBE2C+ cells in immature ovarian teratoma

To dissect the disease heterogeneity and identify the underlying cellular and molecular events related to metastasis of immature ovarian teratoma in children, single-cell RNA sequencing was performed for a 2-year-old patient with liver metastases from immature ovarian teratoma. A total of 5976 cells were obtained for further analysis, with a median unique molecular identifier count of 6011 per cell and a median number of 1741 genes detected per cell. Fourteen clusters were recognized, with the main lineages comprising epithelial cells, macrophages, fibroblasts, glial cells, and dendritic cells. Ten subclusters of epithelial cells were further defined, originating from the urinary tract, esophagus, bronchus, lung, skin, and gastrointestinal tract. An undefined UBE2C + population in an active state of proliferation was also identified and its biological processes were related to meiosis and maturation of oocytes. Pseudotime analysis revealed different distributions of epithelial cells in the development trajectory. In conclusion, a cluster of UBE2C + epithelial cells in an active state of proliferation was identified in an immature ovarian teratoma in a child, and may contribute to metastasis by regulating epithelial-mesenchymal transition. These findings help toward understanding the origin of the malignant behaviors, offer a potential biomarker for early determination of the tumor nature, and provide new ideas for the therapy of immature ovarian teratoma in children.

Exploring the potential of engineered exosomes as delivery systems for tumor-suppressor microRNA replacement therapy in ovarian cancer

MicroRNA (miRNA) plays a pivotal role in cancer biology. Therefore, tumor suppressor (TS) miRNAs are an attractive target for cancer therapy. However, clinical trials have failed due to the difficulties in miRNA delivery, warranting the development of a novel drug delivery system (DDS). Exosomes are stable in circulation and selectively picked up by cancer cells, indicating that they can serve as a miRNA carrier. The aim of this study was to explore the possibility of exosomes as a carrier for miRNA replacement therapy for ovarian cancer (OC). First, exosomes were purified from primary-cultured omental fibroblasts of OC patients. miR-199a-3p was selected as a TS miRNA, and the synthesized miR-199a-3p was loaded into exosomes by electroporation. Treatment with miR199a-3p-loaded-exosomes (miR-199a-3p-Exo) drastically increased miR-199a-3p expression level in OC cell lines (CaOV3; 8592-, SKOV3; 67188-, and OVCAR3; 2280-fold). miR-199a-3p-Exo suppressed c-Met expression, a direct target of miR-199a-3p, and thereby inhibited cell proliferation and invasion. In a xenograft study, miR-199a-3p-Exo also drastically inhibited peritoneal dissemination in OC mice model, and diminished c-Met expression, ERK phosphorylation, and MMP2 expression in tumors. These results suggest that miRNA replacement therapy using exosomes shows promise for treatment of OC. Given that omental fibroblasts can be obtained from most OC patients, patient-derived exosomes can be utilized as a DDS for future molecular-targeted therapies.

LncRNA TLR8-AS1 promotes metastasis and chemoresistance of ovarian cancer through enhancing TLR8 mRNA stability

Ovarian cancer is diagnosed as the most deadly gynecological tumor. Ovarian cancer metastasis affects chemoresistance and confers poor patient prognosis. In present work, we intended to elucidate whether long non-coding RNAs (lncRNAs) TLR8-AS1 regulated cell metastasis and chemoresistance of ovarian cancer, and uncover the molecular mechanism of TLR8-AS1 in the modulation of ovarian cancer progression. Firstly, bioinformatics analyses identified TLR8-AS1 as a cancer-associated fibroblasts regulated lncRNA in ovarian cancer. Further experiments revealed that TLR8-AS1 augmented cell metastasis and chemoresistance of ovarian cancer in vitro and in vivo. Moreover, TLR8-AS1 upregulates TLR8 by stabilizing TLR8 mRNA, thus activating NF-κB signaling and promoting ovarian cancer metastasis and chemoresistance. Besides, TCGA data analysis suggested that TLR8-AS1 is elevated in ovarian cancer in comparison to adjacent non-cancerous tissues. High TLR8-AS1 expression levels were measured in metastatic ovarian cancer and correlated with poor patient prognosis. The clinical data supported the mechanism and biological significance of TLR8-AS1 dysregulation in ovarian cancer development. Our work demonstrates that TLR8-AS1 can be applied as a diagnostic and prognostic indicator for ovarian cancer, and maybe an alternative target for the treatment of ovarian cancer.

ASS1 regulates immune microenvironment via CXCL8 signaling in ovarian cancer

Ovarian cancer is one of the most serious and deadly cancers for female and currently no effective screening approaches have been achieved. Therefore it is usually diagnosed at an advanced stage and most patients have a poor prognosis. The development of ovarian cancer is a comprehensive process depending on the cross-talk between the various cells in the tumor microenvironment and the immune system. Thus, the immunotherapy may be revolutionized as an effective treatment of this disease. In this study, we firstly identified ASS1 as an immunomodulatory molecule. By RNA sequencing, antibody array and animal assys, we further provided new insights into understanding the crosstalk between ovarian cancer cells and their microenvironmental immune molecules , which may suggest a new potential therapeutic target for ovarian cancer.

β-TRCP-mediated AEBP2 ubiquitination and destruction controls cisplatin resistance in ovarian cancer

AEBP2 is a zinc finger protein and a potential targeting protein for the mammalian Polycomb Repression Complex 2 (PRC2). The role of AEBP2 in the regulation of the migration and development of the neural crest cells through the PRC2-mediated epigenetic mechanism has been well-documented. However, whether AEBP2 plays a role in cancer and how to regulate AEBP2 itself remains largely unknown. Here, we show that genetic knockout of AEBP2 inhibited ovarian cancer cells proliferation and increased cisplatin sensitivity. Moreover, AEBP2 contains a non-canonical phosphodegron and is constantly targeted for ubiquitylation and proteasomal degradation by a SKP1-CUL1-F-box protein (SCF) β-TrCP ubiquitin ligase complex. Failure to degrade AEBP2 conferred cisplatin resistance in ovarian cancer. Overall, this study reveals an oncogenic role of AEBP2 in ovarian cancer and provides a rationale to target β-TRCP-AEBP2 axis in ovarian cancer that may be therapeutically beneficial.

Hyperthermia synergistically enhances antitumor efficacy of PARP inhibitor through impacting homologous recombination repair and oxidative stress in vitro

Tumors with homologous recombination (HR) deficiency are particularly responsive to PARP inhibitors, however strategies to improve the sensitivity of epithelial ovarian carcinoma (EOC) with sufficient HR abilities still need to be deeply explored. In the present study, we firstly validated that hyperthermia (HT) changed diverse genes and signal pathways related to HR and oxidative stress in HR proficient EOC cells. HT impaired HR efficiency through inhibiting Olaparib (Olap) induced RAD51 foci formation in EOC cells, which was independent of the expression level of RAD51. Combination therapy of HT and Olap synergistically induced oxidative stress and oxidative DNA damage of EOC cells. Furthermore, we revealed that HT and Olap synergistically aggravated double-strand breaks of DNA in EOC cells. Conclusively, our findings confirmed that HT could synergistically enhance HR proficient EOC cells' sensitivity to PARP inhibitor through impairing HR efficiency and increasing oxidative stress.

Repurposing HIV protease inhibitors as senotherapeutic agents in cervical cancer: Dual targeting of CDK1/6-cell cycle arrest and p53/p21/p16 signaling axis

The clinical management of cervical cancer remains constrained by limited therapeutic options and a paucity of targeted pharmacological interventions. Drug repurposing emerges as a promising strategy to expedite oncological therapeutics development. This study systematically investigates the antineoplastic potential of HIV protease inhibitors saquinavir (SQV) and tipranavir (TPV) through multimodal mechanistic validation. In vitro analyses demonstrated dose-dependent inhibition of cervical cancer cell proliferation accompanied by significant upregulation of senescence-associated β-galactosidase (SA-β-Gal) activity. Molecular characterization revealed concomitant activation of senescence-regulatory proteins p53, p21, and p16, suggesting induction of tumor-suppressive senescence pathways. Transcriptomic profiling of inhibitor-treated SiHa cells identified critical cell cycle regulators CDK1 and CDK6, findings corroborated by molecular docking simulations revealing high-affinity binding to cyclin-dependent kinases (-32.0607 to -47.6820 kJ/mol). In vivo validation using xenograft models demonstrated comparable tumor growth inhibition to doxorubicin with preserved host viability and negligible systemic toxicity. Mechanistic integration revealed dual pathway modulation: G1-phase cell cycle arrest mediated through CDK1/6 suppression and coordinated activation of the p53/p21/p16 senescence signaling axis. These findings establish SQV and TPV as multi-targeted senotherapeutic agents, providing preclinical rationale for repurposing HIV antivirals as novel therapeutic strategy against cervical malignancies.

MS4A15 acts as an oncogene in ovarian cancer through reprogramming energy metabolism

Membrane-spanning 4-domains subfamily A 15 (MS4A15) belongs to transmembrane proteins and has been recognized as a regulator of various biological events including cell metabolism. Dysregulation of cell metabolism is a component of malignant transformation in numerous types of tumors, including ovarian cancer (OC). Nevertheless, whether MS4A15 is involved in OC progression remains obscure, as well as the underlying mechanisms. In the present study, we found that MS4A15 expression was significantly up-regulated in tumor tissues from OC patients compared with the matched normal adjacent samples. Higher MS4A15 expression predicted poorer overall survival rate in patients with OC. Our in vitro studies subsequently showed that MS4A15 knockdown markedly reduced the proliferation of OC cells, while its over-expression accelerated the proliferative capacity of OC cells through mediating the progression of G0/G1 cell cycle. Consistently, stable MS4A15 knockdown strongly inhibited the tumor growth in the established xenograft mouse models, along with evidently decreased expression of KI-67 positive staining. However, xenograft mouse models with MS4A15 over-expression exerted significantly accelerated tumor growth rates. We then found that MS4A15 reprogrammed energy metabolism to enhance OC progression. Under normal status, MS4A15 enhanced de novo lipid synthesis in OC cells. Upon glucose starvation, MS4A15 elevated oxidative phosphorylation (OXPHOS) to protect OC cells from starvation-induced cell death. Taken together, our findings demonstrated that MS4A15 may play an essential role in promoting OC growth mainly via reprogramming energy metabolism, and thus could be considered as a novel therapeutic target for OC treatment.

HN1 promotes tumor associated lymphangiogenesis and lymph node metastasis via NF-κB signaling activation in cervical carcinoma

Lymph node metastasis (LNM) is a critical cause for disease progression and treatment failure in cervical cancer. However, the mechanism underlying cervical cancer LNM remains unclear. In this study, HN1 was found to be dramatically upregulated in cervical cancer and patients with higher HN1 expression are more likely to exhibit a higher rate of LNM and lower survival rate. Univariate and multivariate Cox-regression analyses showed that HN1 is an independent prognostic factor in cervical cancer. Meanwhile, HN1 promotes lymphangiogenesis of cervical cancer in vitro. The in vivo experiment also indicates that HN1 enhances LNM in cervical cancer. Furthermore, we also found that HN1 activated the NF-κB signaling pathway to enhance the expression of downstream genes. Taken together, our study suggests that HN1 plays a crucial role in promoting LNM and acts as a prognostic biomarker in cervical cancer.

MIR31HG exhibits oncogenic property and acts as a sponge for miR-361-3p in cervical carcinoma

The long noncoding RNA (lncRNA) MIR31 Host Gene (MIR31HG) is a crucial regulator in malignant cancers. In this work, I examined the potential function and molecular mechanism of MIR31HG in cervical carcinoma progression. MIR31HG was strikingly upregulated in clinical cervical carcinoma specimens compared with that in adjacent samples. Functionally, knockdown of MIR31HG noticeably repressed cervical carcinoma cell growth and invasiveness in vitro and inhibited cervical carcinoma cell growth in vivo. Mechanistically, MIR31HG was identified as an endogenous 'sponge' through competing for miR-361-3p binding to modulate the miRNA target, epithelial membrane protein 1 (EMP1). Lastly, I verified that overexpression of EMP1 or miR-361-3p silencing effectively offset the impacts of MIR31HG knockdown on cervical carcinoma cell progression. In brief, these experimental results validate that MIR31HG is an oncogenic lncRNA that facilities cervical cancer progression.

UHRF1 silences gelsolin to inhibit cell death in early stage cervical cancer

Persistent infection with high-risk strains of human papillomavirus (HPV) is the primary cause of cervical cancer, the fourth most common cancer among women worldwide. Two oncoproteins encoded by the HPV genome, E6 and E7, are required for epigenetic modifications that promote cervical cancer development. We found that knockdown of HPV E6/E7 by siRNA reduced the levels of ubiquitin-like containing PHD and RING finger domain 1 (UHRF1) but increased the levels of gelsolin (GSN) in early stage cervical cancer cells. In addition, we found that UHRF1 levels were increased and GSN levels were decreased in early stage cervical cancer compared with those in normal cervical tissues, as shown by Western blot analysis, immunohistochemistry, and analysis of the Oncomine database. Moreover, knockdown of UHRF1 resulted in increased cell death in cervical cancer cell lines. Treatment of E6/E7-transformed HaCaT (HEK001) cells and HeLa cells with the DNA-hypomethylating agent 5-aza-2'-deoxycytidine and the histone deacetylase inhibitor Trichostatin A increased GSN expression levels. UHRF1 knockdown in HEK001 cells by siRNA or the UHRF1 antagonist thymoquinone increased GSN levels, induced cell cycle arrest and apoptosis, and increased the levels of p27 and cleaved PARP. Those results indicate that upregulation of UHRF1 by HPV E6/E7 causes GSN silencing and a reduction of cell death in early stage cervical cancer, suggesting that GSN might be a useful therapeutic target in early stage cervical cancer.

Engeletin suppresses cervical carcinogenesis in vitro and in vivo by reducing NF-κB-dependent signaling

Cervical cancer is an aggressive human cancer with poor prognosis among women, and urgently requires effective treatments. Engeletin (ENG, dihydrokaempferol 3-rhamnoside), as a flavanonol glycoside, could be found in various kinds of vegetables and fruits, exerting significant anti-inflammatory biological activities. However, its role in regulating cervical cancer, as well as the underlying molecular mechanisms are still unknown. In this study, we found that ENG treatments dose-dependently reduced the proliferation of cervical cancer cells. Epithelial to mesenchymal transition (EMT) process in cervical cancer was also restrained by ENG using transwell analysis, as evidenced by the significantly reduced migration and invasion. In addition, ENG treatments restricted vascular endothelial growth factor-A (VEGFA) expression in cervical cancer cells, contributing to the suppression of angiogenesis. Mechanistically, ENG significantly reduced the expression of chemokine (C-C motif) ligand 2 (CCL2) in cervical cancer cells associated with the blockage of nuclear factor-κB (NF-κB) signaling pathway. Moreover, ENG functioned as an inhibitor of NF-κB, which was involved in the repression of angiogenesis. In xenograft model, ENG treatment effectively reduced the tumor volume and weight, accompanied with decreased expression of phosphorylated NF-κB, CCL2 and VEGFA, and showed little influence on the body weight change. Therefore, ENG might be a potential therapeutic strategy for the treatment of cervical cancer.

NME4 modulates PD-L1 expression via the STAT3 signaling pathway in squamous cell carcinoma

NME4, also named Nm23-H4, is a contraction of NME/NM23 Nucleoside Diphosphate Kinase 4, whose major role is the synthesis of nucleoside triphosphates. However, its association with programmed death ligand 1 (PD-L1) remains far from understood. Herein, it was discovered that silencing NME4 can lead to the marked downregulation of PD-L1, with phosphorylated STAT3 at the 705th serine being inactivated in vitro in esophageal squamous cell carcinoma (ESCC) cell lines. To further validate the association between NME4 and PD-L1 that was observed in cell lines, Pearson correlation analysis was performed on the data regarding the transcriptomic RNA sequencing of NME4 and PD-L1 in cervical squamous cell carcinoma (CSCC), which pathologically highly resembles ESCC in terms of tumor origin, obtained from the GEPIA database. It was demonstrated that their correlation was significant but negative between NME4 and PD-L1 in CSCC. To the best of our knowledge, this is the first report describing a modulation exerted by NME4 over PD-L1 in the background of squamous cell carcinoma, strongly suggestive of the underlying role of NME4 working to exclude CD8 T cells from infiltrating into the squamous cell carcinoma microenvironment.

Dedifferentiation of neuroendocrine carcinoma of the uterine cervix in hypoxia

Neuroendocrine carcinoma of small cell type (SCNEC) is a rare pathological subtype in cervical cancer, which has a worse prognosis than other histological cell types. Due to its low incidence and the lack of experimental platforms, the molecular characteristics of SCNEC in the cervix remain largely unknown. Using the cancer tissue-originated spheroid (CTOS) method-an ex vivo 3D culture system that preserves the differentiation status of the original tumors-we established a panel of CTOS lines of SCNEC. We demonstrated that xenograft tumors and CTOSs, respectively, exhibited substantial intra-tumor and intra-CTOS variation in the expression levels of chromogranin A (CHGA), a neuroendocrine tumor marker. Since hypoxia affects differentiation in various tumors and in stem cells, we also investigated how hypoxia affected neuroendocrine differentiation of SCNEC of the uterine cervix. In the CTOS line cerv21, hypoxia suppressed expression of the neuroendocrine markers CHGA and synaptophysin (SYP). Flow cytometry analysis using CD99 (a membrane protein marker of SCNEC) revealed decreased CD99 expression in a subset of cells under hypoxic conditions. These expression changes were attenuated by HIF-1α knockdown, and by a Notch inhibitor, suggesting that these molecules played a role in the regulation of neuroendocrine differentiation. The examined SCNEC markers were suppressed under hypoxia in multiple CTOS lines. Overall, our present results indicated that neuroendocrine differentiation in SCNEC of the uterus is a variable phenotype, and that hypoxia may be one of the factors regulating the differentiation status.

Suppression of HIF-1α accumulation by betulinic acid through proteasome activation in hypoxic cervical cancer

Betulinic acid (BA) exhibits various biological activities such as anti-bacterial, anti-inflammatory, anti-human papilloma virus (HPV), and anti-cancer activities. HPV infection is associated with a high risk of cervical cancer, which is the leading cause of deaths among women worldwide. Therefore, BA is an attractive therapeutic agent for treating cervical cancer. In this study, we investigated the role of BA in regulating the hypoxia-mediated response in HeLa cells and clarified the underlying mechanism of action. We found that BA inhibited the hypoxia-induced accumulation of HIF-1α without affecting HIF-1α mRNA levels and suppressed the expression of HIF target genes, including VEGF, GLUT1, and PDK1 in HeLa cells. Additionally, BA enhanced the β1, β2, and β5 activities of the proteasome, which resulted in reduced levels of ubiquitinated proteins and HIF-1α protein in HeLa cells. However, BA treatment did not affect the deubiquitinase enzyme activity in HeLa cells. These results indicate that inhibition of HIF-1α accumulation by BA is mediated by activation of the proteasome, and BA is a potential anticancer agent for the regulation of the HIF signaling pathway.

MBNL1 regulates resistance of HeLa cells to cisplatin via Nrf2

Chemotherapy is an important method in the treatment of cervical cancer, but some patients will face drug resistance, which often indicates a poor prognosis. Moreover, there is no complete solution at present. Therefore, it is urgent to study the drug resistance mechanism of cervical cancer. Based on sequencing data mining, we predicted that MBNL1 might be involved in the occurrence and poor prognosis of cervical cancer, and verifed that MBNL1 could regulate the resistance of HeLa cells to cisplatin via Nrf2. In addition, we demonstrated that MBNL1 up regulated the degradation of Nrf2 protein by increasing the mRNA stability of Cul3. These results can provide theoretical basis for clinical development of new diagnosis and treatment targets for cisplatin resistance.

DGUOK-AS1 promotes cervical squamous cell carcinoma progression by suppressing miR-499a-5p that targets SPRR1B in vitro

Cervical squamous cell carcinoma (CESC) is the most common cancer type of cervical cancer, which threatens women's life seriously. LncRNA DGUOK-AS1has been reported to promote the biologic processes of CESC. We aim to figure out the role of DGUOK-AS1-miR-499a-5p-SPRR1B axis in modulating the CESC progression in vitro. The levels of DGUOK-AS1, miR-499a-5p, and SPRR1B in CESC tissues and cells were examined by RT-qPCR. The interaction of DGUOK-AS1-miR-499a-5p-SPRR1B was verified by luciferase assay. Inhibition of DGUOK-AS1, miR-499a-5p, and SPRR1B was applied for exploring the biological function based on detection of cell viability, proliferation, migration, and apoptosis in CESC SiHa and HeLa cells. DGUOK-AS1 and SPRR1B expressions were obviously elevated, whereas the expression of miR-499a-5p was reduced in both CESC tissues and cells. Silencing of DGUOK-AS1 attenuated cell growth and boosted apoptosis of CESC cells. Notably, DGUOK-AS1 inhibited miR-499a-5p to release SPRR1B, which significantly accelerated the development of CESC. DGUOK-AS1sponging miR-499a-5p facilitated CESC cells progression by releasing SPRR1B in vitro. It provides a new sight for the treatment of CESC patients involving DGUOK-AS1-miR-499a-5p-SPRR1B.

Oleic acid stimulates proliferation of RMG-1 ovarian cancer cells by activating the pentose phosphate pathway and glutamine metabolism

Extracellular fatty acids (FAs) play an important role in regulating cellular functions such as cell proliferation, survival, and migration. The effects of oleic acid (OA) on cancer cells vary depending on the cell type. Our prior study showed that two distinct ovarian cancer cell lines, RMG-1 and HNOA, proliferate in response to OA, but they differ with respect to glucose utilization. Here, we aimed to elucidate the mechanism(s) by which OA stimulates proliferation of RMG-1 cells. We found that OA stimulates RMG-1 proliferation by activating the FA transporter CD36. OA also increases uptake of glucose and glutamine, which subsequently activate the pentose phosphate pathway (PPP) and glutamine metabolism, respectively. Given that ribose 5-phosphate derived from the PPP is utilized for glutamine metabolism and the subsequent de novo nucleotide synthesis, our findings suggest that OA affects the PPP associated with Gln metabolism, rather than glycolysis associated with glutaminolysis; this leads ultimately to activation of DNA synthesis, which is required for cell proliferation. This selective activation by OA contrasts with the mechanisms observed in HNOA cells, in which OA-induced cell proliferation is driven by transcriptional regulation of the GLUT gene. The diverse responses of cancer cells to OA may be attributed to distinct mechanisms of OA reception and/or different metabolic pathways activated by OA.

Bufalin: A promising therapeutic drug against the cisplatin-resistance of ovarian cancer by targeting the USP36/c-Myc axis

Cisplatin (DPP) resistance is a severe obstacle to ovarian cancer (OC) treatment. Our research aims to uncover the therapeutic effect and the underlying mechanism of Bufalin against DDP resistance. The cell viability, proliferation capacity, γH2AX expression, and apoptosis ratio were quantified via CCK8 assay, colony formation assay, immunofluorescence, and flow cytometry analysis respectively. Xenografting experiment was performed to detect the tumor growth. Molecular docking was applied to mimic the combination of Bufalin and USP36 protein, and Western blotting was conducted to measure the Bax, Bcl-2, γH2AX, USP36, and c-Myc expression. The c-Myc ubiquitination and half-life were detected via ubiquitination assay and cycloheximide chasing assay. Bufalin treatment notably suppressed the cell viability and colony numbers, and increased the apoptosis ratio and γH2AX level in the DDP treatment group. Bufalin therapy also notably inhibited tumor growth, Bax, Bcl-2, and γH2AX expression in vivo. Moreover, the Bufalin application remarkedly reduced the c-Myc expression and half-life and increased the c-Myc ubiquitination via interaction and subsequent down-regulation of USP36. Knockdown of USP36 reversed the antiproliferative effect and proapoptotic capacity of Bufalin therapy in the DDP treatment group. In conclusion, Bufalin can overcome the DDP resistance in vitro and in vivo via the USP36/c-Myc axis, which innovatively suggests the therapeutic potential of Bufalin against DDP resistance ovarian cancer.

A linear five-ring pyrrole-imidazole polyamide-triphenylphosphonium conjugate targeting a mitochondrial DNA mutation efficiently induces apoptosis of HeLa cybrid cells carrying the mutation

Somatic mutations in mitochondrial DNA may provide a new avenue for cancer therapy due to their associations to a number of cancers and a tendency of homoplasmicity. In consideration of mitochondrial features and its relatively small genome size, a nucleotide-based targeting approach is a considerably more promising option. To explore the efficacy of short linear N-methylpyrrole-N-methylimidazole polyamide (PI polyamide), we synthesized a five-ring short PI polyamide that provided sequence-specific homing for the A3243G mitochondrial mutation upon conjugation with triphenylphosphonium cation (TPP). This PI polyamide-TPP was able to induce cytotoxicity in HeLamtA3243G cybrid cells, while preserving preferential binding for oligonucleotides containing the A3243G motif from melting temperature assays. The PI polyamide-TPP also localized in the mitochondria in HeLamtA3243G cells and induced mitochondrial reactive oxygen species production, mitophagy and apoptosis in a mutation-specific fashion compared to the wild-type HeLamtHeLa cybrids; normal human dermal fibroblasts were also relatively unaffected to suggest discriminating selectivity for the mutant mitochondria, offering a novel outlook for cancer therapy via mitochondrial homing of short linear PIP-TPPs.

Hypoxic induction of apoptosis occurs through HIF-1α and accompanies mammalian sterile 20-like kinase 2 cleavage in human endometrial adenocarcinoma Ishikawa cells

The incidence of endometrial cancer is increasing worldwide. One of the main causes of this cancer is a hormone imbalance; progesterone derivatives have been used for treatment. However, reports have shown that hypoxia plays important and possibly beneficial roles in endometrial function. Here, we show the effect of hypoxia on the proliferation of human endometrial adenocarcinoma Ishikawa cells. Hypoxia induced caspase-dependent apoptosis in Ishikawa cells. Overexpression and siRNA-mediated knockdown of hypoxia-inducible factor-1α (HIF-1α) confirmed that HIF-1α accelerates hypoxia-induced cell death. Treatment with dimethyloxalglycine, which stabilizes HIF-1α, suppressed cell proliferation. Kaplan-Meier analysis showed that the expression level of HIF-1α has a significant positive effect on the survival rate of endometrial cancer patients. In our search for cellular targets involved in hypoxic apoptosis, we noticed that mammalian sterile 20-like kinase 2 (MST2), a member of the Hippo pathway, was positively correlated with HIF-1α expression in 176 endometrial cancer patients extracted from the TCGA database. Hypoxia induced caspase-dependent MST2 cleavage. In addition, a MST2 inhibitor suppressed HIF-1α-mediated reporter activity. These results suggest HIF-1α and the Hippo signaling pathway are involved in endometrial cancer.

Histone arginine methyltransferase CARM1 selective inhibitor TP-064 induces apoptosis in endometrial cancer

Histone modification is the key epigenetic mechanism that regulates gene expression. Coactivator-associated arginine methyltransferase 1 (CARM1) is an arginine methyltransferase that catalyzes dimethylation of histone H3 (H3R17) at arginine 17. Lately, it has been suggested that CARM1 is associated with human carcinogenesis, and the CARM1-selective inhibitor, TP-064, has been shown to be a potential therapeutic agent for multiple myeloma. However, the physiological significance of CARM1 in endometrial cancer remains unclear. Therefore, we aimed to explore the role of CARM1 and the effect of TP-064 in endometrial cancer. To this end, we analyzed CARM1 expression in endometrial cancer using quantitative real-time polymerase chain reaction and examined the antitumor mechanism with CARM1 knockdown endometrial cancer cells. Moreover, we evaluated the therapeutic capability of TP-064 in endometrial cancer cells. CARM1 was remarkably overexpressed in 52 endometrial cancer tissues compared to normal endometrial tissues. The growth of CARM1 knockdown endometrial cancer cells was suppressed and CARM1 knockdown induced apoptosis. TP-064 also inhibited endometrial cancer cell growth and declined the number of endometrial cancer cell colonies. These data suggest that CARM1 may be a powerful therapeutic target for endometrial cancer.