Journal

Cancer Letters

Papers (84)

Formation of polyploid giant cancer cells and the transformative role of human cytomegalovirus IE1 protein

Human cytomegalovirus (HCMV) infection has been linked to various cancers, including glioblastoma (GB), breast cancer (BC), and ovarian epithelial cancer (OC) especially high grade serous ovarian cancer (HGSOC). HCMV gene products control tumorigenic cellular pathways and processes associated with all the hallmarks of cancer. Among the suspected HCMV proteins involved in cellular transformation, the immediate early-1 (IE1) protein stands out as a significant player. Herein, we presented the experimental evidence supporting HCMV-IE1 role as a reprogramming factor that induces the transformation of human ovarian epithelial cells (OECs) resulting in the generation of "CMV transformed ovarian epithelial cells-IE1″ or CTO-IE1. These transformed cells exhibit similarities to those previously reported by our group, following infection with the high-risk oncogenic HCMV strain DB. HCMV-IE1-DB protein triggered distinct cellular and molecular mechanisms in stably transduced OECs. This included downregulation of Rb/p53 and upregulation of Myc/EZH2, concurrent with the emergence of polyploid giant cancer cells (PGCCs) and giant cell cycling in the culture. HCMV-IE1-DB silencing limited cellular transformation and stemness. In HGSOC, PGCCs were detected in the presence of IE1; the latter positively correlated with Myc. In addition, HCMV IE1 exhibits transforming capabilities in human mammary epithelial cells (HMECs) and human astrocytes (HAs) in vitro, reflecting its potential role in the transformation observed in vivo. This highlights the tumorigenic properties of Myc/EZH2 in the context of IE1-mediated transformation parallel to PGCCs appearance.

Blockade of the lncRNA-PART1-PHB2 axis confers resistance to PARP inhibitor and promotes cellular senescence in ovarian cancer

PARPi is currently the most important breakthrough in the treatment of ovarian cancer in decades, and it has been integrated into the initial maintenance therapy for ovarian cancer. However, the mechanism leading to PARPi resistance remains unelucidated. Our study aims to screen novel targets to better predict and reverse resistance to PARPi and explore the potential mechanism. Here, we conducted a comparative analysis of differentially expressed genes between platinum-sensitive and platinum-resistant groups within the TCGA ovarian cancer cohort. The analysis indicated that lncRNA PART1 was significantly highly expressed in platinum-sensitive patients compared to platinum-resistant individuals in TCGA-OV cohort and further validated in the GEO dataset and Qilu hospital cohort. Moreover, the upregulation of PART1 was positively correlated with a favorable prognosis in ovarian cancer. Furthermore, in vitro and in vivo experiments showed that inhibition of PART1 conferred resistance to both cisplatin and PARP inhibitor and promoted cellular senescence. Senescent cells are more resistant to chemotherapeutics. RNA antisense purification and RNA immunoprecipitation assays revealed an interaction between PART1 and PHB2, a crucial mitophagy receptor. Knockdown of PART1 could promote the degradation of PHB2, impairing mitophagy and leading to cellular senescence. Rescue assays indicated that overexpression of PHB2 remarkably diminished the resistance to PARPi and cellular senescence caused by PART1 knockdown. PDX models were utilized to further confirm the findings. Altogether, our study demonstrated that lncRNA PART1 has the potential to serve as a novel promising target to reverse resistance to PARPi and improve prognosis in ovarian cancer.

The feedback loop of AURKA/DDX5/TMEM147-AS1/let-7 drives lipophagy to induce cisplatin resistance in epithelial ovarian cancer

Platinum-taxane chemotherapy is the first-line standard-of-care treatment administered to patients with epithelial ovarian cancer (EOC), and faces the major challenge of cisplatin resistance. Aurora Kinase A (AURKA) is a serine/threonine kinase, acting as an oncogene by participating in microtubule formation and stabilization. In this study, we demonstrate that AURKA binds with DDX5 directly to form a transcriptional coactivator complex to induce the transcription and upregulation of an oncogenic long non-coding RNA, TMEM147-AS1, which sponges hsa-let-7b/7c-5p leading to the increasing expression of AURKA as a feedback loop. The feedback loop maintains EOC cisplatin resistance via activation of lipophagy. These findings underscore the feedback loop of AURKA/DDX5/TMEM147-AS1/let-7 provides mechanistic insights into the combined use of TMEM147-AS1 siRNA and VX-680, which can help improve EOC cisplatin treatment. Our mathematical model shows that the feedback loop has the potential to act as a biological switch to maintain on- (activated) or off- (deactivated) status, implying the possible resistance of single use of VX-680 or TMEM147-AS1 siRNA. The combined use reduces both the protein level of AURKA using TMEM147-AS1 siRNA and its kinase activity using VX-680, showing more significant effect than the use of TMEM147-AS1 siRNA or VX-680 alone, which provides a potential strategy for EOC treatment.

Predictors of para-aortic lymph node metastasis based on pathological diagnosis via surgical staging in patients with locally advanced cervical cancer: A multicenter study

Para-aortic lymph node (PALN) metastasis of patients with locally advanced cervical cancer (LACC) is associated with multiple risk factors. This study aimed to identify risk factors and develop a predictive model for PALN metastasis based on the pathological diagnosis via surgical staging to determine the patient-population suitable for extended-field irradiation (EFRT) and clarify the prognosis of patients with LACC. Five parameters were identified as predictors by logistic regression analysis. The predictive model was displayed as a nomogram and then modified into a simple scoring system. The concordance indices for the prediction nomogram were 0.939 in the training cohort, and 0.954 in the validation cohort, respectively. The scoring system consisted of tumor size, histological type, number of pelvic lymph nodes (PLNs), common iliac lymph node, and shorter diameter of the largest PLN. With a cutoff value of 8 points, the sensitivity and specificity of the predictive model were 91.04 % and 85.37 %, respectively, in the training cohort, and 89.47 % and 84.68 %, respectively, in the validation cohort. Using this system, patients were divided into high- and low-risk groups. Patients in the high-risk group showed a greater likelihood of PALN metastasis and worse PFS and OS than those in the low-risk group. The predictive model displays promise for the pathological diagnosis of PALN via surgical staging, offering good accuracy. It provides a non-invasive, practical tool to guide precise radiation strategy and stratify prognosis of patients with LACC.

A previously uncharacterized role of TAp73 in ferroptosis by modulating oxidative homeostasis in cervical cancer

While the tumor-suppressive functions of p53 are well established, the role of its homolog, TAp73, in cancer remains incompletely characterized and is a subject of active investigation. In this study, we observed downregulation of TAp73 protein expression in cervical cancer tissues, which significantly correlated with adverse clinical outcomes. Through co-expression network analysis, we identified functional associations between TAp73 and key pathways involved in lipid metabolism and redox homeostasis-both critical regulators of ferroptosis, an iron-dependent form of programmed cell death mediated by lipid peroxidation. Mechanistically, we demonstrate that TAp73 promotes ferroptosis by directly upregulating the transcription of β-transducin repeat-containing protein (β-TRCP), thereby facilitating the ubiquitin-dependent degradation of nuclear factor erythroid 2-related factor 2 (NRF2), a master regulator of cellular antioxidant defenses. This TAp73-mediated suppression of NRF2 activity renders cells more susceptible to ferroptotic death. Furthermore, TAp73 expression is transcriptionally induced during ferroptosis through the combined inactivation of enhancer of zeste homolog 2 (EZH2), a core component of polycomb repressive complex 2, and activation of E2F transcription factor 1 (E2F1). Notably, pharmacological inhibition of EZH2 synergized with sulfasalazine (SAS) to enhance ferroptosis in vivo, an effect largely dependent on TAp73. Together, these findings delineate a novel ferroptosis regulatory axis-EZH2/TAp73/β-TRCP/NRF2-and highlight its potential as a therapeutic target for cervical cancer intervention.

ZNF251 haploinsufficiency confers PARP inhibitors resistance in BRCA1-mutated cancer cells through activation of homologous recombination

Poly (ADP-ribose) polymerase inhibitors (PARPis) represent a promising new class of agents that have demonstrated efficacy in treating various cancers, particularly those with BRCA1/2 mutations. Cancer-associated BRCA1/2 mutations disrupt DNA double-strand break (DSB) repair via homologous recombination (HR). PARP inhibitors (PARPis) have been used to trigger synthetic lethality in BRCA1/2-mutated cancer cells by promoting the accumulation of toxic DSBs. Unfortunately, resistance to PARPis is common and can occur through multiple mechanisms, including the restoration of HR and/or stabilization of replication forks. To gain a better understanding of the mechanisms underlying PARPis resistance, we conducted an unbiased CRISPR-pooled genome-wide library screen to identify new genes whose deficiency confers resistance to the PARPi olaparib. Our research revealed that haploinsufficiency of the ZNF251 gene, which encodes zinc finger protein 251, is associated with resistance to PARPis in various breast and ovarian cancer cell lines carrying BRCA1 mutations. Mechanistically, we discovered that ZNF251 haploinsufficiency leads to stimulation of RAD51-mediated HR repair of DSBs in olaparib-treated BRCA1-mutated cancer cells. Moreover, we demonstrated that a RAD51 inhibitor reversed PARPi resistance in ZNF251 haploinsufficient cancer cells harboring BRCA1 mutations. Our findings provide important insights into the mechanisms underlying PARPis resistance by highlighting the role of RAD51 in this phenomenon.

S100A7 orchestrates neutrophil chemotaxis and drives neutrophil extracellular traps (NETs) formation to facilitate lymph node metastasis in cervical cancer patients

Neutrophil extracellular traps (NETs) have been shown to promote the metastatic potential of many kinds of tumors. Our study aimed to investigate the role and mechanisms of NETs in lymph node metastasis (LNM) of cervical cancer (CCa), and evaluated the therapeutic value of targeting NETs in CCa. Immunohistochemistry demonstrated that neutrophil infiltration and NETs formation were increased in CCa patients with LNM, as well as confirming a positive correlation between S100A7 expression and neutrophil infiltration in CCa. NETs enhanced the migratory capability of CCa by activating the P38-MAPK/ERK/NFκB pathway through interaction with TLR2. Digesting NETs with deoxyribonuclease 1 (DNase 1) or inhibiting TLR2 with chloroquine eliminated the NETs-induced metastatic potential of CCa. Additionally, NETs promoted lymphangiogenesis and increased the permeability of lymphatic vessels, thus facilitating translymphatic movement of CCa. CCa-derived S100A7 exhibited a chemotactic effect on neutrophils and promoted NETs generation by elevating ROS levels rather than activating autophagy in neutrophils. The mouse model with footpad implantation illustrated that DNase 1 effectively reduced LNM in LPS-induced mice and in mice seeded with S100A7-overexpressing CCa cells. In conclusion, our study reveals a new tumor-promoting mechanism of S100A7, clarifies the crucial role and mechanism of NETs in LNM of CCa, and indicates that the NETs-targeted therapy emerges as a promising anti-metastasis therapy in CCa.

Targeting doublecortin-like kinase 1 reveals a novel strategy to circumvent chemoresistance and metastasis in ovarian cancer

Ovarian cancer (OvCa) has a dismal prognosis because of its late-stage diagnosis and the emergence of chemoresistance. Doublecortin-like kinase 1 (DCLK1) is a serine/threonine kinase known to regulate cancer cell "stemness", epithelial-mesenchymal transition (EMT), and drug resistance. Here we show that DCLK1 is a druggable target that promotes chemoresistance and tumor progression of high-grade serous OvCa (HGSOC). Importantly, high DCLK1 expression significantly correlates with poor overall and progression-free survival in OvCa patients treated with platinum chemotherapy. DCLK1 expression was elevated in a subset of HGSOC cell lines in adherent (2D) and spheroid (3D) cultures, and the expression was further increased in cisplatin-resistant (CPR) spheroids relative to their sensitive controls. Using cisplatin-sensitive and resistant isogenic cell lines, pharmacologic inhibition (DCLK1-IN-1), and genetic manipulation, we demonstrate that DCLK1 inhibition was effective at re-sensitizing cells to cisplatin, reducing cell proliferation, migration, and invasion. Using kinase domain mutants, we demonstrate that DCLK1 kinase activity is critical for mediating CPR. The combination of cisplatin and DCLK1-IN-1 showed a synergistic cytotoxic effect against OvCa cells in 3D conditions. Targeted gene expression profiling revealed that DCLK1 inhibition in CPR OvCa spheroids significantly reduced TGFβ signaling, and EMT. We show in vivo efficacy of combined DCLK1 inhibition and cisplatin in significantly reducing tumor metastases. Our study shows that DCLK1 is a relevant target in OvCa and combined targeting of DCLK1 in combination with existing chemotherapy could be a novel therapeutic approach to overcome resistance and prevent OvCa recurrence.

Pharmacological inhibition of KDM1A/LSD1 enhances estrogen receptor beta-mediated tumor suppression in ovarian cancer

Ovarian cancer (OCa) is the most lethal gynecologic cancer. Emerging data indicates that estrogen receptor beta (ERβ) functions as a tumor suppressor in OCa. Lysine-specific histone demethylase 1A (KDM1A) is an epigenetic modifier that acts as a coregulator for steroid hormone receptors. However, it remain unknown if KDM1A interacts with ERβ and regulates its expression/functions in OCa. Analysis of TCGA data sets indicated KDM1A and ERβ expression showed an inverse relationship in OCa. Knockout (KO), knockdown (KD), or inhibition of KDM1A increased ERβ isoform 1 expression in established and patient-derived OCa cells. Further, KDM1A interacts with and functions as a corepressor of ERβ, and its inhibition enhances ERβ target gene expression via alterations of histone methylation marks at their promoters. Importantly, KDM1A-KO or -KD enhanced the efficacy of ERβ agonist LY500307, and the combination of KDM1A inhibitor (KDM1Ai) NCD38 with ERβ agonist synergistically reduced the cell viability, colony formation, and invasion of OCa cells. RNA-seq and DIA mass spectrometry analyses showed that KDM1A-KO resulted in enhanced ERβ signaling and that genes altered by KDM1A-KO and ERβ agonist were related to apoptosis, cell cycle, and EMT. Moreover, combination treatment significantly reduced the tumor growth in OCa orthotopic, syngeneic, and patient-derived xenograft models and proliferation in patient-derived explant models. Our results demonstrate that KDM1A regulates ERβ expression/functions, and its inhibition improves ERβ mediated tumor suppression. Overall, our findings suggest that KDM1Ai and ERβ agonist combination therapy is a promising strategy for OCa.

METTL3-mediated N6-methyladenosine modification and HDAC5/YY1 promote IFFO1 downregulation in tumor development and chemo-resistance

Ovarian cancer (OC) is a malignant tumor that seriously threatens women's health. Due to the difficulty of early diagnosis, most patients exhibit advanced disease or peritoneal metastasis at diagnosis. We discovered that IFFO1 is a novel tumor suppressor, but its role in tumorigenesis, development and chemoresistance is unknown. In this study, IFFO1 levels were downregulated across cancers, leading to the acceleration of tumor development, metastasis and/or cisplatin resistance. Overexpression of IFFO1 inhibited the translocation of β-catenin to the nucleus and decreased tumor metastasis and cisplatin resistance. Furthermore, we demonstrated that IFFO1 was regulated at both the transcriptional and posttranscriptional levels. At the transcriptional level, the recruitment of HDAC5 inhibited IFFO1 expression, which is mediated by the transcription factor YY1, and the METTL3/YTHDF2 axis regulated the mRNA stability of IFFO1 in an m6A-dependent manner. Mice injected with IFFO1-overexpressing cells had lower ascites volumes and tumor weights throughout the peritoneal cavity than those injected with parental cells expressing the vector control. In conclusion, we demonstrated that IFFO1 is a novel tumor suppressor that inhibits tumor metastasis and reverses drug resistance in ovarian cancer. IFFO1 was downregulated at both the transcriptional level and posttranscriptional level by histone deacetylase and RNA methylation, respectively, and the IFFO1 signaling pathway was identified as a potential therapeutic target for cancer.

Integrated analysis of ascites and plasma extracellular vesicles identifies a miRNA-based diagnostic signature in ovarian cancer

Ovarian cancer is mostly diagnosed at advantaged stages due to the lack of early diagnostic biomarkers. The common metastasis pattern is characterized by peritoneal dissemination with a formation of malignant ascites. Extracellular vesicles (EVs) are emerging as promising clinical biomarkers in liquid biopsy. Here, we aimed to investigate robust liquid biopsy-based EV miRNA biomarkers for ovarian cancer diagnosis and metastasis regulation. EVs were isolated from malignant ascites and plasma of ovarian cancer patients as well as the benign control counterparts of patients with benign gynecologic diseases. EV small RNA sequencing identified a panel of eight miRNAs (miR-1246, miR-1290, miR-483, miR-429, miR-34b-3p, miR-34c-5p, miR-145-5p, miR-449a) based on dysregulated miRNAs overlapped in the ascites and plasma subset. The ovarian cancer EV miRNA (OCEM) signature developed based on these eight miRNAs demonstrated high diagnostic accuracy in our in-house dataset and multiple public datasets across diverse clinical samples (blood, tissue and urine). In addition, malignant ascites-derived EVs could significantly facilitate the aggressive property of ovarian cancer cells and boost the growth of ascites-derived organoids. Notably, miR-1246 and miR-1290 shuttled in malignant ascites-derived EVs were identified to promote the invasion and migration of ovarian cancer cells through regulating a common target RORα.

Targeted delivery of exosomal miR-484 reprograms tumor vasculature for chemotherapy sensitization

The vascular dysfunction of ovarian cancer (OC) contributes to the chemotherapeutic resistance. In this study, we aimed to explore whether exosome-mediated angiogenesis blocking could improve the chemotherapy sensitivity via vascular normalization. Exosomes were armed with RGD on the surface by fusing Lamp2b. Candidate miRNAs related to tumor angiogenesis was detected by qRT-PCR. RGD-modified exosomes were loaded with miRNAs via electroporation. The therapeutic effects of the exosomes on angiogenesis, vascular normalization, and chemotherapy sensitivity were systemically analyzed in the xenograft model. RGD-modified exosomes were relatively enriched in the tumor mass, both the tumor cell and the endothelial cells. Among the miRNA candidates, miR-484 was found down-regulated in both the cancer cells and the angiogenic endothelial cells. In vivo xenograft model experiment revealed that injection of RGD-modified exosomes loaded with miR-484 induced vessel normalization and in turn sensitized the cancer cells to chemotherapy induced apoptosis. Mechanistically, miR-484 simultaneously inhibited the expression of VEGF-A from the cancer cells and the corresponding receptors in the endothelial cells. Targeted delivery of miR-484 via RGD-modified exosomes improves the vascular normalization, sensitizes the cancer to chemotherapy, and prolongs the survival time of tumor-bearing mice after chemotherapy, opening an avenue for the clinical management of chemotherapy resistance.

ARID1A-dependent permissive chromatin accessibility licenses estrogen-receptor signaling to regulate circadian rhythms genes in endometrial cancer

Estrogen receptor α (ER) acts as an oncogenic signal in endometrial endometrioid carcinoma. ER binding activity largely depends on chromatin remodeling and recruitment of transcription factors to estrogen response elements. A deeper understanding of these regulatory mechanisms may uncover therapeutic targets for ER-dependent endometrial cancers. We show that estrogen induces accessible chromatin and ER binding at a subset of enhancers, which form higher-order super enhancers that are vital for ER signaling. ER positively correlates with active enhancers in primary tumors, and tumors were effectively classified into molecular subtypes with chromatin accessibility dynamics and ER-dependent gene signature. ARID1A binds within ER-bound enhancers and regulates ER-dependent transcription. Knockdown of ARID1A or fulvestrant treatment profoundly affects the gene-expression program, and inhibits cell growth phenotype by affecting the chromatin environment. Importantly, we found dysregulated expression of circadian rhythms genes by estrogen in cancer cells and in primary tumors. Knockdown of ARID1A reduces the chromatin accessibility and ER binding at enhancers of the circadian gene ARNTL and BHLHE41, leading to a decreased expression of these genes. Altogether, we uncover a critical role for ARID1A in ER signaling and therapeutic target in ER-positive endometrial cancer.

A Pt (IV)/losartan/immunotherapy Co-delivery thermosensitive gel synergizes STING activation and cancer-associated fibroblast inhibition for ovarian cancer chemoimmunotherapy

Currently, intraperitoneal (IP) chemoimmunotherapy offers synergistic effect, pharmacokinetic advantages and reduced systemic toxicity, achieving significant progress in peritoneal metastatic ovarian cancer (OC). However, its efficacy is limited by poor drug retention, lack of targeting, inadequate tumor penetration, drug resistance, and immunosuppression tumor microenvironment (TME). To address these challenges, a "three-in-one" thermosensitive gel system (PM/LOS@FLP/P1@G) was developed. Here, platinum prodrug (Pt-2CLB), TME modulator losartan (LOS), and immune checkpoint inhibitor (ICI) anti-PD-1 (P1) are integrated into a hierarchical micelle-liposome-thermosensitive gel structure, resulting in enhanced chemo-immunotherapy. Specifically, the enhancement of antitumor efficacy primarily involves five mechanisms: (i) prolonged IP retention and tumor tissue contact-dependent active targeting mediated by thermosensitive gel and folate-targeting; (ii) matrix metalloproteinase (MMP) and reduced glutathione (GSH)-triggered spatiotemporally sequential delivery of LOS to cancer-associated fibroblasts (CAFs), Pt-2CLB to tumor cells, and P1 to the PD-1/PD-L1 axis; (iii) the DNA damage, GSH depletion, and ROS accumulation induced by Pt-2CLB not only amplify chemotherapeutic efficacy while suppressing drug resistance but also activate the cGAS-STING signaling pathway, thereby enhancing immune responses; (iv) the blockade of transforming growth factor-β (TGF-β)/Smad signaling pathway by LOS inhibits CAFs activation and tumor extracellular matrix (ECM) production, thereby promoting the penetration of drugs and immune cells, boosting chemoimmunotherapy; (v) chemoimmunotherapy synergy exerts potent antitumor effects. In summary, PM/LOS@FLP/P1@G exhibited excellent antitumor efficacy and safety, demonstrating a significant tumor inhibition rate (93.28 %) and survival extension, while fostering immune memory to prevent recurrence, representing a promising IP chemoimmunotherapy strategy for peritoneal metastatic OC.

Autophagy is essential for survival and function of polyploid giant cancer cells under therapeutic stress

Polyploid giant cancer cells (PGCCs) are enlarged, multinucleated tumor cells that arise in response to stressors such as chemotherapy and are increasingly recognized as key drivers of recurrence and metastasis in aggressive cancers. Found in triple-negative breast cancer (TNBC) and ovarian cancer (OC), PGCCs can survive cytotoxic therapy in a dormant state and later produce chemoresistant progeny through amitotic budding. Here, we investigated the role of autophagy in paclitaxel (PTX)-induced PGCC survival, nuclear maintenance, and migration. PGCCs generated from MDA-MB-231 and HEY cells were significantly larger, more heterogeneous, and more resistant to PTX than parent cells. Transcriptomic profiling revealed enrichment of metabolic and cytoskeletal pathways, with strong upregulation of autophagy-related genes, including SQSTM1 (P62), LC3, and LAMP1. PGCCs exhibited elevated oxidative stress and marked induction of mitochondrial superoxide dismutase 2 (SOD2). p62 was localized near micronuclei, and prolonged autophagy inhibition with Bafilomycin A1 reduced nuclear size, heterogeneity, and micronuclei number. PGCCs also displayed a dispersed vimentin intermediate filament network that scaffolded autophagic structures; autophagy inhibition impaired migration in PGCC-derived daughter cells. These findings identify autophagy as a critical process sustaining PGCC survival, structural integrity, and motility, and suggest that targeting autophagy may disrupt PGCC-driven recurrence in aggressive cancers.

Identification of the MRTFA/SRF pathway as a critical regulator of quiescence and chemotherapy resistance in cancer

Chemoresistance is a major cause of cancer deaths. One understudied mechanism of chemoresistance is quiescence. We used single-cell culture to identify and isolate patient-derived proliferating and quiescent ovarian cancer cells (qOvCa). RNA-seq analysis indicated that hundreds of genes that are differentially expressed in qOvCa cells are transcriptional targets of the Myocardin-Related Transcription Factor-A/Serum Response Factor (MRTFA/SRF) pathway, and both genetic disruption and pharmacologic inhibition of MRTFA/SRF interaction (with the inhibitor CCG257081) induced quiescence across multiple cancer types. MRTFA/SRF inhibition-mediated quiescence is p27/Kip1 dependent and associated with a downregulation of cell cycle regulators, NCL, MYH9, and alterations in the proteasome. We show that the MRTFA/SRF axis plays a dual role in chemotherapy resistance, with both pathway inhibition and activation contributing to chemotherapy resistance in vitro and in patient samples. CCG081 treatment results in a proteasome-dependent downregulation of the stem-cell marker CD133. Suggesting a critical role for the proteasome in quiescent cells, CCG081 therapy sensitized OvCa cells to proteasome inhibitors. In vivo, we found that CCG257081 therapy could be used to induce tumor growth-arrest and delay disease growth to improve overall survival. Moreover, we found that dual therapy with CCG081 and proteasome inhibition further improved outcomes, leading to undetectable tumors in ∼20% of mice. Together, these data suggest that the MRTFA/SRF pathway is a critical regulator of quiescence in cancer and a potential therapeutic target.

Versican secreted by the ovary links ovulation and migration in fallopian tube derived serous cancer

High grade serous ovarian cancers (HGSOC) predominantly arise in the fallopian tube epithelium (FTE) and colonize the ovary first, before further metastasis to the peritoneum. Ovarian cancer risk is directly related to the number of ovulations, suggesting that the ovary may secrete specific factors that act as chemoattractants for fallopian tube derived tumor cells during ovulation. We found that 3D ovarian organ culture produced a secreted factor that enhanced the migration of FTE non-tumorigenic cells as well as cells harboring specific pathway modifications commonly found in high grade serous cancers. Through size fractionation and a small molecule inhibitors screen, the secreted protein was determined to be 50-100kDa in size and acted through the Epidermal Growth Factor Receptor (EGFR). To correlate the candidates with ovulation, the PREDICT organ-on-chip system was optimized to support ovulation in a perfused microfluidic platform. Versican was found in the correct molecular weight range, contained EGF-like domains, and correlated with ovulation in the PREDICT system. Exogenous versican increased migration, invasion, and enhanced adhesion of both murine and human FTE cells to the ovary in an EGFR-dependent manner. The identification of a protein secreted during ovulation that impacts the ability of FTE cells to colonize the ovary provides new insights into the development of strategies for limiting primary ovarian metastasis.

Three-dimensional chromatin analysis reveals Sp1 as a mediator to program and reprogram HPV-host epigenetic architecture in cervical cancer

Human papillomavirus (HPV) is predominantly associated with HPV-related cancers, however, the precise mechanisms underlying the HPV-host epigenetic architectures in HPV carcinogenesis remain elusive. Here, we employed high-throughput chromosome conformation capture (Hi-C) to comprehensively map HPV16/18-host chromatin interactions. Our study identified the transcription factor Sp1 as a pivotal mediator in programming HPV-host interactions. By targeting Sp1, the active histone modifications (H3K27ac, H3K4me1, and H3K4me3) and the HPV-host chromatin interactions are reprogrammed, which leads to the downregulation of oncogenes located near the integration sites in both HPV (E6/E7) and the host genome (KLF5/MYC). Additionally, Sp1 inhibition led to the upregulation of immune checkpoint genes by reprogramming histone modifications in host cells. Notably, humanized patient-derived xenograft (PDX-HuHSC-NSG) models demonstrated that Sp1 inhibition promoted anti-PD-1 immunotherapy via remodeling the tumor immune microenvironment in cervical cancer. Moreover, single-cell transcriptomic analysis validated the enrichment of transcription factor Sp1 in epithelial cells of cervical cancer. In summary, our findings elucidate Sp1 as a key mediator involved in the programming and reprogramming of HPV-host epigenetic architecture. Inhibiting Sp1 with plicamycin may represent a promising therapeutic option for HPV-related carcinoma.

SMARCA4 and SMARCA2 co-deficiency: An uncommon molecular signature defining a subset of rare, aggressive and undifferentiated malignancies associated with defective chromatin remodeling

Genetic mutations and epigenetic modifications affecting multiple cancer-related genes occur synergistically to drive tumorigenesis. Across a wide spectrum of cancers, pathogenic changes have been identified in members of the SWItch/Sucrose Non-Fermentable complex including its two catalytic subunits, SMARCA4 and SMARCA2. During cancer development, it is not uncommon to lose the function of either SMARCA4 or SMARCA2, however, loss of both together has been reported to be synthetic lethal and therefore unexpected. Co-deficiency of SMARCA4 and SMARCA2 occurs as a pathognomonic feature of the early-onset ovarian cancer Small-cell carcinoma of the ovary, hypercalcemic type. The loss of both catalytic subunits is also described in other rare undifferentiated neoplasms including Thoracic SMARCA4-deficient undifferentiated tumors, Malignant rhabdoid tumors and dedifferentiated or undifferentiated carcinomas, predominantly of lung, gastrointestinal, and endometrial origin. This review provides the first extensive characterization of cancers with concurrent SMARCA4 and SMARCA2 loss through the discussion of shared clinical and molecular features. Further, we discuss the mechanisms triggering the loss of catalytic activity, the cellular processes that are dysfunctional as a consequence, and finally, current therapeutic candidates which may selectively target these cancers.

Melatonin alleviates progression of uterine endometrial cancer by suppressing estrogen/ubiquitin C/SDHB-mediated succinate accumulation

Succinate is an important intermediate of the tricarboxylic acid cycle. Recently discovered roles of succinate demonstrate its involvement in immunity and cancer biology; however, the precise underlying mechanisms of its involvement in these additional roles remain to be determined. In the present study, succinate dehydrogenase (SDH) B was decreased in uterine endometrial cancer cells (UECC) under negative regulation of estrogen. This decrease was the result of lower expression levels of ubiquitin C (UBC), which was associated with the activation of peroxisome proliferator-activated receptor gamma and specificity protein 1. The decreased levels of SDHB resulted in the accumulation of succinate in UECC, and thus, a decrease in the production of fumaric acid. Succinate downregulated voltage-gated potassium channel subfamily Q member 1 (KCNQ1) levels by activating serum/glucocorticoid regulated kinase 1 and promoted the growth of UECC in vitro and in vivo. Treatment with melatonin restricted estrogen/UBC/SDHB-induced succinate accumulation and upregulated expression of KCNQ1 and reduced the succinate-mediated growth of UECC in vitro and in vivo. Furthermore, overexpression of melatonin receptor 1B amplified the inhibitory effects of melatonin on succinate-mediated UECC growth. Together, the data in the present study suggest that melatonin suppresses UECC progression by inhibiting estrogen/UBC/SDHB-induced succinate accumulation. The present study provides a scientific basis for potential therapeutic strategies and targets in UEC, particularly for patients with abnormally low levels of SDHB.

The Megacomplex protects ER-alpha from degradation by Fulvestrant in epithelial ovarian cancer

Ovarian cancer, a significant contributor to cancer-related mortality, exhibits limited responsiveness to hormonal therapies targeting the estrogen receptor (ERα). This study aimed to elucidate the mechanisms behind ERα resistance to the therapeutic drug Fulvestrant (ICI182780 or ICI). Notably, compared to the cytoplasmic version, nuclear ERα was minimally degraded by ICI, suggesting a mechanism for drug resistance via the protective confines of the nuclear substructures. Of these substructures, we identified a 1.3 MDa Megacomplex comprising transcription factors ERα, FOXA1, and PITX1 using size exclusion chromatography (SEC) in the ovarian cancer cell line, PEO4. ChIP-seq revealed these factors colocalized at 6775 genomic positions representing sites of Megacomplex formation. Megacomplex ERα exhibited increased resistance to degradation by ICI compared to cytoplasmic and nuclear ERα. A small molecule inhibitor of active chromatin and super-enhancers, JQ1, in combination with ICI significantly enhanced ERα degradation from Megacomplex as revealed by SEC and ChIP-seq. Interestingly, this combination degraded both the cytoplasmic as well as nuclear ERα. Pathway enrichment analysis showed parallel results for RNA-seq gene sets following Estradiol, ICI, or ICI plus JQ1 treatments as those defined by Megacomplex binding identified through ChIP-seq. Furthermore, similar pathway enrichments were confirmed in mass-spec analysis of the Megacomplex macromolecule fractions after modulation by Estradiol or ICI. These findings implicate Megacomplex in ERα-driven ovarian cancer chromatin regulation. This combined treatment strategy exhibited superior inhibition of cell proliferation and viability. Therefore, by uncovering ERα's resistance within the Megacomplex, the combined ICI plus JQ1 treatment elucidates a novel drug treatment vulnerability.

A novel dual-effect bimodal chip cancer research platform: Chips system interconnected vascularized tumor organoids culture with real-time exploration and detection from bench to bedside

Nowadays, cancer researches widely employed organoids as research model. Organoids provide a realistic applicate scene but how to real-time detect and quantified the organoid status is still a bottleneck. To bridge this knowledge gap, we developed an all-in-one microfluidic platform that, for the first time, seamlessly integrates a vascularized tumor organoids-on-a-chip model (VOoC) with a real-time ELISA detection module for advanced tumor research and point of care testing (POCT). The platform features a unique integration of two cutting-edge technologies: (1) VOoC consists of a perfusable self-forming vessel network throughout the tumor organoid, emulates in vivo tumor angiogenesis, and (2) a real-time microfluidic diagnostic chip equipped with ELISA for simultaneously monitoring of tumor biomarker expression levels. We demonstrated the platform's capabilities using cervical cancer organoids and evaluated the drug efficacy of cisplatin and bevacizumab. This coupled system enables simultaneous tumor microenvironment modeling and continuous, real-time monitoring of secreted biomarkers, a capability not achievable with conventional disconnected systems. By combining these two systems, our dual-effect bimodal chip platform holds great promise for advancing personalized medicine and cancer research, offering a powerful tool for both drug screening and quick diagnosis.

Cervical Cancer Incidence and Mortality Trends in China: The Role of Screening

In China, cervical cancer incidence and mortality have continued to increase despite more than 15 years of nationwide organized screening, raising questions about the population-level impact of screening. Using national cancer registry data from 2004 to 2018, we analyzed temporal trends in age-standardized incidence rates (ASIRs) and mortality rates (ASMRs), as well as age-specific rates, using Joinpoint regression, and assessed their correlations with age-specific screening coverage. From 2004 to 2018, ASIR increased from 6.06 to 11.81 per 100,000, but the annual growth rate slowed markedly after 2007, declining from 12.5 % (95 % CI: 9.7 ∼ 15.5 %) to 3.1 % (95 % CI: 2.7 ∼ 3.4 %). Among women aged 35-44 years, incidence trends shifted from a sharp rise to a sustained decline. By contrast, ASMR rose steadily from 2.07 to 3.44 per 100,000, with an average annual increase of 4.1 % (95 % CI: 3.4 ∼ 4.8 %). Notably, mortality stabilized after a rapid early rise among women aged 40-44 years, the group with the highest screening coverage. Correlation analysis revealed strong positive associations between higher screening coverage and the deceleration of incidence (ρ = 0.85, p < 0.001) and mortality trends (ρ = 0.69, p = 0.014). These findings suggest that increased screening coverage may already be moderating incidence and mortality trends in specific age groups, particularly women aged 35-44 years. However, nationwide declines have yet to emerge, especially in rural populations where screening coverage remains low and disease burden is high. Expanding access and improving screening quality are critical to accelerate progress toward cervical cancer control in China.

Deciphering a GPCR-lncrna-miRNA nexus: Identification of an aberrant therapeutic target in ovarian cancer

Ovarian cancer ranks as a leading cause of mortality among gynecological malignancies, primarily due to the lack of early diagnostic tools, effective targeted therapy, and clear understanding of disease etiology. Previous studies have identified the pivotal role of Lysophosphatidic acid (LPA)-signaling in ovarian cancer pathobiology. Our earlier transcriptomic analysis identified Urothelial Carcinoma Associated-1 (UCA1) as an LPA-stimulated long non-coding RNA (lncRNA). In this study, we elucidate the tripartite interaction between LPA-signaling, UCA1, and let-7 miRNAs in ovarian cancer progression. Results show that the elevated expression of UCA1 enhances cell proliferation, invasive migration, and therapy resistance in high-grade serous ovarian carcinoma cells, whereas silencing UCA1 reverses these oncogenic phenotypes. UCA1 expression inversely correlates with survival outcomes and therapy response in ovarian cancer clinical samples, underscoring its prognostic significance. Mechanistically, UCA1 sequesters let-7 miRNAs, effectively neutralizing their tumor-suppressive functions involving key oncogenes such as Ras and c-Myc. More significantly, intratumoral delivery of UCA1-specific siRNAs inhibits the growth of cisplatin-refractory ovarian cancer xenografts, demonstrating the therapeutic potential of targeting LPAR-UCA1-let-7 axis in ovarian cancer. Thus, our results identify LPAR-UCA1-let-7 axis as a novel avenue for targeted treatment strategies.

A small molecule targeting the interaction between human papillomavirus E7 oncoprotein and cellular phosphatase PTPN14 exerts antitumoral activity in cervical cancer cells

Human papillomavirus (HPV)-induced cancers still represent a major health issue for worldwide population and lack specific therapeutic regimens. Despite substantial advancements in anti-HPV vaccination, the incidence of HPV-related cancers remains high, thus there is an urgent need for specific anti-HPV drugs. The HPV E7 oncoprotein is a major driver of carcinogenesis that acts by inducing the degradation of several host factors. A target is represented by the cellular phosphatase PTPN14 and its E7-mediated degradation was shown to be crucial in HPV oncogenesis. Here, by exploiting the crystal structure of E7 bound to PTPN14, we performed an in silico screening of small-molecule compounds targeting the C-terminal CR3 domain of E7 involved in the interaction with PTPN14. We discovered a compound able to inhibit the E7/PTPN14 interaction in vitro and to rescue PTPN14 levels in cells, leading to a reduction in viability, proliferation, migration, and cancer-stem cell potential of HPV-positive cervical cancer cells. Mechanistically, as a consequence of PTPN14 rescue, treatment of cancer cells with this compound altered the Yes-associated protein (YAP) nuclear-cytoplasmic shuttling and downstream signaling. Notably, this compound was active against cervical cancer cells transformed by different high-risk (HR)-HPV genotypes indicating a potential broad-spectrum activity. Overall, our study reports the first-in-class inhibitor of E7/PTPN14 interaction and provides the proof-of-principle that pharmacological inhibition of this interaction by small-molecule compounds could be a feasible therapeutic strategy for the development of novel antitumoral drugs specific for HPV-associated cancers.

Enhanced extrinsic apoptosis of therapy-induced senescent cancer cells using a death receptor 5 (DR5) selective agonist

Genotoxic agents are widely used anti-cancer therapies because of their ability to interfere with highly proliferative cells. An important outcome of these interventions is the induction of a state of permanent arrest also known as cellular senescence. However, senescent cancer cells are characterized by genomic instability and are at risk of escaping the growth arrest to eventually facilitate cancer relapse. The tumor necrosis factor related apoptosis inducing ligand (TRAIL) signals extrinsic apoptosis via Death Receptors (DR) 4 and 5, while Decoy Receptors (DcR) 1 and 2, and Osteoprotegerin (OPG) are homologous to death receptors but incapable of transducing an apoptotic signal. The use of recombinant TRAIL as an anti-cancer strategy in combination with chemotherapy is currently in development, and a major question remains whether senescent cancer cells respond to TRAIL. Here, we show variable sensitivity of cancer cells to TRAIL after senescence induction, and upregulation of both pro-apoptotic and anti-apoptotic receptors in therapy-induced senescent cancer cells. A DR5-selective TRAIL variant (DHER), unable to bind to DcR1 or OPG, was more effective in inducing apoptosis of senescent cancer cells compared to wild-type TRAIL. Importantly, no apoptosis induction was observed in non-cancerous cells, even at the highest concentrations tested. Our results suggest that targeting DR5 can serve as a novel therapeutic strategy for the elimination of therapy-induced senescent cancer cells.

Neutrophil extracellular traps enhance platinum resistance in ovarian cancer via SHP-1 activation

Platinum resistance continues to be a major therapeutic challenge in ovarian cancer, driving disease recurrence and limiting patient survival. In this study, we identify a significant enrichment of neutrophil extracellular traps (NETs) within the tumor microenvironment of platinum-resistant ovarian tumors. These NETs actively contribute to malignant progression by promoting epithelial-mesenchymal transition and fostering chemotherapy resistance. Mechanistically, we demonstrate that NETs drive chemoresistance through the unexpected activation of SHP-1. Although traditionally recognized as a tumor suppressor, SHP-1 assumes an oncogenic function in this context. Specifically, NETs trigger TGF-β signaling, resulting in Smad2 phosphorylation, which subsequently promotes both the enzymatic activation and nuclear translocation of SHP-1. Once in the nucleus, SHP-1 enhances RNA polymerase II-mediated transcription and nucleotide excision repair, ultimately enabling cancer cells to evade cisplatin-induced cytotoxicity. Our in vivo experiments corroborate these findings that elevated NETs levels exhibit poor response to cisplatin, while pharmacological inhibition of NETs effectively restores drug sensitivity. This study not only advances our understanding of microenvironment-driven drug resistance but also highlights the therapeutic potential of targeting the NETs/SHP-1 axis to overcome platinum resistance in ovarian cancer.

HPV-induced Nurr1 promotes cancer aggressiveness, self-renewal, and radioresistance via ERK and AKT signaling in cervical cancer

Human papillomavirus (HPV) is the etiological agent of cervical cancer; however, the mechanisms underlying HPV-mediated carcinogenesis remain poorly understood. Here, we showed that nuclear receptor related-1 protein (Nurr1) was upregulated in primary cervical cancer tissue-derived spheroid cells and HPV-positive cell lines, and Nurr1 upregulation was correlated with cancer grade. Nurr1 promoted cell proliferation, migration, invasion, and anchorage-independent cell growth. In addition to its effect on cancer aggressiveness, Nurr1 enhanced the self-renewal ability of cells in vitro and in vivo, underscoring the importance of Nurr1 in maintaining the stemness of cancer stem-like cells (CSLCs). Mechanistically, Nurr1 independently activated the MEK/ERK and PI3K/Akt/mTOR signaling cascades. The MEK inhibitor trametinib (GSK) and PI3K/mTOR dual inhibitor dactolisib (BEZ) were shown to abrogate Nurr1-augmented tumorigenesis by upregulating p21 and p27 expression and by suppressing MMP9 and KLF4 expression. We provided further evidence that BEZ, but not GSK, could abolish Nurr1-enhanced radioresistance, suggesting its potential value for radiosensitizing CSLCs in the clinical setting. This study highlights the unprecedented roles of Nurr1 and elucidates mechanisms by which Nurr1 promotes tumor progression and radioresistance, providing a novel therapeutic strategy for cervical cancer treatment.

An SGLT2 inhibitor modulates SHH expression by activating AMPK to inhibit the migration and induce the apoptosis of cervical carcinoma cells

In addition to their hypoglycemic effect, sodium-glucose cotransporter 2 (SGLT2) inhibitors have many other benefits. In the present study, we examine the anticancer effect of the SGLT2 inhibitor empagliflozin using cervical carcinoma models. In vivo antitumor activities of empagliflozin were observed in a nude mouse model. Empagliflozin intervention and downregulation of Sonic Hedgehog Signaling Molecule (Shh) inhibited the migration and promoted the apoptosis of cervical cancer cells in nude mice. Compared with the control group, the empagliflozin treatment group had an increased level of AMP-activated protein kinase (AMPK) and decreased levels of Forkhead Box A1 (FOXA1) and SHH in tumor tissue. In vitro experiments also showed that empagliflozin (50 μM) inhibited the migration of cervical cancer cells and induced their apoptosis by activating the AMPK/FOXA1 pathway and inhibiting the expression of SHH. Kaplan-Meier survival analysis was used to determine the relationship between SHH expression and total survival time. The results showed that in cervical cancer patients, high SHH expression resulted in unfavorable overall survival. The downregulation of SHH with small interfering RNA (siRNA) inhibited the migration and invasion and promoted the apoptosis of HeLa cells. These findings show that empagliflozin has a potential therapeutic effect on cervical cancer. This effect was related to the activation of the AMPK pathway and the inhibition of SHH expression.

Publisher

Elsevier BV

ISSN

0304-3835