Current Cancer Drug Targets

Comprehensive Analyses and Experiments Confirmed IGFBP5 as a Prognostic Predictor Based on an Aging-genomic Landscape Analysis of Ovarian Cancer

Background:: Ovarian cancer (OC) is one of the malignant diseases of the reproductive system in elderly women. Aging-related genes (ARGs) were involved in tumor malignancy and cellular senescence, but the specifics of these mechanisms in OC remain unknown. Methods:: ARGs expression and survival data of OC patients were collected from TCGA and CPTAC databases. Subtype classification was used to identify the roles of hub ARGs in OC progression, including function enrichment, immune infiltration, and drug sensitivity. LASSO regression was utilized to confirm the prognosis significance for these hub ARGs. MTT, EdU, Transwell, and wounding healing analysis confirmed the effect of IGFBP5 on the proliferation and migration ability of OC cells. Results:: ARGs were ectopically expressed in OC tissues compared to normal ovary tissues. Three molecular subtypes were divided by ARGs for OC patients. There were significant differences in ferroptosis, m6A methylation, prognosis, immune infiltration, angiogenesis, differentiation level, and drug sensitivity among the three groups. LASSO regression indicated that 4 signatures, FOXO4, IGFBP5, OGG1 and TYMS, had important prognosis significance. Moreover, IGFBP5 was significantly correlated with immune infiltration. The hub ARG, IGFBP5, expression was significantly decreased in OC patients compared to normal women. IGFBP5 could also reduce the migration and proliferation ability of OC cells compared to vector and NC groups. Conclusion:: IGFBP5 was correlated with OC prognosis and associated with OC migration and proliferation. This gene may serve as potential prognostic biomarkers and therapeutic targets for OC patients.

A Novel Platinum-Resistance-related Gene Signature in Ovarian Cancer: Identification and Patient-derived Organoids Verification

Background: Platinum-based chemotherapy resistance is one of the main contributors to the mortality of Ovarian Cancer (OC). It is believed that sensitive biomarkers for identifying the population that is platinum-resistant are urgently needed. This study aims to develop a platinum-resistance gene-based signature to predict OC patients' responses to platinum drugs as well as survival outcomes. Methods: A platinum-resistance-related gene model was built by bioinformatics analysis. Then, its predictive power was internally validated. Continually, a nomogram was constructed to confirm the model's predictive ability. Afterward, GSEA was used to explore our model's potential functions. The ESTIMATE, CIBERSORT, TIMER, and ssGSEA were applied to estimate immune conditions. Then, somatic mutation and drug sensitivity were also analyzed. Finally, to gain insights into the roles of targeted genes in drug sensitivity, patient-derived tumor organoids (PDOs) validation was performed. Results: Nine platinum-resistance-related genes, including SLC22A2, TAP1, PC, MCM3, GTF2H2, FXYD5, SUPT6H, IGKC, and MATN2, were anchored to build the predictive model, which was well internally validated. Subsequently, GSEA unveiled that our model genes enriched in the Hedgehog signaling pathway. The predictive signature was associated with immune checkpoint inhibitors such as PD-1, PD-L1, and CTLA4, guiding immunotherapy applications for OC patients. Drugs such as dasatinib, midostaurin, metformin, MK-2206, and mitomycin C might also benefit OC patients with different risk scores. PDOs showed patients with high-risk scores were more resistant to cisplatin than patients with low-risk scores. Conclusion: The platinum-resistance-related gene signature (SLC22A2, TAP1, PC, MCM3, GTF2H2, FXYD5, SUPT6H, IGKC, and MATN2) is valuable for prognosis prediction and guidance of treatment choices for OC patients

The Plasticity of Circulating Tumor Cells in Ovarian Cancer During Platinum-containing Chemotherapy

Background: Circulating Tumor Cells (CTCs) are a potential source of metastases and relapses. The data on molecular characteristics of Ovarian Cancer (OC) CTCs are limited. Objective: This study aims to assess the TGFβ, CXCL2, VEGFA and ERCC1 expressions in two OC CTC subpopulations before and during chemotherapy (CT), and their relation to clinical characteristics. Methods: Two CTCs subpopulations (EpCAM+CK18+E-cadherin+; EpCAM+CK18+Vimentin+) were enriched using immunomagnetic separation before treatment and after 3 cycles of platinumcontaining CT. The expression of mRNA was assessed using RT-qPCR. Results: The study included 31 I-IV stage OC patients. During CT, TGFβ levels increased in both fractions (p=0.054) compared with the initial levels. ERCC1 expression in E-cadherin+ CTCs was higher during neoadjuvant than adjuvant CT (p=0.004). CXCL2 level in E-cadherin+ CTCs increased (p=0.038) during neoadjuvant CT compared with the initial. TGF-β expression in vimentin+ CTCs during CT was negatively correlated to disease stage (p=0.003). Principal component analysis before CT revealed a component combining VEGFA, TGFβ, CXCL2, and a component with ERCC1 and VEGFA; during CT, component 1 contained ERCC1 and VEGFA, and component 2 - TGFβ and CXCL2 in both fractions. Increased ERCC1 expression in E-cadherin+ CTCs during CT was associated with decreased Progression-Free Survival (PFS) (HR 1.11 (95% CI 1.03-1.21, p=0.009) in multivariate analysis. Conclusion: EpCAM+ OC CTCs are phenotypically heterogeneous, which may reflect variability in their metastatic potential. CT changes the molecular characteristics of CTCs. Expression of TGFβ in EpCAM+ CTCs increases during CT. High ERCC1 expression in EpCAM+CK18+E-cadherin+ CTCs during CT is associated with decreased PFS in OC.

Real-world Study on the Effect of PARPi as Maintenance Therapy on Platinum Sensitivity after First- and Second-line Chemotherapy in Patients with Recurrent High-grade Serous Epithelial Ovarian Cancer

Background: This study investigated the effect of poly(ADP-ribose) polymerase inhibitors (PARPi) as maintenance therapy after first- and second-line chemotherapy on platinum sensitivity in patients with recurrent high-grade serous epithelial ovarian cancer (rHGSOC). Methods: This study retrospectively analyzed 172 patients with rHGSOC treated at Zhejiang Cancer Hospital and Jiaxing Maternity and Child Health Care Hospital between January 2017 and December 2021. The 1st-PARPi group comprised patients who received a PARPi as maintenance therapy after first-line chemotherapy (n=23), and the 1st-control group comprised those who did not (n = 105). Similarly, the 2nd-PARPi group comprised patients not given a PARPi in their first-line treatment (n = 30), and the 2nd-control group comprised those who were given a PARPi (n = 89). Results: Among the 23 patients in the 1st-PARPi group and the 105 patients in the 1st-control group, nine and 99 were platinum-sensitive, and 14 and six were platinum-resistant, respectively (hazard ratio [HR]: 14.46, P < 0.0001). Among the 30 patients in the 2nd-PARPi group and 89 patients in the 2nd-control group, 10 and 71 were platinum-sensitive, and 20 and 18 were platinumresistant, respectively (HR: 4.37, P < 0.0001). Age, stage, residual tumor, the courses of platinumbased chemotherapy, and breast cancer susceptibility gene mutations were not associated with platinum sensitivity when using a PARPi as maintenance therapy after first- and second-line chemotherapy. Conclusion: Patients with rHGSOC using a PARPi were more likely to be platinum-sensitive and develop platinum resistance independent of PARPi duration. Care should be taken when using a PARPi as maintenance therapy after first- and second-line chemotherapy.

Targeting Six Hallmarks of Cancer in Ovarian Cancer Therapy

Normal cells must overcome multiple protective mechanisms to develop into cancer cells. Their new capabilities include self-sufficiency in growth signals and insensitivity to antigrowth signals, evasion of apoptosis, a limitless replicative potential, sustained angiogenesis, and tissue invasion and metastasis; these are also termed the six hallmarks of cancer. A deep understanding of the genetic and protein alterations involved in these processes has enabled the development of targeted therapeutic strategies and clinical trial design in the search for ovarian cancer treatments. Clinically, significantly longer progression-free survival has been observed in the single use of PARP, MEK, VEGF and Chk1/Chk2 inhibitors. However, the clinical efficacy of the targeted agents is still restricted to specific molecular subtypes and no trials illustrate a benefit in overall survival. Exploring novel drug targets or combining current feasible biological agents hold great promise to further improve outcomes in ovarian cancer. In this review, we intend to provide a comprehensive description of the molecular alterations involved in ovarian cancer carcinogenesis and of emerging biological agents and combined strategies that target aberrant pathways, which might shed light on future ovarian cancer treatment.

Oncolytic Adenovirus H101 Synergizes with Radiation in Cervical Cancer Cells

Background:: A major challenge in cervical cancer radiotherapy is tailoring the radiation doses efficiently to eliminate malignant cells and reduce the side effects in normal tissues. Oncolytic adenovirus drug H101 was recently tested and approved as a topical adjuvant treatment for several malignancies. Objective: This study aimed to evaluate the potential neoadjuvant radiotherapy benefits of H101 by testing the inhibitory function of H101 in combination with radiation in different cervical cancer cells. Methods: Human cervical cancer cell lines C33a, SiHa, CaSki, and HeLa were treated with varying concentrations of H101 alone or in combination with radiation (2 Gy or 4 Gy). Cell viability and apoptosis were measured at the indicated time intervals. HPV16 E6 and cellular p53 mRNA expression alteration was measured by qRT-PCR. In situ RNA scope was used to determine HPV E6 status. P53 protein alterations were detected by Western blot. Results: Cell viability and apoptosis assays revealed that the combination of a high dose of H101 (MOI=1000, 10000) with radiation yielded a synergistic anticancer effect in all tested cervical cancer cell lines (P<0.05), with the greatest effect achieved in HPV-negative C33a cells (P<0.05). Low-HPV16-viral-load SiHa cells were more sensitive to the combination therapy than high-HPV16- viral-load CaSki cells (P<0.05). The combined treatment reduced HPV16 E6 expression and increased cellular P53 levels compared to those observed with radiation alone in SiHa and CaSki cells (P<0.05). Conclusions: Oncolytic adenovirus H101 effectively enhances the antitumor efficacy of radiation in cervical cancer cells and may serve as a novel combination therapy for cervical cancer.

Targeted Biological Effect of An Affitoxin Composed of an HPV16E7 Affibody Fused with Granzyme B (ZHPV16E7-GrB) Against Cervical Cancer In vitro and In vivo

Background: High risk type 16 of human papillomavirus (HPV16) is associated with 50% of cervical cancer, for which reliable targeted therapies are lacking. HPV early protein 7 (E7) is an oncoprotein responsible for cell malignant transformation. In our previous work, a highly specific affibody targeting HPV16E7 (ZHPV16E7) was developed. Objective: In order to improve the targeted therapeutic effect, the present study prepared an affitoxin consisting of ZHPV16E7 fused with granzyme B (GrB), namely, ZHPV16E7-GrB, and evaluated its targeting action in vitro and in vivo. Methods: The ZHPV16E7-GrB fusion protein was produced in a prokaryotic expression system. The targeted binding properties of the ZHPV16E7-GrB to the HPV16E7 were confirmed by immunofluorescence assay (IFA) in cervical cancer cell lines, by immunohistochemical assay (IHA) in cervical cancer tissue from clinical specimens and by near-infrared imaging in tumour-bearing mice. The anti- tumour effect on both cervical cancer cells in vitro and tumour-bearing mice in vivo were further evaluated. Results: A 34-kDa ZHPV16E7-GrB fusion protein was produced in E. coli and displayed the corresponding immunoreactivity. IFA revealed that ZHPV16E7-GrB bound specifically to HPV16-positive TC-1 and SiHa cells. IHA showed that ZHPV16E7-GrB also bound specifically to HPV16-positive clinical tissue specimens. In addition, the near-infrared imaging results showed that ZHPV16E7-GrB was enriched in tumour tissues. Moreover, both the ZHPV16E7-GrB affitoxin and ZHPV16E7 affibody (without GrB) significantly reduced the proliferation of cervical cancer cells in vitro and tumor-bearing mice in vivo, and the anti-proliferative effect of ZHPV16E7-GrB was higher than that of the ZHPV16E7 affibody. Conclusions: The affitoxin by coupling the affibody with GrB is a promising targeted therapeutic agent with the dual advantages of the targeted affibody and the GrB cytotoxin.

Hypermethylation of Single CpG Dinucleotides at the Promoter of CXCL13 Gene Promoting Cell Migration in Cervical Cancer

Background: Chemokine 13 (CXCL13) and its chemokine receptor 5 (CXCR5) are involved in the onset of various types of cancer. However, their role in cervical cancer (CC) remains unknown. Objective: To investigate the role of chemokine 13 (CXCL13) and its receptor in CC. Methods: The expression of CXCL13/CXCR5 and the infiltration of CXCR5+CD8+ T cells in CC, cervical intraepithelial neoplasia (CIN), normal cervical epithelial (NCE) tissues, and in CC cell lines were analysed and the associated clinical significance was determined. In vitro, CXCL13 overexpression and DNA methyltransferase inhibition (through S110) were used to investigate the biological function and the underlying mechanism that regulates CXCL13 expression. Tumor growth and liver metastasis were also evaluated in the xenogenous subcutaneously implant model. Results: CXCL13/CXCR5 expression levels and the infiltration of CXCR5+CD8+ T cells were significantly decreased in CC tissues compared with CIN and NCE tissues. CXCL13 downregulation was significantly correlated with the FIGO stages, lymph node metastasis, interstitial infiltration depth, and pathological grade. The overexpression of CXCL13 suppressed CC cell migration. CXCL13 downregulation was associated with hypermethylation in CC cell lines, and primary tumor biopsies. Furthermore, a CpG dinucleotide at the HIF-1a transcription factor motifs in the promoter element of CXCL13 was consistently methylated in CC cells and associated with HIF-1a. CXCL13 overexpression and S110 treatment dramatically repressed tumor growth and liver metastasis in the xenograft model; whereas it’s low expression increased the risk of death in CC patients. Conclusion: DNA methylation-dependent CXCL13 downregulation may promote cervical carcinogenesis and progression.

Promotion of Cervical Cancer Cell Proliferation by miR-130b Expression Level Changes and Inhibition of its Apoptosis by Targeting CDKN1A Gene

Background: Dysregulation of miR-130b expression is associated with the development of different cancers. However, the description of the biological roles of miR-130b in the growth and survival of cervical cancer cells is limited. Method: The miR-130b levels in cervical cancer cells during different stages of growth were determined using reverse transcription-quantitative PCR. The methylation level of DNA sequences upstream of the miR-130b gene was measured using an SYBR Green-based quantitative methylation- specific PCR. Reverse transcription-quantitative PCR, Western blotting, and fluorescence report assays were used to identify the miR-130b-targeted gene. Cell counting kit-8 and comet assays were used to determine cell viability and DNA damage levels in cells, respectively. EdU Apopllo488 In Vitro Flow Cytometry kit, propidium iodide staining, anti-γ-H2AX antibody staining, and Annexin-V apoptosis kit were subsequently used to determine DNA synthesis rates, cell cycle distribution, count of DNA double-strand breaks, and levels of apoptotic cells. Result: miR-130b levels increased at exponential phases of the growth of cervical cancer cells but reduced at stationary phases. The methylation of a prominent CpG island near the transcript start site suppressed the miR-130b gene expression. MiR-130b increased cell viability, promoted both DNA synthesis and G1 to S phase transition of the cells at exponential phases, but reduced cell viability accompanied by accumulations of DNA breaks and augmentations in apoptosis rates of the cells in stationary phases by targeting cyclin-dependent kinase inhibitor 1A mRNA. Conclusion: miR-130b promoted the growth of cervical cancer cells during the exponential phase, whereas it impaired the survival of cells during stationary phases.

Strategic Combination Therapies for Ovarian Cancer

Ovarian cancer remains the leading cause of gynecologic cancer-related deaths among women worldwide. The dismal survival rate is partially due to recurrence after standardized debulking surgery and first-line chemotherapy. In recent years, targeted therapies, including antiangiogenic agents or poly (ADP-ribose) polymerase inhibitors, represent breakthroughs in the treatment of ovarian cancer. As more therapeutic agents become available supplemented by a deeper understanding of ovarian cancer biology, a range of combination treatment approaches are being actively investigated to further improve the clinical outcomes of the disease. These combinations, which involve DNA-damaging agents, targeted therapies of signaling pathways and immunotherapies, simultaneously target multiple cancer pathways or hallmarks to induce additive or synergistic antitumor activities. Here we review the preclinical data and ongoing clinical trials for developing effective combination therapies in treating ovarian cancer. These emerging therapeutic modalities may reshape the treatment landscape of the disease.

USP48 Sustains Chemoresistance and Metastasis in Ovarian Cancer

Background: Ubiquitin specific protease 48 (USP48) is a member of the deubiquitinating enzymes (DUBs) family. However, the function of USP48 in ovarian cancer remains unclear. Objective: The present study reveals that USP48 knockdown could significantly inhibit cell migration and invasion in ES2, 3AO and A2780 cells, without affecting cell proliferation. Methods: After carboplatin (CBP) treatment, the USP48 ablation increases the apoptosis rate, and the cleaved PARP and cleaved caspase 3 expression levels in ES2, 3AO and A2780 cells. The subcutaneous tumor and intraperitoneally injected experiments demonstrated that the USP48 knockdown significantly increases responsiveness to CBP, and alleviates the metastasis in vivo. Meanwhile, USP48 deficiency results in the improved survival of mice. Results: Finally, the analysis of clinical samples and the TCGA and Kaplan-Meier Plot database revealed that the high expression of USP48 in ovarian cancer patients is associated with poor survival and resistance to CBP therapy. Conclusion: In summary, USP48 may be a potential therapeutic target for ovarian cancer patients.

Development of CDK12 as a Cancer Therapeutic Target and Related Inhibitors

Cyclin-dependent Kinase 12 (CDK12) is a Cyclin-dependent Kinase (CDK) that plays a crucial role in various biological processes, including transcription, translation, mRNA splicing, cell cycle regulation, and DNA damage repair. Dysregulation of CDK12 has been implicated in tumorigenesis, and genetic alterations affecting CDK12 have been identified in multiple cancer types, including breast cancer, ovarian cancer, gastric cancer, and prostate cancer. Numerous studies have demonstrated that suppression of CDK12 expression effectively inhibits tumor growth and proliferation, underscoring its significance as a cancer biomarker and a potential therapeutic target in cancer treatment. A thorough comprehension of CDK12 is expected to significantly enhance the advancement of novel approaches for the treatment and prevention of cancer. In recent times, endeavors have been undertaken to formulate targeted inhibitors for CDK12, such as PROTAC and molecular gel degraders. Concurrently, investigations have been conducted on the combined utilization of CDK12 small molecule inhibitors and immunotherapy as a potential strategy. This paper examines the diverse functions of CDK12 in the modulation of gene expression and its implications in human tumors. Specifically, it explores the recently uncovered roles of CDK12 kinases in various cellular processes, emphasizing the potential of CDK12 as a viable therapeutic target for the management of human tumors. Furthermore, this review provides an up-to-- date account of the advancements made in utilizing CDK12 in tumor therapy.

Recent Progress in the Application of Exosome Analysis in Ovarian Cancer Management

Abstract: Exosomes are very small (nano-sized) vesicles participating in tumor development by involvement in intercellular communication mediated by transferring biocomponents. Exosomes appear to play vital roles in various cancer development, such as ovarian cancer, a common malignancy in women. Several hallmarks of ovarian cancer are reported to be affected by the exosome-- mediated cellular cross-talk, including modulating peritoneal dissemination and chemoresistance. Since the expression of some biomolecules, such as miRNAs and mRNA, is changed in ovarian cancer, these exo-biomolecules can be applied as prognostic, diagnostic, and therapeutic biomarkers. Also, the selective loading of specific chemotherapeutic agents into exosomes highlights these biocarries as potential delivery devices. Exosomes could be artificially provided and engineered to better target the site of interest in ovarian cancer. In the present review, we summarize the notable achievement of exosome application in ovarian cancer management to gain applicable transitional insight against this cancer.