Human Epithelial Ovarian Cancer Research Articles

Injectable bio-multifunctional hyaluronic acid-based hydrogels loaded with poly ADP-ribose polymerase inhibitors for ovarian cancer therapy

The recent use of PARP inhibitors (PARPi) in the maintenance treatment of ovarian tumor has significantly improved the survival rates of cancer patients. However, the current oral administration of PARP inhibitors fails to realize optimal therapeutic effects due to the low bioavailability in cancerous tissues, and often leads to a range of systemic adverse effects including hematologic toxicities, digestive system reactions, and neurotoxicities. Therefore, the demand for an advanced drug delivery system that can ensure effective drug administration while minimizing these unfavorable reactions is pressing. Injectable hydrogel emerges as a promising solution for local administration with the capability of sustainable drug release. In this study, we developed an injectable hydrogel made from aminated hyaluronic acid and aldehyde-functionalized pluronic127 via Schiff base reaction. This hydrogel exhibits excellent injectability with short gelation time and remarkable self-healing ability, and is applied to load niraparib. The drug-loaded hydrogel (HP@Nir hydrogel) releases drugs sustainably as tested in vitro as well as displays significant anti-proliferation and anti-migratory properties on human epithelial ovarian cancer cell line. Notably, HP@Nir hydrogel effectively suppresses the growth of ovarian cancer, without significant adverse reactions as demonstrated in animal studies. Additionally, the developed hydrogel is gradually degraded in vivo for around 20 d, while maintaining good biocompatibility. Overall, the injectable hydrogel loaded with niraparib provides a secure and efficient strategy for the treatment and management of ovarian cancer.

Circ-RNF111 Promotes Proliferation of Ovarian Cancer Cell SKOV-3 by Targeting the MiR-556-5p/CCND1 Axis.

The aim of this study was to investigate the role and mechanism of circ-RNF111 in the human ovarian cancer cell line SKOV-3. First, qRT-PCR was used to detect circ-RNF111 and miR-556-5p expression levels in human normal ovarian epithelial cells IOSE80 and human ovarian cancer cells SKOV-3. CCK-8 and colony formation assays were adopted to determine the proliferation rate and cell viability of SKOV-3 cells, respectively. Additionally, in an attempt to reveal the mechanism of circ-RNF111, we predicted the targeting relationship between miR-556-5p and circ-RNF111 as well as miR-556-5p and CCND1 using the circinteractome and TargetScan databases, respectively, and validated their relationship by dual-luciferase reporter assay. The protein expression levels of CCND1 in SKOV-3 cells were detected by Western blot. Based on the above experiments, the expression of circ-RNF111 was found to be up-regulated in SKOV-3, and the knockdown of circ-RNF111 significantly inhibited the proliferation and viability of SKOV-3 cells. Then we confirmed that circ-RNF111 sponged miR-556-5p in SKOV-3 cells to up-regulate CCND1 expression. In addition, simultaneous inhibition of miR-556-5p or overexpression of CCND1 in SKOV-3 cells with knockdown of circ-RNF111 reversed the inhibitory effect of knockdown of circ-RNF111 on the protein expression level of CCND1, cell proliferation rate, and cell viability. In summary, circ-RNF111 promotes the proliferation of SKOV-3 cells by targeting the miR-556-5p/CCND1 axis. Circ-RNF111 may serve as a potential target for ovarian cancer therapy.

Mechanism of Ellagic Acid-Induced Autophagy in Cis-Diamminedichloroplatinum(II)-Resistant Ovarian Cancer Cells

This study investigated the effect of ellagic acid on autophagy in cisplatin-resistant human epithelial ovarian cancer cells. After the autophagy double-labeled mred fluorescence protein, green fluorescence protein, light chain 3 carrying adenovirus infected cisplatin-resistant human epithelial ovarian cancer cells, the changes of autophagy flux and autophagy-related proteins were detected. Cell counting kit-8 assay was employed to detect the viability of cisplatin-resistant human epithelial ovarian cancer cells. The results showed that the number of autophagosomes and autolysosomes in the ellagic acid group increased significantly in comparison with the in cisplatin-resistant human epithelial ovarian cancer group. With the increase in ellagic acid concentration, light chain 3-II/I ratio and Beclin1 expression increased, p62 expression and cell viability decreased, and caspase-3 activated, in cisplatin-resistant human epithelial ovarian cancer cells. Conversely, 3-methyladenine inhibited ellagic acid-induced autophagy and activated caspase-3 and enhanced the cell viability. Similarly, chloroquine significantly increased cell survival rate, light chain 3-II/I ratio, and activated caspase-3, but decreased p62 expression in the ellagic acid group. In conclusion, ellagic acid can induce autophagy to inhibit the proliferation of cisplatin-resistant human epithelial ovarian cancer cells.

Rhamnetin, a nutraceutical flavonoid arrests cell cycle progression of human ovarian cancer (SKOV3) cells by inhibiting the histone deacetylase 2 protein

Overexpression of HDAC 2 promotes cell proliferation in ovarian cancer. HDAC 2 is involved in chromatin remodeling, transcriptional repression, and the formation of condensed chromatin structures. Targeting HDAC 2 presents a promising therapeutic approach for correcting cancer-associated epigenetic abnormalities. Consequently, HDAC 2 inhibitors have evolved as an attractive class of anti-cancer agents. This work intended to investigate the anti-cancer abilities and underlying molecular mechanisms of Rhamnetin in human epithelial ovarian carcinoma cells (SKOV3), which remain largely unexplored. We employed various in vitro methods, including MTT, apoptosis study, cell cycle analysis, fluorescence microscopy imaging, and in vitro enzymatic HDAC 2 protein inhibition, to examine the chemotherapeutic sensitivity of Rhamnetin in SKOV3 cells. Additionally, we conducted in silico studies using molecular docking, MD simulation, MM-GBSA, DFT, and pharmacokinetic analysis to investigate the binding interaction mechanism within Rhamnetin and HDAC 2, alongside the compound’s prospective as a lead candidate. The in vitro assay confirmed the cytotoxic effects of Rhamnetin on SKOV3 cells, through its inhibition of HDAC 2 activity. Rhamnetin, a nutraceutical flavonoid, halted at the G1 phase of the cell cycle and triggered apoptosis in SKOV3 cells. Furthermore, computational studies provided additional evidence of its stable binding to the HDAC 2 protein’s binding site cavity. Based on our findings, we conclude that Rhamnetin effectively promotes apoptosis and mitigates the proliferation of SKOV3 cells through HDAC 2 inhibition. These results highlight Rhamnetin as a potential lead compound, opening a new therapeutic strategy for human epithelial ovarian cancer. Communicated by Ramaswamy H. Sarma

Polystyrene nanoparticle exposure accelerates ovarian cancer development in mice by altering the tumor microenvironment

Microplastics and nanoplastics are ubiquitous pollutants, widely spread in the living and natural environment. Although their potential impact on human health has been investigated, many doubts remain about their effects in carcinogenic processes. We investigated the potential effects and its molecular mechanisms of polystyrene nanoplastics (PS-NPs) on epithelial ovarian cancer (EOC) using the human EOC cell line HEY as an in vitro cell model and mice as a mammalian model. In vivo exposure to PS-NPs (100 nm; 10 mg/L) via drinking water significantly accelerated EOC tumor growth in mice. In in vitro tests the PS-NPs reduced the relative viability of EOC cells in a dose-dependent manner. Histological analysis showed increased mitotic counts in EOC tumor tissues of PS-NP exposed mice. PS-NP exposure significantly affected gene expression and disturbed many metabolic pathways in both cultured EOC cells and EOC tumor tissue in mice. Gene functional and pathway analysis indicated that immune-related responses and the tumor microenvironment pathway were significantly enriched, which may be attributed to disturbed expression of thrombomodulin (THBD) and its regulators. It may be concluded that PS-NP exposure caused a significant acceleration of EOC tumor growth in mice and a dose-dependent decrease in the relative viability of EOC cells by altering the tumor growth microenvironment. This offers new insights into the mechanisms underlying PS-NP effects on EOC.

Endoplasmic Reticulum Stress-Related Ten-Biomarker Risk Classifier for Survival Evaluation in Epithelial Ovarian Cancer and TRPM2: A Potential Therapeutic Target of Ovarian Cancer.

Epithelial ovarian cancer (EOC) is the most lethal gynecological malignant tumor. Endoplasmic reticulum (ER) stress plays an important role in the malignant behaviors of several tumors. In this study, we established a risk classifier based on 10 differentially expressed genes related to ER stress to evaluate the prognosis of patients and help to develop novel medical decision-making for EOC cases. A total of 378 EOC cases with transcriptome data from the TCGA-OV public dataset were included. Cox regression analysis was used to establish a risk classifier based on 10 ER stress-related genes (ERGs). Then, through a variety of statistical methods, including survival analysis and receiver operating characteristic (ROC) methods, the prediction ability of the proposed classifier was tested and verified. Similar results were confirmed in the GEO cohort. In the immunoassay, the different subgroups showed different penetration levels of immune cells. Finally, we conducted loss-of-function experiments to silence TRPM2 in the human EOC cell line. We created a 10-ERG risk classifier that displays a powerful capability of survival evaluation for EOC cases, and TRPM2 could be a potential therapeutic target of ovarian cancer cells.

Pharmacological inhibition of protein kinase D suppresses epithelial ovarian cancer via MAPK/ERK1/2/Runx2 signalling axis

Epithelial ovarian cancer (EOC) is the most lethal gynaecological malignancy with poor prognosis and dismal patient survival. Although protein kinase D (PKD) isoforms, especially PKD2 and PKD3 are critical for many cellular and physiological functions involved in carcinogenesis including cell proliferation and angiogenesis, their role in human EOC remains unknown. Towards the goal to identify novel prognostic biomarker and therapeutic interventions against EOC, this study aimed to elucidate the molecular roles of PKD2, PKD3 and highly selective, pan-PKD inhibitor CRT0066101 in this lethal pathology. Our results indicated that inactivation of PKD2 and PKD3 by 1 μM CRT0066101 suppressed EOC cell proliferation, colony formation, cell migration and invasion. Moreover, CRT0066101 induced apoptosis and inhibited cell cycle at G2-M phase in EOC cells. Genetic knockdown of PKD2 and PKD3 confirmed the anti-carcinogenic effects of CRT0066101 against EOC. The anti-cancer phenotype of EOC cells resulted from CRT0066101-mediated PKD2 and PKD3 inactivation or genetic depletion was, in part, mediated by transcription factor Runx2 as abrogation of PKD2 and PKD3 caused downregulation of Runx2 and its downstream target genes including osteopontin, focal adhesion kinase and ERK1/2. Moreover, overexpression of a constitutively active PKD2 augmented the expression levels of phosphor-ERK1/2T202/Y204, Runx2 and its downstream targets. Mechanistically, PKD2 and PKD3 positively regulated Runx2 via MAPK/ERK1/2 pathway and promoted EOC. Taken together, our results indicated that PKD2/3/ERK1/2/Runx2 signalling axis might be a novel drug target against EOC and CRT0066101 could be developed as a promising therapeutic choice against this lethal pathology.

NPFF stimulates human ovarian cancer cell invasion by upregulating MMP-9 via ERK1/2 signaling

Neuropeptide FF (NPFF) belongs to the RFamide peptide family. NPFF regulates a variety of physiological functions by binding to a G protein-coupled receptor (GPCR), NPFFR2. Epithelial ovarian cancer (EOC) is a leading cause of death among gynecological malignancies. The pathogenesis of EOC can be regulated by many local factors, including neuropeptides, through an autocrine/paracrine manner. However, to date, the expression and/or function of NPFF/NPFFR2 in EOC is undetermined. In this study, we show that the upregulation of NPFFR2 mRNA was associated with poor overall survival in EOC. The TaqMan probe-based RT-qPCR showed that NPFF and NPFFR2 were expressed in three human EOC cells, CaOV3, OVCAR3, and SKOV3. In comparison, NPFF and NPFFR2 expression levels were higher in SKOV3 cells than in CaOV3 or OVCAR3 cells. Treatment of SKOV3 cells with NPFF did not affect cell viability and proliferation but stimulated cell invasion. NPFF treatment upregulates matrix metalloproteinase-9 (MMP-9) expression. Using the siRNA-mediated knockdown approach, we showed that the stimulatory effect of NPFF on MMP-9 expression was mediated by the NPFFR2. Our results also showed that ERK1/2 signaling was activated in SKOV3 cells in response to the NPFF treatment. In addition, blocking the activation of ERK1/2 signaling abolished the NPFF-induced MMP-9 expression and cell invasion. This study provides evidence that NPFF stimulates EOC cell invasion by upregulating MMP-9 expression through the NPFFR2-mediated ERK1/2 signaling pathway.

Efficacy of HER2-Targeted Intraperitoneal 225Ac α-Pretargeted Radioimmunotherapy for Small-Volume Ovarian Peritoneal Carcinomatosis.

Epithelial ovarian cancer (EOC) is often asymptomatic and presents clinically in an advanced stage as widespread peritoneal microscopic disease that is generally considered to be surgically incurable. Targeted α-therapy with the α-particle-emitting radionuclide 225Ac (half-life, 9.92 d) is a high-linear-energy-transfer treatment approach effective for small-volume disease and even single cells. Here, we report the use of human epidermal growth factor receptor 2 (HER2) 225Ac-pretargeted radioimmunotherapy (PRIT) to treat a mouse model of human EOC SKOV3 xenografts growing as peritoneal carcinomatosis (PC). Methods: On day 0, 105 SKOV3 cells transduced with a luciferase reporter gene were implanted intraperitoneally in nude mice, and tumor engraftment was verified by bioluminescent imaging (BLI). On day 15, treatment was started using 1 or 2 cycles of 3-step anti-HER2 225Ac-PRIT (37 kBq/cycle as 225Ac-Proteus DOTA), separated by a 1-wk interval. Efficacy and toxicity were monitored for up to 154 d. Results: Untreated PC-tumor-bearing nude mice showed a median survival of 112 d. We used 2 independent measures of response to evaluate the efficacy of 225Ac-PRIT. First, a greater proportion of the treated mice (9/10 1-cycle and 8/10 2-cycle; total, 17/20; 85%) survived long-term compared with controls (9/27, 33%), and significantly prolonged survival was documented (log-rank [Mantel-Cox] P = 0.0042). Second, using BLI, a significant difference in the integrated BLI signal area to 98 d was noted between controls and treated groups (P = 0.0354). Of a total of 8 mice from the 2-cycle treatment group (74 kBq total) that were evaluated by necropsy, kidney radiotoxicity was mild and did not manifest itself clinically (normal serum blood urea nitrogen and creatinine). Dosimetry estimates (relative biological effectiveness-weighted dose, where relative biological effectiveness = 5) per 37 kBq administered for tumors and kidneys were 56.9 and 16.1 Gy, respectively. One-cycle and 2-cycle treatments were equally effective. With immunohistology, mild tubular changes attributable to α-toxicity were observed in both therapeutic groups. Conclusion: Treatment of EOC PC-tumor-bearing mice with anti-HER2 225Ac-PRIT resulted in histologic cures and prolonged survival with minimal toxicity. Targeted α-therapy using the anti-HER2 225Ac-PRIT system is a potential treatment for otherwise incurable EOC.

In vitro chemo-preventive efficacy of synthetic progestin Norethindrone in human epithelial ovarian cancer.

Progestin-only based oral contraceptives are majorly used as 'minipill' to prevent unintended pregnancy and treat conditions like polycystic ovary syndrome, hirsutism, and acne. However, the dearth of literature has constrained our comprehension of the exogenous progestin in relation to ovarian cancer progression. Therefore, the aim of the present study was to evaluate the chemo-preventive potential of synthetic progestin Norethindrone (NET) in epithelial ovarian cancer in vitro. Briefly, SKOV3 cells were treated with 1, 10 and 100µM concentrations of NET for seven days period. The assays for cell viability, wound-healing, cell cycle progression, detection of reactive oxygen species (ROS) and apoptosis were executed to illustrate the protective role of NET. To further clarify the underlying process, quantitative analysis of mRNA levels of oncogenes linked to angiogenesis, inflammation, proliferation, and metastasis (VEGF, HIF-1α, COX-2, and PGRMC1) and tumour suppressor (TP53) genes was conducted. Our study revealed that NET treatment significantly reduced SKOV3 cell growth by inducing cell cycle arrest at G2/M phase, elevating ROS levels, triggering cell death via apoptosis and necrosis, and inhibiting cell migration in a dose-dependent manner. Notably, NET also upregulated TP53 expression while concurrently downregulating VEGF, HIF-1α, COX-2, and PGRMC1 expression. Our results demonstrated that the chemo-preventive effect of Norethindrone may originate from the interaction of genes which exert a protective effect against ovarian carcinogenesis. The current findings also support further investigation, which may lead to changes in prescription practices or health-related advice for women.

Systematic high-throughput combination drug screen to enhance poly (ADP-ribose) polymerase (PARP) inhibitor efficacy in ovarian cancer.

5546 Background: PARP inhibitors currently offer the greatest benefit to patients with loss-of-function BRCA1 or 2 mutations or other causes of homologous recombination deficiency (HRD). We hypothesized that combination therapy, possibly by augmenting or inducing an HRD phenotype, would enhance the efficacy of PARP inhibition in epithelial ovarian cancer. Methods: We performed a high-throughput screen of an informer set containing FDA-approved drugs, clinical candidates, and small-molecule probes to identify synergistic partners with olaparib in representative HRD and non-HRD human epithelial ovarian cancer cells. Single agent activity was described by area under the curve of the Hafner growth rate index (AUC_GRI) and synergy was ranked by cumulative difference from Bliss (ΔBliss). Analysis of the drug screen was performed using algorithms developed by the Gulf Coast Consortia’s Combinatorial Drug Discovery Program at the Texas A&M Institute of Bioscience and Technology. MTT assays were then independently performed to verify and characterize synergy between CT7439, an agent selected following the drug screen, and olaparib. MTT data were analyzed using the SynergyFinder Plus web application. Results: In an initial single agent screen, we identified 62 compounds with a mean AUC_GRI <0.75, indicating inhibitory activity. Prioritizing more potent agents and those of mechanistic interest, we selected 40 hits to validate and advance to a combination screen. Diverse mechanisms of action were represented among the hits, including many small molecule inhibitors of various cell cycle pathways. Following a combination screen with olaparib, the compounds selected for final validation were: AZD 7762 (CHK1/2 inhibitor), dinaciclib (pan-CDK inhibitor), onalespib (HSP90 inhibitor), and SN-38 (topoisomerase 1 inhibitor). The ΔBliss for these agents are presented in the table. Due to mechanistic rationale and concern for overlapping toxicities among the other candidates, we focused further study on CDK inhibitors. In MTT assays, we identified robust synergy between olaparib and CT7439, a next-generation oral CDK12/13 inhibitor, with a mean Bliss synergy score of 1.31 and scores as high as 22.03 at certain concentrations in the non-HRD model OVCAR-5. These findings were recapitulated in the HRD cell lines OVCAR-4 (mean Bliss synergy score 1.56) and OVCAR-8 (mean Bliss synergy score 5.69). Results from an in vivo model will be presented as well. Conclusions: Pairing a PARP inhibitor and CDK inhibitor, a strategy identified by a high-throughput drug screen and known to impair homologous recombination, resulted in robust synergy in both HRD and non-HRD ovarian cancer models. Clinical translation of this combination may enhance the efficacy of PARP inhibitors in patients with ovarian cancer. [Table: see text]

The inhibitory receptors PD1, Tim3, and A2aR are highly expressed during mesoCAR T cell manufacturing in advanced human epithelial ovarian cancer

BackgroundChemotherapy and surgery have been the mainstays of epithelial ovarian cancer (EOC) treatment so far. Cellular immunotherapies such as CAR T cell therapy have recently given hope of a cure for solid tumors like EOC. However, extrinsic factors associated with the CAR T cell manufacturing process and/or intrinsic dysregulation of patient-derived T cells, which could be associated with cancer itself, cancer stage, and treatment regimen, may hamper the efficacy of CAR T cell therapy and promote their exhaustion or dysfunction.MethodsTo investigate the association of these factors with CAR T cell exhaustion, the frequency of T and CAR T cells expressing three immune inhibitory receptors (i.e., TIM3, PD1, A2aR) generated from T cells of EOC patients and healthy controls was measured during each stage of CAR T cell production.ResultsOur findings revealed that primary T cells from EOC patients show significantly elevated expression of immune inhibitory receptors, and this increase was more prominent in patients undergoing chemotherapy and those with advanced cancer. In addition, the CAR T cell manufacturing process itself was found to upregulate the expression of these inhibitory receptors and more importantly increase the population of exhausted mesoCAR T cells.ConclusionsOur observations suggest that intrinsic characteristics of patient-derived T cells and extrinsic factors in CAR T cell production protocols should be considered and properly counteracted during CAR T cell manufacturing process. In addition, mitigating the signaling of immune inhibitory receptors through pharmacological/genetic perturbation during CAR T cell manufacturing might profoundly improve CAR T cells function and their antitumor activity in EOC and other solid tumors.

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.

Tunicamycin induced inhibition of calpain 1 and 2 enzyme activity in ovarian cancer cells

Background: Tunicamycin (TN) is an antitumor agent and induced intracellular calcium levels in many cells, however its molecular mechanism is still needed to be explored. Calpeptin (Calp) is an inhibitor of both calpain 1 and 2 (CAPN-1/2) enzymes, and plays a fundamental role in tumor mechanism. In this study, the effects of TN and Calp were investigated on CAPN-1/2 enzyme activity in normal and ovarian cancer cells adhered to fibronectin. Methods: 24uM TN, 50uM Calp, and combined TN and Calp (TN+Calp) were applied for 1 and 12 hours to FN-bound (FN+) and non-FN-bound (FN-) normal human ovarian epithelial (IHOSE) and ovarian cancer (SKOV-3) cells. The activation of CAPN-1/2 was measured by the luminescent method and the significance of the results was analyzed with the t-test. Results: CAPN-1/2 enzyme activity (at 12 hour) was present in both cell lines, but the level of enzyme is higher in IHOSE cells compared to SKOV-3 cells. The results showed that 1 hour TN and TN+Calp applications stimulated CAPN-1/2 enzyme activity in IHOSE cells but did not show any stimulating effect in SKOV-3 cells. After 12-hour of treatment, the cells with TN, Calp or TN+Calp showed an inhibitory effect on CAPN-1/2 enzyme in both FN+IHOSE and SKOV-3 cells. At 12-hour TN+Calp administration was determined to be the most effective inhibitor in FN+ SKOV-3 since it inhibited CAPN1/2 activity statistically significantly more than both Calp and TN administrations. Conclusions: The effects of TN, Calp and TN+Calp applications on the CAPN-1/2 enzyme varied according to the cell type, normal or cancer cells, and whether the cell was bound to FN and the incubation period. 12 h administrations of TN, Calp or TN+Calp inhibited the CAPN-1/2 enzyme in both FN+ IHOSE and SKOV-3 cells.

Promoting action of long non-coding RNA small nucleolar RNA host gene 4 in ovarian cancer.

Long non-coding RNA (LncRNA) small nucleolar RNA host gene 4 (SNHG4) has been shown to be aberrantly expressed in a variety of cancers and involved in cancer development, but its role in ovarian cancer (OC) is unclear. The purpose of this study was to explore the biological function of SNHG4 in OC and reveal its potential downstream molecular targets. OC tumor tissue and normal tissue were collected; normal human ovarian epithelial cell line (IOSE80) and human ovarian cancer cell line (A2780, SKOV-3, OV-90 and CAOV3) were selected. RT-qPCR was used to detect SNHG4, miR-98-5p, and TMED5, while western blot was used to detect the protein expression levels of TMED5, Ki67, MMP-9, Bcl-2, Bax, Gsk3β, Wnt3a, and β-catenin. The subcellular localization of SNHG4 was assessed by nucleocytoplasmic separation assay. CCK-8, colony formation assay, flow cytometry, and Transwell were used to assess the biological behavior of OC cells. The targeting relationship between SNHG4, miR-98-5p and TMED5 was verified by dual luciferase reporter assay and RIP assay. In OC, SNHG4 and TMED5 were highly expressed, and miR-98-5p was underexpressed. Knockdown of SNHG4 inhibited OC cell proliferation, migration and invasion, promoted apoptosis, and prevented Wnt/β-catenin pathway activation. The effect of knockdown of SNHG4 was reversed by knockdown of miR-98-5p or overexpression of TMED5. Mechanistically, SNHG4 competitively adsorbed miR-98-5p to mediate TMED5 expression, thereby activating the Wnt/β-catenin pathway. SNHG4 accelerates OC development via mediating the miR-98-5p/TMED5 axis and activating the Wnt/β-Catenin pathway. SNHG4 gene silencing might be a novel option for OC treatment.

Indoxyl Sulfate Promotes Metastatic Characteristics of Ovarian Cancer Cells via Aryl Hydrocarbon Receptor–Mediated Downregulation of the Mas Receptor

Although platinum-combination chemotherapy shows a high response rate at the primary site, epithelial ovarian cancer (EOC) treatment remains challenging because of tumor recurrence and metastasis. Recent studies have revealed that chemotherapy paradoxically promotes cancer cell survival, proliferation, and metastasis, although the reason for this remains unclear. The underlying molecular mechanisms that contribute to chemotherapy-induced metastasis need to be elucidated to establish effective therapeutic strategies. Acute kidney injury is a known side effect of cisplatin treatment, and kidney dysfunction results in the accumulation of uremic toxins in the serum. The present study aimed to investigate whether indoxyl sulfate (IS), a representative uremic toxin, affects the pathophysiology of EOC. In this study, IS reduced the expression of Mas receptor (MasR) in cultured human EOC cells. Both knockdown of the aryl hydrocarbon receptor (AhR), which is an intracellular IS receptor, and inhibition of AhR function suppressed IS-mediated downregulation of MasR in SK-OV-3 cells. IS induced the phosphorylation of signal transducer and activator of transcription 3 (STAT3) in an AhR-dependent manner. Inhibition of the STAT3 pathway or reactive oxygen species production suppressed the IS-mediated reduction of MasR. IS stimulated cell migration and invasion of SK-OV-3 cells in an AhR-dependent manner. Cisplatin-nephropathy model mice exhibited elevated levels of serum IS accompanied by elevated levels of blood urea nitrogen and serum creatinine. Furthermore, intraperitoneal administration of IS in mice promoted tumor growth and metastasis. Finally, we found that the MasR agonist Ang-(1-7) suppressed the IS-mediated effects on cell proliferation, migration, and invasion of SK-OV-3 cells. However, the knockdown of MasR expression by specific small interfering RNA in the absence of IS resulted in only minimal promotion of cell migration and invasion. These findings demonstrate that IS promotes malignancy in ovarian cancer via AhR-mediated downregulation of MasR function, whereas Ang-(1-7) attenuates this effect, thereby suggesting that Ang-(1-7) could provide a future treatment strategy for this cancer type.

Drug repositioning of disulfiram induces endometrioid epithelial ovarian cancer cell death via the both apoptosis and cuproptosis pathways.

Various therapeutic strategies have been developed to overcome ovarian cancer. However, the prognoses resulting from these strategies are still unclear. In the present work, we screened 54 small molecule compounds approved by the FDA to identify novel agents that could inhibit the viability of human epithelial ovarian cancer cells. Among these, we identified disulfiram (DSF), an old alcohol-abuse drug, as a potential inducer of cell death in ovarian cancer. Mechanistically, DSF treatment significantly reduced the expression of the anti-apoptosis marker B-cell lymphoma/leukemia-2 (Bcl-2) and increase the expression of the apoptotic molecules Bcl2 associated X (Bax) and cleaved caspase-3 to promote human epithelial ovarian cancer cell apoptosis. Furthermore, DSF is a newly identified effective copper ionophore, thus the combination of DSF and copper was used to reduce ovarian cancer viability than DSF single treatment. Combination treatment with DSF and copper also led to the reduced expression of ferredoxin 1 and loss of Fe-S cluster proteins (biomarkers of cuproptosis). In vivo, DSF and copper gluconate significantly decreased the tumor volume and increased the survival rate in a murine ovarian cancer xenograft model. Thus, the role of DSF revealed its potential for used as a viable therapeutic agent for the ovarian cancer.

Cholesterol Biosynthesis Inhibitor RO 48-8071 Suppresses Growth of Epithelial Ovarian Cancer Cells in Vitro and In Vivo.

Epithelial Ovarian Cancer (EOC) cells express enzymes in the cholesterol biosynthetic pathway, making this pathway an attractive therapeutic target for controlling ovarian cancer. Potent small molecule inhibitors of one biosynthetic enzyme, Oxidosqualene Cyclase (OSC), have been identified, and RO 48-8071 (4'-[6-(allylmethylamino)hexyloxy]-4-bromo-2'-fluorobenzophenone fumarate) (RO), has emerged as a useful chemotherapeutic agent for breast and prostate cancer. Cell viability assays were performed to determine effects of RO 48-8071 on growth of EOC cells. Aldehyde Dehydrogenase (ALDH) assay was conducted to determine the effects of drug on reducing stem cell like properties of EOC cells. Finally, xenograft studies were performed to assess the ability of RO 48-8071 to inhibit the growth of EOC cells in vivo. We found that short-term (24-48 h) administration of pharmacological doses of RO effectively reduced the viability of drug-resistant EOC cells (SK-OV-3 and OVCAR-3), as determined with sulforhodamine B colorimetric assays. In 7-day assays, nanomolar concentrations of RO effectively inhibited the growth of EOC cells. RO also suppressed ALDH activity, a marker of stem cells. Importantly, RO significantly suppressed growth of xenografts derived from EOC cells when given to mice intraperitoneally (20-40 mg kg-1 day-1) for 27 days once tumors reached 100 mm3 (controls: 336 + 60 mm3; treated: 171 + 20 mm3) with no toxicity to the experimental animals. Mechanistically, RO induced apoptosis in tumor cells in vivo as shown with immunohistochemistry. Cholesterol biosynthesis inhibitor RO 48-8071 is thus a novel and potent inhibitor of human EOC, including EOC stem cells.

Cytotoxic Properties of C17 Polyacetylenes from the Fresh Roots of Panax ginseng on Human Epithelial Ovarian Cancer Cells.

Although C17 polyacetylenes from Panax ginseng exhibit cytotoxic properties against various tumor cells, there have been few experiments on epithelial ovarian carcinoma cells. This study aimed to investigate the cytotoxic effects of C17 polyacetylenes from P. ginseng against ovarian cancer cell lines. Four unreported (1–4) and fifteen known (5–19) C17 polyacetylenes were obtained from the roots of P. ginseng using repeated chromatography (open column, MPLC, and preparative HPLC). The chemical structures of all the compounds were determined by analyzing their spectroscopic data (NMR, IR, and optical rotation) and HR-MS. The structures of new polyacetylenes were elucidated as (3S,8S,9R,10R)-(-)-heptadeca-9,10-epoxy-4,6-diyne-3,8-diyl diacetate (1), (3S,8S,9R,10R)-(−)-heptadeca-1-en-9,10-epoxy-4,6-diyne-3,8-diyl diacetate (2), (−)-haptadeca-9,10-epoxy-8-methoxy-4,6-diyne-3,11-diol (3), and (3R,9R,10R)-(+)-3-acetoxy-9,10-dihydroxyheptadeca-1-en-4,6-diyne (4), named ginsenoynes O, P, and Q, and 3-acetyl panaxytriol, respectively. Subsequently, in vitro experiments on A2780 and SKOV3 human epithelial ovarian carcinoma cells were performed to assess the cytotoxic properties of the isolates. Among the isolates, panaquinquecol 4 (15) exhibited the most remarkable cytotoxic effects on both human ovarian cancer cells A2780 (IC50 value of 7.60 μM) and SKOV3 (IC50 value of 27.53 μM). Therefore, C17 polyacetylenes derived from P. ginseng may warrant further investigation for their therapeutic potential in epithelial ovarian cancer.

Retracted] Tumor suppressor role of miR-217 in human epithelial ovarian cancer by targeting IGF1R.

Following the publication of the above paper, a concerned reader drew to the Editors' attention that certain of the western blot data shown in Figs.4B and 6D, and the scratch‑wound assay data shown in Fig.2D, were strikingly similar to data that had already appeared in previously published papers written by different authors at different institutes. Furthermore, there appeared to be anomalies associated with the cell invasion assay data portrayed in Fig.2E. Having considered the issues identified, the Editor of Oncology Reports has decided that this article should be retracted from the Journal on account of the reappearance of previously published data and the uncertainties regarding the data in Fig.2E. After consulting the authors, they agreed with the Editor's decision that this paper should be retracted. The Editor apologizes to the readership for any inconvenience caused. [Oncology Reports 35: 1671‑1679, 2016; DOI: 10.3892/or.2015.4498].