Human Epithelial Ovarian Cancer Research Articles

NLRP3 Inflammasome Upregulates PD-L1 in Ovarian Cancer and Contributes to an Immunosuppressive Microenvironment.

The NLRP3 inflammasome has been implicated in the initiation of inflammation and tumorigenesis; however, its role in epithelial ovarian cancer (EOC) remains unclear. This study employed high-throughput sequencing data, ELISA, clone formation assay, Western blot, and flow cytometric analysis to investigate the specific role of the NLRP3 inflammasome in EOC. NLRP3 was highly expressed in human EOC tissues and correlated with an unfavorable prognosis. Activation of the NLRP3 inflammasome by LPS and ATP promoted EOC cell proliferation and increased IL-1 and PD-L1 levels. MCC950, a NLRP3 inflammasome blocker, reduced IL-1 and PD-L1 levels and diminished tumor-immune suppressive cells, such as myeloid-derived suppressor cells (MDSCs), tumor-associated macrophages (TAMs), and PD-1+ CD4+ T cells, in a murine model of ovarian cancer. This intervention also suppressed tumor growth. Our investigation revealed the pro-tumorigenic role of the NLRP3 inflammasome and its regulation of PD-L1 expression in EOC. Blockade of the NLRP3 inflammasome led to reduced PD-L1 expression, fewer immunosuppressive cells, and suppressed tumor growth. These findings suggest that targeting the NLRP3 inflammasome-PD-L1 axis could be a novel treatment approach for ovarian cancer.

Sparstolonin B Reduces Estrogen-Dependent Proliferation in Cancer Cells: Possible Role of Ceramide and PI3K/AKT/mTOR Inhibition.

Background: The aim of this study was to determine the effect of Sparstolonin B (SsnB) on cell proliferation and apoptosis in human breast cancer (MCF-7) and human ovarian epithelial cancer (OVCAR-3) cell lines in the presence and absence of estradiol hemihydrate (ES). Phosphoinositol-3 kinase (PI3K), phosphorylated protein kinase B alpha (p-AKT), phosphorylated mTOR (mechanistic target of rapamycin) signaling proteins, and sphingomyelin/ceramide metabolites were also measured within the scope of the study. Methods: The anti-proliferative effects of SsnB therapy were evaluated over a range of times and concentrations. Cell proliferation was determined by measuring the Proliferating Cell Nuclear Antigen (PCNA). PCNA was quantified by ELISA and cell distribution was assessed by immunofluorescence microscopy. MTT analysis was used to test the vitality of the cells, while LC-MS/MS was used to analyze the amounts of ceramides (CERs), sphingosine-1-phosphate (S1P), and sphingomyelins (SMs). TUNEL labeling was used to assess apoptosis, while immunofluorescence staining and enzyme-linked immunosorbent assay (ELISA) were used to measure the levels of PI3K, p-AKT, and p-mTOR proteins. Results: Sparstolonin B administration significantly decreased cell viability in MCF-7 and OVCAR-3 cells both in the presence and absence of ES, while it did not cause toxicity in healthy human fibroblasts. In comparison to controls, cancer cells treated with SsnB showed a significant drop in the levels of S1P, PI3K, p-AKT, and p-mTOR. In cancer cells cultured with SsnB, a significant increase in intracellular concentrations of C16-C24 CERs and apoptosis was observed. Conclusions: SsnB downregulated the levels of S1P, PI3K, p-AKT, and p-mTOR while reducing cell proliferation and promoting ceramide buildup and apoptosis.

LKB1 and STRADα Promote Epithelial Ovarian Cancer Spheroid Cell Invasion.

Late-stage epithelial ovarian cancer (EOC) involves the widespread dissemination of malignant disease throughout the peritoneal cavity, often accompanied by ascites. EOC metastasis relies on the formation of multicellular aggregates, called spheroids. Given that Liver Kinase B1 (LKB1) is required for EOC spheroid viability and LKB1 loss in EOC cells decreases tumor burden in mice, we investigated whether the LKB1 complex controls the invasive properties of human EOC spheroids. LKB1 signalling was antagonized through the CRISPR/Cas9 genetic knockout of LKB1 and/or the RNAi-dependent targeting of STE20-related kinase adaptor protein (STRAD, an LKB1 activator). EOC spheroids expressing nuclear GFP (green) or mKate2 (red) constructs were embedded in Matrigel for real-time live-cell invasion monitoring. Migration and invasion were also assessed in spheroid culture using Transwell chambers, spheroid reattachment, and mesothelial clearance assays. The loss of LKB1 and STRAD signalling decreased cell invasion through Matrigel and Transwell membranes, as well as mesothelial cell clearance. In the absence of LKB1, zymographic assays identified a loss of matrix metalloproteinase (MMP) activity, whereas spheroid reattachment assays found that coating plates with fibronectin restored their invasive potential. A three-dimensional EOC organoid model demonstrated that organoid area was greatly reduced by LKB1 loss. Overall, our data indicated that LKB1 and STRAD facilitated EOC metastasis by promoting MMP activity and fibronectin expression. Given that LKB1 and STRAD are crucial for EOC metastasis, targeting LKB1 and/or STRAD could disrupt the dissemination of EOC, making inhibitors of the LKB1 pathway an alternative therapeutic strategy for EOC patients.

AmphiregulinDownregulates E-cadherin Expressionby Activating YAP/Egr-1/Slug Signaling in SKOV3 Human Ovarian Cancer Cells.

Amphiregulin (AREG) stimulates human epithelial ovarian cancer (EOC) cell invasion by downregulating E-cadherin expression. YAP is a transcriptional cofactor that has been shown to regulate tumorigenesis. This study aimed to examine whether AREG activates YAP in EOC cells and explore the roles of YAP in AREG-induced downregulation of E-cadherin and cell invasion. Analysis of the Cancer Genome Atlas (TCGA) showed that upregulation of AREG and EGFR were associated with poor survival in human EOC. Treatment of SKOV3 human EOC cells with AREG induced the activation of YAP. In addition, AREG downregulated E-cadherin, upregulated Egr-1 and Slug, and stimulated cell invasion. Using gain- and loss-of-function approaches, we showed that YAP was required for the AREG-upregulated Egr-1 and Slug expression. Furthermore, YAP was also involved in AREG-induced downregulation of E-cadherin and cell invasion. This study provides evidence that AREG stimulates human EOC cell invasion by downregulating E-cadherin expression through the YAP/Egr-1/Slug signaling.

THUMPD3-AS1 inhibits ovarian cancer cell apoptosis through the miR-320d/ARF1 axis.

Ovarian cancer is one of the most common gynecologic malignancies that has a poor prognosis. THUMPD3-AS1 is an oncogenic long noncoding RNA (lncRNA) in several cancers. Moreover, miR-320d is downregulated and inhibited proliferation in ovarian cancer cells, whereas ARF1 was upregulated and promoted the malignant progression in epithelial ovarian cancer. Nevertheless, the role of THUMPD3-AS1 in ovarian cancer and the underlying mechanism has yet to be elucidated. Human normal ovarian epithelial cells (IOSE80) and ovarian cancer cell lines (CAVO3, A2780, SKOV3, OVCAR3, and HEY) were adopted for invitro experiments. The functional roles of THUMPD3-AS1 in cell viability and apoptosis were determined using CCK-8, flow cytometry, and TUNEL assays. Western blot was performed to assess the protein levels of ARF1, Bax, Bcl-2, and caspase 3, whereas RT-qPCR was applied to measure ARF1 mRNA, THUMPD3-AS1, and miR-320d levels. The targeting relationship between miR-320d and THUMPD3-AS1 or ARF1 was validated with dual luciferase assay. THUMPD3-AS1 and ARF1 were highly expressed in ovarian cancer cells, whereas miR-320d level was lowly expressed. THUMPD3-AS1 knockdown was able to repress cell viability and accelerate apoptosis of OVCAR3 and SKOV3 cells. Also, THUMPD3-AS1 acted as a sponge of miR-320d, preventing the degradation of ARF1. MiR-320d downregulation reversed the tumor suppressive function induced by THUMPD3-AS1 depletion. Additionally, miR-320d overexpression inhibited ovarian cancer cell viability and accelerated apoptosis, which was overturned by overexpression of ARF1. THUMPD3-AS1 inhibited ovarian cancer cell apoptosis by modulation of miR-320d/ARF1 axis. The discoveries might provide a prospective target for ovarian cancer treatment.

LncRNA HOXA‑AS2 promotes the progression of epithelial ovarian cancer via the regulation of miR‑372.

Long non-coding RNAs, such as homeobox A cluster antisense RNA2 (HOXA-AS2) are understood to be involved in tumor growth and development of numerous cancers. However, the role of HOXA-AS2 in the progression of human epithelial ovarian cancer (EOC) remains unclear. In the present study, the expression of HOXA-AS2 was found to be upregulated in EOC tissues compared with noncancerous tissues, and to be strongly correlated to an advanced Federation International of Gynecology and Obstetrics grade and poor prognosis. Knockdown of HOXA-AS2 in the EOC cells inhibited cell proliferation, invasion and migration, as well as inducing cell apoptosis. The ENCORI database was used to screen the microRNAs (miRNAs/miRs) that bound to HOXA-AS2, and one was tested using RNA pull-down and luciferase reporter assays. It was demonstrated that HOXA-AS2 functioned through the competing endogenous RNA mechanism to regulate miR-372. It was also demonstrated that the downregulation of miR-372 reversed the inhibitory effects of the knockdown of HOXA-AS2 in EOC cells. These results indicated that HOXA-AS2 promoted EOC progression by regulating the miR-372, which suggests that HOXA-AS2 may be a therapy target for EOC.

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.

MPP7 mediates EMT via Wnt/β-catenin pathway to promote polarity changes in epithelial ovarian cancer cells.

Ovarian cancer is one of the gynecological malignancies with the highest mortality rate. Its widespread metastasis is difficult to cure, and the beneficiaries of targeted therapy are still limited, which has been a long-standing bottleneck problem. MAGUK P55 scaffold protein 7 (MPP7) plays an important role in the establishment of epithelial cell polarity, but its potential significance in epithelial ovarian cancer is still unclear. In this study, we investigated the expression profile of MPP7 and its functional role in epithelial ovarian cancer. Through analysis of TCGA and GEO databases, combined with immunohistochemical staining of ovarian tumor tissue chips, it was found that MPP7 is significantly overexpressed in epithelial ovarian cancer tissue, and its high expression is closely related to poor prognosis of patients. It has been verified through cell function experiments that interference with MPP7 can inhibit the proliferation, migration, and invasion of ovarian cancer cells in vitro. Performing planar polarity immunofluorescence staining on ovarian cancer cells revealed that interference with MPP7 can cause polarity changes in ovarian cancer cells. The transcriptome sequencing results of the ovarian cancer database were analyzed, and Western Blot was used to verify that MPP7 may mediate EMT via Wnt/β-catenin signaling pathway and promote changes in cell polarity in human epithelial ovarian cancer, thereby promoting cancer progression, demonstrating the potential of MPP7 as a new biomarker and target for the diagnosis and treatment of ovarian cancer.

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.