Role In Ovarian Cancer Progression Research Articles

Unraveling the role of tissue colonized microbiome in ovarian cancer progression

BackgroundOvarian cancer (OC) is found to be the third most common gynecologic malignancy over the world, having the highest mortality rate among such tumors. Emerging studies underscore the presence of microorganisms within tumor tissues, with certain pathogens intricately linked to disease onset and progression. Disruption of the microbiome frequently precipitates disturbances in host metabolic and immune pathways, thereby fostering the development of cancer. MethodsIn this study, we initiated the investigation by conducting microbial reannotation on the RNA sequencing data derived from ovarian cancer tissues. Subsequently, a comprehensive array of analyses on tissue microbes was executed. These analyses encompassed the assessment of intergroup variations in microbial diversity, differential microbiological analysis, exploration of the association between host gene expression and microbial abundance, as well as an enrichment analysis of functional pathways linked to host genes associated with microbes. ResultsThe analysis results revealed that Proteobacteria, Actinobacteria, Firmicutes, and Bacteroidetes were the main components at phylum level in ovarian tissue. Notably, the microbial composition of ovarian cancer tissue significantly diverged from that of normal ovarian tissue e, exhibiting markedly lower alpha diversity and distinct beta diversity. Besides, pathogenic microorganisms Achromobacter xylosoxidans and Enterobacter hormaechei were enriched in cancer tissue. Host genes associated with these pathogens were enriched in key pathways including “JAK-STAT signaling pathway”, “Transcriptional misregulation in cancer”, and “Th1 and Th2 cell differentiation”, suggesting their role in ovarian cancer progression through microbial dysbiosis and immune response interaction. ConclusionAbundance of pathogenic microorganisms in ovarian cancer tissue could modulate the expression of host genes, consequently impacting cancer-related signaling pathways and fostering cancer progression.

Integration of single-cell RNA-seq and bulk RNA-seq data to construct and validate a cancer-associated fibroblast-related prognostic signature for patients with ovarian cancer

BackgroundTo establish a prognostic risk profile for ovarian cancer (OC) patients based on cancer-associated fibroblasts (CAFs) and gain a comprehensive understanding of their role in OC progression, prognosis, and therapeutic efficacy.MethodsData on OC single-cell RNA sequencing (scRNA-seq) and total RNA-seq were collected from the GEO and TCGA databases. Seurat R program was used to analyze scRNA-seq data and identify CAFs clusters corresponding to CAFs markers. Differential expression analysis was performed on the TCGA dataset to identify prognostic genes. A CAF-associated risk signature was designed using Lasso regression and combined with clinicopathological variables to develop a nomogram. Functional enrichment and the immune landscape were also analyzed.ResultsFive CAFs clusters were identified in OC using scRNA-seq data, and 2 were significantly associated with OC prognosis. Seven genes were selected to develop a CAF-based risk signature, primarily associated with 28 pathways. The signature was a key independent predictor of OC prognosis and relevant in predicting the results of immunotherapy interventions. A novel nomogram combining CAF-based risk and disease stage was developed to predict OC prognosis.ConclusionThe study highlights the importance of CAFs in OC progression and suggests potential for innovative treatment strategies. A CAF-based risk signature provides a highly accurate prediction of the prognosis of OC patients, and the developed nomogram shows promising results in predicting the OC prognosis.

Abstract 5998: Pharmacological inhibition of the LIF-LIFR autocrine loop reveals vulnerability of ovarian cancer to ferroptosis

Abstract Introduction: Of all gynecologic cancers, epithelial ovarian cancer (OCa) stands out with the highest mortality rates. Despite all efforts, 90% of individuals who receive standard surgical and cytotoxic therapy experience disease recurrence. The potential involvement of leukemia inhibitory factor (LIF) and its receptor (LIFR) in the progression of OCa is still obscure. In this study, we examined the mechanisms by which disruption of LIF/LIFR autocrine loops contributes to the cell death of ovarian cancer cells. Methods: The expression profiles of LIF and LIFR were obtained using 24 distinct OCa model cells, comprising both primary and established cell lines. The effects of EC359 on OCa cells were evaluated using reporter assays, colony formation, cell death, and cell viability. Flow cytometry was utilized to analyze lipid peroxidation. The Agilent Seahorse XF Pro Analyzer was used to calculate the extracellular acidification rate (ECAR) and oxygen consumption rate (OCR). Furthermore, flow cytometry was used for the preparation and analysis of lymphocytes. Mechanistic investigations were performed with RT-qPCR and RNA-seq analysis. The efficacy of the LIFR inhibitor EC359 as a targeted therapy was investigated using cell-based xenografts, syngeneic xenografts, patient-derived organoids (PDO), and patient-derived xenograft (PDX) models. Results: Analysis of cancer databases revealed that elevated expression of LIF or LIFR was associated with poor progression-free survival of OCa patients and a predictor of poor response to chemotherapy. Using 24 different primary and established OCa cell lines that represent four subtypes of epithelial OCa, we demonstrated that LIF/LIFR autocrine signaling is active in OCa. Moreover, treatment with EC359, a novel LIFR inhibitor, significantly reduced OCa cell viability and cell survival with an IC50 ranging from 5 to 50 nM. Furthermore, EC359 diminished the stemness of OCa cells. Mechanistic studies using RNA-seq and rescue experiments unveiled that EC359 primarily induced ferroptosis by suppressing the glutathione antioxidant defense system. Using multiple in vitro, ex vivo, and in vivo models including organoids, cell-based xenografts, patient-derived explants, and xenograft tumors, we demonstrated that EC359 dramatically reduced the growth and progression of OCa. Additionally, EC359 therapy considerably improved tumor immunogenicity by robust CD45+ leukocyte tumor infiltration and polarizing tumor-associated macrophages (TAMs) toward M1 phenotype while showing no impact on normal T-, B-, and other immune cells. Conclusions: Collectively, our findings indicate that the LIF/LIFR autocrine loop plays an essential role in OCa progression and that EC359 could be a promising therapeutic agent for OCa. Citation Format: Behnam Ebrahimi, Suryavathi Viswanadhapalli, Uday P. Pratap, Rahul Gopalam, Xue Yang, Prabhakar P. Venkata, Viktor Drel, Bindu Santhamma, Swapna Konda, Xiaonan Li, Alondra L. Rodriguez Sanchez, Hui Yan, Gangadhara R. Sareddy, Zhenming Xu, Brij B. Singh, Philip T. Valente, Yidong Chen, Zhao Lai, Manjeet Rao, Edward R. Kost, Tyler Curiel, Rajeshwar R. Tekmal, Hareesh B. Nair, Ratna K. Vadlamudi. Pharmacological inhibition of the LIF-LIFR autocrine loop reveals vulnerability of ovarian cancer to ferroptosis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5998.

ISG15 mediates the function of extracellular vesicles in promoting ovarian cancer progression and metastasis

AbstractThe interferon stimulated gene 15 (ISG15), a ubiquitin like protein and its conjugates have been implicated in various human malignancies. However, its role in ovarian cancer progression and metastasis is largely unknown. In high grade serous ovarian cancer (HGSOC), ascites is the major contributor to peritoneal metastasis. In this study, we identified significantly elevated ISG15 protein expression in HGSOC patient ascites, ascites derived primary ovarian cancer cells (POCCs), POCC small extracellular vesicles (sEVs) as well as metastatic tissue. Our results demonstrates that ISG15 increases exocytosis in ascites‐derived POCCs by decreasing the endosome‐lysosomal fusion, indicating a key role in sEV secretion. Further, knockdown (KD) of ISG15 resulted in a significant decrease in vesicles secretion from HGSOC cells and in vivo mouse models, leading to reduced HGSOC cell migration and invasion. Furthermore, our pre‐clinical mouse model studies revealed the influence of vesicular ISG15 on disease progression and metastasis. In addition, knockdown of ISG15 or using the ISG15 inhibitor, DAP5, in combination therapy with carboplatin showed to improve the platinum sensitivity in‐vitro and reduce tumour burden in‐vivo. We also found that ISG15 expression within sEV represents a promising prognostic marker for HGSOC patients. Our findings suggest that ISG15 is a potential therapeutic target for inhibiting progression and metastasis in HGSOC and that vesicular ISG15 expression could be a promising biomarker in the clinical management of ovarian cancer.Significance: High‐grade serous ovarian cancer (HGSOC) has high morbidity and mortality rates, but its progression and metastasis are still poorly understood, and there is an urgent need for early detection and targeted therapies. Our study presents novel findings that implicate ISG15‐mediated vesicular proteins in the advancement and spread of HGSOC. These results offer pre‐clinical evidence of potential new molecular targets, prognostic markers and therapeutic strategies for HGSOC that could ultimately enhance patient survival.

Dysregulation of Peripheral Blood Mononuclear Cells and Immune-Related Proteins during the Early Post-Operative Immune Response in Ovarian Cancer Patients.

Surgical treatment is a cornerstone of ovarian cancer (OC) therapy and exerts a substantial influence on the immune system. Immune responses also play a pivotal and intricate role in OC progression. The aim of this study was to investigate the dynamics of immune-related protein expression and the activity of peripheral blood mononuclear cells (PBMCs) in OC patients, both before surgery and during the early postoperative phase. The study cohort comprised 23 OC patients and 20 non-cancer controls. A comprehensive analysis of PBMCs revealed significant pre-operative downregulation in the mRNA expression of multiple immune-related proteins, including interleukins, PD-1, PD-L1, and HO-1. This was followed by further dysregulation during the first 5 post-operative days. Although most serum interleukin concentrations showed only minor changes, a distinct increase in IL-6 and HO-1 levels was observed post-operatively. Reduced metabolic and phagocytic activity and increased production of reactive oxygen species (ROS) were observed on day 1 post-surgery. These findings suggest a shift towards immune tolerance during the early post-operative phase of OC, potentially creating a window for treatment. Further research into post-operative PBMC activity could lead to the development of new or improved treatment strategies for OC.

MicroRNAs Can Influence Ovarian Cancer Progression by Dysregulating Integrin Activity.

Ovarian cancer is a deadly disease that affects thousands of women worldwide. Integrins, transmembrane receptors that mediate cell adhesion and signaling, play important roles in ovarian cancer progression, metastasis, and drug resistance. Dysregulated expression of integrins is implicated in various cellular processes, such as cell migration, invasion, and proliferation. Emerging evidence suggests that microRNAs (miRNAs) can regulate integrin expression and function, thus affecting various physiological and pathological processes, including ovarian cancer. In this article, we review the current understanding of integrin-mediated cellular processes in ovarian cancer and the roles of miRNAs in regulating integrins. We also discuss the therapeutic potential of targeting miRNAs that regulate integrins for the treatment of ovarian cancer. Targeting miRNAs that regulate integrins or downstream signaling pathways of integrins may provide novel therapeutic strategies for inhibiting integrin-mediated ovarian cancer progression.

Abstract 4705: Profiling of immune cell components and soluble factors in ovarian cancer ascites highlights impaired immune environment

Abstract Background: It’s now increasingly recognized that ovarian cancer (OC) ascites play a significant role in OC progression - behavior of tumor cells is influenced by the nature of their surrounding microenvironment. Thus, characterization of ascites composition is essential to understand how this milieu affects tumor progression and particularly the immunosuppressive pathways that would underlie immune response dysfunctions and, in turn, how biological ascites effects can be influenced by that composition. Methods: Ascites samples were collected from advanced OC patients. Through respective multiplexed approaches of flow cytometry-based marker expression analysis and quantitation of mediators, immune context was profiled by investigating immune cell composition and levels of a plethora of soluble factors, including cytokines/chemokines, and metabolic pathways of some amino acids known to be involved in immunosuppression. Furthermore, ascites fluids were functionally screened for their biological effects on healthy monocytes, either undifferentiated or undergoing M1 polarization. Results: Unlike healthy PBMCs, OC ascites were mostly “enriched” in regulatory/immunosuppressive immune cell subsets including T and myeloid populations. Also, T cells were shown to highly express immune checkpoints such as PD1 in T cells and TIGIT in Tregs. Intriguingly, a high CD4/CD8 ratio was seen. Also, CD163+ tumor-associated macrophages were shown to express CSF1R, CCR8 and CCR2, and to even display a mixed phenotype since also expressing Arg1, CD80, and iNOS. On acellular fractions, most ascites demonstrated elevated CCL18, IL6, LIF, VEGF, and CCL2 levels, and low IL2, IL4, and IL17 levels. Interestingly, unlike healthy plasmas, these ascites appeared to harbor a metabolically-immunosuppressive profile characterized by high glutaminolysis and tryptophan (Trp) degradation in kynurenine (Kyn). Functionally, we demonstrated that not only ascites basically polarized monocytes into M2 macrophages, but even antagonized with their M1 polarization to ultimately tilt to M2 status. Conclusions: Taken together, our data show that ascites fluids most favorable to the M2 phenotype were associated with high LIF, VEGF, IL6, CCL2, and CCL18 levels, and with elevated Kyn to Trp ratios - Kyn levels being strongly higher than in healthy plasmas. Our results thus highlight a peculiar altered environment of OC ascites where a mixture of suppressive cells and signaling factors mediate extracellular cues leading to immune cell activity dysfunction. Altogether, these translational findings highlight OC ascites as a valuable tool to understand the mechanisms of suppression and develop predictive profiles, and to provide new insights for the identification of new targets and development of targeted-therapies. Citation Format: Assia Chaibi, Coriolan Lebreton, Dominique Bodet, Jean-Philippe Guegan, Guillaume Babin, Antoine Italiano, Alban Bessede, Imane Nafia. Profiling of immune cell components and soluble factors in ovarian cancer ascites highlights impaired immune environment. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4705.

Interleukine-10 in ovarian cancer.

Interleukins serve as communicating molecules between cells, mediating key interactions in the tumor microenvironment (TME) between immune cells and non-immune cells. Interleukin-10 (IL-10), a multifunctional cytokine with multiple properties, has been extensively studied in various aspects of immunology and cancer biology. IL-10 is pleiotropic, promotes cytotoxicity, yet inhibits antitumorresponses. In recent years, the role of IL-10 in ovarian cancer (OC) progression and treatment has gained significant scientific attention, elucidating the signaling pathways triggered by IL-10 action. OC, the leading cause of gynecologic cancer-related deaths, is characterized by ascites, which hosts an intricate TME that is not responsive to treatment by immune checkpoint inhibition. IL-10, known for its immunosuppressive and anti-inflammatory properties, plays a complex role in OC progression, immune modulation, and therapeutic response and has a potential therapeutic property as a target and as an effector. As the literature of basic science research studying the role of IL-10 in the TME of OC scopes a few decades and some data is contrasting, it is important to review the literature and provide concise input derived from it. This review aims to provide a comprehensive overview of the current understanding of IL-10 in OC, highlighting its influence on tumor growth, immune evasion, and potential as a therapeutic target.

Circular RNAs in Epithelial Ovarian Cancer: From Biomarkers to Therapeutic Targets.

Epithelial ovarian cancer (EOC) is the most lethal gynecological cancer, and more than 70% of patients are diagnosed at advanced stages. Despite the application of surgery and chemotherapy, the prognosis remains poor due to the high relapse rate. It is urgent to identify novel biomarkers and develop novel therapeutic strategies for EOC. Circular RNAs (circRNAs) are a class of noncoding RNAs generated from the "back-splicing" of precursor mRNA. CircRNAs exert their functions via several mechanisms, including acting as miRNA sponges, interacting with proteins, regulating transcription, and encoding functional proteins. Recent studies have identified many circRNAs that are dysregulated in EOC and may be used as diagnostic and prognostic markers. Increasing evidence has revealed that circRNAs play a critical role in ovarian cancer progression by regulating various cellular processes, including proliferation, apoptosis, metastasis, and chemosensitivity. The circRNA-based therapy may be a novel strategy that is worth exploring in the future. Here, we provide an overview of EOC and circRNA biogenesis and functions. We then discuss the dysregulations of circRNAs in EOC and the possibility of using them as diagnostic/prognostic markers. We also summarize the role of circRNAs in regulating ovarian cancer development and speculate their potential as therapeutic targets.

TARDBP promotes ovarian cancer progression by altering vascular endothelial growth factor splicing.

Disruptions in alternative splicing regulation play an essential role in ovarian cancer progression. However, the underlying mechanism remains unclear. TAR DNA-binding protein (TARDBP) plays a crucial role in alternative splicing regulation. Herein we found that TARDBP expression was significantly upregulated in OC tissue samples, particularly in cases of metastasis; further, TARDBP expression was markedly upregulated in OC patients with poor prognosis. These findings were validated by extensive tissue microarray data. TARDBP was also found to promote tumorigenesis and metastasis of OC cells in vitro and in vivo. Mechanistically, TARDBP increased the binding of the splicing factor serine/arginine-rich splicing factor 1 (SRSF1) to intron 7 of vascular endothelial growth factor (VEGF), increasing the formation of the proangiogenic VEGF165 isoform and decreasing that of the antiangiogenic VEGF165b isoform. The abnormal alternative splicing event was responsible for the activation of angiogenesis and contributed to the progression of OC. To conclude, TARDBP was found to regulate the alternative splicing of VEGF via SRSF1, induce the formation of VEGF165 but inhibit that of VEGF165b, and promote OC angiogenesis. Hence, TARDBP can serve as an independent prognostic factor and new target for OC cancer therapy.

Immune Tumor Microenvironment in Ovarian Cancer Ascites.

Ovarian cancer (OC) has a specific type of metastasis, via transcoelomic, and most of the patients are diagnosed at advanced stages with multiple tumors spread within the peritoneal cavity. The role of Malignant Ascites (MA) is to serve as a transporter of tumor cells from the primary location to the peritoneal wall or to the surface of the peritoneal organs. MA comprise cellular components with tumor and non-tumor cells and acellular components, creating a unique microenvironment capable of modifying the tumor behavior. These microenvironment factors influence tumor cell proliferation, progression, chemoresistance, and immune evasion, suggesting that MA play an active role in OC progression. Tumor cells induce a complex immune suppression that neutralizes antitumor immunity, leading to disease progression and treatment failure, provoking a tumor-promoting environment. In this review, we will focus on the High-Grade Serous Carcinoma (HGSC) microenvironment with special attention to the tumor microenvironment immunology.

Odd-skipped related 1 plays a tumor suppressor role in ovarian cancer via promoting follistatin-like protein 1 transcription.

Zinc-finger transcription factor odd-skipped related 1 (OSR1) is involved in the progression of certain types of cancers, via regulating the transcription of downstream genes. However, the function of OSR1 in ovarian cancer (OC) progression remains unclear. The present study aimed to explore the OSR1 expression pattern in OC tissues and cell lines. Functional assays were performed to explore the regulatory effects of OSR1 on OC cell growth, migration and invasion in vitro and in vivo. Results of the present study demonstrated that OSR1 was significantly downregulated in OC tissues compared with healthy ovarian tissues (P < 0.01). Moreover, SKOV-3 and OVCAR-3 cells with low OSR1 expression were used for functional studies, and results demonstrated that OSR1 overexpression suppressed cell growth by inhibiting cell cycle progression and inducing cell apoptosis in vitro. OC cells with higher OSR1 expression levels exhibited reduced levels of migration and invasion, when compared with the corresponding control. In addition, OSR1 expression in xenografts models resulted in diminished tumor volume and suppressed tumorigenesis. OSR1 enhanced follistatin-like protein 1 (FSTL1) expression at the transcriptional level through directly binding to the promoter of FSTL1, which was commonly reported to exert a tumor suppressor role in OC progression. Moreover, FSTL1 knockdown reversed the action of OSR1 overexpression in OC progression, including cell viability, migration, invasion, and apoptosis. In conclusion, these results indicated that OSR1 may function as a tumor suppressor through augmenting FSTL1 transcription in OC progression, suggesting that the OSR1/ FSTL1 axis may exhibit potential as a therapeutic target for OC therapy.

The effect of substance P and its specific antagonist (aprepitant) on the expression of MMP-2, MMP-9, VEGF, and VEGFR in ovarian cancer cells.

Substance P (SP) has a crucial role in cancer initiation and progression via binding to its specific receptor (NK1R). Various evidence confirmed the overexpression of NK1R and SP in the tissue of multiple cancers, including ovarian cancer. Despite numerous studies, the mechanism of the SP/NK1R system on migration and angiogenesis of ovarian cancer cells has not yet been deciphered. In this study, considering the critical factors in cell migration (MMP-2, MMP-9) and angiogenesis (VEGF, VEGFR), we investigated the possible mechanism of this system in inducing migration and angiogenesis of ovarian cancer cells. First, the resazurin assay was conducted to evaluate the cytotoxic effect of aprepitant (NK1R antagonist) on the viability of A2780 ovarian cancer cells. After that, the impact of this system and aprepitant on the mRNA expression of the factors mentioned above were studied using RT-PCR. Besides, the scratch assay was performed to confirm the effect of the SP/NK-1R system and aprepitant on cell migration. Our results implied that this system induced cell migration and angiogenesis by increasing the mRNA expression of MMP-2, MMP-9, VEGF, and VEGFR. The obtained results from the scratch assay also confirmed the positive effect of this system on cell migration. Meanwhile, the blocking of NK1R by aprepitant suppresses the SP effects on cell migration and angiogenesis. Overall, the SP/NK1R system plays a vital role in ovarian cancer progression, and the inhibition of NK1Rusing aprepitant could inhibit the spread of ovarian cancer cells through metastasis and angiogenesis.

Abstract 4066: Anticancer effects of the gold complex auranofin on high-grade serous ovarian cancer cells

Abstract High-grade serous ovarian cancer (HGSOC) is the 11th most common cancer-causing death in women. HGSOC is treated with platinum (Pt)-based chemotherapy, to which patients develop resistance over time, leaving them with very limited therapeutic options. Thus, new treatments are needed for these patients. In the present work, we provide evidence for the in vitro anti-HGSOC efficacy of the gold complex auranofin (AUF), a compound approved in the clinic in the 1980’s as an anti-rheumatic agent. AUF targets thioredoxin reductase 1 (TrxR1), which is overexpressed in many cancers, including ovarian cancer. Using the Kaplan-Meir plotter database we analyzed that high expression of TrxR1 predicted poor overall survival, suggesting that TrxR1 plays an important role in ovarian cancer progression. We show that AUF impairs the growth of HGSOC cells regardless of Pt sensitivity. HGSOC cells obtained from the same patient when it was clinically sensitive (PEO1) or resistant (PEO4) to Pt-based chemotherapy, were both equally sensitive to the growth inhibition induced by the gold complex in a concentration-dependent manner when using an MTT reduction assay. The toxicity of AUF against HGSOC cells was further studied exposing PEO1 cells to the compound and assessing cell number, cell viability, and cell cycle traverse. Results showed that AUF blocked cell proliferation, reduced viability, and caused accumulation of cells with hypo-diploid DNA content, suggesting a likely apoptosis-mediated cell death mechanism. We confirmed that AUF-triggered lethality was driven by apoptosis by measuring the accumulation of Annexin V positive/7-AAD negative cells via flow cytometry. We also found out that the lethality of AUF required the induction of oxidative stress because the effect was prevented by the presence of the reactive oxygen species (ROS) scavenger N-acetyl-cysteine. We further show that AUF-induced ROS production is associated with the generation of DNA damage as denoted by the increase in the phosphorylation of the Ser-139 residue of the histone variant H2AX by western blotting thus signaling a genotoxic endpoint. Finally, we generated evidence that the combination of AUF and the Pt agent cisplatin (CDDP) is more potent than either drug alone in inducing lethality in PEO4 cells isolated from a patient when Pt-resistant. In summary, we provide proof-of-principle that the TrxR1 inhibitor AUF impairs the survival capacity of HGSOC cells regardless of their Pt sensitivities, triggering a program of apoptosis induced by oxidative stress that is associated with DNA damage; such toxicity is enhanced when AUF is combined with CDDP. The novelty of this work for cancer research in general and HGSOC in particular is that, as AUF is clinically approved to treat arthritis-related conditions, the compound can be rapidly repositioned as a consolidation therapy following Pt-based standard of care and/or overcome Pt resistant disease. Citation Format: Farah H. Abdalbari, Alicia A. Goyeneche, Elvis M. Jaramillo, Siham Sabri, Carlos M. Telleria. Anticancer effects of the gold complex auranofin on high-grade serous ovarian cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 4066.

The enhancer RNA ADCY10P1 is associated with the progression of ovarian cancer

BackgroundEmerging evidence identifies enhancer RNAs (eRNAs) as a class of regulatory ncRNAs that can contribute to the transcription of target genes. In this study, we used an integrated data analysis method to identify the important role of eRNAs in ovarian cancer (OC).MethodsGene expression profiles and clinical information from The Cancer Genome Atlas (TCGA) database were used for this study. Based on expression analysis using GEPIA2 gene and Kaplan–Meier survival was performed to ensure the significance of the selected enhancer RNA ADCY10P1 in OC. Next, we explored the correlation and clinical significance between ADCY10P1 and target gene NFYA. Furthermore, we evaluated the effects of overexpression of ADCY10P1 on the proliferation, migration, invasion and epithelial-mesenchymal transformation (EMT) of OC cell lines. We also investigated the biological function enrichment score of ADCY10P1 and verified it with OC cell lines. Finally, external validation was conducted, and the prognostic value of the ADCY10P1 in different tumors was demonstrated.ResultsWe selected the eRNA ADCY10P1 associated with OC prognosis, with NFYA as its predicted target gene. Low ADCY10P1 expression was found to be associated with poor overall survival, high histological grade, and advanced stage of OC. Additionally, overexpression of ADCY10P1 inhibited the proliferation, migration, invasion and EMT phenotype of OC cell lines. Furthermore, ADCY10P1 was observed to inhibit glycolysis and fatty acid metabolism, thereby affecting OC progression. Meanwhile, OC tissue samples were externally validated. In addition, the pan-cancer analysis revealed that ADCY10P1 had prognostic value in other cancers.ConclusionsThis study showed that ADCY10P1 plays a key role in OC progression and may facilitate prognosis prediction.

The Role of SOD2 in Migration and Anchorage-Independent Growth of SKOV3 Ovarian Cancer Cells

The 5-year survival rates for ovarian cancer are 93%, 75%, and 30% for localized, regional, and distant tumors, respectively. These vast differences in survival rates underscore the need to identify novel therapeutic targets that are effective at different stages of tumor progression to better treat all patients diagnosed with this deadly disease. Manganese superoxide dismutase (SOD2) is a mitochondrial antioxidant enzyme responsible for eliminating superoxide and preventing oxidative damage to the mitochondria. Recent studies have implicated changes in SOD2 expression levels in multiple cancers, including breast, colorectal, prostate, and head and neck. While studies have begun to unravel the role of SOD2 in ovarian cancer, no one has looked at the specific role SOD2 plays in distinct stages of tumor progression of ovarian cancer. Here, we report SOD2 deficiency (accomplished through utilizing shRNA techniques) results in increased invasive and migratory ability of SKOV3 cells, a commonly used ovarian adenocarcinoma cell line. In contrast, SOD2-deficient SKOV3 cells display abrogated anchorage-independent growth in soft agar. These studies in SKOV3 cells indicate that SOD2 expression hampers invasion and migration critical for early tumor initiation but helps maintain anchorage-independent growth necessary for ovarian cancer metastases. In aggregate, SOD2 plays a context-dependent role in ovarian cancer progression and its utility as a therapeutic target for later-stage anchorage-independent ovarian cancer cells should be further explored. (First online: March 1, 2022)

KDF1 Promoted Proliferation and Metastasis of Epithelial Ovarian Cancer via Wnt/Beta-Catenin Pathway: TCGA-Based Data Mining and Experimental Validation.

Objectives: It has been reported that keratinocyte differentiation factor 1 (KDF1) was related to proliferation, differentiation, and cell cycle. However, the role of KDF1 has not been reported in ovarian cancer. The present study investigated the function and the potential mechanism of KDF1 in ovarian cancer. Methods: We evaluated the prognostic value in ovarian cancer based on data from the Cancer Genome Atlas (TCGA) database. The Kruskal–Wallis test, Wilcoxon signed-rank test, and logistic regression were used to evaluate the relationship between KDF1 expression and clinicopathologic features. The Cox regression and the Kaplan–Meier method were adopted to evaluate prognosis-related factors. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) gene enrichment analysis, and Gene Set Enrichment Analysis (GSEA) were performed to identify the key biological process related to KDF1. Then the expression of KDF1 in ovarian cancer tissues was validated by streptavidin–peroxidase (SP) immunohistochemistry. The proliferation and invasion ability of KDF1 were determined by EdU and Transwell assay, respectively, with KDF1 gene silencing and overexpression. The mRNA expression of KDF1 was determined by qPCR. The protein expression of KDF1 was determined using the Western blot. Methods: By performing differential expression analysis on the ovarian cancer data of the TCGA database, it was found that KDF1 is highly expressed in ovarian cancer patients and associated with poorer overall survival (OS) and progression-free survival (PFS) of ovarian cancer patients. The highly expressed KDF1 may reduce cell adhesion according to GO, KEGG, and GSEA results. After analysis combining the relevant clinical features, we found that the high expression of KDF1 is an independent prognostic factor of ovarian cancer and associated with platinum resistance and tumor metastasis in ovarian cancer. At the same time, the BioGRID database showed that there might be protein–protein interaction between KDF1 and E-cadherin. Then we further validated that the high expression of KDF1 had a close correlation with the stage and grade of ovarian cancer in ovarian cancer tissue chips. Silencing KDF1 inhibited the proliferation and invasion ability of SKOV3 cells. By contrast, ectopic expression of KDF1 promoted the proliferation and invasion ability of A2780 cells. We also found that KDF1 can interact with E-cadherin and regulate the expression of Wnt5A and β-catenin, hence activating Wnt/β-catenin pathway via in vitro and vivo experiments. Conclusions: Based on the bioinformatics analysis, in vitro experiments, and an in vivo study, it is indicated that KDF1 played an important role in ovarian cancer progression and might be a therapeutic target for patients with ovarian cancer.

Recent advances of non-coding RNAs in ovarian cancer prognosis and therapeutics.

Ovarian cancer (OC) is the third most common gynecological malignancy with the highest mortality worldwide. OC is usually diagnosed at an advanced stage, and the standard treatment is surgery combined with platinum or paclitaxel chemotherapy. However, chemoresistance inevitably appears coupled with the easy recurrence and poor prognosis. Thus, early diagnosis, predicting prognosis, and reducing chemoresistance are of great significance for controlling the progression and improving treatment effects of OC. Recently, much insight has been gained into the non-coding RNA (ncRNA) that is employed for RNAs but does not encode a protein, and many types of ncRNAs have been characterized including long-chain non-coding RNAs, microRNAs, and circular RNAs. Accumulating evidence indicates these ncRNAs play very active roles in OC progression and metastasis. In this review, we briefly discuss the ncRNAs as biomarkers for OC prognosis. We focus on the recent advances of ncRNAs as therapeutic targets in preventing OC metastasis, chemoresistance, immune escape, and metabolism. The novel strategies for ncRNAs-targeted therapy are also exploited for improving the survival of OC patients.

Evaluation of Diagnostic Potential of Epigenetically Deregulated MiRNAs in Epithelial Ovarian Cancer.

BackgroundEpithelial ovarian cancer (EOC) is one of the most lethal gynecological malignancies among women worldwide. Early diagnosis of EOC could help in ovarian cancer management. MicroRNAs, a class of small non-coding RNA molecules, are known to be involved in post-transcriptional regulation of ~60% of human genes. Aberrantly expressed miRNAs associated with disease progression are confined in lipid or lipoprotein and secreted as extracellular miRNA in body fluid such as plasma, serum, and urine. MiRNAs are stably present in the circulation and recently have gained an importance to serve as a minimally invasive biomarker for early detection of epithelial ovarian cancer.MethodsGenome-wide methylation pattern of six EOC and two normal ovarian tissue samples revealed differential methylation regions of miRNA gene promoter through MeDIP-NGS sequencing. Based on log2FC and p-value, three hypomethylated miRNAs (miR-205, miR-200c, and miR-141) known to have a potential role in ovarian cancer progression were selected for expression analysis through qRT-PCR. The expression of selected miRNAs was analyzed in 115 tissue (85 EOC, 30 normal) and 65 matched serum (51 EOC and 14 normal) samples.ResultsAll three miRNAs (miR-205, miR-200c, and miR-141) showed significantly higher expression in both tissue and serum cohorts when compared with normal controls (p < 0.0001). The receiver operating characteristic curve analysis of miR-205, miR-200c, and miR-141 has area under the curve (AUC) values of 87.6 (p < 0.0001), 78.2 (p < 0.0001), and 86.0 (p < 0.0001), respectively; in advance-stage serum samples, however, ROC has AUC values of 88.1 (p < 0.0001), 78.9 (p < 0.0001), and 86.7 (p < 0.0001), respectively, in early-stage serum samples. The combined diagnostic potential of the three miRNAs in advance-stage serum samples and early-stage serum samples has AUC values of 95.9 (95% CI: 0.925–1.012; sensitivity = 96.6% and specificity = 80.0%) and 98.1 (95% CI: 0.941–1.021; sensitivity = 90.5% and specificity = 100%), respectively.ConclusionOur data correlate the epigenetic deregulation of the miRNA genes with their expression. In addition, the miRNA panel (miR-205 + miR-200c + miR-141) has a much higher AUC, sensitivity, and specificity to predict EOC at an early stage in both tissue and serum samples.

Identification of GNA12-driven gene signatures and key signaling networks in ovarian cancer.

With the focus on defining the oncogenic network stimulated by lysophosphatidic acid (LPA) in ovarian cancer, the present study sought to interrogate the oncotranscriptome regulated by the LPA-mediated signaling pathway. LPA, LPA-receptor (LPAR) and LPAR-activated G protein 12 α-subunit, encoded by G protein subunit α 12 (GNA12), all serve an important role in ovarian cancer progression. While the general signaling mechanism regulated by LPA/LPAR/GNA12 has previously been characterized, the global transcriptomic network regulated by GNA12 in ovarian cancer pathophysiology remains largely unknown. To define the LPA/LPAR/GNA12-orchestrated oncogenic networks in ovarian cancer, transcriptomic and bioinformatical analyses were conducted using SKOV3 cells, in which the expression of GNA12 was silenced. Array analysis was performed in Agilent SurePrint G3 Human Comparative Genomic Hybridization 8×60 microarray platform. The array results were validated using Kuramochi cells. Gene and functional enrichment analyses were performed using Database for Annotation, Visualization and Integrated Discovery, Search Tool for Retrieval of Interacting Genes and Cytoscape algorithms. The results indicated a paradigm in which GNA12 drove ovarian cancer progression by upregulating a pro-tumorigenic network with AKT1, VEGFA, TGFB1, BCL2L1, STAT3, insulin-like growth factor 1 and growth hormone releasing hormone as critical hub and/or bottleneck nodes. Moreover, GNA12 downregulated a growth-suppressive network involving proteasome 20S subunit (PSM) β6, PSM α6, PSM ATPase 5, ubiquitin conjugating enzyme E2 E1, PSM non-ATPase 10, NDUFA4 mitochondrial complex-associated, NADH:ubiquinone oxidoreductase subunit B8 and anaphase promoting complex subunit 1 as hub or bottleneck nodes. In addition to providing novel insights into the LPA/LPAR/GNA12-regulated oncogenic networks in ovarian cancer, the present study identified several potential nodes in this network that could be assessed for targeted therapy.