Subtypes Of Epithelial Ovarian Cancer Research Articles

MicroRNA Expression Profiling of Epithelial Ovarian Cancer Identifies New Markers of Tumor Subtype.

Epithelial Ovarian Cancer (EOC) is often challenging to diagnose, even though histological examination. MicroRNA (miRNA or miRNA) is bound to the target messenger RNA (mRNA) due to which the mRNA molecules are silenced. The identification of miRNA expression- based EOC subtypes is considered a critical means of prognostication. So far, the studies on EOC subtypes have not been well characterized. This study aimed to confirm the existence of miRNAs in EOC and to assess their potential as clinical biomarkers for EOC. We sampled 25 ovarian tumor tissues from patients with human ovarian tumors (17 malignant; 12 serous EOC, five non-serous EOC, and eight benign ovarian tumors). miRNA microarray detection was performed to identify EOC miRNAs. Real-time PCR was adapted for the validation of differentially expressed miRNAs detected by microarray analysis related to hybridization intensity. The results confirmed that miRNAs exist in EOC, relative expression of EOC miRNAs demonstrated that the upregulation of miR-483-5p, and downregulation of miR-127-3p, and miR- 532-5p were significantly expressed in the malignant group than in the benign group at p < 0.05. Besides, miR-483-5p could also distinguish EOC subtypes between serous EOC and non-serous EOC, with a p < 0.05. A comprehensive miRNA expression profiling can help to refine subtype classification in EOC, opening new opportunities for identifying clinically applicable markers for improved stratification and diagnostics of ovarian tumors.

The Landscape and Therapeutic Implications of Molecular Profiles in Epithelial Ovarian Cancer.

Epithelial ovarian cancer (EOC) affects 43,000 women worldwide every year and has a five-year survival rate of 30%. Mainstay treatment is extensive surgery and chemotherapy. Outcomes could be improved by molecular profiling. We conducted a review of the literature to identify relevant publications on molecular and genetic alterations in EOC. Approximately 15% of all EOCs are due to BRCA1 or BRCA2 mutations. Four histologic subtypes characterized by different mutations have been described: serous, endometrioid, mucinous, and clear-cell. Between 20–30% of high-grade serous EOCs have a BRCA mutation. Tumors with BRCA mutations are unable to repair double-strand DNA breaks, making them more sensitive to platinum-based chemotherapy and to PolyAdenosine Diphosphate-Ribose Polymerase (PARP) inhibitors. Olaparib is a PARP inhibitor with proven efficacy in BRCA-mutated ovarian cancer, but its effectiveness remains to be demonstrated in tumors with a BRCAness (breast cancer) profile (i.e., also including sporadic tumors in patients with deficient DNA repair genes). A universally accepted molecular definition of BRCAness is required to identify optimal theranostic strategies involving PARP inhibitors. Gene expression analyses have led to the identification of four subgroups of high-grade serous EOC: mesenchymal, proliferative, differentiated, and immunoreactive. These subtypes are not mutually exclusive but are correlated with prognosis. They are not yet used in routine clinical practice. A greater understanding of EOC subtypes could improve patient management.

Modelling Epithelial Ovarian Cancer in Mice: Classical and Emerging Approaches.

High-grade serous epithelial ovarian cancer (HGSC) is the most aggressive subtype of epithelial ovarian cancer. The identification of germline and somatic mutations along with genomic information unveiled by The Cancer Genome Atlas (TCGA) and other studies has laid the foundation for establishing preclinical models with high fidelity to the molecular features of HGSC. Notwithstanding such progress, the field of HGSC research still lacks a model that is both robust and widely accessible. In this review, we discuss the recent advancements and utility of HGSC genetically engineered mouse models (GEMMs) to date. Further analysis and critique on alternative approaches to modelling HGSC considers technological advancements in somatic gene editing and modelling prototypic organs, capable of tumorigenesis, on a chip.

Identification and validation of differential plasma proteins levels in epithelial ovarian cancer

Diagnosis of Ovarian cancer (OC) has been a challenge, the purpose, therefore is to identify plasma proteins differentially expressed in epithelial ovarian cancer patients. Human plasma samples from patients with OC (n = 138), benign tumors (n = 20) and controls (n = 238) were used. Tandem Mass Tag (TMT) based quantitative analysis by high resolution mass spectrometry, was followed by validation using Quantibody array and ELISA techniques. 507 plasma proteins showed differential protein levels in OC plasma samples. 21 proteins were validated using Quantibody array. Further, nine proteins (CA125, CFD, CST3, ICAM1, IGFBP2, IGFBP3, SPP1, TSP1 and VEGFA) which showed significant differences in protein levels in Quantibody array analysis were validated using ELISA. In ELISA, the levels of CA125, IGFBP2, ICAM1 and SPP1 were significantly increased and levels of Adipsin and TSP1 were decreased in tumors compared to controls and benign group. Epithelial ovarian cancer diagnosis model combining five markers (CA125, IGFBP2, SPP1, TSP1 and ADI) showed 90.24% sensitivity and 94.87% specificity. In conclusion a panel of 5 plasma proteins has been found to be useful in distinguishing plasma samples from epithelial ovarian cancers from patients with benign tumors and healthy normal subjects. This has the potential as a diagnostic assay for epithelial ovarian cancer. SignificanceThe significance of this case-control study is based on the large and well defined ovarian cancer patient population (epithelial ovarian cancers including serous and mucinous subtypes), age matched controls and benign ovarian tumors. This study incorporates a discovery phase involving quantitative proteomic analysis of immune-depleted plasma followed by two levels of validation studies involving a selected list of proteins using antibody arrays and ELISA. The validations were performed on an independent set of samples comprising of epithelial ovarian cancer subtypes, controls and benign tumors. The multiple marker combination comprising of Adipsin, CA125, IGFBP2, SPP1 and TSP1 identified in the study by ELISA could enable rapid translation to a larger screening study.

Abstract A73: BCL-XL dependency in a subset of ovarian clear-cell carcinoma cell lines

Abstract Clear-cell ovarian carcinoma is a rare histologic subtype of epithelial ovarian cancers. Clear-cell ovarian cancers tend to be less responsive to platinum-based chemotherapy compared to high-grade serous ovarian cancers. In a dataset of large-scale CRISPR knockout and RNAi screens of cancer cell lines (depmap.org), a subset of ovarian clear-cell carcinoma cell lines were sensitive to knockout or knockdown of BCL2L1, encoding antiapoptotic protein BCL-XL. Most clear-cell ovarian cancer cell lines also express BCL2L1 mRNA and protein. We therefore tested a panel of ovarian cancer cell lines for response to BH3 mimetic drugs, which inhibit different members of the BCL-2 family of antiapoptotic proteins. Initial data showed that a subset of ovarian clear-cell carcinoma cell lines was sensitive to single-agent BCL-XL inhibition with A1331852 and dual BCL-2/BCL-XL inhibition with ABT-263. In contrast, these cell lines were relatively insensitive to single-agent BCL-2 inhibition or MCL1 inhibition. We are currently applying BH3 profiling, a functional assay for apoptotic priming, to test the response of ovarian clear-cell carcinoma cell lines to BCL-XL inhibition using a BCL-XL specific peptide, HRK. Collectively, these studies suggest that ovarian clear-cell carcinomas may be sensitive to BCL-XL inhibition, either alone or in combination with chemotherapy. Citation Format: Elizabeth H. Stover, Maya K. Gelbard, Ursula A. Matulonis, Matthew Meyerson. BCL-XL dependency in a subset of ovarian clear-cell carcinoma cell lines [abstract]. In: Proceedings of the AACR Special Conference on Advances in Ovarian Cancer Research; 2019 Sep 13-16, 2019; Atlanta, GA. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(13_Suppl):Abstract nr A73.

Abstract A41: ROR1 is associated with ovarian cancer progression and chemoresistance

Abstract Background: New targets for ovarian cancer treatment are critically needed. The Wnt receptors ROR1 and ROR2 are overexpressed in all subtypes of ovarian cancer and appear to play a role in both the tumor and surrounding microenvironment (1). In vitro studies support the approach of targeting these receptors together to inhibit ovarian cancer migration and invasion (2, 3). Aim: To investigate the role of ROR1 and ROR2 in ovarian cancer progression, survival and chemoresistance, to determine their feasibility as therapeutic targets. Methods: Analysis of RNA-Seq data from publicly available ovarian cancer datasets was performed to determine associations with overall survival and platinum resistance. ROR1 IHC using a recently released monoclonal antibody (4A5, BD Bioscience) was performed on a cohort of ovarian cancer patients. ROR1 and/or ROR2 were silenced in a unique preclinical organotypic model of platinum-resistant ovarian cancer metastasis. Results: There is a significant increase (p=0.01) in ROR1 expression in both primary resistant and acquired resistant (p=0.03) high-grade serous ovarian cancer (HGSOC). ROR2 expression is not significantly associated with chemoresistance. High ROR1 (P=0.002, HR 1.93) or high ROR2 (P=0.004, HR 1.9) expression is associated with a significantly shorter overall survival (OS) in the Tothill cohort (4). Patients expressing both high ROR1 and high ROR2 have the shortest OS (P=0.0003, HR 2.38). ROR1 protein expression was detected in 97% of HGSOC patients via IHC, with 59% of HGSOC expressing “high ROR1” (IHC score 2 or 3). Overall, patients with higher-grade tumors expressed significantly higher ROR1 levels (P=0.001) than patients with low-grade tumors. Silencing ROR1 and ROR2 in combination inhibits adhesion and invasion of platinum resistant ovarian cancer in a 3D organotypic coculture model. Conclusion: Our data support targeting both ROR1 and ROR2 as a new approach to treating ovarian cancer. The development of a number of monoclonal antibodies targeting ROR1 and ROR2 that are currently in phase 1 trials for other tumor types makes this clinically feasible in the future. These data also suggest that this may be most effective in the context of HGSOC with platinum resistance.

Abstract IA25: Personalizing treatment for women with rare epithelial ovarian cancers (EOC): Lessons learned

Abstract Prior to the mid-2000s, all epithelial ovarian cancer subtypes were treated identically worldwide. In 2005, the Gynecologic Oncology Group (GOG) established the Rare Tumor Committee. Over the past almost 15 years, GOG (subsequently merged into NRG Oncology) has been a leader in the development of clinical trials for rare gynecologic tumors, and a number of lessons have been learned. Initially the Rare Tumor Committee was faced with the challenge of determining on which rare gynecologic cancers it should focus. Lesson 1: There is no universal definition of a rare cancer. Ultimately, the group decided to concentrate on trials of rare EOC. Prior to this point, there were essentially no prospective data on these histotypes. Lesson 2: The study of rare EOC was energized by a number of converging factors. Refinement of histopathologic criteria, advances in the molecular biology, and publication of hypothesis-generating observational studies all played a major role in moving the field forward. Lesson 3: Significant challenges and barriers to conducting clinical trials of rare cancers exist and need to be fully understood. These include small numbers of cases, long accrual times, few interested investigators, less attention by the scientific community, low funding priority, low priority by pharma, fewer patient advocates, and lack of standard bioinformatics methods and trial designs. Lesson 4: In designing rare EOC clinical trials, one must balance scientific value with feasibility. Over time and with trial and error, it became obvious that accrual to clinical trials for recurrent clear-cell and low-grade serous ovarian cancers was completely feasible, but the unexpected extreme rarity of mucinous ovarian cancer led to a failed international trial. Lesson 5: Trials for rare EOC in the front-line or salvage setting may have different implications for feasibility. Front-line trials for clear-cell ovarian cancer, both randomized and nonrandomized, have been feasible. Front-line randomized trials for mucinous ovarian cancers do not appear to be feasible. A new clinical trial for front-line treatment of low-grade serous ovarian cancer has recently been activated; feasibility is as yet unknown. Lesson 6: Accurate pathologic diagnosis is essential to quality rare EOC clinical trials. In some instances, prospective digital pathology review was used as an eligibility criterion to optimize efficiency. Lesson 7: Characterization of the molecular signatures of rare EOC and availability of targeted agents significantly facilitated the development of innovative clinical trials. We now have excellent information regarding the common molecular aberrations in clear-cell carcinoma, low-grade serous carcinoma, and mucinous carcinoma. Lesson 8: Strategies for clinical trial design for rare EOC should include consideration of certain principles. These principles include determination of feasibility of phase II versus randomized phase II versus phase III designs; clinical trials that seek large benefits in selected populations with small sample size; tolerating a higher degree of uncertainty; relaxation of type I and type II errors; adaptive and Bayesian trial designs; rigorous use of early stopping rules; use of surrogate endpoints (response, PFS, or DFS, etc.); full exploitation of modern imaging techniques; strong translational research endpoints; and, in absence of known effective standard treatment, use of randomized phase II design to compare two or more experimental treatments. Finally, Lesson 9: Organizational aspects may be critical in the conduct of rare EOC trials. Key ingredients for successful conduct of rare tumor trials may include national or international networks involving centers of excellence; use of cancer registries to identify, screen, and recruit patients; utilization of retrospective or observational studies for hypothesis-generating data; quality tumor repositories; understanding differences in regulatory and funding issues across the world; and regular consultations between regulatory bodies, pharmaceutical companies, patient advocates, and investigators. All of these lessons will hopefully assist future investigators in the development of clinical trials for rare EOC. Citation Format: David M. Gershenson. Personalizing treatment for women with rare epithelial ovarian cancers (EOC): Lessons learned [abstract]. In: Proceedings of the AACR Special Conference on Advances in Ovarian Cancer Research; 2019 Sep 13-16, 2019; Atlanta, GA. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(13_Suppl):Abstract nr IA25.

Abstract A20: Characterizing chromosome instability in chemonaïve, chemosensitive, and chemoresistant high-grade serous ovarian cancer

Abstract High-grade serous ovarian cancer (HGSOC) is the most aggressive epithelial ovarian cancer subtype, and &amp;gt;75% of patients experience tumor recurrence following initial treatment, often with drug-resistant disease. Unfortunately, the aberrant events driving tumor progression, recurrence, and multidrug resistance in HGSOC remain largely unknown. Chromosome instability (CIN) is defined as an increased rate at which whole chromosomes (or large fragments) are gained or lost, and in many cancer types CIN is associated with tumor initiation, disease recurrence, multidrug resistance, and poor patient prognosis. Conceptually, the ongoing chromosome changes associated with CIN promote the production of genetically distinct daughter cells and drive cell-to-cell heterogeneity. As CIN remains largely unstudied in HGSOC, we now seek to characterize the prevalence and dynamics of CIN in chemonaïve, chemosensitive, and chemoresistant HGSOC patient samples, including samples isolated from ascites (metastatic cells) and solid tumors (primary tumor). Using single-cell quantitative imaging techniques, we evaluated CIN by assessing CIN phenotypes, including changes in nuclear areas and chromosome numbers. Changes in nuclear areas and increases in cell-to-cell heterogeneity are suggestive of CIN. Next, we employed fluorescence in situ hybridization and chromosome enumeration probes (CEPs) recognizing pericentric regions of chromosomes 8, 11, and 17 to quantify changes in chromosome numbers. Deviations from the expected number of two CEP foci/chromosome/nucleus (i.e., diploid state) are indicative of CIN. CEP specificity was validated within diploid and aneuploid fallopian tube (FT) secretory epithelial cell lines, a cell type of origin for HGSOC. The diploid FT cell lines show two CEPs/chromosome/nucleus and the aneuploid FT cell lines show an aberrant number of CEPs/chromosome/nucleus. CEPs are now being employed in HGSOC ascites samples and solid tumors within a HGSOC tissue microarray. Preliminary data show that nuclear areas and CEP numbers are heterogeneous and dynamic over time. More specifically, our data show CIN is highly prevalent in HGSOC cells isolated from ascites, increases with disease progression and drug resistance, and decreases in response to treatment. Additionally, we show that solid tumor samples (primary tumor) typically contain more frequent gains and/or losses in CEP foci (i.e., higher level of CIN) compared to the ascites samples (metastatic cells). Importantly, characterizing the prevalence of CIN in HGSOC will help researchers understand the association between CIN and tumor development, progression, response, and acquisition of drug resistance. Citation Format: Claire Morden, Ally Farrell, Mirka Sliwowski, Zelda Lichtensztejn, Mark Nachtigal, Kirk McManus. Characterizing chromosome instability in chemonaïve, chemosensitive, and chemoresistant high-grade serous ovarian cancer [abstract]. In: Proceedings of the AACR Special Conference on Advances in Ovarian Cancer Research; 2019 Sep 13-16, 2019; Atlanta, GA. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(13_Suppl):Abstract nr A20.

Differences in immune-related gene expressions and tumor-infiltrating lymphocytes according to chemotherapeutic response in ovarian high-grade serous carcinoma

BackgroundHigh-grade serous carcinoma (HGSC) of the ovary is the most common subtype of epithelial ovarian cancer (EOC) and has an overall poor prognosis. There is increasing awareness of the importance of immune cell populations and tumor-infiltrating lymphocytes (TILs) in various immune pathways in the tumor microenvironment. The present study evaluated immune-related gene expressions and TIL levels, as well as associated chemotherapeutic responses, to elucidate the correlation between gene expression and TIL levels in HGSC.Materials and methodsFresh tissue samples from 12 HGSC patients were included in this study. Depending on their response to adjuvant chemotherapy, the patients were divided into two groups: chemosensitive (CS) or chemoresistant (CR). The expression levels of 770 genes were analyzed using the nCounter® PanCancer Immune Profiling Panel of the NanoString nCounter® Analysis System. Quantitative real-time polymerase chain reaction (qPCR) was performed to validate the NanoString data obtained. The TIL levels in representative sections were examined via hematoxylin and eosin staining. Gene and TIL levels were subsequently correlated with the chemotherapeutic response.ResultsSeveral genes were differentially expressed in the two study groups. Eleven representative genes were selected for further evaluation. Of those, 9 genes (IRF1, CXCL9, LTB, CCL5, IL-8, GZMA, PSMB9, CD38, and VCAM1) were significantly overexpressed in the CS group; whereas expressions of 2 genes (CD24 and CD164) were increased in the CR group. Results of qPCR were consistent with those of the NanoString nCounter® analysis. Stromal TIL levels were significantly associated with adjuvant chemotherapeutic response (p = 0.001).ConclusionsSignificant differences between the CS and CR groups were observed in the expression levels of immune-related genes. Immune-related gene expressions were significantly higher in the CS group, which also had higher levels of TILs. We, therefore, suggest that, in patients with HGSC, immune-related gene expressions and TIL levels may be associated with chemotherapeutic sensitivity.

Clinicopathological and prognostic significance of caveolin-1 and ATG4C expression in the epithelial ovarian cancer.

Altered expression of caveolin-1 (CAV1) and autophagy marker ATG4C is observed in various types of human cancers. However, the clinical significance of CAV1 and ATG4C expression in epithelial ovarian cancer (EOC) remains largely unknown. The present study aims to explore the clinicopathological value and prognostic significance of CAV1 and ATG4C expression in EOC. The expression pattern and prognostic value of CAV1 and ATG4C mRNA in EOC were analyzed using data from the Cancer Genome Atlas (TCGA) database (N = 373). In addition, immunohistochemistry analysis was performed to detect and assay the expression of CAV1 and ATG4C proteins in tissue microarray of EOC. Based on TCGA data, Kaplan-Meier analysis indicated that patients with low CAV1 mRNA (p = 0.021) and high ATG4C mRNA (p = 0.018) expression had a significantly shorter overall survival (OS). Cox regression analysis demonstrated that the expression levels of CAV1 (p = 0.023) and ATG4C mRNA (p = 0.040) were independent prognostic factors for OS in EOC. In addition, the Concordance Index of the nomogram for OS prediction was 0.660. Immunohistochemical analysis showed the expression levels of stromal CAV1 and cancerous ATG4C proteins, and high expression of both CAV1 and ATG4C protein in the stroma were found to significantly correlate with the histologic subtypes of EOC, especially with serous subtype. Decreased expression of CAV1 mRNA and increased expression of ATG4C mRNA in EOC can predict poor overall survival. The expression levels of CAV1 protein in stromal cells and ATG4C protein in cancer cells are significantly associated with histologic subtypes of EOC. These findings suggest that CAV1 and ATG4C serve as useful prognostic biomarkers and candidate therapeutic targets in EOC.

ABCC4/MRP4 contributes to the aggressiveness of Myc-associated epithelial ovarian cancer.

Epithelial ovarian cancer (EOC) is a complex disease comprising discrete histological and molecular subtypes, for which survival rates remain unacceptably low. Tailored approaches for this deadly heterogeneous disease are urgently needed. Efflux pumps belonging to the ATP-binding cassette (ABC) family of transporters are known for roles in both drug resistance and cancer biology and are also highly targetable. Here we have investigated the association of ABCC4/MRP4 expression to clinical outcome and its biological function in endometrioid and serous tumors, common histological subtypes of EOC. We found high expression of ABCC4/MRP4, previously shown to be directly regulated by c-Myc/N-Myc, was associated with poor prognosis in endometrioid EOC (P = .001) as well as in a subset of serous EOC with a "high-MYCN" profile (C5/proliferative; P = .019). Transient siRNA-mediated suppression of MRP4 in EOC cells led to reduced growth, migration and invasion, with the effects being most pronounced in endometrioid and C5-like serous cells compared to non-C5 serous EOC cells. Sustained knockdown of MRP4 also sensitized endometrioid cells to MRP4 substrate drugs. Furthermore, suppression of MRP4 decreased the growth of patient-derived EOC cells in vivo. Together, our findings provide the first evidence that MRP4 plays an important role in the biology of Myc-associated ovarian tumors and highlight this transporter as a potential therapeutic target for EOC.

EMT-inducing transcription factor ZEB1-associated resistance to the BCL-2/BCL-XL inhibitor is overcome by BIM upregulation in ovarian clear cell carcinoma cells

Ovarian clear cell carcinoma (OCCC) is an aggressive subtype of epithelial ovarian cancer, which generally exhibits chemoresistance. Effective therapy for OCCC is currently unavailable, requiring the development of new therapeutic strategies. ABT-263 (navitoclax), an inhibitor of the anti-apoptotic BCL-2/BCL-XL, has a potent ability of inducing death in cancer cells; however, the therapeutic effect of ABT-263 in OCCC remains unclear. Epithelial cells undergo epithelial-mesenchymal transition (EMT) to acquire a mesenchymal phenotype, which is known to contribute to the development of resistance against therapeutic agents. In this study, we revealed that the sensitivity of OCCC cells to ABT-263 was associated with the epithelial/mesenchymal status of the cells. While the OCCC cells with an epithelial phenotype were ABT-263-sensitive, those with a mesenchymal phenotype were ABT-263-resistant, which was accompanied by an insufficient expression of the pro-apoptotic BH3 protein BIM. Mechanistically, the EMT-inducing transcription factor, ZEB1 down-regulated BIM transcription by binding to BIM promoter, resulting in resistance to ABT-263. It is noteworthy that ZEB1-associated ABT-263 resistance was overcome by an HDAC inhibitor, FK228 (romidepsin), through the up-regulation of BIM. In summary, our study provides evidence for a mechanism for ABT-263 resistance in OCCC cells as well as a potential therapeutic strategy to overcome it.

Ovarian Cancer, Cancer Stem Cells and Current Treatment Strategies: A Potential Role of Magmas in the Current Treatment Methods.

Epithelial ovarian cancer (EOC) constitutes 90% of ovarian cancers (OC) and is the eighth most common cause of cancer-related death in women. The cancer histologically and genetically is very complex having a high degree of tumour heterogeneity. The pathogenic variability in OC causes significant impediments in effectively treating patients, resulting in a dismal prognosis. Disease progression is predominantly influenced by the peritoneal tumour microenvironment rather than properties of the tumor and is the major contributor to prognosis. Standard treatment of OC patients consists of debulking surgery, followed by chemotherapy, which in most cases end in recurrent chemoresistant disease. This review discusses the different origins of high-grade serous ovarian cancer (HGSOC), the major sub-type of EOC. Tumour heterogeneity, genetic/epigenetic changes, and cancer stem cells (CSC) in facilitating HGSOC progression and their contribution in the circumvention of therapy treatments are included. Several new treatment strategies are discussed including our preliminary proof of concept study describing the role of mitochondria-associated granulocyte macrophage colony-stimulating factor signaling protein (Magmas) in HGSOC and its unique potential role in chemotherapy-resistant disease.

CCNE1 and BRD4 co-amplification in high-grade serous ovarian cancer is associated with poor clinical outcomes

ObjectiveHigh-grade serous ovarian cancer (HGSOC) is the most common and lethal histological subtype of epithelial ovarian cancer. HGSOC with cyclin E1 gene (CCNE1) amplification and bromodomain and extraterminal 4 (BRD4) amplification have been associated with poor outcomes. Our objective was to evaluate clinical outcomes of HGSOC with co-amplification of CCNE1 and BRD4 and high protein expression of cyclin E and BRD4. MethodsCopy number amplification data were extracted from The Cancer Genome Atlas (TCGA) for 579 HGSOC. Reverse phase protein array (RPPA) TCGA data were used to determine cyclin E and BRD4 protein expression in 482 HGSOC. Cyclin E and BRD4 protein expression by immunohistochemistry (IHC) was evaluated in a tissue microarray (TMA) of 110 HGSOC. Measured clinical outcomes were survival and platinum sensitivity. ResultsOf 30% of HGSOC with amplifications in CCNE1 or BRD4, 8% have both CCNE1 and BRD4 amplification. Protein expression of cyclin E and BRD4 are positively correlated, both by RPPA (r = 0.23; p < 0.001) and by IHC (r = 0.21; p = 0.025). Patients with CCNE1 and BRD4 co-amplified HGSOC have worse overall survival than patients without amplifications, 39.94 vs 48.06 months (p = 0.029). High protein expression of cyclin E, but not BRD4, was associated with poor overall survival (HR 1.62, 1.04–2.53, p = 0.033) and platinum resistance (p = 0.016). ConclusionHGSOC with CCNE1 and BRD4 co-amplification are associated with poor overall survival. Further studies are warranted to determine the use of protein expression by IHC as a surrogate marker for CCNE1 and BRD4 co-amplified HGSOC.

Subtype specific biomarkers associated with chemoresistance in epithelial ovarian cancer.

In spite of the advent of many high throughput technologies, tumor tissue biomarkers are still the gold standard for diagnosis and prognosis of different malignancies including epithelial ovarian cancer (EOC). EOC is a heterogeneous disease comprised of five major subtypes which show distinct clinicopathological features and therapy response. Acquirement of chemoresistance toward therapy is a major challenge for successful treatment outcome in EOC patients. Several markers have been tested by immunohistochemical method to evaluate their prognostic merit to predict clinical outcome. However, a vast majority of such markers have been assessed for high-grade serous and clear cell ovarian cancer, among all subtypes of EOC. The current review elaborates upon those biomarkers that can potentially predict chemoresistance with subtype specificity.

Long Non-Coding RNA MAGI2-AS3 is a New Player with a Tumor Suppressive Role in High Grade Serous Ovarian Carcinoma.

High-Grade Serous Ovarian Carcinoma (HGSC) is the most incidental and lethal subtype of epithelial ovarian cancer (EOC) with a high mortality rate of nearly 65%. Recent findings aimed at understanding the pathogenesis of HGSC have attributed its principal source as the Fallopian Tube (FT). To further comprehend the exact mechanism of carcinogenesis, which is still less known, we performed a transcriptome analysis comparing FT and HGSC. Our study aims at exploring new players involved in the development of HGSC from FT, along with their signaling network, and we chose to focus on non-coding RNAs. Non-coding RNAs (ncRNAs) are increasingly observed to be the major regulators of several cellular processes and could have key functions as biological markers, as well as even a therapeutic approach. The most physiologically relevant and significantly dysregulated non-coding RNAs were identified bioinformatically. After analyzing the trend in HGSC and other cancers, MAGI2-AS3 was observed to be an important player in EOC. We assessed its tumor-suppressive role in EOC by means of various assays. Further, we mapped its signaling pathway using its role as a miRNA sponge to predict the miRNAs binding to MAGI2AS3 and showed it experimentally. We conclude that MAGI2-AS3 acts as a tumor suppressor in EOC, specifically in HGSC by sponging miR-15-5p, miR-374a-5p and miR-374b-5p, and altering downstream signaling of certain mRNAs through a ceRNA network.

Clinicopathologic characteristics and survival outcomes in neuroendocrine carcinoma of the ovary

ObjectiveNeuroendocrine tumors are rare in the ovary. Definitive epidemiologic and prognostic information for neuroendocrine carcinoma of the ovary is lacking. This retrospective population-based study aimed to elucidate the demographic and...

Germline mutations in Thai patients with nonmucinous epithelial ovarian cancer.

BACKGROUNDGenetic testing is widely recommended for all epithelial ovarian cancer (EOC) patients. However, an increased probability of identifying germline mutations has been reported in selected patients with risk factors such as a family history or personal history of cancer and high-grade serous carcinoma (HGSC) subtype. HGSC has been reported to be the most common subtype of EOC worldwide (approximately 70%). However, this subtype is less prevalent in Thai patients (reported as only 20%). The difference in the distribution of various subtypes of EOC may reflect the incidence of germline mutations in Thai EOC patients.AIMTo evaluate the frequencies of germline mutations in EOC patients and to compare the frequencies in those with and without clinical risk factors for hereditary ovarian cancer.METHODSThis cross-sectional study included 112 nonmucinous EOC patients who underwent primary surgery at our tertiary care hospital. Clinical risk factors for hereditary ovarian cancer were defined as follows: Age below 40 years, a significant family history of cancer, synchronous ovarian and endometrial cancer, and HGSC. Comprehensive germline mutations were detected by next-generation sequencing.RESULTSOf a total of 112 patients, 82 (73.2%) patients had ≥ 1 risk factor and 30 (26.8%) patients had no risk factors. Germline mutations were detected in 26 patients: 20 (17.8%) patients had BRCA1/2 mutations, but 6 (5.4%) patients had mutations in other genes, including 1 in MLH1, 1 in MSH2, 1 in RAD51C, 2 in ATM and 1 in CDH1. Germline mutations were only detected in patients with risk factors (26 of 82, 31.7%), not in patients without risk factors (P < 0.001). A significant family history of cancer and HGSC were the only two significant risk factors associated with a higher proportion of germline mutations (56.3% vs 10% for those with and without a history of cancer, respectively, 40.8% vs 9.5% for those with and without HGSC). Germline BRCA mutations were detected in 38.8% of patients with HGSC but in only 1.6% of those with non-HGSC. An age below 40 years, personal history of breast cancer, and synchronous ovarian and endometrial cancer were not significant factors (14.3% vs 23.5%, 33.3% vs 21%, 22.2% vs 22.3%).CONCLUSIONApproximately one-third of EOC patients with risk factors had germline mutations. Almost all germline BRCA mutations were found in patients with the HGSC subtype. Selected patients with HGSC and a family history of cancer should be initially considered for genetic analysis in Thailand.

Analysis of gene expression signatures identifies prognostic and functionally distinct ovarian clear cell carcinoma subtypes.

BackgroundOvarian clear cell carcinoma (OCCC) is a histological subtype of epithelial ovarian cancer (EOC) with distinct pathological, biological, and molecular features. OCCCs are more resistant to conventional treatment regimen of EOC and have the worst stage-adjusted prognosis amongst EOC subtypes. As the OCCC incidence rate in Asian populations has significantly increased in recent decades, it is critical to elucidate its molecular features that could lead to OCCC-tailored therapeutic strategies.MethodsGene expression profiles of 222 OCCC were analyzed by hierarchical clustering and statistical analyses.FindingsWe identified two OCCC gene expression subtypes: EpiCC—epithelial-like, which is associated with early-stage disease, with a relatively higher rate of gene mutations in the SWI/SNF complex; and MesCC—mesenchymal-like, associated with late-stage and higher enrichment of immune-related pathway activity. Genetic, copy number and transcriptomic analyses showed that both EpiCC and MesCC carried OCCC-associated aberrations. The EpiCC/MesCC classification was reproducible in validation cohorts and OCCC cell lines. MesCC tumors had a poorer progression-free survival (PFS) than EpiCC tumors (HR: 3·0, p = 0·0006). Functional assays in cell lines showed that the MesCC subtype was more proliferative and more anoikis-resistant than the EpiCC. By applying the EpiCC/MesCC classification to the TCGA renal clear cell carcinoma cohort, our results indicated interoperability of the subtyping scheme, and revealed preferential drug response of MesCC to bevacizumab.InterpretationThe EpiCC/MesCC classification shows promise for prognostic and therapeutic stratification in OCCC patients and warrants further investigation in the context of OCCC gene expression subtype-tailored treatment strategies.

Comparative\xa0transcriptome analysis of matched primary and distant metastatic ovarian carcinoma

BackgroundHigh grade serous ovarian carcinoma (HGSOC) is the most common subtype of epithelial ovarian cancers (EOC) with poor prognosis. In most cases EOC is widely disseminated at the time of diagnosis. Despite the optimal cytoreductive surgery and chemotherapy most patients develop chemoresistance, and the 5-year overall survival being only 25–35%.MethodsHere we analyzed the gene expression profiles of 10 primary HGSOC tumors and 10 related omental metastases using RNA sequencing and identified 100 differentially expressed genes.ResultsThe differentially expressed genes were associated with decreased embryogenesis and vasculogenesis and increased cellular proliferation and organismal death. Top upstream regulators responsible for this gene signature were NR5A1, GATA4, FOXL2, TP53 and BMP7. A subset of these genes were highly expressed in the ovarian cancer among the cancer transcriptomes of The Cancer Genome Atlas. Importantly, the metastatic gene signature was suggestive of poor survival in TCGA data based on gene enrichment analysis.ConclusionBy comparing the gene expression profiles of primary HGSOC tumors and their matched metastasis, we provide evidence that a signature of 100 genes is able to separate these two sample types and potentially predict patient survival. Our study identifies functional categories of genes and transcription factors that could play important roles in promoting metastases and serve as markers for cancer prognosis.