The origin and pathogenesis of epithelial ovarian cancer: a proposed unifying theory

Beyond Sterilization: A Comprehensive Review on the Safety and Efficacy of Opportunistic Salpingectomy as a Preventative Strategy for Ovarian Cancer

Ovarian cancer (OC) is Canada's third most common gynecological cancer, with an estimated 3000 new cases and 1950 deaths projected in 2022. No effective screening has been found to identify OC, especially the most common subtype, high-grade serous carcinoma (HGSC), at an earlier, curable stage. In patients with hereditary predispositions such as BRCA mutations, the rates of HGSC are significantly elevated, leading to the use of risk-reducing salpingo-oophorectomy as the key preventative intervention. Although surgery has been shown to prevent HGSC in high-risk women, the associated premature menopause has adverse long-term sequelae and mortality due to non-cancer causes. The fact that 75% of HGSCs are sporadic means that most women diagnosed with HGSC will not have had the option to avail of either screening or prevention. Recent research suggests that the fimbrial distal fallopian tube is the most likely origin of HGSC. This has led to the development of a prevention plan for the general population: opportunistic salpingectomy, the removal of both fallopian tubes. This article aims to compile and review the studies evaluating the effect of opportunistic salpingectomy on surgical-related complications, ovarian reserve, cost, and OC incidence when performed along with hysterectomy or instead of tubal ligation in the general population.

Assessment of Fallopian Tube Epithelium Features Derived from Induced Pluripotent Stem Cells of Both Fallopian Tube and Skin Origins

Fallopian tube epithelial cells (FTECs) play a significant role in the development of high-grade serous ovarian cancer (HGSOC), but their utilization in in vitro experiments presents challenges. To address these limitations, induced pluripotent stem cells (iPSCs) have been employed as a potential solution, driven by the hypothesis that orthologous iPSCs may offer superior differentiation capabilities compared with their non-orthologous counterparts. Our objective was to generate iPSCs from FTECs, referred to as FTEC-iPSCs, and compare their differentiation potential with iPSCs derived from skin keratinocytes (NHEK). By introducing a four-factor Sendai virus transduction system, we successfully derived iPSCs from FTECs. To assess the differentiation capacity of iPSCs, we utilized embryoid body formation, revealing positive immunohistochemical staining for markers representing the three germ layers. In vivo tumorigenesis evaluation further validated the pluripotency of iPSCs, as evidenced by the formation of tumors in immunodeficient mice, with histological analysis confirming the presence of tissues from all three germ layers. Quantitative polymerase chain reaction (qPCR) analysis illuminated a sequential shift in gene expression, encompassing pluripotent, mesodermal, and intermediate mesoderm-related genes, during the iPSC differentiation process into FTECs. Notably, the introduction of WNT3A following intermediate mesoderm differentiation steered the cells toward a FTEC phenotype, supported by the expression of FTEC-related markers and the formation of tubule-like structures. In specific culture conditions, the expression of FTEC-related genes was comparable in FTECs derived from FTEC-iPSCs compared with those derived from NHEK-iPSCs. To conclude, our study successfully generated iPSCs from FTECs, demonstrating their capacity for FTEC differentiation. Furthermore, iPSCs originating from orthologous cell sources exhibited comparable differentiation capabilities. These findings hold promise for using iPSCs in modeling and investigating diseases associated with these specific cell types.

Reevaluating the Role of Progesterone in Ovarian Cancer: Is Progesterone Always Protective?

Ovarian cancer (OC) represents a collection of rare but lethal gynecologic cancers where the difficulty of early detection due to an often-subtle range of abdominal symptoms contributes to high fatality rates. With the exception of BRCA1/2 mutation carriers, OC most often manifests as a post-menopausal disease, a time in which the ovaries regress and circulating reproductive hormones diminish. Progesterone is thought to be a "protective" hormone that counters the proliferative actions of estrogen, as can be observed in the uterus or breast. Like other steroid hormone receptor family members, the transcriptional activity of the nuclear progesterone receptor (nPR) may be ligand dependent or independent and is fully integrated with other ubiquitous cell signaling pathways often altered in cancers. Emerging evidence in OC models challenges the singular protective role of progesterone/nPR. Herein, we integrate the historical perspective of progesterone on OC development and progression with exciting new research findings and critical interpretations to help paint a broader picture of the role of progesterone and nPR signaling in OC. We hope to alleviate some of the controversy around the role of progesterone and give insight into the importance of nPR actions in disease progression. A new perspective on the role of progesterone and nPR signaling integration will raise awareness to the complexity of nPRs and nPR-driven gene regulation in OC, help to reveal novel biomarkers, and lend critical knowledge for the development of better therapeutic strategies.

Potential drug repurposing of ruxolitinib to inhibit the JAK/STAT pathway for the treatment of patients with epithelial ovarian cancer

AIM

This review aimed to describe the potential for therapeutic targeting of the JAK/STAT signaling pathway by repurposing the clinically-approved JAK inhibitor ruxolitinib in the patients with epithelial ovarian cancer (OC) setting.

METHODS

We reviewed publications that focus on the inhibition of the JAK/STAT pathway in hematological and solid malignancies including OC.

RESULTS

Preclinical studies showed that ruxolitinib effectively reduces OC cell viability and metastasis and enhances the anti-tumor activity of chemotherapy drugs. There are a number of recent clinical trials exploring the role of JAK/STAT inhibition in solid cancers including OC. Early results have not adequately supported efficacy in solid tumors. However, there are preclinical data and clinical studies supporting the use of ruxolitinib in combination with both chemotherapy and other targeted drugs in OC setting.

CONCLUSION

Inflammatory conditions and persistent activation of the JAK/STAT pathway are associated with tumourigenesis and chemoresistance, and therapeutic blockade of this pathway shows promising results. For women with OC, clinical investigation exploring the role of ruxolitinib in combination with chemotherapy agents or other targeted therapeutics is warranted.

Salpingectomy for the Primary Prevention of Ovarian Cancer: A Systematic Review

Importance

Most ovarian cancers originate in the fimbriated end of the fallopian tube. This has led to the hypothesis that surgical resection of the fallopian tubes at the time of gynecologic and nongynecologic surgical procedures-referred to as an opportunistic salpingectomy-may prevent the development of epithelial ovarian cancer for women at an average risk of developing the disease.

Objective

To compile a comprehensive, state-of-the-science review examining the current landscape of performing bilateral salpingectomy for ovarian cancer prevention.

Evidence Review

A systematic review of the literature was performed on March 4, 2022, to identify studies examining salpingectomy for ovarian cancer prevention. This review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) 2020 statement. Four databases were selected: PubMed via the National Library of Medicine's PubMed.gov, Embase via Elsevier's Embase.com, Cochrane Central Register of Controlled Trials (CENTRAL) via Wiley's Cochrane Library, and Northern Light Life Sciences Conference Abstracts via Ovid. A total of 20 gray literature sources, including 1 database, 2 registers, 1 repository, 1 index, 1 archive, 1 preprint server, 1 agency, and 12 organizations, were also searched.

Findings

The initial search produced 1089 results; a total of 158 publications were included in the final review. Salpingectomy has been associated with ovarian cancer risk reduction of approximately 80%. Studies have demonstrated that salpingectomy was safe, cost-effective, and was not associated with an earlier age of menopause onset. With widespread implementation, salpingectomy has the potential to reduce ovarian cancer mortality in the US by an estimated 15%. Both physician and patient awareness regarding the adnexa as the origin for most ovarian cancers, as well as the existence of salpingectomy and its potential benefits in reducing ovarian cancer risk, has increased during the past decade. Raising awareness and developing effective implementation strategies are essential.

Conclusions and Relevance

The results of this systematic review suggest that bilateral salpingectomy for ovarian cancer prevention was safe and feasible and has the potential to be a cost-effective and cost-saving strategy across the population. Prospective studies to demonstrate long-term survival outcomes and feasibility in nongynecologic surgical procedures are warranted.

From seeds to survival rates: investigating Linum usitatissimum's potential against ovarian cancer through network pharmacology

Ovarian cancer is a malignant tumor that primarily forms in the ovaries. It often goes undetected until it has spread to the pelvis and abdomen, making it more challenging to treat and often fatal. Historically, natural products and their structural analogues have played a pivotal role in pharmacotherapy, especially for cancer. Numerous studies have demonstrated the therapeutic potential of Linum usitatissimum against ovarian cancer, but the specific molecular mechanisms remain elusive. This study combines data mining, network pharmacology, and molecular docking analysis to pioneer an innovative approach for ovarian cancer treatment by identifying potent phytochemicals. Findings of current study revealed that Apigenin, Vitamin E, Palmitic acid, Riboflavin, Isolariciresinol, 5-Dehydro-avenasterol, Cholesterol, Pantothenic acid, Nicotinic acid, Campesterol, Beta-Sitosterol, Stigmasterol, Daucosterol, and Vitexin suppress tumor growth by influencing AKT1, JUN, EGFR, and VEGFA. Kaplan-Meier survival analysis spotlighted AKT1, JUN, EGFR, and VEGFA as potential diagnostic and prognostic biomarkers for ovarian cancer. However, it is imperative to conduct in vivo and in vitro examinations to ascertain the pharmacokinetics and biosafety profiles, bolstering the candidacy of L. usitatissimum in ovarian cancer therapeutics.

An epigenetic hypothesis for ovarian cancer prevention by oral contraceptive pill use

BACKGROUND

Ovarian cancer is the second most common gynecological cancer type after uterine cancers. In 2020, according to worldwide statistics, there were more than 313,000 new cases of ovarian cancer. Most concerning with ovarian cancer is the poor overall survival, with only 30% of patients surviving for longer than 5 years after diagnosis. The reason for this poor outcome includes late diagnosis due to non-specific symptoms and a lack of any highly effective biomarkers of the early stages of ovarian carcinogenesis. However, it is important to note that some modifiable lifestyle factors can be preventative [pregnancy, breastfeeding and combined oral contraceptives pill (COCP) use].

RESULTS

There is now increasing data reporting the role of epigenetic changes, which are detectable in ovarian cancer tumors, suggesting the possibility that epigenetics may also play a key role in the mechanism of long-term effective prevention of ovarian cancer. To our knowledge, there is a lack of high-quality data on the molecular mechanisms of ovarian cancer prevention, although several hypotheses have been proposed.

CONCLUSIONS

This review focusses on the evidence for a proposed novel hypothesis-that COCPs act as a chemoprevention through the impact on the epigenome of the cells of origin of ovarian cancer-fallopian tubes epithelium.

Targeting endoplasmic reticulum stress signaling in ovarian cancer therapy

The endoplasmic reticulum (ER), an organelle present in various eukaryotic cells, is responsible for intracellular protein synthesis, post-translational modification, and folding and transport, as well as the regulation of lipid and steroid metabolism and Ca2+ homeostasis. Hypoxia, nutrient deficiency, and a low pH tumor microenvironment lead to the accumulation of misfolded or unfolded proteins in the ER, thus activating ER stress (ERS) and the unfolded protein response, and resulting in either restoration of cellular homeostasis or cell death. ERS plays a crucial role in cancer oncogenesis, progression, and response to therapies. This article reviews current studies relating ERS to ovarian cancer, the most lethal gynecologic malignancy among women globally, and discusses pharmacological agents and possible targets for therapeutic intervention.

Incessant ovulation: a review of its importance in predicting cancer risk

Estrous cycles are recurring changes in therian mammals induced by estrogen, progesterone, and other hormones culminating in endometrial proliferation, ovulation, and implantation if fertilization occurred. In women, the estrous cycle is the menstrual cycle; but, unlike most mammals, the end of an infertile cycle is marked by endometrial sloughing and the start of another without an anestrous phase. Women stop cycling at menopause, while in most mammals, cycles continue until death. Epidemiologic studies identified menarche, menopause, births, lactation, and oral contraceptive (OC) use as key risk factors for ovarian, breast, and endometrial cancers. A composite variable was created to estimate the number of cycles not interrupted by events that stop ovulation. Captured by the phrase "incessant ovulation", repetitive cycles were first postulated to affect ovarian cancer risk and later extended to breast and endometrial cancers. These associations could be explained by cumulative effects of repetitive tissue changes within reproductive organs, immune consequences of repetitive ovulation through the glycoprotein mucin 1, and residual effects of past ovulations that enhance ovarian production of testosterone. The latter two pathways could affect the risk for cancers in other organs not considered "reproductive".

Risk of ovarian cancer after salpingectomy and tubal ligation: Prospects on histology and time since the procedure

OBJECTIVE

Recent theories propose that most epithelial ovarian cancer (EOC), depending on histological type, originate from other gynecological tissues and involve the ovary secondarily. According to these theories, any protective effect of salpingectomy and tubal ligation may vary by histological type. The study aim was to examine the association between salpingectomy and tubal ligation, respectively, and risk of EOC, with a focus on associations specific for histological types.

METHODS

We identified EOC cases and matching controls in national registries and gathered information on surgical procedures and potential confounders. Conditional logistic regression was used to estimate odds ratio (OR) with 95% confidence interval (CI) of EOC related to salpingectomy and tubal ligation, respectively, overall and stratified by histological type. Furthermore, we investigated the association according to timing of the procedures.

RESULTS

Our study comprised 16,822 EOC cases. Each case was matched with 40 controls. There was an overall EOC risk reduction after unilateral (OR = 0.73; 95% CI: 0.60-0.87) and bilateral salpingectomy (OR = 0.46; 95% CI: 0.31-0.67). A slight risk reduction was seen among women with previous tubal ligation (OR = 0.91; 95% CI: 0.83-0.99). For salpingectomy, the risk reduction increased with increasing time since the surgical procedure and was only present among women younger than 50 years at salpingectomy. Unilateral and bilateral salpingectomy was associated with a risk reduction for most histological types.

CONCLUSION

The association between previous salpingectomy and reduced risk of several histological subtypes of EOC supports the suggested theories about the site of origin of EOC and may be of clinical importance.

Primary Retroperitoneal Carcinomas: New Insights into Pathogenesis and Clinical Management in Comparison with Ovarian Carcinomas and Carcinoma of Unknown Primary

Primary retroperitoneal carcinomas are very rare tumors. Their pathogenesis remains unknown but may be associated with that of ovarian carcinomas, considering the similarity in morphology and gender preference. Although metaplasia of coelomic epithelium is the most widely accepted theory, the pathogenesis of retroperitoneal carcinomas may differ by histologic subtype, like ovarian carcinomas. Mucinous carcinoma, which develops in both women and men, may originate in both primordial germ cells and Walthard cell nests that may be derived from the fallopian tube. Serous carcinomas may be associated with endosalpingiosis, the presence of fallopian tube-like epithelium outside the fallopian tube, and a remnant Müllerian tract. Endometrioid and clear cell carcinomas appear to be associated with extraovarian endometriosis. Additionally, both carcinomas in the retroperitoneal lymph nodes may be metastatic diseases from endometrial and/or renal cell cancer that regress spontaneously (carcinoma of unknown primary). Retroperitoneal carcinomas are difficult to diagnose, as they have no characteristic symptoms and signs. Surgery is the cornerstone of treatment, but the necessity of chemotherapy may depend on histological subtype. Further studies are necessary, in particular studies on endosalpingiosis, as endosalpingiosis is a poorly understood condition, although it is associated with the development of both serous and mucinous carcinomas.

Reversion of chemoresistance by endocannabinoid-induced ER stress and autophagy activation in ovarian cancer

The difficulty of detection at an early stage and the ease of developing resistance to chemotherapy render ovarian cancer (OVC) difficult to cure. Although several novel cancer therapies have been developed recently, drug resistance remains a concern since chemotherapy remains as the most commonly used treatment for cancer patients. Therefore, there is an urgent need to reclaim potential combination treatments for OVC. So far, there have been several research targeting the endocannabinoid system (ECS) in cancer. Among the various cannabinoid-based drugs, endocannabinoids, which are lipid molecules generated in the body, have been reported to produce many anti-tumor effects; however, research investigating the anti-chemoresistance effect of endocannabinoids in OVC remains unclear. In this study, we aimed to combine endocannabinoids, anandamide (AEA), and 2-arachidonoylglycerol (2-AG) with chemotherapeutic drugs as a combination approach to treat OVC. Our results showed that OVC cells expressed both cannabinoid receptors (CBR), CB1 and CB2, suggesting the possibility of endocannabinoid system (ECS) as a target. We found that the anti-chemoresistance effect mediated by endocannabinoids was caused by upregulation of ceramide levels, leading to severe endoplasmic reticulum (ER) stress and increased autophagy in chemoresistant cancer cells. Therefore, chemoresistant cancer cell growth was inhibited, and cell apoptosis was induced under combined treatments. Based on our results, endocannabinoids overcomed chemoresistance of OVC cells in vitro. Our findings suggest that drugs targeting ECS may have the potential to be adjuvants for chemotherapy by increasing the efficacy of chemotherapeutic drugs and decreasing their side effects.

Associations between prediagnostic aspirin use and ovarian tumor gene expression

BACKGROUND

Aspirin use has been associated with reduced ovarian cancer risk, yet the underlying biological mechanisms are not fully understood. To gain mechanistic insights, we assessed the association between prediagnosis low and regular-dose aspirin use and gene expression profiles in ovarian tumors.

METHODS

RNA sequencing was performed on high-grade serous, poorly differentiated, and high-grade endometrioid ovarian cancer tumors from the Nurses' Health Study (NHS), NHSII, and New England Case-Control Study (n = 92 cases for low, 153 cases for regular-dose aspirin). Linear regression identified differentially expressed genes associated with aspirin use, adjusted for birth decade and cohort. False discovery rates (FDR) were used to account for multiple testing and gene set enrichment analysis was used to identify biological pathways.

RESULTS

No individual genes were significantly differentially expressed in ovarian tumors in low or regular-dose aspirin users accounting for multiple comparisons. However, current versus never use of low-dose aspirin was associated with upregulation of immune pathways (e.g., allograft rejection, FDR = 5.8 × 10-10 ; interferon-gamma response, FDR = 2.0 × 10-4 ) and downregulation of estrogen response pathways (e.g., estrogen response late, FDR = 4.9 × 10-8 ). Ovarian tumors from current regular aspirin users versus never users were also associated with upregulation in interferon pathways (FDR <1.5 × 10-4 ) and downregulation of multiple extracellular matrix (ECM) architecture pathways (e.g., ECM organization, 4.7 × 10-8 ).

CONCLUSION

Our results suggest low and regular-dose aspirin may impair ovarian tumorigenesis in part via enhancing adaptive immune response and decreasing metastatic potential supporting the likely differential effects on ovarian carcinogenesis and progression by dose of aspirin.

Role of LRRN4 in promoting malignant behavior in a p53- and Rb-defective human fallopian tube epithelial cell line

This study explored the role of leucine-rich repeat neuronal 4 (LRRN4) in ovarian carcinogenesis using the p53- and Rb-defective human fallopian tube epithelial cell line FE25. We evaluated the expression of LRRN4 in FE25 cells with and without LRRN4 knockdown by short hairpin RNA (shRNA) and studied its effects on cell proliferation, cell cycle, migration, invasion, chemotherapeutic sensitivity, apoptosis, and xenograft formation. The results showed that FE25 shRNA-LRRN4 cells exhibited more aggressive malignant behaviors than FE25 cells, including faster proliferation and increased cell distribution in the G2/M phase, Akt pathway activation, cell migration, and cell invasion, as well as decreased sensitivity to chemotherapeutic drugs. FE25 shRNA-LRRN4 cells exhibited reduced levels of apoptosis and decreased expression of cleaved caspase 3, 7, 8, and 9, indicating reduced apoptotic activity. Additionally, FE25 shRNA-LRRN4 cells showed decreased LRRN4 and CK7 expression and increased WT1 expression, suggesting a potential role for LRRN4 in ovarian carcinogenesis. FE25 shRNA-LRRN4 generated a xenograft in mice with increased levels of WT1 and TP53 expression compared to their levels in cells. Overall, this study suggests that LRRN4 may play a role in ovarian carcinogenesis by promoting aggressive malignant behavior in FE25 cells through the activation of the Akt pathway. These findings provide insights into the potential molecular mechanisms underlying ovarian cancer and may have implications for the development of new therapeutic targets for this disease.

Temozolomide Sensitizes ARID1A-Mutated Cancers to PARP Inhibitors

ARID1A is a subunit of SWI/SNF chromatin remodeling complexes and is mutated in many types of human cancers, especially those derived from endometrial epithelium, including ovarian and uterine clear cell carcinoma (CCC) and endometrioid carcinoma (EMCA). Loss-of-function mutations in ARID1A alter epigenetic regulation of transcription, cell-cycle checkpoint control, and DNA damage repair. We report here that mammalian cells with ARID1A deficiency harbor accumulated DNA base lesions and increased abasic (AP) sites, products of glycosylase in the first step of base excision repair (BER). ARID1A mutations also delayed recruitment kinetics of BER long-patch repair effectors. Although ARID1A-deficient tumors were not sensitive to monotherapy with DNA-methylating temozolomide (TMZ), the combination of TMZ with PARP inhibitors (PARPi) potently elicited double-strand DNA breaks, replication stress, and replication fork instability in ARID1A-deficient cells. The TMZ and PARPi combination also significantly delayed in vivo growth of ovarian tumor xenografts carrying ARID1A mutations and induced apoptosis and replication stress in xenograft tumors. Together, these findings identified a synthetic lethal strategy to enhance the response of ARID1A-mutated cancers to PARP inhibition, which warrants further experimental exploration and clinical trial validation.

SIGNIFICANCE

The combination of temozolomide and PARP inhibitor exploits the specific DNA damage repair status of ARID1A-inactivated ovarian cancers to suppress tumor growth.

Prevention of Epithelial Ovarian Cancer

Given the challenges with achieving effective and durable treatment for epithelial ovarian cancer, primary prevention is highly desirable. Fortunately, decades of research have provided evidence for several strategies that can be deployed to optimize risk reduction. These include surgery, chemoprevention, and lifestyle factor modifications. These broad categories vary in terms of the magnitude of risk reduction possible, the possible short-term and long-term side effects, the degree of difficulty, and acceptability. Thus, the concept of a risk-based model to personalize preventive interventions is advocated to guide discussion between care providers and women at risk. For women with inherited major gene mutations that greatly increase risk of ovarian cancer, surgical approaches have favorable risk to benefit ratios. Chemoprevention and lifestyle factor modifications portend a lower degree of risk reduction but confer lower risk of undesirable side effects. Since complete prevention is not currently possible, better methods for early detection remain a high priority.

A questionnaire-based survey on the diagnostic and therapeutic approaches for patients with STIC in Germany

PURPOSE

Despite the growing understanding of the carcinogenesis of pelvic high-grade serous carcinoma (HGSC) of the ovary and peritoneum and its precursor lesion serous tubal intraepithelial carcinoma (STIC), evidence-based proven recommendations on the clinical management of patients with STIC are lacking so far.

METHODS

A questionnaire containing 21 questions was developed to explore the clinical experience with patients with the diagnosis of STICs and the diagnostic, surgical and histopathological approaches in Germany. Overall, 540 clinical heads of department in all German gynaecological centres were asked to participate.

RESULTS

131 questionnaires (response rate 24.3%) were included in this survey. 45.8% of the respondents had treated one to three STIC patients during their career. 75.6% of the respondents performed opportunistic bilateral salpingectomies during other gynaecological surgeries. Most of the participants (31.3%) started with the SEE-FIM (Sectioning and Extensively Examining the FIMbria) protocol in 2014. It was requested by 39.7% centres for prophylactic salpingectomies, by 13.7% for both prophylactic and opportunistic salpingectomies and by 22.1% for neither of both. 38.2%, 1.5% and 24.4% of the participants would use the laparoscopic, transverse and midline laparotomic approach for a surgical staging procedure, respectively. 25.6% (54.7%) of the respondents recommended a hysterectomy in premenopausal (versus postmenopausal) patients with a STIC, 24.4% (88.4%) a bilateral oophorectomy and 50.0% (4.7%) an affected side oophorectomy (all p values < 0.001). Omentectomy, pelvic and para-aortic lymphadenectomy would be performed by 60.5% (64.0%), 9.3% (11.6%) and 9.3% (11.6%) of respondents in premenopausal (versus postmenopausal) patients (all p values > 0.05).

CONCLUSION

Our survey highlights significant inconsistency in the management of patients with STIC. Prospective data are urgently needed to elucidate the clinical impact of a STIC lesion and its clinical management.

Ovarian cancer prevention by opportunistic salpingectomy is a new de facto standard in Germany

PURPOSE

The most prevalent and aggressive subtype of epithelial ovarian carcinoma (EOC), high-grade serous carcinoma (HGSC), originates in many cases from the fallopian tubes. Because of poor prognosis and lack of effective screening for early detection, opportunistic salpingectomy (OS) for prevention of EOC is being implemented into clinical routine in several countries worldwide. Taking the opportunity of a gynecological surgery in women at average cancer risk, extramural fallopian tubes are completely resected preserving the ovaries with their infundibulopelvic blood supply. Until recently, only 13 of the 130 national partner societies of the International Federation of Obstetrics and Gynecology (FIGO) have published a statement on OS. This study aimed to analyze the acceptance of OS in Germany.

METHODS

(1) Survey of German gynecologists in 2015 and 2022 by the Department of Gynecology of the Jena University Hospital in co-operation with the Department of Gynecology at Charité-University Medicine Berlin with support of NOGGO e. V. and AGO e. V. (2) Salpingectomy numbers in Germany for years 2005-2020 as retrieved from the Federal Statistical Office of Germany (Destatis).

RESULTS

(1) Survey: Number of participants was 203 in 2015 and 166 in 2022, respectively. Nearly all respondents (2015: 92%, 2022: 98%) have already performed bilateral salpingectomy without oophorectomy in combination with benign hysterectomy with the intention to reduce the risk for malignant (2015: 96%, 2022: 97%) and benign (2015: 47%, 2022: 38%) disorders. Compared to 2015 (56.6%), considerably more survey participants performed OS in > 50% or in all cases in 2022 (89.0%). Recommendation of OS for all women with completed family planning at benign pelvic surgery was approved by 68% in 2015 and 74% in 2022. (2) Case number analysis: In 2020, four times more cases of salpingectomy were reported by German public hospitals compared to 2005 (n = 50,398 vs. n = 12,286). Of all inpatient hysterectomies in German hospitals in 2020, 45% were combined with salpingectomy, and more than 65% in women at the age of 35 to 49 years.

CONCLUSION

Mounting scientific plausibility regarding involvement of fallopian tubes in the pathogenesis of EOC led to change of clinical acceptance of OS in many countries including in Germany. Case number data and widespread expert judgment demonstrate that OS has become a routine procedure in Germany and a de facto standard for primary prevention of EOC.

Executive Summary of the Ovarian Cancer Evidence Review Conference

The Centers for Disease Control and Prevention awarded funding to the American College of Obstetricians and Gynecologists to develop educational materials for clinicians on gynecologic cancers. The American College of Obstetricians and Gynecologists convened a panel of experts in evidence review from the Society for Academic Specialists in General Obstetrics and Gynecology and content experts from the Society of Gynecologic Oncology to review relevant literature, best practices, and existing practice guidelines as a first step toward developing evidence-based educational materials for women's health care clinicians about ovarian cancer. Panel members conducted structured literature reviews, which were then reviewed by other panel members and discussed at a virtual meeting of stakeholder professional and patient advocacy organizations in February 2022. This article is the executive summary of the relevant literature and existing recommendations to guide clinicians in the prevention, early diagnosis, and special considerations of ovarian cancer. Substantive knowledge gaps are noted and summarized to provide guidance for future research.

The Clinical Significance of Genetic Variation in Ovarian Cancer

Genetic variation is a well-known contributor to the onset and progression of cancer. The goal of this study is to provide a comprehensive examination of the nucleotide and chromosomal variation associated with the onset and progression of serous ovarian cancer. Using a variety of computational and statistical methods, we examine the exome sequence profiles of genetic variants present in the primary tumors of 432 ovarian cancer patient samples to compute: (1) the tumor mutational burden for all genes and (2) the chromosomal copy number alterations associated with the onset/progression of ovarian cancer. Tumor mutational burden is reduced in the late vs. early stages, with the highest levels being associated with loss-of-function mutations in DNA-repair genes. Nucleotide variation and copy number alterations associated with known cancer driver genes are selectively favored over ovarian cancer development. The results indicate that genetic variation is a significant contributor to the onset and progression of ovarian cancer. The measurement of the relative levels of genetic variation associated with individual ovarian cancer patient tumors may be a clinically valuable predictor of potential tumor aggressiveness and resistance to chemotherapy. Tumors found to be associated with high levels of genetic variation may help in the clinical identification of high-risk ovarian cancer patients who could benefit from more frequent monitoring.

Effects of Infertility Drug Exposure on the Risk of Borderline Ovarian Tumors: A Systematic Review and Meta-Analysis

Whether infertility drug exposure increases the risk of borderline ovarian tumors (BOTs) remains controversial. The present study was conducted with a comprehensive search for studies published from January 1990 to December 2021 in the online databases Cochrane Library, PubMed, Web of Science and EMBASE. We considered the first diagnosis of a BOT as the primary outcome. The odds ratio (OR) was calculated with corresponding 95% confidence intervals (CIs) for the risk of BOTs in patients who were treated with infertility drugs. Ten studies, a total of 2,779,511 women, qualified for inclusion in this meta-analysis. The pooled OR of 1.56 (95% CI: 1.09-2.22) revealed a significant positive association between infertility drugs and an increased risk for BOTs, but for specific drugs, only CC plus Gn had statistical significance. No publication bias was detected using the Egger and Begg tests (p > 0.05). A significant difference in BOT incidence was observed among infertile women and nulliparous women who were treated with or without infertility drugs. In conclusion, the use of infertility drugs may increase the risk of BOTs, but a dose-dependent relationship was not observed between the number of assisted reproduction technology cycles and the risk of BOTs, and infertile women who successfully became pregnant might have a reduced risk. Registration: PROSPERO, CRD42022330775.

Molecular Status of BRAF Mutation in Epithelial Ovarian Cancer: An Analysis of 57 Cases in the Northeast of Iran

Background & Objective

Epithelial ovarian cancer (EOC) is the most prevalent type of ovarian cancer. Previous studies have elucidated different pathways for the progression of this malignancy. The mutation in the B-Raf proto-oncogene, serine/threonine kinase (BRAF) gene, a member of the MAPK/ERK signaling pathway, plays a role in the development of EOC. The current study aimed to determine the frequency of the BRAF V600E mutation in ovarian serous and mucinous tumors, including borderline and carcinoma subtypes.

Methods

A total of 57 formalin-fixed paraffin-embedded samples, including serous borderline tumors (SBTs), low-grade serous carcinomas (LGSCs), high-grade serous carcinomas (HGSCs), mucinous borderline tumors (MBTs), and mucinous carcinomas, and 57 normal ovarian tissues were collected. The BRAF V600E mutation was analyzed using polymerase chain reaction (PCR) and sequencing.

Results

While 40% of the SBT harbor BRAF mutation, we found no BRAF mutation in the invasive serous carcinoma (P=0.017). Also, there was only 1 BRAF mutation in MBT and no mutation in mucinous carcinomas. In addition, we found no mutation in the control group.

Conclusion

The BRAF mutation is most frequent in borderline tumors but not in invasive serous carcinomas. It seems that 2 different pathways exist for the development of ovarian epithelial neoplasms: one for borderline tumors and the other for high-grade invasive carcinomas. Our study supports this hypothesis. The BRAF mutation is rare in mucinous neoplasms.

Spatial Heterogeneity in Cytoskeletal Mechanics Response to TGF-β1 and Hypoxia Mediates Partial Epithelial-to-Meshenchymal Transition in Epithelial Ovarian Cancer Cells

Metastatic progression of epithelial ovarian cancer (EOC) involves the partial epithelial-to-mesenchymal transition (EMT) of cancer cells in the primary tumor and dissemination into peritoneal fluid. In part to the high degree of heterogeneity in EOC cells, the identification of EMT in highly epithelial cells in response to differences in matrix mechanics, growth factor signaling, and tissue hypoxia is very difficult. We analyzed different degrees of EMT by tracking changes in cell and nuclear morphology, along with the organization of cytoskeletal proteins. In our analysis, we see a small percentage of individual cells that show dramatic response to TGF-β1 and hypoxia treatment. We demonstrate that EOC cells are spatially aware of their surroundings, with a subpopulation of EOC cells at the periphery of a cell cluster in 2D environments exhibited a greater degree of EMT. These peripheral cancer cells underwent partial EMT, displaying a hybrid of mesenchymal and epithelial characteristics, which often included less cortical actin and more perinuclear cytokeratin expression. Collectively, these data show that tumor-promoting microenvironment conditions can mediate invasive cell behavior in a spatially regulated context in a small subpopulation of highly epithelial clustered cancer cells that maintain epithelial characteristics while also acquiring some mesenchymal traits through partial EMT.

MicroRNAs as Potential Biomarkers in Gynecological Cancers

MicroRNAs are non-coding transcripts that, thanks to the ability to regulate the mRNA of target genes, can affect the expression of genes encoding tumor suppressors and oncogenes. They can control many important cellular processes, including apoptosis, differentiation, growth, division, and metabolism. Therefore, miRNAs play an important role in the development of many cancers, including gynecological cancers. Ovarian cancer, endometrial cancer, cervical cancer, and vulvar cancer are the most common cancers in women and are a frequent cause of death. The heterogeneity of the pathogenesis of these gynecological diseases makes the diagnostic process a significant obstacle for modern medicine. To date, many studies have been carried out, in which particular attention has been paid to the molecular pathomechanism of these diseases, with particular emphasis on miRNAs. To date, the changed profile of many miRNAs, which influenced the promotion of proliferation, migration, invasion processes and the simultaneous inhibition of programmed cell death, has been proven many times. Detailed understanding of the molecular effects of miRNAs in the above-mentioned gynecological cancers will enable the development of potential predictive and prognostic biomarkers, as well as the optimization of the diagnostic process.

Crosstalk of Immune Cells and Platelets in an Ovarian Cancer Microenvironment and Their Prognostic Significance

Ovarian cancer (OC) is one of the deadliest gynecological cancers, largely due to the fast development of metastasis and drug resistance. The immune system is a critical component of the OC tumor microenvironment (TME) and immune cells such as T cells, NK cells, and dendritic cells (DC) play a key role in anti-tumor immunity. However, OC tumor cells are well known for evading immune surveillance by modulating the immune response through various mechanisms. Recruiting immune-suppressive cells such as regulatory T cells (Treg cells), macrophages, or myeloid-derived suppressor cells (MDSC) inhibit the anti-tumor immune response and promote the development and progression of OC. Platelets are also involved in immune evasion by interaction with tumor cells or through the secretion of a variety of growth factors and cytokines to promote tumor growth and angiogenesis. In this review, we discuss the role and contribution of immune cells and platelets in TME. Furthermore, we discuss their potential prognostic significance to help in the early detection of OC and to predict disease outcome.

Resveratrol Enhances Cytotoxic Effects of Cisplatin by Inducing Cell Cycle Arrest and Apoptosis in Ovarian Adenocarcinoma SKOV-3 Cells through Activating the p38 MAPK and Suppressing AKT

In the current study, we identified a mechanism of resveratrol (RES) underlying its anti-cancer properties against human ovarian adenocarcinoma SKOV-3 cells. We investigated its anti-proliferative and apoptosis-inducing effects in combination with cisplatin, using cell viability assay, flow cytometry, immunofluorescence study and Western blot analysis. We discovered that RES suppressed cancer cell proliferation and stimulated apoptosis, especially when combined with cisplatin. This compound also inhibited SKOV-3 cell survival, which may partly be due to its potential to inhibit protein kinase B (AKT) phosphorylation and induce the S-phase cell cycle arrest. RES in combination with cisplatin strongly induced cancer cell apoptosis through activating the caspase-dependent cascade, which was associated with its ability to stimulate nuclear phosphorylation of p38 mitogen-activated protein kinase (MAPK), well recognized to be involved in transducing environmental stress signals. RES-induced p38 phosphorylation was very specific, and the activation status of extracellular signal-regulated kinase 1/2 (ERK1/2) and c-Jun N-terminal kinase (JNK) was not mainly affected. Taken together, our study provides accumulated evidence that RES represses proliferation and promotes apoptosis in SKOV-3 ovarian cancer cells through activating the p38 MAPK pathway. It is interesting that this active compound may be used as an effective agent to sensitize ovarian cancer to apoptosis induced by standard chemotherapies.

Tru-Cut Biopsy in Gynecological Cancer: Adequacy, Accuracy, Safety and Clinical Applicability

Purpose

Tru-cut biopsy is a minimally invasive technique used to obtain tissue samples for the diagnosis of tumors, especially in patients where primary surgery is not indicated. The aim of this study was to assess the adequacy, accuracy and safety of the tru-cut biopsy for diagnosis in gynecological cancer.

Methods

A retrospective population-based review of 328 biopsies was conducted. The indications for tru-cut biopsies were diagnosis of primary tumors, metastases of gynecological and non-gynecological tumors, and suspected recurrences. A tissue sample was considered adequate when the quality/quality was sufficient to identify the subtype/origin of the tumor. Potential factors affecting adequacy were analyzed using logistic regressions analyses. Accuracy was defined as agreement between the diagnosis of the tru-cut biopsy and the postoperative histology. The therapy plan was registered, and the clinical applicability of the tru-cut biopsy was investigated. Complications within 30 days after the biopsy procedure were registered.

Results

In total, 300 biopsies were identified as tru-cut biopsies. The overall adequacy was 86.3%, varying between 80.8% and 93.5%, respectively, when performed by a gynecological oncologist or a gynecologist with a subspecialty in ultrasound diagnosis. Sampling of a pelvic mass had a lower adequacy (81.6%) compared with sampling of the omentum (93.9%) or carcinomatosis (91.5%). The accuracy was 97.5%, and the complication rate was 1.3%.

Conclusion

The tru-cut biopsy is a safe and reliable diagnostic method with a high accuracy and a good adequacy, depending on the site of the tissue sample, indications for the biopsy and the experience of the operator.

Lifetime ovulatory years and risk of epithelial ovarian cancer: a multinational pooled analysis

BACKGROUND

The role of ovulation in epithelial ovarian cancer (EOC) is supported by the consistent protective effects of parity and oral contraceptive use. Whether these factors protect through anovulation alone remains unclear. We explored the association between lifetime ovulatory years (LOY) and EOC.

METHODS

LOY was calculated using 12 algorithms. Odds ratios (ORs) and 95% confidence intervals (CIs) estimated the association between LOY or LOY components and EOC among 26 204 control participants and 21 267 case patients from 25 studies. To assess whether LOY components act through ovulation suppression alone, we compared beta coefficients obtained from regression models with expected estimates assuming 1 year of ovulation suppression has the same effect regardless of source.

RESULTS

LOY was associated with increased EOC risk (OR per year increase = 1.014, 95% CI = 1.009 to 1.020 to OR per year increase = 1.044, 95% CI = 1.041 to 1.048). Individual LOY components, except age at menarche, also associated with EOC. The estimated model coefficient for oral contraceptive use and pregnancies were 4.45 times and 12- to 15-fold greater than expected, respectively. LOY was associated with high-grade serous, low-grade serous, endometrioid, and clear cell histotypes (ORs per year increase = 1.054, 1.040, 1.065, and 1.098, respectively) but not mucinous tumors. Estimated coefficients of LOY components were close to expected estimates for high-grade serous but larger than expected for low-grade serous, endometrioid, and clear cell histotypes.

CONCLUSIONS

LOY is positively associated with nonmucinous EOC. Differences between estimated and expected model coefficients for LOY components suggest factors beyond ovulation underlie the associations between LOY components and EOC in general and for non-HGSOC.

Borderline With Bad Behavior: An Unusual Low-grade Serous Carcinoma With Dedifferentiation From a Serous Borderline Tumor

The pathogenesis of serous ovarian tumors has been extensively investigated, with a dualistic model dividing these cancers into 2 groups. Type I tumors, including low-grade serous carcinoma, is characteristic for concurrent presence of borderline tumors, less atypical cytology, relatively indolent biologic behavior, and molecular aberrations related to the MAPK pathway with chromosomal stability. Meanwhile, type II tumors, such as high-grade serous carcinoma, are notable for no significant association with borderline tumors, higher grade cytology, more aggressive biologic behavior, and TP53 mutations along with chromosomal instability. We describe a case of morphologic low-grade serous carcinoma with focally increased cytologic atypia arising in serous borderline tumors involving both ovaries, which demonstrated highly aggressive behavior despite several years of surgical and chemotherapeutic management. Each recurrent specimen contained more uniform higher grade morphology than what was seen in the original specimen. Immunohistochemical and molecular studies in both the original tumor and the most recent recurrence demonstrate identical mutations in the MAPK genes, but with additional mutations in the latter, notably an acquisition of a variant of possible clinical significance in the SMARCA4 gene, which is associated with dedifferentiation and aggressive biologic behavior. This case challenges our current and still evolving understanding of the pathogenesis, biologic behavior, and expected clinical outcome of low-grade serous ovarian carcinomas. It also underscores the need for further investigation into this complicated tumor.

Opportunistic Salpingectomy at the Time of Laparoscopic Cholecystectomy for Ovarian Cancer Prevention: A Cost-effectiveness Analysis

OBJECTIVE

To perform a cost-effectiveness analysis to examine the utility and effectiveness of OS performed at the time of elective cholecystectomy [laparoscopic cholecystectomy (LAP-CHOL)].

SUMMARY BACKGROUND DATA

OS has been adopted as a strategy to reduce the risk of ovarian cancer in women undergoing hysterectomy and tubal sterilization, although the procedure is rarely performed as a risk reducing strategy during other abdominopelvic procedures.

METHODS

A decision model was created to examine women 40, 50, and 60 years of age undergoing LAP-CHOL with or without OS. The lifetime risk of ovarian cancer was assumed to be 1.17%, 1.09%, and 0.92% for women age 40, 50, and 60 years, respectively. OS was estimated to provide a 65% reduction in the risk of ovarian cancer and to require 30 additional minutes of operative time. We estimated the cost, quality-adjusted life-years, ovarian cancer cases and deaths prevented with OS.

RESULTS

The additional cost of OS at LAP-CHOL ranged from $1898 to 1978. In a cohort of 5000 women, OS reduced the number of ovarian cancer cases by 39, 36, and 30 cases and deaths by 12, 14, and 16 in the age 40-, 50-, and 60-year-old cohorts, respectively. OS during LAP-CHOL was cost-effective, with incremental cost-effectiveness ratio of $11,162 to 26,463 in the 3 age models. In a probabilistic sensitivity analysis, incremental cost-effectiveness ratio for OS were less than $100,000 per quality-adjusted life-years in 90.5% or more of 1000 simulations.

CONCLUSIONS

OS at the time of LAP-CHOL may be a cost-effective strategy to prevent ovarian cancer among average risk women.

Genetic analysis for mucinous ovarian carcinoma with infiltrative and expansile invasion and mucinous borderline tumor: a retrospective analysis

BACKGROUND

Mucinous carcinoma (MC) is a histological subtype of ovarian cancer that has a worse prognosis at advanced stages than the most prevalent histological subtype, high-grade serous carcinomas. Invasive patterns have been recognized as prognostic factors for MCs. MCs with infiltrative invasion were more aggressive than those with expansile invasion. MC with an expansile pattern exhibited behavior similar to mucinous borderline tumors (MBT). However, genomic analysis of invasive patterns is insufficient. This study aimed to compare genetic information between groups with MC and infiltrative invasion (Group A) and those with MC with expansile invasion or MBT (Group B).

METHODS

Ten cases each of MC with infiltrative invasion, MC with expansile invasion, and MBT between 2005 and 2020 were identified. Deoxyribonucleic acid (DNA) extraction from formalin-fixed paraffin-embedded tissues was performed, and cases with DNA fragmentation or the possibility of DNA fragmentation were excluded. Mutant base candidates and tumor mutation burden (TMB) values (mutations/megabase) were calculated.

RESULTS

After assessing the quality of purified DNA, seven cases of MC with infiltrative invasion, five cases of MC with expansile invasion, and three cases of MBT were included. More patients in group A experienced recurrence or progression (p < 0.01) and died of disease (p = 0.03). Moreover, the TMB value was statistically higher in group A than in group B (p = 0.049). There were no statistical differences in the incidence of the mutations of KRAS, TP53, and CREBBP. KRAS, TP53, and CREBBP mutations were discovered in 8/15 (53.3%), 6/15 (40.0%), and 5/15 (33.3%) cases, respectively.

CONCLUSIONS

Genetic analysis revealed that Group A had higher TMB than Group B. Therefore, this result might be useful for future treatment.

Positive Rate of Malignant Cells in Endometrial Cytology Samples of Ovarian Cancer, Fallopian Tube Cancer, and Primary Peritoneal Cancer Patients: A Systematic Review and Meta-Analysis

To estimate the feasibility of diagnosing ovarian cancer, fallopian tube cancer, and primary peritoneal cancer through endometrial cytology, we performed a systematic review and meta-analysis to calculate the pooled positive rate of malignant cells in endometrial cytology samples. We queried PubMed, EMBASE, Medline, and Cochrane Central Register of Controlled Trails from inception to November 12, 2020 for studies estimating positive rates of malignant cells in endometrial cytology samples from patients with ovarian cancer, fallopian tube cancer, and primary peritoneal cancer. The positive rates of the included studies were calculated as pooled positive rate through meta-analyses of proportion. Subgroup analysis based on different sampling methods was conducted. Seven retrospective studies involving 975 patients were included. Pooled positive rate of malignant cells in endometrial cytology specimens of ovarian cancer, fallopian tube cancer, and primary peritoneal cancer patients was 23% (95% CI: 16% - 34%). Statistical heterogeneity between the included studies was considerable (I2 = 89%, P < 0.01). The pooled positive rates of the group of brushes and the group of aspiration smears were 13% (95% CI: 10% - 17%, I2 = 0, P = 0.45) and 33% (95% CI: 25% - 42%, I2 = 80%, P < 0.01), respectively. Although endometrial cytology is not an ideal diagnostic tool for ovarian cancer, fallopian tube cancer, and primary peritoneal cancer, it is a convenient, painless, and easy-to-implement adjunct to other tools. Sampling method is one of the factors that affect the detection rate.

Exosomes as crucial emerging tools for intercellular communication with therapeutic potential in ovarian cancer

More than two-thirds of epithelial ovarian cancer (EOC) patients are diagnosed at advanced stages due to the lack of sensitive biomarkers. Currently, exosomes are intensively investigated as non-invasive cancer diagnostic markers. Exosomes are nanovesicles released in the extracellular milieu with the potential to modulate recipient cells' behavior. EOC cells release many altered exosomal cargoes that exhibit clinical relevance to tumor progression. Exosomes represent powerful therapeutic tools (drug carriers or vaccines), posing a promising option in clinical practice for curing EOC in the near future. In this review, we highlight the importance of exosomes in cell–cell communication, epithelial–mesenchymal transition (EMT), and their potential to serve as diagnostic and prognostic factors, particularly in EOC.

Malignant Epithelial Tumors of the Ovary

Epithelial ovarian neoplasms (EON) constitute the majority of ovarian cancers. Among EON, high-grade serous carcinoma (HGSC) is the most common and most likely to present at an advanced stage. Radiologists should recognize the imaging features associated with HGSC, particularly at ultrasound and MR imaging. Computed tomography is used for staging and to direct care pathways. Peritoneal carcinomatosis is common and does not preclude surgical resection. Other less common malignant EON have varied appearances, but share a common correlation between the amount of vascularized solid tissue and the likelihood of malignancy.

The Role of Natural and Semi-Synthetic Compounds in Ovarian Cancer: Updates on Mechanisms of Action, Current Trends and Perspectives

Ovarian cancer represents a major health concern for the female population: there is no obvious cause, it is frequently misdiagnosed, and it is characterized by a poor prognosis. Additionally, patients are inclined to recurrences because of metastasis and poor treatment tolerance. Combining innovative therapeutic techniques with established approaches can aid in improving treatment outcomes. Because of their multi-target actions, long application history, and widespread availability, natural compounds have particular advantages in this connection. Thus, effective therapeutic alternatives with improved patient tolerance hopefully can be identified within the world of natural and nature-derived products. Moreover, natural compounds are generally perceived to have more limited adverse effects on healthy cells or tissues, suggesting their potential role as valid treatment alternatives. In general, the anticancer mechanisms of such molecules are connected to the reduction of cell proliferation and metastasis, autophagy stimulation and improved response to chemotherapeutics. This review aims at discussing the mechanistic insights and possible targets of natural compounds against ovarian cancer, from the perspective of medicinal chemists. In addition, an overview of the pharmacology of natural products studied to date for their potential application towards ovarian cancer models is presented. The chemical aspects as well as available bioactivity data are discussed and commented on, with particular attention to the underlying molecular mechanism(s).

Investigating the suitability of in vitro cell lines as models for the major subtypes of epithelial ovarian cancer

Epithelial ovarian cancer (EOC) is the most fatal gynaecological malignancy, accounting for over 200,000 deaths worldwide per year. EOC is a highly heterogeneous disease, classified into five major histological subtypes-high-grade serous (HGSOC), clear cell (CCOC), endometrioid (ENOC), mucinous (MOC) and low-grade serous (LGSOC) ovarian carcinomas. Classification of EOCs is clinically beneficial, as the various subtypes respond differently to chemotherapy and have distinct prognoses. Cell lines are often used as in vitro models for cancer, allowing researchers to explore pathophysiology in a relatively cheap and easy to manipulate system. However, most studies that make use of EOC cell lines fail to recognize the importance of subtype. Furthermore, the similarity of cell lines to their cognate primary tumors is often ignored. Identification of cell lines with high molecular similarity to primary tumors is needed in order to better guide pre-clinical EOC research and to improve development of targeted therapeutics and diagnostics for each distinctive subtype. This study aims to generate a reference dataset of cell lines representative of the major EOC subtypes. We found that non-negative matrix factorization (NMF) optimally clustered fifty-six cell lines into five groups, putatively corresponding to each of the five EOC subtypes. These clusters validated previous histological groupings, while also classifying other previously unannotated cell lines. We analysed the mutational and copy number landscapes of these lines to investigate whether they harboured the characteristic genomic alterations of each subtype. Finally we compared the gene expression profiles of cell lines with 93 primary tumor samples stratified by subtype, to identify lines with the highest molecular similarity to HGSOC, CCOC, ENOC, and MOC. In summary, we examined the molecular features of both EOC cell lines and primary tumors of multiple subtypes. We recommend a reference set of cell lines most suited to represent four different subtypes of EOC for both in silico and in vitro studies. We also identify lines displaying poor overall molecular similarity to EOC tumors, which we argue should be avoided in pre-clinical studies. Ultimately, our work emphasizes the importance of choosing suitable cell line models to maximise clinical relevance of experiments.

Current and emerging biomarkers in ovarian cancer diagnosis; CA125 and beyond

Ovarian cancer (OC) is one of the most common causes of cancer-related death in women worldwide. Its five-year survival rates are worse than the two most common gynecological cancers, cervical and endometrial. This is because it is asymptomatic in the early stages and usually detected in the advanced metastasized stage. Thus, survival is increasingly dependent on timely diagnosis. The delay in detection is contributed partly by the occurrence of non-specific clinical symptoms in the early stages and the lack of effective biomarkers and detection approaches. This underlines the need for biomarker identification and clinical validation, enabling earlier diagnosis, effective prognosis, and response to therapy. Apart from the traditional diagnostic biomarkers for OC, several new biomarkers have been delineated using advanced high-throughput molecular approaches in recent years. They are currently being clinically evaluated for their true diagnostic potential. In this chapter, we document the commonly utilized traditional screening markers and recently identified emerging biomarkers in OC diagnosis, focusing on secretory and protein biomarkers. We also briefly reviewed the recent advances and prospects in OC diagnosis.

Molecular Histopathology for Establishing Diagnostic Method and Clinical Therapy for Ovarian Carcinoma

Ovarian carcinoma (OC) is considered the deadliest gynecological malignancy. It is typically diagnosed in the advanced stages of the disease, with metastatic sites widely disseminated within the abdominal cavity. OC treatment is challenging due to the high rate of disease recurrence, which is further complicated by acquired chemoresistance caused by the reversion of the pathological variant. Therefore, more effective treatments are still being sought. Histologically, OC is classified into serous, mucinous, endometrioid, clear cell, and transitional cell carcinomas and malignant Brenner tumor. Recent clinicopathological and molecular biological studies demonstrated that these subtypes differ in histogenesis and anti-tumor agent sensitivity. In Japan, the incidence rates of the histological types of OC, namely, serous carcinoma, mucinous carcinoma, endometrioid carcinoma, and clear cell adenocarcinoma, are 39%, 12%, 16%, and 23%, respectively. Serous carcinoma is classified as high or low grade, with the former accounting for the overwhelming majority. In this study, the molecular pathological classification of OC has been described based on the characteristics of the two types of OC, types 1 and 2. Compared with Europe and the United States, Japan has a higher prevalence of type 1 OC and a lower prevalence of type 2 OC. The prevalence of each type of OC varies by race. It has been elucidated that the prevalence rate of each type of ovarian cancer in Asian countries is similar to that in Japan. Thus, OC is a heterogeneous disease. Furthermore, OC has been attributed to molecular biological mechanisms that vary among tissue subtypes. Therefore, it is necessary to conduct treatment based on accurate diagnoses of each tissue type and establish an optimal treatment strategy, and now is the transition period.

Familial risk of epithelial ovarian cancer after accounting for gynaecological surgery: a population-based study

BACKGROUND

Uptake of risk-reducing surgery has increased among women at high risk of epithelial ovarian cancer. We sought to characterise familial risk of epithelial ovarian cancer histotypes in a population-based study after accounting for gynaecological surgeries, including bilateral oophorectomy.

METHODS

We compared risk of epithelial ovarian cancer in relatives of 3536 epithelial ovarian cancer cases diagnosed in 1966-2016 and relatives of 35 326 matched controls. We used Cox competing risk models, incorporating bilateral oophorectomy as a competing risk, to estimate the relative risk of ovarian cancer in first-degree (FDR), second-degree (SDR) and third-degree (TDR) relatives from 1966 to 2016. We also estimated relative risks in time periods before (1966-1994, 1995-2004) and after (2005-2016) formal recommendations were made for prophylactic oophorectomy among women with pathogenic variants in BRCA1/2.

RESULTS

The relative risks of epithelial ovarian cancer in FDRs, SDRs and TDRs of cases versus controls were 1.68 (95% CI 1.39 to 2.04), 1.51 (95% CI 1.30 to 1.75) and 1.34 (95% CI 1.20 to 1.48), respectively. Relative risks were greatest for high-grade serous, mucinous and 'other epithelial' histotypes. Relative risks were attenuated for case FDRs, but not for SDRs or TDRs, from 2005 onwards, consistent with the timing of recommendations for prophylactic surgery.

CONCLUSION

Familial risk of epithelial ovarian cancer extends to TDRs, especially for high-grade serous and mucinous histotypes. Distant relatives share genes but minimal environment, highlighting the importance of germline inherited genetics in ovarian cancer aetiology. Increased ovarian cancer risk in distant relatives has implications for counselling and recommendations for prophylactic surgeries that, from our data, appear only to reach FDRs.

Prognostic significance and risk factors for pelvic and para-aortic lymph node metastasis in type I and type II ovarian cancer: a large population-based database analysis

BACKGROUND

To compare the prognosis of lymphatic metastasis in type I and type II epithelial ovarian cancer (OC) and to identify the risk factors for pelvic lymph node metastases (PLNs) and para-aortic lymph node metastases (PALNs).

METHODS

Patients diagnosed with epithelial OC were collected from the Surveillance, Epidemiology, and End Results (SEER) database. Overall survival (OS) and cancer-specific survival (CSS) were estimated. The Cox proportional hazards regression model was used to identify independent predictors of survival.

RESULTS

A total of 11,275 patients with OC were enrolled, including 31.2% with type I and 68.8% with type II. Type II and high tumour stage were risk factors for lymph node involvement (p < 0.05). The overall rate of lymph node metastasis in type I was 11.8%, and that in type II was 36.7%. In the type I group, the lymph node metastasis rates in stages T1, T2, T3 and T_XM₁ were 3.2%, 14.5%, 40.4% and 50.0%, respectively. In the type II group, these rates were 6.4%, 20.4%, 54.1% and 61.1%, respectively. Age and tumour size had little effect on lymph node metastasis, and grade 3 was not always a risk factor. For the type I group, the 10-year CSS rates of LN(-), PLN( +), PALN( +), and PLN + PALN( +) were 80.6%, 46.6%, 36.3%, and 32.3%, respectively. The prognosis of PLN ( +) was better than that of PALN ( +) in the type I group (p > 0.05). For the type II group, the 10-year CSS rates of LN(-), PLN( +), PALN( +), and PLN + PALN( +) were 55.6%, 18.5%, 25.7%, and 18.2%, respectively. PALN ( +) had a significantly better prognosis than PLN ( +) in the type II group (p < 0.05).

CONCLUSIONS

The clinical characteristics and prognoses of patients with type I and type II OC differed greatly. Patients with type II and higher tumour stages had poorer prognoses. Type I with PALN metastasis and type II with PLN metastasis indicated a worse prognosis. Patients with stage TI did not require lymph node dissection, especially in the type I group.

Predictors of residual disease after debulking surgery in advanced stage ovarian cancer

Objective

Optimal debulking with no macroscopic residual disease strongly predicts ovarian cancer survival. The ability to predict likelihood of optimal debulking, which may be partially dependent on tumor biology, could inform clinical decision-making regarding use of neoadjuvant chemotherapy. Thus, we developed a prediction model including epidemiological factors and tumor markers of residual disease after primary debulking surgery.

Methods

Univariate analyses examined associations of 11 pre-diagnosis epidemiologic factors (n=593) and 24 tumor markers (n=204) with debulking status among incident, high-stage, epithelial ovarian cancer cases from the Nurses' Health Studies and New England Case Control study. We used Bayesian model averaging (BMA) to develop prediction models of optimal debulking with 5x5-fold cross-validation and calculated the area under the curve (AUC).

Results

Current aspirin use was associated with lower odds of optimal debulking compared to never use (OR=0.52, 95%CI=0.31-0.86) and two tissue markers, ADRB2 (OR=2.21, 95%CI=1.23-4.41) and FAP (OR=1.91, 95%CI=1.24-3.05) were associated with increased odds of optimal debulking. The BMA selected aspirin, parity, and menopausal status as the epidemiologic/clinical predictors with the posterior effect probability ≥20%. While the prediction model with epidemiologic/clinical predictors had low performance (average AUC=0.49), the model adding tissue biomarkers showed improved, but weak, performance (average AUC=0.62).

Conclusions

Addition of ovarian tumor tissue markers to our multivariable prediction models based on epidemiologic/clinical data slightly improved the model performance, suggesting debulking status may be in part driven by tumor characteristics. Larger studies are warranted to identify those at high risk of poor surgical outcomes informing personalized treatment.

LACTB exerts tumor suppressor properties in epithelial ovarian cancer through regulation of Slug

Epithelial-mesenchymal transition (EMT) is a cellular mechanism used by cancer cells to acquire migratory and stemness properties. In this study, we show, through in vitro, in vivo, and 3D culture experiments, that the mitochondrial protein LACTB manifests tumor suppressor properties in ovarian cancer. We show that LACTB is significantly down-regulated in epithelial ovarian cancer cells and clinical tissues. Re-expression of LACTB negatively effects the growth of cancer cells but not of non-tumorigenic cells. Mechanistically, we show that LACTB leads to differentiation of ovarian cancer cells and loss of their stemness properties, which is achieved through the inhibition of the EMT program and the LACTB-dependent down-regulation of Snail2/Slug transcription factor. This study uncovers a novel role of LACTB in ovarian cancer and proposes new ways of counteracting the oncogenic EMT program in this model system.

Fallopian tubal histogenesis of ovarian endometriosis-A study of folate receptor-alpha expression

Background

Ovary is a common organ site involved by endometriosis. We previously found that fallopian tube may contribute to the histogenesis of ovarian endometriosis. The finding was novel and requires further studies. We addressed this issue by examining a differentially expressed gene folate receptor alpha (FOLR1) and its protein (FRA) in this study.

Results

A total of 144 tissue samples were studied. These included 32-paired tubal-endometrial-ovarian endometriosis samples (n = 96), 18 samples of ovarian endometriosis without corresponding fallopian tube or endometrium, and 30 ovarian tissue samples with ovarian surface epithelia but without endometriosis. Multiple comparisons among groups of ovarian endometriosis, normal fallopian tube and benign endometrium were performed. FOLR1 was highly expressed in the epithelia of fallopian tube and ovarian endometriosis, with paired endometrial samples showing a significantly lower level of expression. Similar differential studies for FRA protein were performed through Western blot and immunohistochemistry (IHC). The expression of folate receptor alpha at both mRNA and protein levels in the tissues (fallopian tube or ovarian endometriosis vs. the endometrium) were significantly different (p < 0.001). All ovarian surface mesothelial epithelia showed negative expression of FRA by IHC.

Conclusion

The results further support that the fallopian tube may contribute to the development of ovarian endometriosis. Understanding the tubal contribution to ovarian endometriosis should ultimately contribute to ongoing investigative efforts aimed at identifying alternative ways to prevent and treat endometriosis. High level of FRA expression in the fallopian tube and endometriosis might be considered as potential tissue sites for targeted therapy.

Berberine enhances the sensitivity of radiotherapy in ovarian cancer cell line (SKOV-3)

Berberine, a well-known isoquinoline alkaloid derivative, has a varied range of pharmacological effects. Herein, we notice the radio-modulatory outcome of berberine in cultured ovarian cancer (SKOV-3) cells exposed to γ-rays as radiotherapy (RT). Cells pre-treated with berberine were irradiated by γ-irradiation and the liberation of reactive oxygen species (ROS) was analyzed by flow cytometry. Apoptotic cell death along with the DNA damage associated with protein expressions was projected by flow cytometry and confocal microscopy. Experimental findings established that berberine might be a capable radiosensitizer for treating SKOV-3, because of oxidative DNA damage. Moreover, the in-silico study of the compound, berberine suggests free energy of binding (ΔG) -7.5 kcal/mol with SKOV-3 and -8.8 kcal/mol of PALB/BRCA2, which proves an effective and compact binding of the complex and is safe for future clinical trials. Thus, our approach is probably to widen the field of study of SKOV-3 and PALB/BRCA2 from the inhibition of these targets as a prospective nutraceutical for the anti-cancer theragnostic candidate.

Review the progression of ovarian clear cell carcinoma from the perspective of genomics and epigenomics

Ovarian clear cell carcinoma (OCCC) is a rare subtype of epithelial ovarian cancer with unique molecular characteristics, specific biological and clinical behavior, poor prognosis and high resistance to chemotherapy. Pushed by the development of genome-wide technologies, our knowledge about the molecular features of OCCC has been considerably advanced. Numerous studies are emerging as groundbreaking, and many of them are promising treatment strategies. In this article, we reviewed studies about the genomics and epigenetics of OCCC, including gene mutation, copy number variations, DNA methylation and histone modifications.

Role of γδ T Cells in Cancer Progression and Therapy

γδ T cells signify a foundational group of immune cells that infiltrate tumors early on, engaging in combat against cancer cells. The buildup of γδ T cells as cancer advances underscores their significance. Initially, these cells infiltrate and enact cytotoxic effects within the tumor tissue. However, in later stages, the predominant phenotype of γδ T cells undergoes changes in numerous cancers, fostering tumor growth and metastasis. Different mechanisms induced by cancer cell suppress effector action of γδ T cells and even sometimes promote cancer progression. In the early stages, stopping this mechanism clears this challenge and enables γδ T cells to effectively remove cancer cells. Given this context, it becomes imperative to delve into the mechanisms of how γδ T cells function in tumor microenvironment. This review discusses γδ T cells' role across different cancer types.

Nanotechnology-Based Nucleic Acid Vaccines for Treatment of Ovarian Cancer

Anticancer vaccines represent a promising approach for effective treatment of cancer and along with recent advantages of nucleic acid-based vaccines for other diseases form a prospective and potentially efficacious direction of the research, development and clinical applications. Despite the ongoing several clinical trials of mRNA vaccines for the treatment of various types of cancer, to-date no cancer vaccines were approved by the US Food and Drug Administration. The present review analyzes and summarizes major approaches for treating of different forms of ovarian cancer including mRNA-based vaccines as well as nanotechnology-based approaches for their delivery.

Thoracic spinal metastasis as recurrence of borderline Brenner tumor without local recurrence: A case report

Background

Brenner tumor is a rare epithelial ovarian neoplasm that accounts for 2-3% of all ovarian neoplasms. Herein, we report the first case of thoracic spinal metastasis of recurrent Brenner tumor without local recurrence.Case Description.A 70-year-old female presented with a feeling of abdominal distension. Computed tomography revealed cystic lesions in her bilateral ovaries. Blood examination revealed high CA-125 [74.9 U/ml]. We excised bilateral ovaries, uterus, and omentum. Borderline Brenner tumor was diagnosed [Ki-67 labeling index: 10 %]. Follow-up abdominal echo and CA-125 examination revealed no local recurrence. 26 months later she developed paraplegia. Magnetic resonance imaging revealed tumor in the 5th-9th thoracic vertebra and compression of spinal cord at the 6th thoracic vertebra level. Her paraplegia was progressive. We performed semi-urgent partial resection of tumor and release of spinal cord compression. Spinal metastasis from Brenner tumor was diagnosed [Ki-67 labeling index: 50-60 %]. She received adjuvant radiation of 30 Gy in 10 fractions to the 4th-10th thoracic vertebra. After radiation and rehabilitation, she was discharged home on foot. She received adjuvant radiation and chemotherapy but died 11 months after spinal surgery. An autopsy has not been performed on her, and the cause of death is unknown.

Conclusion

We report the first case of thoracic metastasis of recurrent Brenner tumor without local recurrence.