The cell of origin of ovarian epithelial tumours

Current Science and Practice of Surgical and Nonsurgical Opportunities for Ovarian Cancer Prevention

Due to improved understanding of ovarian cancer pathogenesis, we have an unprecedented chance to decrease the burden of disease by maximizing opportunities for prevention. Innovations in surgical options for prevention stem from the discovery that many cases directly or indirectly arise from the fallopian tube. Surgical prevention with salpingectomy alone decreases risk by ≥50%. Effective hormonal and nonhormonal chemopreventive agents are also available. Risk stratification is key to ensuring that options for prevention are appropriately matched to individual risk profile. This evidence-based review provides a critical appraisal of the translational health research endeavors supporting ovarian cancer prevention in clinical practice.

Risk-reducing salpingectomy with delayed oophorectomy to prevent ovarian cancer in women with an increased inherited risk: insights into an alternative strategy

Epithelial ovarian cancer (EOC) is the most lethal type of gynaecological cancer, due to lack of effective screening possibilities and because the disease tends to metastasize before onset of symptoms. Women with an increased inherited risk for EOC are advised to undergo a risk-reducing salpingo-oophorectomy (RRSO), which decreases their EOC risk by 96% when performed within guideline ages. However, it also induces premature menopause, which has harmful consequences. There is compelling evidence that the majority of EOCs originate in the fallopian tube. Therefore, a risk-reducing salpingectomy with delayed oophorectomy (RRS with DO) has gained interest as an alternative strategy. Previous studies have shown that this alternative strategy has a positive effect on menopause-related quality of life and sexual health when compared to the standard RRSO. It is hypothesized that the alternative strategy is non-inferior to the standard RRSO with respect to oncological safety (EOC incidence). Three prospective studies are currently including patients to compare the safety and/or quality of life of the two distinct strategies. In this article we discuss the background, opportunities, and challenges of the current and alternative strategy.

Pathophysiology and Clinical Implications of Ovarian Endometriomas

Ovarian endometriomas affect many patients with endometriosis and have significant effects on quality of life, fertility, and risk of malignancy. Endometriomas range from small (1-3 cm), densely fibrotic cysts to large (20 cm or greater) cysts with varying degrees of fibrosis. Endometriomas are hypothesized to form from endometriotic invasion or metaplasia of functional cysts or alternatively from ovarian surface endometriosis that bleeds into the ovarian cortex. Different mechanisms of endometrioma formation may help explain the phenotypic variability observed among endometriomas. Laparoscopic surgery is the preferred first-line modality of diagnosis and treatment of endometriomas. Ovarian cystectomy is preferred over cyst ablation or sclerotherapy for enabling pathologic diagnosis, improving symptoms, preventing recurrence, and optimizing fertility outcomes. Cystectomy for small, densely adherent endometriomas is made challenging by dense fibrosis of the cyst capsule obliterating the plane with normal ovarian cortex, whereas cystectomy for large endometriomas can carry unique challenges as a result of adhesions between the cyst and pelvic structures. Preoperative and postoperative hormonal suppression can improve operative outcomes and decrease the risk of endometrioma recurrence. Whether the optimal management, fertility consequences, and malignant potential of endometriomas vary on the basis of size and phenotype remains to be fully explored.

Cell State of Origin Impacts Development of Distinct Endometriosis-Related Ovarian Carcinoma Histotypes

Clear cell ovarian carcinoma (CCOC) and endometrioid ovarian carcinoma (ENOC) are ovarian carcinoma histotypes, which are both thought to arise from ectopic endometrial (or endometrial-like) cells through an endometriosis intermediate. How the same cell type of origin gives rise to two morphologically and biologically different histotypes has been perplexing, particularly given that recurrent genetic mutations are common to both and present in nonmalignant precursors. We used RNA transcription analysis to show that the expression profiles of CCOC and ENOC resemble those of normal endometrium at secretory and proliferative phases of the menstrual cycle, respectively. DNA methylation at the promoter of the estrogen receptor (ER) gene (ESR1) was enriched in CCOC, which could potentially lock the cells in the secretory state. Compared with normal secretory-type endometrium, CCOC was further defined by increased expression of cysteine and glutathione synthesis pathway genes and downregulation of the iron antiporter, suggesting iron addiction and highlighting ferroptosis as a potential therapeutic target. Overall, these findings suggest that while CCOC and ENOC arise from the same cell type, these histotypes likely originate from different cell states. This "cell state of origin" model may help to explain the presence of histologic and molecular cancer subtypes arising in other organs.

SIGNIFICANCE

Two cancer histotypes diverge from a common cell of origin epigenetically locked in different cell states, highlighting the importance of considering cell state to better understand the cell of origin of cancer.

Recurrent mucinous cystic neoplasm of the mesentery in a young nullipara mimicking as ovarian carcinoma

INRODUCTION

Mucinous cystic neoplasms are rare tumors. They may originate from either ovaries, pancreas, or other intra-abdominal sites, but rarely from the mesentery.

CASE HISTORY

A 22-year-old nulliparaous woman, who had undergone laparascopic bilateral cystectomy for recurrent ovarian mass, presented with pain in abdomen, backache, and menstrual irregularities. Provisionally diagnosed as ovarian carcinoma, she underwent bilateral salpingo-oophorectomy and sigmoid colectomy. However, the histopathological examination revealed mucinous cystic neoplasm of the mesentery.

DISCUSSION

Thus, complete resection of the cysts with meticulous gross and histopathological examination remains the gold standard to differentiate mucinous cystic neoplasm (MCN) of the mesentery from its mimics, especially malignant counterparts, enabling clinicians to adequately manage such patients. Here, we present a case of recurrent MCN of mesentery (mesocolon), mimicking as ovarian carcinoma confirmed on histopathological examination, in a young adult.

Primary Peritoneal Carcinosarcoma in a Breast Cancer Patient Harboring a Germline BRCA2 Pathogenic Variant: Case Report

Malignant mixed müllerian tumor (MMMT) is a rare neoplasm, consisting of carcinomatous (epithelial) and sarcomatous (mesenchymal) components that most commonly arise in the endometrium and more infrequently in the ovaries, fallopian tube, cervix, and vagina. Primary peritoneal carcinosarcoma (PPCS) is an extremely rare extragenital presentation of MMMT. Although the occurrence of breast cancer and epithelial ovarian carcinoma in association with BRCA pathogenic variants is firmly established, the etiologic role of these genes in the development of other tumor types is less well known. Here, we present a rare case of PPCS in a 42-year-old Brazilian woman with a BRCA2 pathogenic variant, c.2808_2811del (NM_000059.3). The patient developed metastatic breast cancer at the age of 37 and underwent a risk-reducing bilateral salpingo-oophorectomy 2 years later. She was then diagnosed with PPCS 3 years after the risk-reducing surgery. She underwent treatment with surgery, chemotherapy, and targeted therapy but passed away almost 5 years after the second primary tumor diagnosis. To our knowledge, this is the first case of peritoneal carcinosarcoma described in a BRCA2 pathogenic variant carrier, and its report leads to a better understanding of the disease's molecular features and possible therapeutic approaches.

The research progress on synchronous endometrial and ovarian carcinoma

Synchronous endometrial and ovarian carcinoma (SEOC) is the most common combination of primary double cancer in the female reproductive system. The etiology and pathogenesis of SEOC remain unclear, and clinically, it is often misdiagnosed as metastatic cancer, affecting the formulation of treatment plans and prognosis for patients. This article provides a review of its epidemiology, pathological and clinical characteristics, risk factors, pathogenesis, diagnosis, treatment, and prognosis.

Polymeric immunoglobulin receptor (pIgR) in cancer

BACKGROUND

The polymeric immunoglobulin receptor (pIgR) is a transmembrane transporter of polymeric IgA through the intestinal epithelium. Its overexpression has been reported in several cancers, but its role as a diagnostic and prognostic biomarker of oncogenesis is currently unclear.

METHOD

A literature search was conducted to summarize the functions of pIgR, its expression levels, and its clinical implications.

RESULTS

pIgR expression has previously been investigated by proteomic analysis, RNA sequencing, and tissue microarray at the level of both RNA and protein in various cancers including pancreatic, esophageal, gastric, lung, and liver. However, studies have reported inconsistent results on how pIgR levels affect clinical outcomes such as survival rate and chemotherapy resistance. Possible explanations include pIgR mRNA levels being minimally correlated with the rate of downstream pIgR protein synthesis, and the diversity of antibodies used in immunohistochemistry studies further magnifying this ambiguity. In ovarian cancer cells, the transcytosis of IgA accompanied a series of transcriptional changes in intracellular inflammatory pathways that inhibit the progression of cancer, including the upregulation of IFN-gamma and downregulation of tumor-promoting ephrins. These findings suggest that both the levels of pIgR and secreted IgA from tumor-infiltrating B cells affect clinical outcomes.

CONCLUSION

Overall, no direct correlation was observed between the levels of pIgR inside tumor tissue and the clinical features in cancer patients. Measuring pIgR protein levels with a more specific and possibly chemically defined antibody, along with tumoral IgA, is a potential solution to better understand the pathways and consequences of pIgR overexpression in cancer cells.

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.

Interaction between membranous EBP50 and myosin 9 as a favorable prognostic factor in ovarian clear cell carcinoma

Ezrin-radixin-moesin-binding phosphoprotein 50 (EBP50) is a scaffold protein that is required for epithelial polarity. Knockout (KO) of membranous EBP50 (Me-EBP50) in ovarian clear cell carcinoma (OCCC) cells induced an epithelial-mesenchymal transition (EMT)-like phenotype, along with decreased proliferation, accelerated migration capability, and induction of cancer stem cell (CSC)-like properties. Shotgun proteomics analysis of proteins that co-immunoprecipitated with EBP50 revealed that Me-EBP50 strongly interacts with myosin 9 (MYH9). Specific inhibition of MYH9 with blebbistatin phenocopied Me-EBP50 KO, and blebbistatin treatment potentiated the effects of Me-EBP50 KO. In OCCC cells from clinical samples, Me-EBP50 and MYH9 were co-localized at the apical plasma membrane. Patients with a combination of Me-EBP50-high and MYH9-high scores had the best prognosis for overall and progression-free survival. Our data suggest that Me-EBP50 has tumor-suppressive effects through the establishment and maintenance of epithelial polarization. By contrast, loss of Me-EBP50 expression induces EMT-like phenotypes, probably due to MYH9 dysfunction; this results in increased cell mobility and enhanced CSC-like properties, which in turn promote OCCC progression.

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.

Exosomes derived from ovarian cancer cells regulate proliferation and migration of cancer-associated fibroblasts

Cancer-associated fibroblast (CAF) is an essential risk factor for ovarian cancer. Exosomes can mediate cellular communication in the tumour microenvironment, but the interaction of tumour cell exosomes with CAF is less studied in Ovarian cancer. This study identified H19/miR-29c-3p/LOXL2-COL1A1 as a ceRNA regulatory network involved in regulating tumour matrix-associated signaling pathways associated with CAF. Cellular assays demonstrated that exosomes from ovarian cancer cell line SKOV3 significantly promoted the proliferation and migration of CAF. The results of mixed transplantation tumour experiments in nude mice showed that exosomes of SKOV3 significantly promoted tumour growth. Ovarian cancer tumour-derived exosomes can regulate CAF proliferation and migration through H19/miR-29c-3p/LOXL2-COL1A1. This study reveals the regulatory role of tumour exosomes on CAF, which may provide a theoretical basis for the development of therapeutic regimens targeting fibroblasts in ovarian cancer.

A Decade of Therapeutic Challenges in Synchronous Gynecological Cancers from the Bucharest Oncological Institute

The aim of our study is to present the particularities of a specific subset of gynecological cancer patients in Romania. We present a review of synchronous gynecological neoplasia (SGN) treated in the Bucharest Oncological Institute's surgery departments over a decade. Between 2012 and 2022, 7419 female patients with genital malignancies were treated. We identified 36 patients with invasive synchronous primary gynecological cancers (0.5%) and 12 cases with one primary gynecological and another primary invasive pelvic cancer (rectal/bladder). All recurrent, metastatic, or metachronous tumors detected were excluded. Demographic data, personal history, presenting symptoms, pathologic findings, staging, treatment, and evolution for each case were recorded. Usually, the most common SGN association is between ovarian and endometrial cancer of endometrioid differentiation (low-grade malignancies with very good prognosis). However, we noticed that, given the particularities of the Romanian medical system, the most frequent association is between cervical and endometrial, followed by cervical and ovarian cancers. Moreover, the cancer stage at diagnosis is more advanced. In countries with low HPV vaccination rate and low adherence to screening programs, SGNs can present as extremely advanced cases and require extensive surgery (such as pelvic exenterations) to achieve radicality. This multimodal treatment in advanced cases with high tumor burden determines a reduction in survival, time until progression, and quality of life.

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.

Assessing the risk of cervical neoplasia in the post-HPV vaccination era

This review is based on the recent EUROGIN scientific session: "Assessing risk of cervical cancer in the post-vaccination era," which addressed the demands of cervical intraepithelial neoplasia (CIN)/squamous intraepithelial lesion (SIL) triage now that the prevalence of vaccine-targeted oncogenic high-risk (hr) human papillomaviruses (HPVs) is decreasing. Change in the prevalence distribution of oncogenic HPV types that follows national HPV vaccination programs is setting the stage for loss of positive predictive value of conventional but possibly also new triage modalities. Understanding the contribution of the latter, most notably hypermethylation of cellular and viral genes in a new setting where most oncogenic HPV types are no longer present, requires studies on their performance in vaccinated women with CIN/SIL that are associated with nonvaccine HPV types. Lessons learned from this research may highlight the potential of cervical cells for risk prediction of all women's cancers.

Poor-prognosis molecular subtypes in adenocarcinomas of pancreato-biliary and gynecological origin: A systematic review

Pancreato-biliary and gynecological adenocarcinomas need better tools to predict clinical outcome. Potential prognostic mesenchymal(-like) transcriptome-based subtypes have been identified in these cancers. In this systematic review, we include studies into molecular subtyping and summarize biological and clinical features of the subtypes within and across sites of origin, searching for suggestions to improve classification and prognostication. PubMed and Embase were searched for original research articles describing potential mesenchymal(-like) mRNA-based subtypes in pancreato-biliary or gynecological adenocarcinomas. Studies limited to supervised clustering were excluded. Fourty-four studies, discussing cholangiocarcinomas, gallbladder, ampullary, pancreatic, ovarian, and endometrial adenocarcinomas were included. There was overlap in molecular and clinical features in mesenchymal(-like) subtypes across all adenocarcinomas. Approaches including microdissection were more likely to identify prognosis-associating subtypes. To conclude, molecular subtypes in pancreato-biliary and gynecological adenocarcinomas share biological and clinical characteristics. Furthermore, separation of stromal and epithelial signals should be applied in future studies into biliary and gynecological adenocarcinomas.

Immunohistochemical Expression of LHRH Receptor in Different Compartments of Female Genital Tract in Patients With Endometrial Cancer

Luteinizing hormone-releasing hormone receptor (LHRHR) expression has been reported in various cancers, including endometrial neoplasms. Thus, LHRHR provides a potential point for therapeutic approach using LHRH analogs as carrier molecules for chemotherapeutic agents in this cancer population. However, clinical data did not prove any potential benefits for patients. We decided to assess LHRHR expression in patients with endometrial cancer to explain possible lack of efficacy in previous clinical reports. LHRHR expression was assessed immunohistochemically in different anatomic and histogenetic compartments of female genital tract of patients with endometrial cancer. The study sample consisted of paraffin tissue blocks obtained from patients who has undergone primary surgery owing to endometrial cancer. Strong LHRHR expression was found in endometrial cancer, fallopian tube, and concurrent atypical hyperplasia. Interestingly, LHRHR expression showed significant differences depending on the respective compartment of the ovary analyzed. Level of LHRHR expression in patients with primary advanced and unresectable disease, particularly in certain ovarian compartments may be substantially lower, which may influence the use of new targeted therapy regimens. The studies on secondary Müllerian system compartment and its hormonal receptor status may be crucial to understand mechanisms of lack of efficacy of LHRH hybrid molecules anti-cancer treatment.

Incidence of other cancer diagnoses in women with breast cancer: a retrospective cohort study with 42,248 women

PURPOSE

The aim of the present study was to determine whether women diagnosed with breast cancer (BC) have an increased incidence of other cancers, e.g., gastric cancer, lung cancer, skin cancer, and so on, compared to healthy women without a breast cancer diagnosis.

METHODS

This retrospective cohort study was based on data from the Disease Analyzer database (IQVIA) and included adult women with an initial diagnosis of BC documented in one of 1,274 general practices in Germany between January 2000 and December 2018. Women with BC were matched to women without cancer by age, index year, yearly consultation frequency, and co-diagnoses. Univariate Cox regression models were used to study the association between BC and the incidence of other cancer diagnoses.

RESULTS

21,124 women with BC and 21,124 women (mean age: 63 years) without cancer were included. Within 10 years of the index date, 14.3% of women with BC and 10.0% of women without cancer were diagnosed with cancer (p < 0.001). BC was significantly associated with the incidence of other cancer diagnoses (HR: 1.42, p < 0.001). The strongest association was observed for respiratory organ cancer (HR = 1.69, p < 0.001), followed by female genital organ cancer (HR = 1.61, p < 0.001) and cancer of lymphoid and hematopoietic tissue (HR: 1.59, p < 0.001).

CONCLUSION

The results of this study show that women with BC have an increased incidence of another cancer compared to women without cancer. Therefore, it is important to pay particular attention to the development of other malignancies during follow-up in patients with BC. This should be considered especially in patients with a proven genetic mutation.

Mucinous Cystic Neoplasm of Mesentery: A Case Report

Mucinous cystic neoplasms are very rare tumours. They may originate from ovaries, pancreas or other intra-abdominal sites but they rarely originate from the mesentery. They can be asymptomatic or present as an abdominal mass or abdominal pain. We present the case of a 28-year-old woman who presented with epigastric pain and cystic mass per abdomen with a diagnosis of mesenteric cyst made on further imaging studies. Subsequent excision and histopathological analysis demonstrated the cyst to be a mucinous tumour arising from the mesocolon. Mesenteric cyst must be considered as one of the differentials in abdominal cystic lesions. 

Analysis of serum HE4 levels in various histologic subtypes of epithelial ovarian cancer and other malignant tumors

BACKGROUND: The measurement of serum HE4 levels has emerged as a sensitive and specific biomarker for epithelial ovarian cancers (EOCs). However, serum levels in women diagnosed with various histologic subtypes of EOC and in women with metastatic non-ovarian primary malignancies have not been widely reported. OBJECTIVE: The goal of this study was to identify how serum HE4 levels vary in women diagnosed with different histologic subtypes of EOC and non-ovarian malignancies. METHODS: Data from six prospective pelvic mass clinical trials was combined and an evaluation of serum HE4 levels in women diagnosed with a malignancy was performed. For all patients, serum was obtained prior to surgery and final pathology, including primary tumor site, histologic subtype, grade and stage, were recorded. The mean, median, standard deviation, maximum, and minimum HE4 levels were determined for each group. RESULTS: A total of 984 patients were included in this study, with the average patient age being 60 years old. There were 230 premenopausal and 754 postmenopausal patients. Serum HE4 levels were elevated (≥70.0 pMol) in 85%of EOCs, 40%of LMP tumors, 21%of non-EOCs (germ cell tumors), 25%of cervical cancers, and 47%of non-gynecologic metastatic cancers. Analysis of histologic subtypes revealed 90%(n = 391) of serous, 85%(n = 73) of endometrioid, 45%(n = 42) of mucinous, 86%(n = 51) of mixed tumors, and 69%(n = 36) of clear cell tumors had elevated serum HE4 levels. CONCLUSIONS: Serum HE4 levels are most often elevated in women with high grade serous and endometrioid EOCs, and though serum elevations are seen more often with advanced stage disease, HE4 is also often elevated in early stage disease and lower grade tumors.

Trends in survival of epithelial ovarian/tubal cancer by histology and socioeconomic status in Denmark 1996-2017

OBJECTIVES

To examine time trends in ovarian/tubal cancer relative survival, excess mortality, and all-cause mortality for different histological types and levels of socioeconomic position.

METHODS

Women with ovarian/tubal cancer diagnosed 1996-2017 were identified in the Danish Cancer Registry (n = 11,755). Age-standardized 5-year relative survival over time was estimated by histology, socioeconomic status, and stage. Furthermore, 5-year excess mortality rate ratios (EMRR) according to calendar time for all categories of histology and socioeconomic status were calculated using a Poisson regression model. Finally, all-cause mortality by histology and socioeconomic status was estimated in multivariate Cox proportional hazards regression models.

RESULTS

Statistically significant improvements in 5-year relative survival occurred for all histological types over time except mucinous tumors (5-year EMRR, localized: 0.92 (95% CI: 0.71-1.16); advanced: 0.96 (95% CI: 0.85-1.08). Increase in relative survival over time and corresponding decrease in excess mortality was observed for all categories of socioeconomic status except for women with localized disease in the lowest income group (5-year EMRR = 0.91 (95% CI:0.76-1.10)). The impact of histology and socioeconomic status on all-cause mortality depended on time since diagnosis. Among the socioeconomic factors, especially low educational level and living alone were associated with increased all-cause mortality, particularly in the first year after diagnosis.

CONCLUSIONS

Ovarian/tubal cancer survival generally increased over time across histological types and socioeconomic factors. However, the lack of improvement for mucinous tumors needs further research. Additionally, the results for women with low income and education shows that continued focus on social equality in survival is necessary.

Translational Physiology of Anti-Müllerian Hormone: Clinical Applications in Female Fertility Preservation and Cancer Treatment

Background

Whilst the ability of AMH to induce the regression of the Müllerian ducts in the male fetus is well appreciated, AMH has additional biological actions in relation to steroid biosynthesis and ovarian follicle dynamics. An understanding of the physiology of AMH illuminates the potential therapeutic utility of AMH to protect the ovarian reserve during chemotherapy and in the treatment of female malignancies. The translation of the biological actions of AMH into clinical applications is an emerging focus of research, with promising preliminary results.

Objective and Rationale

Studies indicate AMH restrains primordial follicle development, thus administration of AMH during chemotherapy may protect the ovarian reserve by preventing the mass activation of primordial follicles. As AMH induces regression of tissues expressing the AMH receptor (AMHRII), administration of AMH may inhibit growth of malignancies expressing AMHR II. This review evaluates the biological actions of AMH in females and appraises human clinical applications.

Search Methods

A comprehensive search of the Medline and EMBASE databases seeking articles related to the physiological functions and therapeutic applications of AMH was conducted in July 2021. The search was limited to studies published in English.

Outcomes

AMH regulates primordial follicle recruitment and moderates sex steroid production through the inhibition of transcription of enzymes in the steroid biosynthetic pathway, primarily aromatase and 17α-hydroxylase/17,20-lyase. Preliminary data indicates that administration of AMH to mice during chemotherapy conveys a degree of protection to the ovarian reserve. Administration of AMH at the time of ovarian tissue grafting has the potential to restrain uncontrolled primordial follicle growth during revascularization. Numerous studies demonstrate AMH induced regression of AMHR II expressing malignancies. As this action occurs via a different mechanism to traditional chemotherapeutic agents, AMH has the capacity to inhibit proliferation of chemo-resistant ovarian cancer cells and cancer stem cells.

Wider Implications

To date, AMH has not been administered to humans. Data identified in this review suggests administration of AMH would be safe and well tolerated. Administration of AMH during chemotherapy may provide a synchronistic benefit to women with an AMHR II expressing malignancy, protecting the ovarian reserve whilst the cancer is treated by dual mechanisms.

PET/CT Variants and Pitfalls in Gynecological Cancers

The role of hybrid imaging with 2-[18F] flourodeoxyglucose (FDG) positron emission tomography and computed tomography (PET/CT) is continuously evolving and now considered standard practice in evaluation of disease stage, treatment response, recurrent disease and follow-up for numerous primary malignancies. In gynecological malignancies FDG PET/CT plays an important role, not only in the assessment of disease in the pre-and post-therapy setting, but also in radiation therapy (RT) planning by defining the metabolically active gross tumor volume (GTV. The glucose analogue radiotracer, FDG, is by far the most utilized radiotracer in PET/CT and is typically seen with high uptake in malignant cells. The radiotracer FDG has a high sensitivity but low specificity for malignancy, as benign processes with an inflammatory response for example infection, are also FDG-avid. In the evaluation of the female pelvic region an awareness of potential confounding factors in the interpretation of FDG is essential as variations of FDG uptake occur in accordance with the menstrual cycle and the menopausal state. Incidental imaging findings in the female genital can pose differential diagnostic challenges as false-positive and false-negative findings in benign and malignant processes are not uncommon. Gynecological malignancies continue to pose major public health problems with cervical cancer as the fourth most common cancer in women ranking after breast cancer, colorectal cancer and lung cancer. Familiarity with frequently encountered benign and malignant variants and pitfalls in FDG PET/CT in the female pelvic region can aid the reader in differential diagnostic considerations.

Current update on the molecular genetics and management of hereditary ovarian cancers: a primer for radiologists

More than one-fifth of ovarian cancers are hereditary, with most of them caused by BRCA genes. Malignant ovarian neoplasms are primarily epithelial tumors, a heterogeneous group of tumors with variable genetic backgrounds that translate into different biologic behaviors and morphologic features. Radiologists play an increasingly important role in the diagnosis and management of oncology patients. Familiarity with hereditary ovarian cancers will have a positive impact on patient management and radiologists' involvement in the multidisciplinary approach needed for this delicate patient population. In this paper, we review the basic histologic and genetic backgrounds of ovarian tumors with an emphasis on hereditary ovarian cancers, as well as the effects that these factors have on patient workup, primarily with regard to imaging studies.

Ovarian Cancer-Associated Mesothelial Cells: Transdifferentiation to Minions of Cancer and Orchestrate Developing Peritoneal Dissemination

Ovarian cancer has one of the poorest prognoses among carcinomas. Advanced ovarian cancer often develops ascites and peritoneal dissemination, which is one of the poor prognostic factors. From the perspective of the "seed and soil" hypothesis, the intra-abdominal environment is like the soil for the growth of ovarian cancer (OvCa) and mesothelial cells (MCs) line the top layer of this soil. In recent years, various functions of MCs have been reported, including supporting cancer in the OvCa microenvironment. We refer to OvCa-associated MCs (OCAMs) as MCs that are stimulated by OvCa and contribute to its progression. OCAMs promote OvCa cell adhesion to the peritoneum, invasion, and metastasis. Elucidation of these functions may lead to the identification of novel therapeutic targets that can delay OvCa progression, which is difficult to cure.

Conceptual innovation: 4P Medicine and 4P surgery

The aim of this article is to present the concept of "4P medicine" i.e., medicine that is Personalized, Preventive, Predictive, and Participatory. We will discuss the evolution from cure-focused traditional medicine toward personalized medicine based on genome analysis. This new approach is illustrated by several clinical examples such as prevention of cardiovascular diseases (primary and secondary), prophylactic cancer surgery, targeted therapies, targeted peri-operative care and patient participation in their care. Finally, it will discuss the impact of this development on the health system of the future and the ethical questions raised by this new approach.

Expression of cancer stem cell markers CD24, EPHA1 and CD9 and their correlation with clinical outcome in epithelial ovarian tumours

BACKGROUND

There has been variability between laboratories in the identification of cancer stem cells (CSCs) markers for epithelial ovarian cancer (EOC). We have evaluated three new surface markers for EOC to identify CSCs precisely.

METHODS

Three new putative CSCs specific surface markers CD9, CD24 and EPHA1 identified by a bioinformatics approach were evaluated in normal ovary, fallopian tube and ovarian tumours.

RESULTS

The expression of CD9 alone was observed in normal ovarian surface epithelium and fallopian tube whereas CD24 and EPHA1 were not expressed (n= 5). CD24 was expressed in all tumours (N= 101) while CD9 and EPHA1 were expressed in 89 and 71 tumours, respectively. The statistical analysis showed significant correlation of the stage of the disease (p< 0.0001), type of surgery (p< 0.0001) and residual disease (p< 0.0001) with overall survival. Although expression of CD9, CD24 and EPHA1 was observed in the majority of tumours there was no significant correlation with outcome. In patients who underwent primary surgery, increased expression of CD24 significantly correlated with poor survival. The expression of CD24 was significantly reduced (p< 0.002) upon analysis of paired sections from patients prior to surgery and at interval debulking surgery (n= 16).

CONCLUSION

These findings suggest that overexpression of these new markers may be useful in identifying and targeting ovarian CSCs and CD24 may be a putative CSCs marker in ovarian cancer.

Narrative review on serous primary peritoneal carcinoma of unknown primary site: four questions to be answered

Serous peritoneal papillary carcinoma (SPPC) represents a particular cancer of unknown primary (CUP) entity that arises in the peritoneal surface lining the abdomen and pelvis without a discriminative primary tumor site. In this review, we discuss the validity of SPPC as a distinct entity. Clinically, patients with SPPC are older, have higher parity and later menarche, are more often obese and probably have poorer survival compared to those with primary ovarian cancer. Pathologically, SPPC is more anaplastic and multifocal, unlike primary ovarian cancer which is commonly unifocal. Biologically, it presents a higher expression of proliferative signals and similar cell cycle and DNA repair protein expression. These differences hint towards SPPC and primary ovarian cancer being as a spectrum of disease. Patients with SPPC are traditionally managed similarly to stage III–IV ovarian cancer. The recommended approach integrates aggressive cytoreductive surgery, hyperthermic intraperitoneal chemotherapy, and systemic chemotherapy to remove the macroscopic tumor, eradicate the microscopic residual disease, and control the microscopic metastasis. However, the available evidence lacks proper randomized or prospective studies on SPPC and is limited to retrospective series. The diligent identification of SPPC is warranted to design specific clinical trials that eventually evaluate the impact of the new therapeutics on this distinct entity.

LncRNA MALAT-1 promotes growth and metastasis of epithelial ovarian cancer via sponging microrna-22

LncRNAs and miRNAs are emerging players in epithelial ovarian cancer (EOC). LncRNA MALAT-1 and miR-22 play vital roles in the onset and development of multiple cancers. Both of them are abnormally expressed in ovarian cancer, but the molecular basis for their involvement in EOC is unclear. In this study, we found MALAT-1 was up-regulated but miR-22 was down-regulated in EOC tissues and cell lines when compared to normal ovarian epithelial cell line IOSE80. Both of MALAT-1shRNA and miR-22 mimics inhibited ovarian cell proliferation, migration, and invasion, while simultaneously overexpressing MALAT-1 and miR-22 largely canceled out this inhibitory effect. Consistently, MALAT-1 silencing and miR-22 overexpression restrained tumor growth and metastasis to lungs in nude mice, which could be largely counteracted by co-overexpressing MALAT-1 and miR-22. Mechanistically, MALAT-1 targeted and sponged miR-22, counteracting its inhibitory effect on c-myc and c-myc-mediated epithelial-mesenchymal transition. Our findings for the first time demonstrated that MALAT-1 supports EOC progression through sponging miR-22, providing a novel insight into the role of MALAT-1 in ovarian cancer.

Multimodality Imaging Approach to Ovarian Neoplasms with Pathologic Correlation

Ovarian neoplasms can be categorized on the basis of histopathologic features into epithelial surface cell tumors, germ cell tumors, sex cord-stromal tumors, and metastases. While their imaging appearance is often nonspecific, it closely parallels the gross pathologic appearance, and radiologic-pathologic correlation is helpful to aid in a deeper understanding of the subtypes. Epithelial cell neoplasms are the most common category, and they can be benign, borderline, or malignant. Specific subtypes include serous (most common), mucinous, seromucinous, endometrioid, clear cell, Brenner, and undifferentiated. High-grade serous cystadenocarcinoma accounts for the majority of malignant ovarian tumors and the most ovarian cancer deaths. While serous neoplasms are often unilocular and bilateral, mucinous neoplasms are larger, unilateral, and multilocular. Solid components, thickened septa, and papillary projections, particularly with vascularity, indicate borderline or malignant varieties. Endometrioid and clear cell carcinomas can arise within endometriomas. Fibrous tumors (cystadenofibroma, adenofibroma, fibroma or fibrothecoma, and Brenner tumors) demonstrate low T2-weighted signal intensity of their solid components, while teratomas contain lipid. The nonspecific imaging appearance of additional malignant ovarian germ cell tumors can be narrowed with tumor marker profiles. Sex cord-stromal tumors are often solid, and secondary signs from their hormonal secretion can be a clue to their diagnosis. The authors review the anatomy of the ovary and distal fallopian tube, the proposed origins of the histologic subtypes of tumors, the clinical features and epidemiology of ovarian neoplasms, and the applications of US, CT, and MRI in imaging ovarian neoplasms. The main focus is on the radiologic and pathologic features of the multiple ovarian neoplasm subtypes. An algorithmic approach to the diagnosis of ovarian neoplasms is presented. Online supplemental material is available for this article. ^©RSNA, 2020.

Fallopian Tube Basal Stem Cells Reproducing the Epithelial Sheets In Vitro-Stem Cell of Fallopian Epithelium

The fallopian tube (FT) is an important reproductive organ in females. The luminal epithelium of the FT is composed of highly polarized secretory and ciliated cells. Recently, accumulating lines of evidence have suggested that the origin of high-grade serous ovarian carcinoma (HGSC) is fallopian tube epithelial cells (FTECs). Due to the lack of a high-fidelity model for FTECs in vitro, homeostasis, differentiation, as well as the transformation of FTECs are still enigmatic. In this study, we optimized the culture condition for the stable expansion of basal stem cells, as well as inducing differentiation of basal cells into polarized secretory and ciliated cells in the air-liquid interface (ALI) condition suitable for long-term culture. This storable culture method of FTECs provides a versatile platform for studying differentiation mechanisms, intercellular communication, and transformation to HGSC, as well as the physiological function of the FT in vitro.

Potential of platinum-resensitization by Wnt signaling modulators as treatment approach for epithelial ovarian cancer

PURPOSE

Canonical Wnt/ β-catenin pathway is one mechanism being activated in platinum-resistant epithelial ovarian cancer (EOC). Detecting potential targets for Wnt pathway modulation as a putative future therapeutic approach was the aim of this study.

METHODS

Biological effects of different Wnt modulators (SB216763, XAV939 and triptolide) on the EOC cell lines A2780 and its platinum-resistant clone A2780cis were investigated via multiple functional tests. Immunohistochemistry (IHC) was carried out to compare the expression levels of Wnt marker proteins (β-catenin, snail/ slug, E-cadherin) in patient specimens and to correlate them with lifetime data.

RESULTS

We could show that activated Wnt signaling of the platinum-resistant EOC cell line A2780cis can be reversed by Wnt manipulators through SB216763 or XAV939. All Wnt manipulators tested consecutively decreased cell proliferation and cell viability. Apoptosis of A2780 and A2780cis was enhanced by triptolide in a dose-dependent manner, whereas cell migration was inhibited by SB216763 and triptolide. IHC analyses elucidated significantly different expression patterns for Wnt markers in the serous subtype. Herein, higher plasmatic snail/ slug expression is associated with improved progression-free (PFS) and overall survival (OS).

CONCLUSION

According to the described effects on EOC biology, all three Wnt manipulators seem to have the potential to augment the impact of a platinum-based chemotherapy in EOC. This is promising as a dominance of this pathway was confirmed in serous histology.

Morphological basics of ovarian tumor histogenesis

Researches about the origin of epithelial ovarian tumors (EOT) tell about its conception. In particular, the origin of cells from the secondary mullerian system. Also, in the article we examine a new hypothesis that the EOT originates in the epithelium of the fallopian tube (FT) – their contradictoriness and new conception of “precursor escape” which tries to explain the phenomenon of injuries absence of FT by high-grade serous ovarian carcinoma. Carcinogenesis from the FT represents great opportunities for reassessment of clinical data. Also, the article represents the role of stem cells of the surface epithelium of ovaries and FT in EOT carcinogenesis.

Prevalence of endosalpingiosis and other benign gynecologic lesions

Endosalpingiosis, traditionally regarded as an incidental pathological finding, was recently reported to have an association with gynecologic malignancies. To determine the prevalence of endosalpingiosis, we evaluated all benign appearing adnexal lesions using the Sectioning and Extensively Examining-Fimbria (SEE-Fim) protocol, and queried the pathology database for the presence of endosalpingiosis, gynecologic malignancy, endometriosis, Walthard nests, and paratubal cysts. Using the SEE-Fim protocol, the prevalence of endosalpingiosis, endometriosis, Walthard nests, and paratubal cysts were 22%, 45%, 33%, and 42% respectively, substantially higher than previously reported. All lesions were observed to increase with age except endometriosis which increased until menopause then decreased dramatically. Among specimens including ovarian tissue, the prevalence of implantation of at least one lesion type was ubiquitous in patients age 51 and older (93%). The clinical significance of endosalpingiosis should be a continued area of research with larger trials assessing prevalence, factors affecting incidence, and association with malignancy. Our findings contribute to elucidating the origin of ectopic lesions and gynecologic disease risk.

Non-Surgical Cancer Risk Reduction in BRCA1 Mutation Carriers: Disabling the Remote Control

Women-specific cancers are a major health issue, particularly those associated with the BRCA1 germline mutation carrier state, which include triple-negative basal breast carcinomas and high-grade serous ovarian carcinomas (referred to as extra-uterine Müllerian carcinomas). Whereas many chronic diseases can currently be prevented (e.g., cardiovascular diseases), no recent tangible progress was made in cancer prevention of BRCA1 mutation carriers apart from surgical resections of at-risk organs. This lack of progress is largely due to (1) poor understanding of the initiating events triggered by known risk factors in the development of these cancers, (2) the fact that current preventive measures rely on evidence obtained from adjuvant breast cancer treatment that fail to protect against poor prognostic cancers, and (3) problems with using cancer incidence in high-risk women as an ethically justifiable endpoint in cancer prevention trials. Here, we propose that cancer predisposition in BRCA1 mutation carriers is driven, at least in part, by cell-nonautonomous mechanisms (i.e., driven by consequences of this carrier state on hormonal and other systemic factors controlled in organs other than those that are cancer-prone) and that biomarkers of epigenomic reprogramming, hypothesized to be a direct consequence of such cell-nonautonomous mechanisms, are attractive as intermediate surrogate endpoints to assess the efficacy of cancer risk-reducing strategies targeting these mechanisms.

Reproductive and Hormonal Factors and Risk of Ovarian Cancer by Tumor Dominance: Results from the Ovarian Cancer Cohort Consortium (OC3)

BACKGROUND

Laterality of epithelial ovarian tumors may reflect the underlying carcinogenic pathways and origins of tumor cells.

METHODS

We pooled data from 9 prospective studies participating in the Ovarian Cancer Cohort Consortium. Information on measures of tumor size or tumor dominance was extracted from surgical pathology reports or obtained through cancer registries. We defined dominant tumors as those restricted to one ovary or where the dimension of one ovary was at least twice as large as the other, and nondominant tumors as those with similar dimensions across the two ovaries or peritoneal tumors. Competing risks Cox models were used to examine whether associations with reproductive and hormonal risk factors differed by ovarian tumor dominance.

RESULTS

Of 1,058 ovarian cancer cases with tumor dominance information, 401 were left-dominant, 363 were right-dominant, and 294 were nondominant. Parity was more strongly inversely associated with risk of dominant than nondominant ovarian cancer (P heterogeneity = 0.004). Ever use of oral contraceptives (OC) was associated with lower risk of dominant tumors, but was not associated with nondominant tumors (P heterogeneity = 0.01). Higher body mass index was associated with higher risk of left-dominant tumors, but not significantly associated with risk of right-dominant or nondominant tumors (P heterogeneity = 0.08).

CONCLUSIONS

These data suggest that reproductive and hormonal risk factors appear to have a stronger impact on dominant tumors, which may have an ovarian or endometriosis origin.

IMPACT

Examining the associations of ovarian cancer risk factors by tumor dominance may help elucidate the mechanisms through which these factors influence ovarian cancer risk.

The role of anti-Müllerian hormone (AMH) in ovarian disease and infertility

PURPOSE

In this review, the current knowledge on anti-Müllerian hormone (AMH) is presented, concerning its value in disease and IVF treatment as well as in terms of its prospective clinical use.

METHODS

AMH is becoming the most appropriate biomarker for the ovarian reserve measured predominantly for assisted reproductive treatment (ART) patients in comparison to the currently used antral follicle count (AFC). However, this is not the only way AMH measurements can be used in the clinics. Because of this, we reviewed the current literature for the use of AMH in current or prospective clinical practice.

RESULTS

We found that AMH has a high predictive value in assessing the ovarian reserve, which can lead to a better efficiency of in vitro fertilization (IVF) procedures. It has a high potential to be developed as a staple diagnostic marker of ovarian disease, especially for ovarian cancers and even as a possible treatment tool for certain cancers. It could potentially be used to prevent oocyte loss due to chemo- or radiotherapy.

CONCLUSION

AMH is an important hormone especially in women reproductive organs and is currently seen as the best biomarker for a multitude of uses in reproductive medicine. Currently, the biggest issue lies in the lack of international standardization of AMH. However, it is encouraging to see that there is interest in AMH in the form of research on its action and use in reproductive medicine.

Protein tyrosine phosphatase receptor type R (PTPRR) antagonizes the Wnt signaling pathway in ovarian cancer by dephosphorylating and inactivating β-catenin

Despite a lack of mutations, accumulating evidence supports an important role for the Wnt/β-catenin pathway in ovarian tumorigenesis. However, the molecular mechanism that contributes to the aberrant activation of the Wnt signaling cascade in ovarian cancer has not been fully elucidated. Here, we found that protein tyrosine phosphatase receptor type R (PTPRR) suppressed the activation of the Wnt/β-catenin pathway in ovarian cancer. We performed an shRNA-based biochemical screen, which identified PTPRR as being responsible for tyrosine dephosphorylation of β-catenin on Tyr-142, a key site controlling the transcriptional activity of β-catenin. Of note, PTPRR was down-regulated in ovarian cancers, and ectopic PTPRR re-expression delayed ovarian cancer cell growth both in vitro and in vivo Using a proximity-based tagging system and RNA-Seq analysis, we identified a signaling nexus that includes PTPRR, α-catenin, β-catenin, E-cadherin, and AT-rich interaction domain 3C (ARID3C) in ovarian cancer. Immunohistochemistry staining of human samples further suggested that PTPRR expression is inversely correlated with disease prognosis. Collectively, our findings indicate that PTPRR functions as a tumor suppressor in ovarian cancer by dephosphorylating and inactivating β-catenin. These results suggest that PTPRR expression might have utility as a prognostic marker for predicting overall survival.

Tubal ligation and endometrial Cancer risk: a global systematic review and meta-analysis

BACKGROUND

Studies on relationship between tubal ligation and endometrial cancer have led to contradictory findings. In several studies, however, a reduced endometrial cancer risk was suggested following tubal ligation. Therefore, a systematic review and meta-analysis was conducted to examine the relationship between tubal ligation and endometrial cancer risk.

METHODS

In this systematic review and meta-analysis, PubMed/Medline, Web of Science, Scopus, Embase, and Google Scholar were searched for relevant studies published up to May 30th, 2018. We compared endometrial cancer risk in women with and without tubal ligation in retrieved studies.

RESULTS

Two hundred nine studies were initially retrieved from the data bases. After exclusion of duplicates and studies which did not meet inclusion criteria, ten cohort and case-control studies, including 6,773,066 cases, were entered into the quantitative meta-analysis. There was 0.90% agreement between two researchers who searched and retrieved the studies. The summary OR (SOR) was reported using a random effect model. Begg's test suggested that there was no publication bias, but a considerable heterogeneity was observed (I² = 95.4%, P = 0.001). We pooled the raw number of tables cells (i.e. a, b, c, and d) of eight studies. The SOR suggested that tubal ligation was significantly associated with a lower risk of endometrial cancer (SOR = 0.577, 95% CI = 0.420-0.792). Also, given the rare nature of endometrial cancer (< 5%), different effect sizes were considered as comparable measures of risk. Therefore we pooled ten studies and SOR of these studies revealed that tubal ligation was significantly associated with a lower risk of endometrial cancer (SOR = 0.696, 95% CI = 0.425-0.966). Besides that, we pooled eight studies in which adjusted effect sizes were reported and a subsequent analysis revealed that the summary estimate of adjusted odds ratio (SAOR) was significant (SAOR = 0.862, 95% CI = 0.698-1.026).

CONCLUSIONS

This study revealed a protective effect of tubal ligation on endometrial cancer risk (approximately 42% lower risk of cancer). It is recommended that studies should be designed to reveal mechanisms of this relationship.

Characteristics of in Vivo Model Systems for Ovarian Cancer Studies

An understanding of the molecular pathogenesis and heterogeneity of ovarian cancer holds promise for the development of early detection strategies and novel, efficient therapies. In this review, we discuss the advantages and limitations of animal models available for basic and preclinical studies. The fruit fly model is suitable mainly for basic research on cellular migration, invasiveness, adhesion, and the epithelial-to-mesenchymal transition. Higher-animal models allow to recapitulate the architecture and microenvironment of the tumor. We discuss a syngeneic mice model and the patient derived xenograft model (PDX), both useful for preclinical studies. Conditional knock-in and knock-out methodology allows to manipulate selected genes at a given time and in a certain tissue. Such models have built our knowledge about tumor-initiating genetic events and cell-of-origin of ovarian cancers; it has been shown that high-grade serous ovarian cancer may be initiated in both the ovarian surface and tubal epithelium. It is postulated that clawed frog models could be developed, enabling studies on tumor immunity and anticancer immune response. In laying hen, ovarian cancer develops spontaneously, which provides the opportunity to study the genetic, biochemical, and environmental risk factors, as well as tumor initiation, progression, and histological origin; this model can also be used for drug testing. The chick embryo chorioallantoic membrane is another attractive model and allows the study of drug response.

PAX8 regulon in human ovarian cancer links lineage dependency with epigenetic vulnerability to HDAC inhibitors

PAX8 is a prototype lineage-survival oncogene in epithelial ovarian cancer. However, neither its underlying pro-tumorigenic mechanisms nor potential therapeutic implications have been adequately elucidated. Here, we identified an ovarian lineage-specific PAX8 regulon using modified cancer outlier profile analysis, in which PAX8-FGF18 axis was responsible for promoting cell migration in an autocrine fashion. An image-based drug screen pinpointed that PAX8 expression was potently inhibited by small-molecules against histone deacetylases (HDACs). Mechanistically, HDAC blockade altered histone H3K27 acetylation occupancies and perturbed the super-enhancer topology associated with PAX8 gene locus, resulting in epigenetic downregulation of PAX8 transcripts and related targets. HDAC antagonists efficaciously suppressed ovarian tumor growth and spreading as single agents, and exerted synergistic effects in combination with standard chemotherapy. These findings provide mechanistic and therapeutic insights for PAX8-addicted ovarian cancer. More generally, our analytic and experimental approach represents an expandible paradigm for identifying and targeting lineage-survival oncogenes in diverse human malignancies.

Association between AXIN1 gene polymorphisms and epithelial ovarian cancer in Chinese population

Aim: The study was aimed to explore the association between AXIN1 gene polymorphism and epithelial ovarian cancer (EOC) susceptibility as well as prognosis. Methods: A total of 165 EOC cases and 327 healthy controls were recruited to participate in this study. In total three tag SNPs in AXIN1 gene were genotyped using PCR-restriction fragment length polymorphism. Results: Significantly increased EOC risk was found associated with the A/C heterozygous genotype of rs12921862, the C allele and C/T genotype in the rs1805105 and the T/T genotype of rs370681. Meanwhile, Kaplan-Meier survival curves showed that patients with rs12921862 C/C genotype improved overall survival in the EOC group. Conclusion: Our results suggest that the AXIN1 gene may be related to susceptibility and overall survival in EOC.

Prophphylactic bilateral salpingngectomy: why is it worthwhile?

Malignant tumors of the ovary are characterized by late detection which is the chief factor responsible for their poor prognosis. Almost 70% of ovarian cancers are diagnosed at clinical stage III or IV. At present, effective methods for early detection of ovarian cancer are lacking. One accepted approach to reduce the risk of ovarian cancer is bilateral salpingo-oophorectomy. However, it is increasingly widely believed that even a more limited surgery of bilateral salpingectomy may be also used prophylactically as an effective means to reduce cancer risk. The procedure is based on extensive anatomopathological research on the origins of malignant cells in ovarian cancer. There is already ample scientific evidence that in a high proportion of cases the primary site of neoplastic transformation is the distal segment of the fallopian tube, from which malignant cells migrate to the ovary. However, long-term studies demonstrating the effectiveness of prophylactic salpingectomy for ovarian cancer are required. This article summarizes the benefits and disadvantages of the procedure based on currently available literature.

Ovarian cancer stem cells: What progress have we made?

Ovarian cancer (OvCa) is the most lethal gynecological malignancy in the United States primarily due to lack of a reliable early diagnostic, high incidence of chemo-resistant recurrent disease as well as profuse tumor heterogeneity. Cancer stem cells (CSCs) continue to gain attention, as they are known to resist chemotherapy, self-renew and re-populate the bulk tumor with undifferentiated and differentiated cells. Moreover, CSCs appear to readily adapt to environmental, immunologic and pharmacologic cues. The plasticity and ability to inactivate or activate signaling pathways promoting their longevity has been, and continues to be, the challenge faced in developing successful CSC targeted therapies. Identifying and understanding unique ovarian CSC markers and the pathways they utilize could reveal new therapeutic opportunities that may offer alternative adjuvant treatment options. Herein, we will discuss the current state of ovarian CSC characterization, their contribution to disease resistance, recurrence and shed light on clinical trials that may target the CSC population.

The fallopian tube, "precursor escape" and narrowing the knowledge gap to the origins of high-grade serous carcinoma

Most ovarian carcinomas are high-grade serous carcinomas (HGSC) that contain TP53 mutations, present at advanced stage, and eventually become resistant to chemotherapy. The rapid evolution of this disease has been attributed to an origin in the distal fallopian tube, in the form of serous tubal intraepithelial carcinomas (STICs). This has led to a disease model where malignancy develops first in the tube and spreads to the peritoneum or regional lymph nodes. However, although most early or incidentally discovered HGSCs manifest in the tube with STICs, many advanced HGSCs are not accompanied by a malignancy in the fimbria. To resolve this paradox, the focus has shifted to earlier, premalignant serous proliferations (ESPs) in the tubes, which lack the cytomorphologic features of malignancy but contain TP53 mutations. These have been termed p53 signatures or serous tubal intraepithelial lesions (STILs). Although they have not been presumed to have cancer-causing potential by themselves, some ESPs have recently been shown to share identical TP53 mutations with concurrent HGSCs, indicating a shared lineage between these early mucosal changes and metastatic malignancy. This discovery supports a paradigm by which HGSCs can emerge not only from STICs but also from exfoliated precursor cells (precursor escape) that eventually undergo malignant transformation within the peritoneal cavity. This paradigm unifies both localized and widespread HGSCs to a visible pre-existing cellular alteration in the tubal epithelium, and highlights a consistent and necessary biologic event (TP53 mutation) rarely encountered in the ovary or secondary Mullerian system. This dual pathway to HGSCs underscores the subtle nature of many serous cancer origins in the tube, explains contrasting clinico-pathologic presentations, and explains why, until recently, the fallopian tube was unappreciated as the principal origin of HGSCs. Moreover, it highlights additional challenges faced in preventing or intercepting HGSCs at a curable stage.

Ovarian cancer stem cells and their role in drug resistance

Ovarian cancer is typically diagnosed at advanced stages (III or IV), with metastasis ensuing at stage III. Complete remission is infrequent and is not achieved in almost half of the women diagnosed with ovarian cancer. Consequently, management and treatment of this disease is challenging as many patients are faced with tumour recurrence disseminating to surrounding organs further complicated with acquired chemo-resistance. The cancer stem cell theory proposes the idea that a drug resistant subset of tumour cells drive tumour progression, metastasis and ultimately, recurrent disease. In the ovarian cancer field, cancer stem cells remain elusive with significant gaps in our knowledge. The characteristics and specific role of ovarian cancer stem cells in recurrence still requires further research since different studies often arrive at contradictory conclusions. Here we present a review and critical analysis of current research conducted in the field of ovarian cancer stem cells and their potential role in drug resistance including several signalling pathways within these cells that affect the viability of targeted therapies.

Back to the Future? The Fallopian Tube, Precursor Escape and a Dualistic Model of High-Grade Serous Carcinogenesis

Beginning with the discovery of the BRCA-associated ovarian cancer susceptibility genes and subsequent detailed examination of risk-reducing salpingo-oophorectomy (RRSO) specimens, a new paradigm of ovarian carcinogenesis has unfolded with attention to the distal fallopian tube. The primary focus has been an early cancer or neoplasm in the fallopian tube which is seen in virtually all incidentally discovered high-grade serous cancers in asymptomatic women. This high-frequency of tubal involvement in early serous neoplasm (usually in the form of serous tubal intraepithelial carcinoma—STIC) has galvanized attention to this organ as a primary source of this disease. However, an enduring mystery has been the relatively low frequency of STIC in the fallopian tubes of women with advanced malignancy. This paradox, a high frequency of tubal involvement early on and a low frequency of involvement later in the disease process, has spurred interest in other potential sources, such as the ovarian surface epithelium or cortical inclusions and the secondary Mullerian system. However, because essentially all high-grade serous carcinomas are linked by TP53 mutations, and because fallopian tubes frequently contain early serous proliferations (ESPs) with these mutations, attention has turned to the possibility that the nonmalignant but TP53 mutated tubal epithelium could be responsible for an eventual malignancy. Recent data have shown evidence of a lineage continuity between ESPs and concurrent serous carcinomas prompting the concept of “precursor escape”. This creates a second component of the paradigm by which cells from early precursors are shed from the tube and undergo subsequent malignant transformation, emerging suddenly as widespread intraperitoneal malignancy. This dualistic model thus provides a unique pathway by which the future outcome (wide spread high-grade serous carcinomas—HGSC) is ultimately explained by going back in time to an early serous proliferation. This paradigm also brings the peritoneal cavity into focus, raising new questions about the potential co-variables or exposures that might facilitate the occasional malignant transformation of an ESP in the peritoneal cavity or on the peritoneal surface.