The Prevent Ovarian Cancer Program (POCP): Identification of women at risk for ovarian cancer using complementary recruitment approaches.

BACKGROUND: Up to 20% of high-grade serous ovarian carcinomas (HGSOC) are hereditary; however, historical uptake of genetic testing is low. We used a unique combination of approaches to identify women in Ontario, Canada, with a first-degree relative (FDR) who died from HGSOC without prior genetic testing, and offer them multi-gene panel testing. METHODS: From May 2015-Sept 2019, genetic counseling and testing was provided to eligible participants. Two recruitment strategies were employed, including self-identification in response to an outreach campaign and direct targeting of FDRs of deceased HGSOC patients treated at our institution. The rate of pathogenic variants (PV) in established/potential ovarian cancer risk genes and the benefits/challenges of each approach were assessed. RESULTS: A total of 564 women enrolled in response to our outreach campaign (n = 473) or direct recruitment (n = 91). Mean age at consent was 52 years and 96% did not meet provincial testing criteria. Genetic results were provided to 528 individuals from 458 families. The rate of PVs in ovarian cancer risk genes was highest when FDRs were diagnosed with HGSOC <60 years (9.4% vs. 3.9% ≥ 60y, p = 0.0160). Participants in the outreach vs. direct recruitment cohort had a similar rate of PVs; however, uptake of genetic testing (97% vs. 89%; p = 0.0036) and study completion (95% vs. 87%; p = 0.0062) rates were higher in the former. Eleven participants with pathogenic variants have completed risk-reducing gynecologic surgery, with one stage I HGSOC and two breast cancers identified. CONCLUSION: Overall PV rates in this large cohort were lower than expected; however, we provide evidence that genetic testing criteria in Ontario should include individuals with a deceased FDR diagnosed with HGSOC <60 years of age.

Modified panel-based genetic counseling for ovarian cancer susceptibility: A randomized non-inferiority study.

OBJECTIVE: Genetic testing identifies cancer patients who may benefit from targeted treatment and allows for enhanced cancer screening and risk-reduction in their at-risk relatives. Traditional models of genetic counseling (GC) cannot meet the increasing demand and urgency for genetic testing. The objective of this study was to evaluate a new model of service delivery to improve the efficiency of pre-test GC for panel-based genetic testing. METHODS: A parallel, two-armed, randomized non-inferiority study compared traditional and modified pre-test GC models (1:2) prior to panel-based genetic testing. Participants were adult females, whose first-degree relative died of serous ovarian cancer. In the modified group, participants were emailed a 20-minute presentation prior to a scheduled pre-test GC telephone call. Psychosocial and knowledge questionnaires were provided at baseline (P1) and one week after pre-test GC (P2). RESULTS: 382 women completed pre-test GC (256 modified, 126 traditional). There were no differences in marital status, education level or household income. Pre-test GC time was shorter in the modified group (average 19 vs. 46 min, p < 0.001), with no difference in post-test GC time (average 16 min each, p = 0.78). The modified pre-test GC model was found to be non-inferior to traditional GC on measures of cancer-specific distress, depression, anxiety, decisional conflict, ovarian cancer knowledge and satisfaction. Perceived lifetime risk for ovarian cancer decreased to a lesser extent from baseline in women who received modified pre-test GC. CONCLUSIONS: A 20-minute presentation prior to pre-test telephone GC is non-inferior to traditional in-person GC on all variables tested, except for perceived ovarian cancer risk. This modified model improved GC efficiency without negatively affecting psychosocial outcomes, providing an alternative strategy to meet the growing demand for genetic testing.

Taking the Tube: From Normal Fallopian Tube Epithelium to Ovarian High-grade Serous Carcinoma.

Detailed pathologic studies over the past decade suggest a distal fallopian tube origin for the majority of "ovarian" high-grade serous carcinomas (HGSC). This review will summarize molecular alterations observed in tubal precursors for HGSC, namely p53 signatures and serous tubal intraepithelial carcinomas, and in nonmalignant fallopian tube epithelial cells obtained from women at increased genetic risk for HGSC. Recent experiments investigating the impact of follicular fluid exposure and retrograde menstruation on tumor development in the fallopian tube will also be discussed. These data will be reconciled with traditional ovarian cancer risk factors related to reproductive history.

The optimal time for surgery in women with serous ovarian cancer.

BACKGROUND: Advanced high-grade serous ovarian carcinoma (HGSC) is commonly treated with surgery and chemotherapy. We investigated the survival of patients treated with primary or interval surgery at different times following neoadjuvant chemotherapy. Their survival was compared with that of patients treated with primary cytoreductive surgery and adjuvant chemotherapy. METHODS: Patients with stage III or IV HGSC were included in this retrospective cohort study. Clinical data were obtained from patient records. Patients were divided into 2 groups based on treatment with neoadjuvant chemotherapy and interval cytoreductive surgery (NAC) or with primary cytoreductive surgery and adjuvant chemotherapy (PCS). Study groups were stratified by several clinical variables. RESULTS: We included 334 patients in our study: 156 in the NAC and 178 in the PCS groups. Survival of patients in the NAC group was independent of when they underwent interval cytoreductive surgery following initiation of neoadjuvant chemotherapy (p < 0.001). Optimal surgical cytoreduction had no impact on overall survival in the NAC group (p < 0.001). Optimal cytoreduction (p < 0.001) and platinum sensitivity (p < 0.001) were independent predictors of improved survival in the PCS but not in the NAC group. Patients in the NAC group had significantly worse overall survival than those in the PCS group (31.6 v. 61.3 mo, p < 0.001). CONCLUSION: Women with advanced HGSC who underwent PCS had better survival than those who underwent interval NAC, regardless of the number of cycles of neoadjuvant therapy. Optimal cytoreduction did not provide a survival advantage in the NAC group.

BACKGROUND: La chirurgie et la chimiothérapie sont habituellement le traitement recommandé pour les carcinomes ovariens séreux bien différenciés de haut grade. Nous avons étudié le taux de survie de patientes ayant subi une chirurgie initiale ou d'intervalle à divers moments après une chimiothérapie néoadjuvante et l'avons comparé avec celui de patientes ayant subi une chirurgie de réduction tumorale initiale et une chimiothérapie adjuvante. METHODS: Cette étude de cohorte rétrospective a été menée auprès de patientes présentant un carcinome de stade III ou IV. Les données cliniques ont été tirées de leur dossier médical. Les patientes ont été séparées en 2 groupes : le premier était formé des patientes ayant subi une chimiothérapie néoadjuvante et une chirurgie de réduction tumorale d'intervalle (groupe NAC), et le deuxième de celles ayant subi une chirurgie de réduction tumorale initiale et une chimiothérapie adjuvante (groupe PCS). On a stratifié les 2 groupes à l'aide de plusieurs variables cliniques. RESULTS: L'étude portait sur 334 patientes, soit 156 dans le groupe NAC et 178 dans le groupe PCS. Dans le groupe NAC, aucune corrélation n'a été observée entre le taux de survie des patientes et le temps écoulé entre la chimiothérapie néoadjuvante et la chirurgie de réduction tumorale d'intervalle (p < 0,001). La réduction tumorale optimale n'a eu aucune incidence sur le taux de survie global des patientes du groupe NAC (p < 0,001). La réduction tumorale optimale (p < 0,001) et la sensibilité au platine (p < 0,001) ont été ciblés comme étant 2 prédicateurs indépendants d'un taux de survie accru chez les patientes du groupe PCS, mais pas chez celles du groupe NAC. Le taux de survie des patientes du groupe NAC était beaucoup plus faible que celui des patientes du groupe PCS (31,6 mo contre 61,3 mo, p < 0,001). CONCLUSION: Les femmes atteintes d'un carcinome ovarien séreux bien différencié de haut grade ayant subi une chirurgie de réduction tumorale initiale et une chimiothérapie adjuvante (PCS) ont affiché un taux de survie plus élevé que les patientes ayant subi une chimiothérapie néoadjuvante et une chirurgie de réduction tumorale d'intervalle (NAC), peu importe le nombre de cycles de chimiothérapie néoadjuvante. La réduction tumorale optimale n'a pas été associée à un taux de survie plus élevé chez ces dernières.

Performance characteristics of screening strategies for Lynch syndrome in unselected women with newly diagnosed endometrial cancer who have undergone universal germline mutation testing.

BACKGROUND: Immunohistochemistry (IHC) for mismatch repair protein expression, microsatellite instability (MSI) testing, tumor morphology, and family history were compared to determine which screening strategy is superior in identifying Lynch syndrome (LS) in unselected women with newly diagnosed endometrial cancer (EC) who have undergone universal germline mutation testing. METHODS: A prospective cohort study was performed that recruited women with newly diagnosed EC. Participants completed a family history assessment with molecular characterization of EC with IHC and MSI testing and EC assessment for LS-associated morphologic features and underwent universal germline mutation testing for mutations in the mismatch repair pathway. The sensitivity, specificity, and positive and negative predictive values were compared between the screening strategies. RESULTS: A total of 118 (65%) of 182 consecutive women with EC participated. Of these, 34 women (29%) had tumors that were IHC deficient and 27 women (23%; N = 117) had tumors that were positive for MSI. Twenty women (17%) met IHC criteria and 16 women (15.2%, N = 105) met family history criteria based on Ontario Ministry of Health Criteria for the genetic assessment for LS. Seven women (5.9%) had a germline mutation: 4 had MLH1 (mutL homolog 1), 2 had MSH6 (mutS homolog 6), and 1 had MSH2 (mutS homolog 2). IHC in women aged <60 years had the best performance characteristics, with a sensitivity of 100%, a specificity of 86.1%, a positive predictive value of 58.3%, and a negative predictive value of 100%. Family history and tumor morphology both had the lowest sensitivity at 71.4%. Overall tumor morphology had the poorest performance, with a specificity of 42.1%. CONCLUSIONS: The mutation rate of 5.9% was higher than expected in this unselected cohort of women with EC. The superior screening strategy to identify women presenting with EC is universal IHC screening in women aged <60 years.

Ovarian and endometrial endometrioid carcinomas have distinct CTNNB1 and PTEN mutation profiles.

Ovarian endometrioid carcinomas and endometrial endometrioid carcinomas share many histological and molecular alterations. These similarities are likely due to a common endometrial epithelial precursor cell of origin, with most ovarian endometrioid carcinomas arising from endometriosis. To directly compare the mutation profiles of two morphologically similar tumor types, endometrial endometrioid carcinomas (n=307) and ovarian endometrioid carcinomas (n=33), we performed select exon capture sequencing on a panel of genes: ARID1A, PTEN, PIK3CA, KRAS, CTNNB1, PPP2R1A, TP53. We found that PTEN mutations are more frequent in low-grade endometrial endometrioid carcinomas (67%) compared with low-grade ovarian endometrioid carcinomas (17%) (P<0.0001). By contrast, CTNNB1 mutations are significantly different in low-grade ovarian endometrioid carcinomas (53%) compared with low-grade endometrial endometrioid carcinomas (28%) (P<0.0057). This difference in CTNNB1 mutation frequency may be reflective of the distinct microenvironments; the epithelial cells lining an endometriotic cyst within the ovary are exposed to a highly oxidative environment that promotes tumorigenesis. Understanding the distinct mutation patterns found in the PI3K and Wnt pathways of ovarian and endometrial endometrioid carcinomas may provide future opportunities for stratifying patients for targeted therapeutics.

Intratumoral heterogeneity in a minority of ovarian low-grade serous carcinomas.

BACKGROUND: Ovarian low-grade serous carcinoma (LGSC) has fewer mutations than ovarian high-grade serous carcinoma (HGSC) and a less aggressive clinical course. However, an overwhelming majority of LGSC patients do not respond to conventional chemotherapy resulting in a poor long-term prognosis comparable to women diagnosed with HGSC. KRAS and BRAF mutations are common in LGSC, leading to clinical trials targeting the MAPK pathway. We assessed the stability of targetable somatic mutations over space and/or time in LGSC, with a view to inform stratified treatment strategies and clinical trial design. METHODS: Eleven LGSC cases with primary and recurrent paired samples were identified (stage IIB-IV). Tumor DNA was isolated from 1-4 formalin-fixed paraffin-embedded tumor blocks from both the primary and recurrence (n = 37 tumor and n = 7 normal samples). Mutational analysis was performed using the Ion Torrent AmpliSeqTM Cancer Panel, with targeted validation using Fluidigm-MiSeq, Sanger sequencing and/or Raindance Raindrop digital PCR. RESULTS: KRAS (3/11), BRAF (2/11) and/or NRAS (1/11) mutations were identified in five unique cases. A novel, non-synonymous mutation in SMAD4 was observed in one case. No somatic mutations were detected in the remaining six cases. In two cases with a single matched primary and recurrent sample, two KRAS hotspot mutations (G12V, G12R) were both stable over time. In three cases with multiple samplings from both the primary and recurrent surgery some mutations (NRAS Q61R, BRAF V600E, SMAD4 R361G) were stable across all samples, while others (KRAS G12V, BRAF G469V) were unstable. CONCLUSIONS: Overall, the majority of cases with detectable somatic mutations showed mutational stability over space and time while one of five cases showed both temporal and spatial mutational instability in presumed drivers of disease. Investigation of additional cases is required to confirm whether mutational heterogeneity in a minority of LGSC is a general phenomenon that should be factored into the design of clinical trials and stratified treatment for this patient population.

Opportunistic salpingectomy: uptake, risks, and complications of a regional initiative for ovarian cancer prevention.

OBJECTIVE: The purpose of this study was to assess the uptake and perioperative safety of bilateral salpingectomy (BS) as an ovarian cancer risk-reduction strategy in low-risk women after a regional initiative that was aimed at general gynecologists in the province of British Columbia, Canada. STUDY DESIGN: This population-based retrospective cohort study evaluated 43,931 women in British Columbia from 2008-2011 who underwent hysterectomy that was performed with and without BS or bilateral salpingo-oophorectomy or who underwent surgical sterilization by means of BS or tubal ligation. Parameters that were examined include patient age, operating time, surgical approach, indication, length of hospital stay, and perioperative complications. RESULTS: There was an increase in the uptake of hysterectomy with BS (5-35%; P < .001) and BS for sterilization (0.5-33%; P < .001) over the study period, particularly in women <50 years old. Minimal additional surgical time is required for hysterectomy with BS (16 minutes; P < .001) and BS for sterilization (10 minutes; P < .001) compared with hysterectomy alone or tubal ligation, respectively. No significant differences were observed in the risks of hospital readmission or blood transfusions in women who underwent hysterectomy with BS (adjusted odds ratio [aOR], 0.91; 95% confidence interval [CI], 0.75-1.10; and aOR, 0.86; 95% CI, 0.67-1.10, respectively) or BS for sterilization (aOR, 0.8; 95% CI, 0.56-1.21; and aOR, 0.75; 95% CI, 0.32-1.73, respectively). From 2008-2011 the proportion of hysterectomies with BS performed by open laparotomy decreased from 77-44% with uptake in laparoscopic, vaginal, and combined procedures (P < .001). CONCLUSION: After our 2010 educational initiative, there has been a shift in surgical paradigm in our province. This cancer prevention approach does not increase the risk of operative/perioperative complications and appears both feasible and safe.

The fallopian tube as the origin of high grade serous ovarian cancer: review of a paradigm shift.

Research published over the past 10 years has suggested that most "ovarian cancer," and specifically the high-grade serous carcinoma (HGSC) subtype of ovarian cancer, actually originates in the fallopian tube. In this review, we examine the evidence supporting the tubal origin hypothesis for HGSC, and discuss the clinical implications of our improved understanding of the pathogenesis of ovarian cancer. We searched Medline R and Medline in-process and non-indexed citations from inception to December 15, 2012, to identify all English or French language articles discussing the origins of HGSC. Articles and findings were summarized descriptively. A step-wise transformation from normal epithelium to a lesion with the ability to invade and metastasize has been demonstrated within the fallopian tube. Intraepithelial or early invasive carcinoma of the fallopian tube is frequently identified in BRCA mutation carriers who undergo prophylactic risk-reducing salpingo-oophorectomy. In both BRCA mutation carriers and women from the general population, pre-invasive changes within the fimbriated end of the fallopian tube appear in association with early HGSC. Molecular and genetic studies, as well as in vitro and animal models, have also supported a tubal origin for HGSC. Whether the removal of fallopian tubes (salpingectomy) at the time of pelvic surgery for other reasons will lead to reductions in mortality from ovarian cancer is currently unknown, but it is an important area for future clinical research.

Les recherches publiées au cours des 10 dernières années ont laissé entendre que la plupart des « cancers de l'ovaire ¼ (et plus particulièrement le sous-type « carcinome séreux de haut grade histologique ¼ [CSHG] du cancer de l'ovaire) trouvent en fait leur origine dans la trompe de Fallope. Dans le cadre de cette analyse, nous examinons les données soutenant l'hypothèse de l'origine tubaire du CSHG et nous discutons des implications cliniques de notre compréhension améliorée de la pathogenèse du cancer de l'ovaire. Nous avons mené des recherches dans Medline R et dans les citations en traitement et non répertoriées de Medline en vue d'en tirer tous les articles publiés en anglais ou en français discutant des origines du CSHG, et ce, du début de notre étude jusqu'au 15 décembre 2012. Les articles et les constatations ont été résumés de façon descriptive. Une transformation progressive de l'épithélium normal en lésion ayant la capacité d'envahir les tissus voisins et de produire des métastases a été démontrée au sein de la trompe de Fallope. La présence d'un carcinome intraépithélial ou invasif précoce de la trompe de Fallope est fréquemment identifiée chez les porteuses de la mutation BRCA qui subissent une salpingo-ovariectomie prophylactique d'atténuation du risque. Tant chez les porteuses de la mutation BRCA que chez les femmes de la population générale, des modifications préinvasives affectant la frange ovarienne se manifestent en association avec l'apparition d'un CSHG précoce. Des études moléculaires et génétiques (ainsi que des études in vitro et menées sur des modèles animaux) ont également soutenu l'hypothèse de l'origine tubaire du CSHG. Bien que nous ne disposions toujours pas d'une réponse à la question de savoir si le retrait des trompes de Fallope (salpingectomie) au moment d'une chirurgie pelvienne effectuée pour d'autres raisons mène à une baisse du taux de mortalité attribuable au cancer de l'ovaire, elle demeure néanmoins un domaine d'intérêt important pour les futures recherches cliniques.

Risk-reducing salpingectomy in Canada: a survey of obstetrician-gynaecologists.

OBJECTIVE: Performing risk-reducing salpingectomy (RRS) at the time of hysterectomy or as a method of tubal ligation has been suggested as a way to reduce the incidence of high grade serous carcinoma (HGSC) of the ovary, since this type of cancer is hypothesized to originate in the fallopian tube. We conducted a survey of Canadian obstetrician-gynaecologists to better understand the uptake and knowledge of implementing this procedure, and to identify barriers to doing so. METHODS: An anonymous, web-based survey using both quantitative and qualitative methods was sent to obstetrician-gynaecologist members of the Society of Obstetricians and Gynaecologists of Canada and the Society of Gynecologic Oncology of Canada. The survey contained questions about demographics, knowledge and beliefs about RRS, and possible barriers to its implementation in women at average risk for ovarian cancer. RESULTS: One hundred ninety-two physicians responded to the survey, a response rate of 25%. Respondents varied in their duration in practice, came from all provinces, and spent a large proportion of their time practising gynaecology. Ninety percent of respondents had heard of RRS; however, 37% were unaware of the evidence supporting the hypothesis that HGSC originates in the fallopian tube, and 38% were unsure whether there would be any population benefit from performing RRS at the time of other gynaecologic surgery. Multiple barriers to implementation were identified. CONCLUSION: Most Canadian obstetrician-gynaecologists responding to our survey were aware of RRS as a possible method to prevent ovarian cancer in women at average risk; however, barriers still exist to widespread implementation. Further research is needed to quantify the population benefit of this procedure.

Objectif : La tenue d'une salpingectomie de réduction du risque (SRR) au moment d'une hystérectomie ou comme moyen de procéder à une ligature des trompes a été suggérée à titre de façon de réduire l'incidence du carcinome séreux de grade élevé (CSGE) de l'ovaire, puisque l'on soupçonne que ce type de cancer trouve son origine dans la trompe de Fallope. Nous avons mené un sondage auprès d'obstétriciens-gynécologues canadiens afin de déterminer leurs connaissances sur le sujet, de mieux comprendre les facteurs qui influencent leurs opinions quant à cette intervention et de cerner les obstacles à la mise en œuvre de cette dernière. Méthodes : Nous avons fait parvenir un sondage Web anonyme utilisant des méthodes tant quantitatives que qualitatives aux obstétriciens-gynécologues étant membres de la Société des obstétriciens et gynécologues du Canada et de la Société de gynéco-oncologie du Canada. Ce sondage contenait des questions au sujet des caractéristiques démographiques des répondants, de leurs connaissances et de leurs opinions quant à la SRR, ainsi qu'au sujet des obstacles possibles à la mise en œuvre de cette dernière chez des femmes exposées à un risque moyen de cancer de l'ovaire. Résultats : Le nombre de répondants au sondage a été de 192, soit un taux de réponse de 25 %. La durée de pratique variait d'un répondant à l'autre : ils provenaient de toutes les provinces et passaient une grande partie de leur temps à pratiquer la gynécologie. Quatre-vingt-dix pour cent des répondants avaient entendu parler de la SRR; toutefois, 37 % n'étaient pas au courant des données soutenant l'hypothèse selon laquelle le CSGE trouve son origine dans la trompe de Fallope et 38 % demeuraient indécis quant à la question de savoir si la tenue d'une SRR au moment de l'exécution d'une autre chirurgie gynécologique pouvait entraîner quelque avantage que ce soit au niveau populationnel. De multiples obstacles à la mise en œuvre ont été identifiés. Conclusion : La plupart des obstétriciens-gynécologues canadiens ayant répondu à notre sondage connaissaient le potentiel de la SRR à titre de méthode de prévenir le cancer de l'ovaire chez les femmes exposées à des risques moyens; toutefois, il existe toujours des obstacles à la mise en œuvre à grande échelle de cette intervention. La tenue d'autres recherches s'avère requise pour en quantifier les avantages au niveau populationnel.

The role of the fallopian tube in ovarian cancer.

High-grade serous carcinoma (HGSC) is the most common and lethal subtype of ovarian cancer. Research over the past decade has strongly suggested that "ovarian" HGSC arises in the epithelium of the distal fallopian tube, with serous tubal intraepithelial carcinomas (STICs) being detected in 5-10% of BRCA1/2 mutation carriers undergoing risk-reducing surgery and up to 60% of unselected women with pelvic HGSC. The natural history, clinical significance, and prevalence of STICs in the general population (ie, women without cancer and not at an increased genetic risk) are incompletely understood, but anecdotal evidence suggests that these lesions have the ability to shed cells with metastatic potential into the peritoneal cavity very early on. Removal of the fallopian tube (salpingectomy) in both the average and high-risk populations could therefore prevent HGSC, by eliminating the site of initiation and interrupting spread of potentially cancerous cells to the ovarian/peritoneal surfaces. Salpingectomy may also reduce the incidence of the 2 next most common subtypes, endometrioid and clear cell carcinoma, by blocking the passageway linking the lower genital tract to the peritoneal cavity that enables ascension of endometrium and factors that induce local inflammation. The implementation of salpingectomy therefore promises to significantly impact ovarian cancer incidence and outcomes.

Gene expression profiles of luteal phase fallopian tube epithelium from BRCA mutation carriers resemble high-grade serous carcinoma.

PURPOSE: To identify molecular alterations potentially involved in predisposition to adnexal serous carcinoma (SerCa) in the nonmalignant fallopian tube epithelium (FTE) of BRCA1/2 mutation carriers, given recent evidence implicating the distal FTE as a common source for SerCa. EXPERIMENTAL DESIGN: We obtained and compared gene expression profiles of laser capture microdissected nonmalignant distal FTE from 12 known BRCA1/2 mutation carriers (FTEb) and 12 control women (FTEn) during the luteal and follicular phase, as well as 13 high-grade tubal and ovarian SerCa. RESULTS: Gene expression profiles of tubal and ovarian SerCa specimens were indistinguishable by unsupervised cluster analysis and significance analysis of microarrays. FTEb samples as a group, and four individual FTEb samples from the luteal phase in particular, clustered closely with SerCa rather than normal control FTE. Differentially expressed genes from these four samples relative to other FTEb samples, as well as differentially expressed genes in all FTEb luteal samples relative to follicular samples, were mapped to the I2D protein-protein interaction database, revealing a complex network affecting signaling pathways previously implicated in tumorigenesis. Two candidates, disabled homolog 2 mitogen-responsive phosphoprotein (DAB2) and Ski-like (SKIL), were further validated by real-time reverse transcription-PCR and tissue arrays. FTEb luteal and SerCa samples expressed higher levels of oncogenic SKIL and decreased levels of tumor suppressor DAB2, relative to FTEb follicular samples. CONCLUSIONS: These findings support a common molecular pathway for adnexal SerCa and implicate factors associated with the luteal phase in predisposition to ovarian cancer in BRCA mutation carriers.

Altered expression of inflammation-associated genes in oviductal cells following follicular fluid exposure: implications for ovarian carcinogenesis.

Evidence indicates that high-grade serous ovarian carcinoma (HGSOC) may originate from lesions within the distal fallopian tube epithelium (FTE). Our previous studies indicate that fallopian tube epithelial cells from carriers of germline mutations in breast cancer susceptibility genes exhibit a pro-inflammatory gene expression signature during the luteal phase, suggesting that delayed resolution of postovulatory inflammatory signaling may contribute to predisposition to this ovarian cancer histotype. To determine whether exposure of tubal epithelial cells to periovulatory follicular fluid alters expression of inflammation-associated genes, we used an ex vivo culture system of bovine oviductal epithelial cells. Oviductal cells grown on collagen IV-coated transwell membranes assumed a cobblestone appearance and immunocytochemistry for FoxJ1 and Pax8 indicated that both ciliated and secretory epithelial cells were maintained in the cultures. Oviductal cells were exposed to human follicular fluid or culture medium for 24 h following which total cellular RNA was extracted at various time points. Expression of genes associated with inflammation was determined by quantitative real-time RT-PCR. Exposure to follicular fluid transiently increased the transcript levels of interleukin 8 (IL8) and cyclooxygenase 2 (PTGS2), and decreased the expression of mitochondrial superoxide dismutase (SOD2), glutathione peroxidase 3 (GPX3), disabled homolog 2 (DAB2), and glucocorticoid receptor (NR3C1). Tumor necrosis factor (TNF) and IL6 levels were also decreased while those of nicotinomide phosphoribosyltransferase (NAMPT) were unaffected. This study demonstrates that periovulatory follicular fluid can act directly upon oviductal epithelial cells to alter gene expression that might contribute to early carcinogenic events. Furthermore, these findings illustrate the potential use of bovine oviductal cells to study signaling events implicated in ovarian carcinogenesis.

Prolonged postovulatory proinflammatory signaling in the fallopian tube epithelium may be mediated through a BRCA1/DAB2 axis.

PURPOSE: To assess inflammation-related gene expression in nonmalignant fallopian tube epithelium (FTE) from BRCA1/2 mutation carriers and control patients obtained during the luteal and follicular phase, and to determine the impact of BRCA1 and disabled homolog 2 (DAB2) on NF-κB-mediated proinflammatory signaling. EXPERIMENTAL DESIGN: A list of inflammation-related and NF-κB-responsive genes was compiled through gene set enrichment and PubMed database search, corresponding probes identified, and unpaired t tests conducted to identify differentially expressed genes in previously profiled FTE samples. ES2 and A549 cells were cotransfected with DAB2- or BRCA1-targeting siRNA and an NF-κB-responsive luciferase reporter, treated with TNF-α and luciferase activity determined. To determine whether DAB2 or BRCA1 alters mRNA expression of NF-κB target genes, cells were transfected with siRNA, treated with TNF-α, and harvested for total RNA extraction and quantitative real-time PCR. RESULTS: A subset of BRCA1-mutated luteal phase samples previously found to group with adnexal high-grade serous carcinomas (HGSCs) differentially expressed 124 inflammation-associated probesets relative to remaining FTE samples. These samples also differentially expressed 264 probes relative to other luteal phase samples exposed to the same postovulatory environment. Both BRCA1- and DAB2-targeting siRNA increased TNF-α-induced NF-κB activity and mRNA expression of NF-κB-dependent target gene SOD2 relative to nontargeting siRNA, suggesting that both proteins repress proinflammatory signaling. CONCLUSIONS: These data provide evidence of elevated proinflammatory signaling in a subset of BRCA1-mutated luteal phase FTE, consistent with an altered response to ovulation-associated cytokines. Furthermore, both BRCA1 and DAB2 affect NF-κB activity, indicating a novel link between BRCA mutation status, ovulation, and predisposition to HGSC.

Decreased progesterone receptor isoform expression in luteal phase fallopian tube epithelium and high-grade serous carcinoma.

We previously reported that BRCA1/2-mutated fallopian tube epithelium (FTE) collected during the luteal phase exhibits gene expression profiles more closely resembling that of high-grade serous carcinoma (HGSC) specimens than FTE collected during the follicular phase or from control patients. Since the luteal phase is characterised by high levels of progesterone, we determined whether the expression of progesterone receptor (PR) and PR-responsive genes was altered in FTE obtained from BRCA mutation carriers during the luteal phase of the menstrual cycle. RT-qPCR confirmed a decreased expression of PR mRNA in FTE during the luteal phase relative to follicular phase, in both BRCA1/2 mutation carriers and control patients. Immunohistochemistry using isoform-specific antibodies confirmed a low level of both PR-A and PR-B in HGSC and a lower level of staining in FTE samples obtained during the luteal phase compared with the follicular phase. No significant difference in PR-A or PR-B staining was found based on patient BRCA mutation status. Analysis of our previously reported gene expression profiles based upon known PR-A- and PR-B-specific target genes did not partition samples by BRCA mutation status, indicating that overall FTE PR response is not altered in BRCA mutation carriers. HGSC samples grouped separately from other samples, consistent with the observed loss of PR expression. These findings indicate no overall difference in PR signalling in FTE as a function of BRCA mutation status. Thus, the molecular similarity of BRCA1/2-mutated luteal phase FTE and HGSC likely results from an altered response to luteal phase factors other than progesterone.