Context-dependent environmental associations with endometrial cancer histotype and genotype.

OBJECTIVE: MLH1 loss due to MLH1 methylation, detected during Lynch syndrome screening, is one of the most common molecular changes in endometrial cancer. It is well established that environmental influences such as nutritional state can impact gene methylation, both in the germline and in a tumor. In colorectal cancer and other cancer types, aging is associated with changes in gene methylation. The objective of this study was to determine if there was an association between aging or body mass index on MLH1 methylation in sporadic endometrial cancer. METHODS: A retrospective review of patients with endometrial cancer was performed. Tumors were screened for Lynch syndrome via immunohistochemistry, with MLH1 methylation analysis performed when there was loss of MLH1 expression. Clinical information was abstracted from the medical record. RESULTS: There were 114 patients with mismatch repair deficient tumors associated with MLH1 methylation, and 349 with mismatch repair proficient tumors. Patients with mismatch repair deficient tumors were older than those whose tumors were proficient. Mismatch repair deficient tumors had a higher incidence of lymphatic/vascular space invasion. When stratified by endometrioid grade, associations with body mass index and age became apparent. Patients with endometrioid grades 1 and 2 tumors and somatic mismatch repair deficiency were significantly older, but body mass index was comparable with that of the mismatch repair intact group. For endometrioid grade 3, patient age did not significantly vary between the somatic mismatch repair deficient group and the mismatch repair intact group. In contrast, body mass index was significantly higher in the patients with grade 3 tumors with somatic mismatch repair deficiency. CONCLUSION: The relationship of MLH1 methylated endometrial cancer with age and body mass index is complex and somewhat dependent on tumor grade. As body mass index is modifiable, it is possible that weight loss induces a 'molecular switch' to alter the histologic characteristics of an endometrial cancer.

Adjuvant treatment in early-stage endometrial cancer: context-dependent impact of somatic CTNNB1 mutation on recurrence-free survival.

OBJECTIVE: The primary objective of this study was to determine whether women whose tumors harbor a somatic CTNNB1 mutation have longer recurrence-free survival if they receive traditional adjuvant therapy strategies compared with those who do not. METHODS: A retrospective, stage I endometrial cancer cohort from MD Anderson Cancer Center was assessed. Clinical and pathological characteristics and type of adjuvant therapy (cuff brachytherapy, pelvic radiation, chemotherapy) were obtained by review of medical records. CTNNB1 exon 3 sequencing was performed. Summary statistics were calculated, and recurrence-free survival was measured using the Kaplan-Meier product-limit estimator. RESULTS: The analysis included 253 patients, 245 with information regarding adjuvant therapy. Most patients had tumors of endometrioid histology (210/253, 83%) with superficial myometrial invasion (197/250, 79%) and no lymphatic/vascular space invasion (168/247, 68%). Tumor CTNNB1 mutations were present in 45 (18%) patients. Patients receiving adjuvant therapy were more likely to have higher-grade tumors, non-endometrioid histology, deep myometrial invasion, and lymphatic/vascular invasion. For patients with low-risk features not receiving adjuvant therapy, the presence of CTNNB1 mutation did not significantly impact recurrence-free survival (11.3 years wild-type vs 8.1 years mutant, p=0.65). The cohort was then limited to intermediate-risk tumors, defined as endometrioid histology of any grade with deep myometrial invasion and/or lymphatic/vascular space invasion. When recurrence-free survival was stratified by CTNNB1 mutation status and adjuvant therapy, patients with CTNNB1 mutations and no adjuvant therapy had the shortest recurrence-free survival at 1.6 years, followed by patients with CTNNB1 mutations who received adjuvant therapy (4.0 years), and wild-type CTNNB1 with and without adjuvant therapy (8.5 and 7.2 years, respectively) (comparison for all four groups, p=0.01). CONCLUSION: In patients with intermediate-risk endometrioid endometrial cancers, the use of adjuvant therapy was associated with an improvement in recurrence-free survival for patients with tumor mutations in CTNNB1.

MIG-6 Is Critical for Progesterone Responsiveness in Human Complex Atypical Hyperplasia and Early-Stage Endometrial Cancer.

Women with complex atypical hyperplasia (CAH) or early-stage endometrioid endometrial cancer (EEC) are candidates for fertility preservation. The most common approach is progesterone (P4) therapy and deferral of hysterectomy until after completion of childbearing. However, P4 therapy response rates vary, and molecular mechanisms behind P4 resistance are poorly understood. One potential molecular cause of P4 resistance is a loss or attenuation of PGR expression. Mitogen-inducible gene 6 (MIG-6) is critical for P4 responsiveness. MIG-6 protein expression in the endometrial epithelial and stromal cells from women with CAH and EEC was significantly lower compared to women without CAH or EEC. The P4-responsive women (10/15) exhibited an increase of MIG-6 expression in epithelial and stromal cells compared to P4-resistant women (5/15). In addition, immunohistochemical analysis for PGR results showed that stromal PGR levels are significantly higher in P4-responsive women compared to P4-resistant women, whereas epithelial PGR expression was not different. A reverse correlation of MIG-6 and pAKT levels was observed in early-stage EEC patients. Studies strongly suggest that loss of MIG-6 and PGR and activation of pAKT lead to P4 resistance in CAH and EEC. These results will help to elucidate the molecular mechanism leading to P4 resistance in CAH and EEC.

Endometrial biomarkers in premenopausal women with obesity: an at-risk cohort.

BACKGROUND: Obesity is a well-known risk factor for endometrial cancer, but the mechanisms of obesity-related carcinogenesis are not well defined, particularly for premenopausal women. With the continuing obesity epidemic, increases in the incidence of endometrial cancer and a younger age of diagnosis are often attributed to a hyperestrogenic state created by hormone production in adipose tissue, but significant knowledge gaps remain. The balance of estrogen-responsive signals has not been defined in the endometrium of premenopausal women with obesity, where obesity may not create hyperestrogenism in the context of ovaries being the primary source of estrogen production. Obesity is associated with a state of low-grade, chronic inflammation that can promote tumorigenesis, and it is also known that hormonal changes alter the immune microenvironment of the endometrium. However, limited research has been conducted on endometrial immune-response changes in women who have an increased risk for cancer due to obesity. OBJECTIVE: Endometrial estrogen-regulated biomarkers, previously shown to be dysregulated in endometrial cancer, were evaluated in a cohort of premenopausal women to determine if obesity is associated with differences in the biomarker expression levels, which might reflect an altered risk of developing cancer. The expression of a multiplexed panel of immune-related genes was also evaluated for expression differences related to obesity. STUDY DESIGN: Premenopausal women with a body mass index of ≥30 kg/m2 (n=97) or a body mass index of ≤25 kg/m2 (n=33) were prospectively enrolled in this cross-sectional study, which included the assessment of serum metabolic markers and a timed endometrial biopsy for pathologic evaluation, hormone-regulated biomarker analysis, and immune response gene expression analysis. Medical and gynecologic histories were obtained. Endometrial gene expression markers were also compared across the body mass index groups in a previous cohort of premenopausal women with an inherited cancer risk (Lynch syndrome). RESULTS: In addition to known systemic metabolic differences, histologically normal endometria from women with obesity showed a decrease in gene expression of progesterone receptor (P=.0027) and the estrogen-induced genes retinaldehyde dehydrogenase 2 (P=.008), insulin-like growth factor 1 (P=.016), and survivin (P=.042) when compared with women without obesity. The endometrial biomarkers insulin-like growth factor 1, survivin, and progesterone receptor remained statistically significant in multivariate linear regression models. In contrast, women with obesity and Lynch syndrome had an increased expression of insulin-like growth factor 1 (P=.017). There were no differences in endometrial proliferation, and limited endometrial immune differences were observed. CONCLUSION: When comparing premenopausal women with and without obesity in the absence of endometrial pathology or an inherited cancer risk, the expression of the endometrial biomarkers does not reflect a local hyperestrogenic environment, but it instead reflects a decreased cancer risk profile that may be indicative of a compensated state. In describing premenopausal endometrial cancer risk, it may be insufficient to attribute a high-risk state to obesity alone; further studies are warranted to evaluate individualized biomarker profiles for differences in the hormone-responsive signals or immune response. In patients with Lynch syndrome, the endometrial biomarker profile suggests that obesity further increases the risk of developing cancer.

Prospective phase II trial of levonorgestrel intrauterine device: nonsurgical approach for complex atypical hyperplasia and early-stage endometrial cancer.

BACKGROUND: The incidence of complex atypical hyperplasia and early-stage endometrioid endometrial cancer is increasing, in part owing to the epidemic of obesity, which is a risk factor tightly linked to the development of endometrial hyperplasia and cancer. The standard upfront treatment for complex atypical hyperplasia and early-stage endometrial cancer is hysterectomy. However, nonsurgical treatment of early-stage endometrial neoplasia may be necessary owing to medical comorbidities precluding surgery or desired future fertility. OBJECTIVE: This study aimed to evaluate the efficacy of the levonorgestrel intrauterine device to treat complex atypical hyperplasia and grade 1 endometrioid endometrial carcinoma. STUDY DESIGN: A single-institution, single-arm, phase II study of the levonorgestrel intrauterine device (52 mg levonorgestrel, Mirena) was conducted in patients with complex atypical hyperplasia or grade 1 endometrioid endometrial cancer. The primary endpoint was pathologic response rate at 12 months, including complete or partial response. Quality of life and toxicity were assessed. Molecular analyses for proliferation markers, hormone-regulated genes, and wingless-related integration site pathway activation were performed at baseline and 3 months. RESULTS: A total of 57 patients were treated (21 endometrial cancer, 36 complex atypical hyperplasia). The median age was 48.0 years, and the median body mass index was 45.5 kg/m2. Of the 47 evaluable patients, 12-month response rate was 83% (90% credible interval, 72.7-90.3)-37 were complete responders (8 endometrial cancer; 29 complex atypical hyperplasia), 2 were partial responders (2 endometrial cancer), 3 had stable disease (2 endometrial cancer; 1 complex atypical hyperplasia), and 5 had progressive disease (3 endometrial cancer; 2 complex atypical hyperplasia). After stratification for histology, the response rate was 90.6% for complex atypical hyperplasia and 66.7% for grade 1 endometrioid endometrial cancer. Notably, 4 patients (9.5%) experienced relapse after the initial response. Adverse events were mild, primarily irregular bleeding and cramping. Quality of life was not negatively affected. At 3 months, exogenous progesterone effect was present in 96.9% of responders (31 of 32) vs 25% of nonresponders (2 of 8) (P=.001). Nonresponders had higher baseline proliferation (Ki67) and lower dickkopf homolog 3 gene expression than responders (P=.023 and P=.030). Nonresponders had significantly different changes in secreted frizzled-related protein 1, frizzled class receptor 8, and retinaldehyde dehydrogenase 2 compared with responders. CONCLUSION: The levonorgestrel intrauterine device has a substantial activity in complex atypical hyperplasia and grade 1 endometrioid endometrial cancer, with a modest proportion demonstrating upfront progesterone resistance. Potential biomarkers were identified that may correlate with resistance to therapy; further exploration is warranted.

Pathologic distribution at the time of interval tumor reductive surgery informs personalized surgery for high-grade ovarian cancer.

INTRODUCTION: The surgical approach for interval debulking surgery after neoadjuvant chemotherapy has been extrapolated from primary tumor reductive surgery for high-grade ovarian cancer. The study objective was to compare pathologic distribution of malignancy at interval debulking surgery versus primary tumor reductive surgery. METHODS: Patients with a diagnosis of high-grade serous or mixed, non-mucinous, epithelial ovarian, fallopian tube or primary peritoneal cancer who underwent neoadjuvant chemotherapy or primary tumor reductive surgery and had at least 6 months of follow-up were identified through tumor registry at a single institution from January 1995 to April 2016. Pathologic involvement of organs was categorized as macroscopic, microscopic, or no tumor. Statistical analyses included Mann-Whitney and Fisher's exact tests. RESULTS: Of 918 patients identified, 366 (39.9%) patients underwent interval debulking surgery and 552 (60.1%) patients underwent primary tumor reductive surgery. Median age was 62.3 years (range 25.3-92.5). The majority of patients in the interval debulking surgery group were unstaged (261, 71.5%). In the patients who had a primary tumor reductive surgery, 406 (74.6%) had stage III disease. In both groups, the majority of patients had serous histology: 325 (90%) and 435 (78.8%) in the interval debulking and primary tumor reductive surgery groups, respectively. There was a statistically significant difference between disease distribution on the uterus between the groups; 31.4% of the patients undergoing interval debulking surgery had no evidence of uterine disease compared with 22.1% of primary tumor reductive surgery specimens (p<0.001). In the adnexa, there was macroscopic disease present in 253 (69.2%) and 482 (87.4%) of cases in the interval vs primary surgery groups, respectively (p<0.001). Within the omentum, no tumor was present in the omentum in 52 (14.2%) in the interval surgery group versus 91 (16.5%) in the primary surgery group (p<0.001). In the interval surgery group, there was no tumor involving the small and large bowel in 49 (13.4%) and 28 (7.7%) pathologic specimens, respectively. This was statistically significantly different from the small and large bowel in the primary surgery group, of which there was no tumor in 20 (3.6%, p<0.001) and 16 (2.9%, p<0.001) of cases, respectively. CONCLUSION: In patients undergoing interval debulking surgery, there was less macroscopic involvement of tumor in the uterus, adnexa and bowel compared with patients undergoing primary cytoreductive surgery.

MLH1-rheMac hereditary nonpolyposis colorectal cancer syndrome in rhesus macaques.

Over the past two decades, 33 cases of colonic adenocarcinomas have been diagnosed in rhesus macaques (Macaca mulatta) at the nonhuman primate colony of the Keeling Center for Comparative Medicine and Research at The University of Texas MD Anderson Cancer Center. The distinctive feature in these cases, based on PET/computed tomography (CT) imaging, was the presence of two or three tumor lesions in different locations, including proximal to the ileocecal juncture, proximal to the hepatic flexure, and/or in the sigmoid colon. These colon carcinoma lesions selectively accumulated [18F]fluorodeoxyglucose ([18F]FDG) and [18F]fluoroacetate ([18F]FACE) at high levels, reflecting elevated carbohydrate and fatty acid metabolism in these tumors. In contrast, the accumulation of [18F]fluorothymidine ([18F]FLT) was less significant, reflecting slow proliferative activity in these tumors. The diagnoses of colon carcinomas were confirmed by endoscopy. The expression of MLH1, MSH2, and MSH6 proteins and the degree of microsatellite instability (MSI) was assessed in colon carcinomas. The loss of MLH1 protein expression was observed in all tumors and was associated with a deletion mutation in the MLH1 promoter region and/or multiple single-nucleotide polymorphism (SNP) mutations in the MLH1 gene. All tumors exhibited various degrees of MSI. The pedigree analysis of this rhesus macaque population revealed several clusters of affected animals related to each other over several generations, suggesting an autosomal dominant transmission of susceptibility for colon cancer. The newly discovered hereditary nonpolyposis colorectal cancer syndrome in rhesus macaques, termed MLH1-rheMac, may serve as a model for development of novel approaches to diagnosis and therapy of Lynch syndrome in humans.

Phase II, 2-stage, 2-arm, PIK3CA mutation stratified trial of MK-2206 in recurrent endometrial cancer.

Endometrial cancers have high rates of phosphoinositide 3-kinase (PI3K) pathway alterations. MK-2206 is an allosteric inhibitor of AKT, an effector kinase of PI3K signals. We hypothesized patients with tumors harboring PIK3CA mutations would be more likely to benefit from MK-2206 than those without PIK3CA mutation. A Phase II study was performed in patients with recurrent endometrial cancer; all histologies except carcinosarcoma were eligible. Up to two prior chemotherapy lines were permitted, excluding prior treatment with PI3K pathway inhibitors. The first 18 patients were treated with MK-2206 200 mg weekly. Due to unacceptable toxicity, dose was reduced to 135 mg. Co-primary endpoints were objective response rate (ORR) and progression-free survival at 6 months (6moPFS). Thirty-seven patients were enrolled (one ineligible). By somatic PIK3CA mutation analysis, nine patients were mutant (MT) [one with partial response (PR)/6moPFS, two with 6moPFS]. Twenty-seven patients were wild-type (WT) (one PR and four 6moPFS). Most common toxicities were rash (44%), fatigue (41%), nausea (42%) and hyperglycemia (31%). Grade 3 and 4 toxicities occurred in 25 and 17% of patients, respectively. Exploratory analysis found serous histology had greater 6moPFS as compared to all other histologies (5/8 vs. 2/28, p = 0.003). PTEN expression was associated with median time to progression (p = 0.04). No other significant associations with PI3K pathway alterations were identified. There is limited single agent activity of MK-2206 in PIK3CA MT and PIK3CA WT endometrial cancer populations. Activity was detected in patients with serous histology and due to their poor outcomes warrants further study (NCT01307631).

Variable Expression of MSH6 in Endometrial Carcinomas With Intact Mismatch Repair and With MLH1 Loss Due to MLH1 Methylation.

Immunohistochemistry for mismatch repair proteins MLH1, MSH2, MSH6, and PMS2 is an effective screen to detect individuals at risk for Lynch syndrome. College of American Pathologists guidelines stipulate that protein expression should be reported as present versus absent, as most patients with germline mutations in a mismatch repair gene have complete loss of protein expression in tumor cells. A similar approach is employed to screen for cancer patients eligible for immune checkpoint blockade. This "all or none" interpretive approach ignores substantial evidence that mismatch repair may be more finely regulated by other mechanisms. We have observed clinically that MSH6 expression is variable, even in carcinomas that are overall considered positive for MSH6 expression. A proof-of-principle study was therefore designed to more rigorously quantify the protein expression of MSH6 and its binding partner, MSH2, using image analysis applied to age-matched endometrioid grade 2 subsets that were either mismatch repair intact or MLH1-deficient due to MLH1 gene methylation. In both endometrioid groups, MSH6 expression was significantly lower than MSH2 expression. MSH6 expression increased in higher grade, mismatch repair intact serous carcinomas, but it was still significantly lower than that for MSH2. MSH2 expression was consistently high across the 3 different tumor groups. These results suggest that MSH6 expression is subject to wide fluctuations in expression, even when overall its expression is considered intact. While such fluctuations are likely not relevant for Lynch syndrome screening, they may be more impactful when considering patients eligible for immune checkpoint blockade.

The ERM family member Merlin is required for endometrial gland morphogenesis.

Disruption of endometrial gland formation or function can cause female infertility. Formation of endometrial glands via tubulogenesis of luminal epithelial cells requires the establishment and maintenance of cell polarity and cell adhesion. The FERM domain-containing protein Merlin coordinates epithelial cell polarity and cell adhesion and is critical for epithelial tissue function in the skin and kidney. We now demonstrate a requirement for Merlin in endometrial gland development. Conditional deletion of Merlin in the endometrium results in female infertility caused by the absence of gland formation. Interestingly, we observed glandular epithelial markers within discrete groups of cells in the Merlin-deficient luminal epithelium. Wnt signaling, a pathway necessary for endometrial gland development is maintained in Merlin-deficient endometrium, suggesting the glandular fate program is active. Instead, we observe increased levels of apical actin and markers indicative of high membrane tension on the basal surface of the Merlin-deficient luminal epithelium. These findings suggest that the structural integrity of the luminal epithelium during gland formation is required for appropriate endometrial tubulogenesis and tissue function. Moreover, our work implicates Merlin-dependent regulation of mechanical tension in the proper formation of endometrial gland architecture and function.

Targeted next-generation sequencing of endometrial cancer and matched circulating tumor DNA: identification of plasma-based, tumor-associated mutations in early stage patients.

There is currently no blood-based marker in routine use for endometrial cancer patients. Such a marker could potentially be used for early detection, but it could also help to track tumor recurrence following hysterectomy. This is important, as extra-vaginal recurrence of endometrial endometrioid adenocarcinoma is usually incurable. This proof-of-principle study was designed to determine if tumor-associated mutations could be detected in cell-free DNA from the peripheral blood of early and late stage endometrial endometrioid carcinoma patients. Approximately 90% of endometrioid carcinomas have at least one mutation in the genes CTNNB1, KRAS, PTEN, or PIK3CA. Using a custom panel targeting 30 hotspot amplicons in these four genes, next-generation sequencing was performed on cell-free DNA extracted from plasma obtained from a peripheral blood draw at the time of hysterectomy and the matching tumor DNA from 48 patients with endometrioid endometrial carcinomas. At least one mutation in the tumor was detected in 45/48 (94%) of patients. Fifteen of 45 patients (33%) had a mutation in the plasma that matched a mutation in the tumor. These same mutations were not detected in the matched negative control buffy coat. Presence of a plasma mutation was significantly associated with advanced stage at hysterectomy, deep myometrial invasion, lymphatic/vascular invasion, and primary tumor size. Detecting a plasma-based mutation was independent of the amount of cell-free DNA isolated from the plasma. Overall, 18% of early stage patients had a mutation detected in the plasma. These results demonstrate that mutations in genes relevant to endometrial cancer can be identified in the peripheral blood of patients at the time of surgery. Future studies can help to determine the post-operative time course of mutation clearance from the peripheral blood and if mutation re-emergence is predictive of recurrence.

G-protein coupled receptor 64 (GPR64) acts as a tumor suppressor in endometrial cancer.

BACKGROUND: Endometrial cancer is the most common gynecological cancer. G-protein coupled receptor 64 (GPR64) belongs to a family of adhesion GPCRs and plays an important role in male fertility. However, the function of GPR64 has not been studied in endometrial cancer. Our objective is to investigate the role of GPR64 in endometrial cancer. METHODS: We examined the levels of GPR64 in human endometrioid endometrial carcinoma by immunohistochemistry analysis. To determine a tumor suppressor role of GPR64 in endometrial cancer, we used a siRNA loss of function approach in human endometrial adenocarcinoma cell lines. RESULTS: GPR64 levels were remarkably lower in 10 of 21 (47.62%) of endometrial carcinoma samples compared to control. Depletion of GPR64 by siRNA transfection revealed an increase of colony formation ability, cell proliferation, cell migration, and invasion activity in Ishikawa and HEC1A cells. The expression of Connexin 43 (Cx43), a member of the large family of gap junction proteins, was reduced through activation of AMP-activated protein kinase (AMPK) in Ishikawa cells with GPR64-deficicy. CONCLUSIONS: These results suggest that GPR64 plays an important tumor suppressor role in endometrial cancer.

Adjuvant combined-modality therapy for stage IIIC endometrioid and non-endometrioid endometrial cancer.

OBJECTIVE: To identify the optimal adjuvant treatment regimen for patients with endometrioid and non-endometrioid node-positive endometrial cancer. METHODS: We retrospectively identified 249 women with FIGO 2009 stage IIIC endometrial cancer at our institution who underwent surgical staging from 1985 to 2015 followed by external beam radiotherapy (RT), chemotherapy (CT), or a combination of CT + RT. Survival rates were calculated using the Kaplan-Meier method. RESULTS: The 5-year disease-specific survival (DSS) rate for all patients was 65%. Adjuvant CT + RT conferred higher rates of 5-year DSS as compared to CT alone in patients with grade 3 endometrioid and non-endometrioid tumors (61% vs. 27%, P = 0.04 and 67% vs. 38%, P = 0.02, respectively). Among patients with non-endometrioid tumors, treatment with concurrent chemoradiotherapy followed by additional sequential chemotherapy had higher 5-year DSS rates than with concurrent chemoradiotherapy alone (74% vs. 50%, P = 0.02). The 3-year pelvic recurrence rate was 5% with RT ±â€¯CT and 35% with CT alone (P < 0.001) for all patients. No paraaortic nodal failures were observed following extended-field RT, but 14% of patients who received pelvic-only RT or CT alone developed recurrences in the paraaortic nodes (P < 0.001). CONCLUSIONS: Combined-modality therapy including adjuvant external beam pelvic radiotherapy yields excellent outcomes for patients with all subtypes of node-positive endometrial cancer. The most pronounced DSS advantage from adjuvant chemoradiotherapy was evident in women with non-endometrioid endometrial cancer.

Molecular Modifiers of Hormone Receptor Action: Decreased Androgen Receptor Expression in Mismatch Repair Deficient Endometrial Endometrioid Adenocarcinoma.

Endometrial endometrioid carcinoma is related to estrogen excess and expression of estrogen and progesterone receptors. Epidemiological evidence suggests that exposure to elevated androgens, as in polycystic ovarian syndrome, increases the risk of endometrial cancer. Factors impacting androgen receptor (AR) expression are not well studied. Mismatch repair (MMR) deficiency due to MLH1 gene methylation is one of the most common molecular alterations in endometrial cancer, occurring in 15% to 20% of cases. MLH1 methylation can be associated with decreased expression of other genes, so we examined the effect of MMR status on AR expression. As NF-κB is known to induce AR, this transcription factor was also examined. Three hundred forty-four unselected endometrial carcinomas were evaluated for DNA MMR. Loss of expression of MLH1 with MLH1 methylation was defined as MMR deficient, and positive expression of MMR proteins was defined as MMR intact. A case-control cohort of 96 grade 2 endometrioid carcinomas was studied from this set (47 MMR deficient, 49 MMR intact). Cases were matched for histotype, grade, and age. AR and NF-κB immunohistochemical expression were evaluated by 2 different scoring systems (CAP/ASCO and Allred) used for estrogen receptor. Despite higher levels of NF-κB, MMR deficiency was associated with a significantly lower mean percentage of AR expression. The MMR deficient group had more variable AR expression, with more cases scoring on the lower end of the spectrum. These findings have implications for clinical trials of AR antagonists in gynecologic cancers.

Universal Point of Care Testing for Lynch Syndrome in Patients with Upper Tract Urothelial Carcinoma.

PURPOSE: Patients with Lynch syndrome are at risk for upper tract urothelial carcinoma. We sought to identify the incidence and most reliable means of point of care screening for Lynch syndrome in patients with upper tract urothelial carcinoma. MATERIALS AND METHODS: A total of 115 consecutive patients with upper tract urothelial carcinoma without a history of Lynch syndrome were universally screened during followup from January 2013 through July 2016. We evaluated patient and family history using AMS (Amsterdam criteria) I and II, and tumor immunohistochemistry for mismatch repair proteins and microsatellite instability. Patients who were positive for AMS I/II, microsatellite instability or immunohistochemistry were classified as potentially having Lynch syndrome and referred for clinical genetic analysis and counseling. Patients with known Lynch syndrome served as positive controls. RESULTS: Of the 115 patients 16 (13.9%) screened positive for potential Lynch syndrome. Of these patients 7.0% met AMS II criteria, 11.3% had loss of at least 1 mismatch repair protein and 6.0% had high microsatellite instability. All 16 patients were referred for germline testing, 9 completed genetic analysis and counseling, and 6 were confirmed to have Lynch syndrome. All 7 patients with upper tract urothelial carcinoma who had a known history of Lynch syndrome were positive for AMS II criteria and at least a single mismatch repair protein loss while 5 of 6 had high microsatellite instability. CONCLUSIONS: We identified 13.9% of upper tract urothelial carcinoma cases as potential Lynch syndrome and 5.2% as confirmed Lynch syndrome at the point of care. These findings have important implications for universal screening of upper tract urothelial carcinoma, representing one of the highest rates of undiagnosed genetic disease in a urological cancer.

MIG-6 suppresses endometrial epithelial cell proliferation by inhibiting phospho-AKT.

BACKGROUND: Aberrant hyperactivation of epithelial proliferation, AKT signaling, and association with unopposed estrogen (E2) exposure is the most common endometrial cancer dysfunction. In the normal uterus, progesterone (P4) inhibits proliferation by coordinating stromal-epithelial cross-talk, which we previously showed is mediated by the function of Mitogen-inducible gene 6 (Mig-6). Despite their attractive characteristics, non-surgical conservative therapies based on progesterone alone have not been universally successful. One barrier to this success has been the lack of understanding of the P4 effect on endometrial cells. METHOD: To further understand the role of Mig-6 and P4 in controlling uterine proliferation, we developed a Sprr2f-cre driven mouse model where Mig-6 is specifically ablated only in the epithelial cells of the uterus (Sprr2f cre+ Mig-6 f/f ). We examined P4 effect and regulation of AKT signaling in the endometrium of mutant mice. RESULTS: Sprr2f cre+ Mig-6 f/f mice developed endometrial hyperplasia. P4 treatment abated the development of endometrial hyperplasia and restored morphological and histological characteristics of the uterus. P4 treatment reduced cell proliferation which was accompanied by decreased AKT signaling and the restoration of stromal PGR and ESR1 expression. Furthermore, our in vitro studies revealed an inhibitory effect of MIG-6 on AKT phosphorylation as well as MIG-6 and AKT protein interactions. CONCLUSIONS: These data suggest that endometrial epithelial cell proliferation is regulated by P4 mediated Mig-6 inhibition of AKT phosphorylation, uncovering new mechanisms of P4 action. This information may help guide more effective non-surgical interventions in the future.

Somatic mutation profiles of clear cell endometrial tumors revealed by whole exome and targeted gene sequencing.

BACKGROUND: The molecular pathogenesis of clear cell endometrial cancer (CCEC), a tumor type with a relatively unfavorable prognosis, is not well defined. We searched exome-wide for novel somatically mutated genes in CCEC and assessed the mutational spectrum of known and candidate driver genes in a large cohort of cases. METHODS: We conducted whole exome sequencing of paired tumor-normal DNAs from 16 cases of CCEC (12 CCECs and the CCEC components of 4 mixed histology tumors). Twenty-two genes-of-interest were Sanger-sequenced from another 47 cases of CCEC. Microsatellite instability (MSI) and microsatellite stability (MSS) were determined by genotyping 5 mononucleotide repeats. RESULTS: Two tumor exomes had relatively high mutational loads and MSI. The other 14 tumor exomes were MSS and had 236 validated nonsynonymous or splice junction somatic mutations among 222 protein-encoding genes. Among the 63 cases of CCEC in this study, we identified frequent somatic mutations in TP53 (39.7%), PIK3CA (23.8%), PIK3R1 (15.9%), ARID1A (15.9%), PPP2R1A (15.9%), SPOP (14.3%), and TAF1 (9.5%), as well as MSI (11.3%). Five of 8 mutations in TAF1, a gene with no known role in CCEC, localized to the putative histone acetyltransferase domain and included 2 recurrently mutated residues. Based on patterns of MSI and mutations in 7 genes, CCEC subsets molecularly resembled serous endometrial cancer (SEC) or endometrioid endometrial cancer (EEC). CONCLUSION: Our findings demonstrate molecular similarities between CCEC and SEC and EEC and implicate TAF1 as a novel candidate CCEC driver gene. Cancer 2017;123:3261-8. © 2017 American Cancer Society.

CTNNB1 (beta-catenin) mutation identifies low grade, early stage endometrial cancer patients at increased risk of recurrence.

Although the majority of low grade, early stage endometrial cancer patients will have good survival outcomes with surgery alone, those patients who do recur tend to do poorly. Optimal identification of the subset of patients who are at high risk of recurrence and would benefit from adjuvant treatment has been difficult. The purpose of this study was to evaluate the impact of somatic tumor mutation on survival outcomes in this patient population. For this study, low grade was defined as endometrioid FIGO grades 1 or 2, while early stage was defined as endometrioid stages I or II (disease confined to the uterus). Next-generation sequencing was performed using panels comprised of 46-200 genes. Recurrence-free and overall survival was compared across gene mutational status in both univariate and multivariate analyses. In all, 342 patients were identified, 245 of which had endometrioid histology. For grades 1-2, stages I-II endometrioid endometrial cancer patients, age (HR 1.07, 95% CI 1.03-1.10), CTNNB1 mutation (HR 5.97, 95% CI 2.69-13.21), and TP53 mutation (HR 4.07, 95% CI 1.57-10.54) were associated with worse recurrence-free survival on multivariate analysis. When considering endometrioid tumors of all grades and stages, CTNNB1 mutant tumors were associated with significantly higher rates of grades 1-2 disease, lower rates of deep myometrial invasion, and lower rates of lymphatic/vascular space invasion. When both TP53 and CTNNB1 mutations were considered, presence of either TP53 mutation or CTNNB1 mutation remained a statistically significant predictor of recurrence-free survival on multivariate analysis and was associated with a more precise confidence interval (HR 4.69, 95% CI 2.38-9.24). Thus, mutational analysis of a 2 gene panel of CTNNB1 and TP53 can help to identify a subset of low grade, early stage endometrial cancer patients who are at high risk of recurrence.