Lack of an Association between a Polymorphism in the KRAS 3' Untranslated Region (rs61764370) and Endometriosis in a Large European Case-Control Study.

BACKGROUND: Endometriosis is a common disorder that affects 6-10% of reproductive age women. In a previous study, we demonstrated that a polymorphism in let-7 microRNA-binding site in the 3' untranslated region of the KRAS gene was found in 31% of subjects with endometriosis resistant to medical therapy. This polymorphism was now tested in a large, case-control study. METHODS: Peripheral blood or peritoneal biopsies from 2,077 European subjects with or without endometriosis and known infertility were tested for the presence of the variant allele using polymerase chain reaction. RESULTS: Histologically proven endometriosis was found in 1,140 subjects, while 937 subjects were disease free. Variant allele carrier rates in subjects with and without endometriosis were 15.7 and 15.1%, respectively. No association between the variant KRAS allele and stage of the disease, age at surgery, body mass index, or type of infertility was identified. CONCLUSION: A germ-line single-nucleotide polymorphism in the let-7 microRNA-binding site of the KRAS gene was not associated with sporadic endometriosis in an infertile Caucasian population in this large case-control study. However, it remains possible that this gene variant may be a marker of treatment resistance. Further studies on the role of this polymorphism in endometriosis are needed.

Cesarean Scar Pregnancy, Incidence, and Recurrence: Five-Year Experience at a Single Tertiary Care Referral Center.

OBJECTIVE: To describe the treatment and subsequent pregnancy outcomes in patients with cesarean scar pregnancies at a single institution over 5 years. METHODS: This is a case series of all cesarean scar pregnancies diagnosed from May 2013 to March 2018 at Yale-New Haven Hospital. Data were collected on each patient using electronic medical record review and included patient demographics; medical, surgical, and obstetric history; pregnancy characteristics; treatment modalities used; response to therapy; complications; and subsequent pregnancy outcomes. RESULTS: Thirty cases of cesarean scar pregnancies were diagnosed in 26 patients, including one recurrence in one patient and three recurrences in another. Forty-six percent of cesarean scar pregnancies were in Hispanic women. The median number of prior cesarean deliveries was two. Mean gestational age at the time of diagnosis was 46 days (SD±10). Fetal cardiac activity was detected in 18 cases. Three patients initially were erroneously diagnosed with a viable intrauterine pregnancy and failed medical termination. Others opted for termination through systemic methotrexate alone (n=4), systemic and local methotrexate (n=12), systemic and local methotrexate with potassium chloride injected into the gestational sac (n=3), potassium chloride injection with laparotomy and wedge resection (n=1), methotrexate with bilateral uterine artery embolization (n=2), or intrauterine balloon (n=4). Five patients who underwent expectant management or methotrexate therapy had retained products of conception and required hysteroscopy and curettage. One patient opted for hysterectomy after failed curettage. After complete resolution of cesarean scar pregnancies, there were 10 subsequent spontaneous conceptions in eight patients, including four recurrent cesarean scar pregnancies, four term pregnancies, and one spontaneous abortion. One viable normally located pregnancy is ongoing. CONCLUSION: There is a wide array of treatment modalities available for cesarean scar pregnancies. Women with a cesarean scar pregnancy are at risk for its recurrence in the future, although normal pregnancy after a cesarean scar pregnancy is also possible. Safe outcomes depend on timely diagnosis and multidisciplinary care by skilled clinicians.

Endometrial Carcinoma in a 26-Year-Old Patient with Bardet-Biedl Syndrome.

BACKGROUND: Bardet-Biedl Syndrome (BBS) is a rare genetic condition characterized by cognitive impairment, dysmorphism, central obesity, and diabetes mellitus, among other abnormalities. Although some of these characteristics are known independent risk factors for endometrial cancer and its precursors, the association between BBS and endometrial cancer is underreported. CASE: We present the case of a 26-year-old patient with BBS and clinical signs of hyperestrogenism who presented with abnormal uterine bleeding and was diagnosed with endometrioid adenocarcinoma. She ultimately underwent definitive surgical treatment with hysterectomy and bilateral salpingectomy. CONCLUSIONS: This is one of only a few reports in the literature describing the association of BBS and endometrioid endometrial adenocarcinoma. Given the association of BBS with risk factors for hyperestrogenism such as truncal obesity, hyperinsulinemia, and ovulatory dysfunction, providers should have increased suspicion for endometrial cancer in young patients with BBS and abnormal uterine bleeding.

Global gene expression profiling of proliferative phase endometrium reveals distinct functional subdivisions.

The human endometrium follows a predictable pattern of development during the proliferative phase. Endometrial thickness increases after day 3 and then plateaus at days 9 to 10 of the menstrual cycle despite continued high serum levels of estrogen. We hypothesized that proliferative phase endometrium undergoes more than simple estrogen responsive growth, rather it is characterized by complex time-dependent functional activities reflected in differential gene expression. Nine endometrial RNA samples from healthy participants were subjected to microarray analysis and 15 samples were used for quantitative real-time polymerase chain reaction. The samples were divided into early, mid, or late proliferative phase. The early proliferative phase showed higher expression of genes including transforming growth factor ß2, chemokine (C-C motif) ligand 18 (CCL18), and metallothionein 2A. The mid-proliferative phase was characterized by higher expression of heat shock proteins and implantation-associated genes including Indian hedgehog, secreted frizzled protein 4, and progesterone receptor. In the late proliferative phase, we identified increased angiotensin II receptor, type 2 and large decrease in expression of genes related to natural killer (NK) cell function. We demonstrate a unique gene expression signature at distinct time points within the proliferative phase. The early proliferative phase is characterized by tissue remodeling, angiogenesis, and modulation of inflammation; the mid-proliferative phase is characterized not only by proliferation in response to estrogens but also marks the onset of expression of genes required for endometrial receptivity and a dampening of estrogen responsiveness. In the late proliferative phase, changes in immune function and NK cells predominate. The proliferative phase is not simply a uniform period of estrogen responsive endometrial growth that can be considered as a single experimental time point when evaluating endometrial development; rather the proliferative phase is complex with differing functions and patterns of gene expression.

A polymorphism in a let-7 microRNA binding site of KRAS in women with endometriosis.

Endometriosis is found in 5-15% of women of reproductive age and is more frequent in relatives of women with the disease. Activation of KRAS results in de novo endometriosis in mice, however, activating KRAS mutations have not been identified in women. We screened 150 women with endometriosis for a polymorphism in a let-7 microRNA (miRNA) binding site in the 3'-UTR of KRAS and detected a KRAS variant allele in 31% of women with endometriosis as opposed to 5% of a large diverse control population. KRAS mRNA and protein expression were increased in cultured endometrial stromal cells of women with the KRAS variant. Increased KRAS protein was due to altered miRNA binding as demonstrated in reporter assays. Endometrial stromal cells from women with the KRAS variant showed increased proliferation and invasion. In a murine model, endometrial xenografts containing the KRAS variant demonstrated increased proliferation and decreased progesterone receptor levels. These findings suggest that an inherited polymorphism of a let-7 miRNA binding site in KRAS leads to abnormal endometrial growth and endometriosis. The LCS6 polymorphism is the first described genetic marker of endometriosis risk.

MicroRNA 135 regulates HOXA10 expression in endometriosis.

CONTEXT: Homeo box A10 (HOXA10) regulates endometrial receptivity and its expression is decreased in women with endometriosis. Although sex steroids regulate HOXA10, these hormones are unaltered in endometriosis. We hypothesized a role for microRNA in the regulation of HOXA10. OBJECTIVE: MicroRNA 135a and -b are small noncoding RNA with predicted targets that include HOXA10. We evaluated miR135a/b expression and HOXA10 regulation in endometrium from subjects with and without endometriosis. DESIGN: The design of the study was the measurement of miR135a/b expression by quantitative PCR and in vitro analysis of HOXA10 regulation. SETTING: The study was conducted at a university medical center. PATIENTS: Patients included 50 controls and 32 women with endometriosis. INTERVENTIONS: Study interventions included endometrial biopsies and in vitro transfection. MAIN OUTCOME MEASURES: miR135a/b and HOXA10 expression were measured in the study. RESULTS: All endometrial samples expressed miR135a and -b. miR135a expression in controls was increased during the proliferative phase, decreased at the time of ovulation, and increased during the luteal phase. Subjects with endometriosis had 3-fold higher expression of miR135a in the proliferative phase than controls. miR135b showed less variation across the menstrual cycle; however, it was significantly increased in women with endometriosis in the proliferative and secretory phases. HOXA10 expression was simultaneously repressed in the endometrium of women with endometriosis. Transfection of endometrial stromal cells with mir135a/b or miR135a/b inhibitors resulted in the altered expression of HOXA10 mRNA and protein. miR135a or -b decreased luciferase expression driven by the HOXA10 3' untranslated region containing the miR135 binding site. miR135a regulation of HOXA10 was absent in MCF-7 cells, demonstrating cell specificity. CONCLUSIONS: HOXA10 was aberrantly regulated in the endometrium of women with endometriosis by both miR135a and miR135b. Increased microRNA expression likely suppresses genes required for implantation.