Histopathology of endometrial hyperplasia and endometrial carcinoma: an update

Clinical translation of metabolomics markers in endometrial carcinoma

OBJECTIVE

This comprehensive review highlights the current research on metabolomics and the metabolic pathways involved in endometrial cancer (EC), offering potential non-invasive biomarkers for EC.

METHODS

The data was extracted from published manuscripts between 2015 and 2024 using the reputed search engine "Pubmed." All gathered data were organized into a single table, facilitating a comparison with earlier findings.

RESULTS

The results of this study revealed most metabolites identified in previous metabolomic research on EC are associated with lipid, glucose, and amino acid metabolism.

CONCLUSION

Therefore, understanding these metabolic pathway alterations in EC is crucial for improving diagnosis, prognosis, and treatments by specially targeting these metabolic pathways.

Potential Benefits of Adding Alendronate, Celecoxib, Itraconazole, Ramelteon, and Simvastatin to Endometrial Cancer Treatment: The EC5 Regimen

Metastatic endometrial cancer continues to be a common cause of death as of 2024, even after maximal use of all currently available standard treatments. To address this problem of metastatic cancer generally in 2025, the drug repurposing movement within oncology identifies medicines in common general medical use that have clinical or preclinical experimental data indicating that they interfere with or inhibit a specific growth driving element identified in a given cancer. The drug repurposing movement within oncology also uses data from large scale in vitro screens of thousands of drugs, looking for simple empirical growth inhibition in a given cancer type. This paper outlines the data showing that five drugs from general medical practice meet these evidence criteria for inhibition of endometrial cancer growth, the EC5 regimen. The EC5 regimen uses the osteoporosis treatment drug, alendronate; the analgesic drug, celecoxib; the antifungal drug, itraconazole; the sleep aid, ramelteon; and the cholesterol lowering drug, simvastatin. Side effects seen with these drugs are usually minimal and easily tolerated by patients.

Association between metabolic disorders and clinicopathologic features in endometrial cancer

Background

In recent years, the incidence of Endometrial cancer (EC) has been on the rise due to high-fat, high-calorie diets and low-exercise lifestyles. However, the relationships between metabolic disorders and the progression of EC remain uncertain. The purpose of our study was to explore the potential association between obesity, hypertension, hyperglycemia and clinicopathologic characteristics in EC patients.

Methods

In categorical variables, Chi-square tests were used to calculate P values. Univariate logistic regression and multivariate logistic regression were used to identify the risk factors of myometrial invasion>1/2 and lymph node metastasis. Overall survival (OS) was estimated using the Kaplan-Meier method.

Results

The study included 406 individuals with EC, 62.6% had type I and 37.4% had type II. Hypertension was seen in 132 (32.5%), hyperglycemia in 75 (18.5%), and overweight or obesity in 217 (53.4%). Hypertension, hyperglycemia, and obesity are strongly associated with the clinicopathologic features of EC. Multivariate logistic regression revealed that hyperglycemia (OR=2.439,95% CI: 1.025-5.804, P = 0.044) was a risk factor for myometrial invasion depth >1/2 in patients with type I EC, and hypertension (OR=32.124,95% CI: 3.287-313.992, P = 0.003) was a risk factor for lymph node metastasis in patients with type I EC. Survival analysis found that hyperglycemia (P < 0.001) and hypertension (P = 0.002) were associated with OS in type I EC. Neither hyperglycemia, hypertension, nor obesity were associated with the prognosis in type II EC.

Conclusion

Hyperglycemia was a risk factor for myometrial invasion depth >1/2 in patients with type I EC and hypertension was a risk factor for lymph node metastasis in patients with type I EC. Hypertension and hyperglycemia were associated with poor prognosis in patients with type I EC.

Endometrial Adenocarcinoma in Young Women: A Case Report and Review of Literature

Endometrial cancer in young women presents a unique challenge to care teams. With over 90% of cases diagnosed in women over the age of 50, its diagnosis can be delayed in younger patients if the medical team does not maintain a high enough index of suspicion. Once diagnosed, treatment options depend on a desire to maintain fertility. We present a case of a 36-year-old female who, following cross-sectional imaging and pathological analysis, was diagnosed with endometrioid endometrial adenocarcinoma. This case explores the epidemiology of endometrial cancer in young women and the importance of a multi-disciplinary approach to the diagnosis and treatment of this rare malignancy.

Overall survival prediction models for gynecological endometrioid adenocarcinoma with squamous differentiation (GE-ASqD) using machine-learning algorithms

The actual 5-year survival rates for Gynecological Endometrioid Adenocarcinoma with Squamous Differentiation (GE-ASqD) are rarely reported. The purpose of this study was to evaluate how histological subtypes affected long-term survivors of GE-ASqD (> 5 years). We conducted a retrospective analysis of patients diagnosed GE-ASqD from the Surveillance, Epidemiology, and End Results database (2004-2015). In order to conduct the studies, we employed the chi-square test, univariate cox regression, and multivariate cox proportional hazards model. A total of 1131 patients with GE-ASqD were included in the survival study from 2004 to 2015 after applying the inclusion and exclusion criteria and the sample randomly split into a training set and a test set at a ratio of 7:3. Five machine learning algorithms were trained based on nine clinical variables to predict the 5-year overall survival. The AUC of the training group for the LR, Decision Tree, forest, Gbdt, and gbm algorithms were 0.809, 0.336, 0.841, 0.823, and 0.856 respectively. The AUC of the testing group was 0.779, 0.738, 0.753, 0.767 and 0.734, respectively. The calibration curves confirmed good performance of the five machine learning algorithms. Finally, five algorithms were combined to create a machine learning model that forecasts the 5-year overall survival rate of patients with GE-ASqD.

Single-cell transcriptomic analysis highlights origin and pathological process of human endometrioid endometrial carcinoma

Endometrial cancers are complex ecosystems composed of cells with distinct phenotypes, genotypes, and epigenetic states. Current models do not adequately reflect oncogenic origin and pathological progression in patients. Here we use single-cell RNA sequencing to profile cells from normal endometrium, atypical endometrial hyperplasia, and endometrioid endometrial cancer (EEC), which altogether represent the step-by-step development of endometrial cancer. We find that EEC originates from endometrial epithelial cells but not stromal cells, and unciliated glandular epithelium is the source of EEC. We also identify LCN2 + /SAA1/2 + cells as a featured subpopulation of endometrial tumorigenesis. Finally, the stromal niche and immune environment changes during EEC progression are described. This study elucidates the evolution of cell populations in EEC development at single-cell resolution, which would provide a direction to facilitate EEC research and diagnosis.

Metastatic endometrioid carcinoma in a hybrid Leontopithecus sp

Primary female reproductive neoplasms in Platyrrhines species are few reported. We present the gross, histological, and immunohistochemical findings of metastatic endometrioid carcinoma in the uterus, urinary bladder, jejunum, and rectum of a Leontopithecus sp. The neoplastic endometrial cells expressed strong cytoplasmic immunolabeling of cytokeratin 7.

EZH2 and Endometrial Cancer Development: Insights from a Mouse Model

Enhancer of zeste homolog 2 (EZH2), a core component of polycomb repressive complex 2, plays an important role in cancer development. As both oncogenic and tumor suppressive functions of EZH2 have been documented in the literature, the objective of this study is to determine the impact of Ezh2 deletion on the development and progression of endometrial cancer induced by inactivation of phosphatase and tensin homolog (PTEN), a tumor suppressor gene frequently dysregulated in endometrial cancer patients. To this end, we created mice harboring uterine deletion of both Ezh2 and Pten using Cre recombinase driven by the progesterone receptor (Pgr) promoter. Our results showed reduced tumor burden in Pten^d/d; Ezh2^d/d mice compared with that of Pten^d/d mice during early carcinogenesis. The decreased Ki67 index in EZH2 and PTEN-depleted uteri versus that in PTEN-depleted uteri indicated an oncogenic role of EZH2 during early tumor development. However, mice harboring uterine deletion of both Ezh2 and Pten developed unfavorable disease outcome, accompanied by exacerbated epithelial stratification and heightened inflammatory response. The observed effect was non-cell autonomous and mediated by altered immune response evidenced by massive accumulation of intraluminal neutrophils, a hallmark of endometrial carcinoma in Pten^d/d; Ezh2^d/d mice during disease progression. Hence, these results reveal dual roles of EZH2 in endometrial cancer development.

Genomic mutation features identify distinct BRCA-associated mutation characteristics in endometrioid carcinoma and endometrioid ovarian carcinoma

Although endometrioid carcinoma (EC) and endometrioid ovarian carcinoma (EnOC) display similar pathological features, their molecular characteristics remain to be determined. Somatic mutation data from 2777 EC, 423 EnOC, and 57 endometriosis patients from the Catalogue of Somatic Mutations in Cancer (COSMIC) dataset were analyzed and showed similar profiles with different mutation frequencies among them. By using 275 overlapping mutated genes, EC was clustered into two groups with different disease outcomes and different clinical characteristics. Although BRCA-associated mutation characteristics were identified in both EC and EnOC, the mutation frequencies of BRCA1 (P=0.0146), BRCA2 (P=0.0321), ATR (P=3.25E-11), RAD51 (P=3.95E-08), RAD1 (P=0.0003), TP53 (P=6.11E-33), and BRIP1 (P=2.90E-09) were higher in EnOC. Further analysis showed that EnOC cell lines with BRCA-associated mutation characteristics were more sensitive to poly ADP-ribose polymerase (PARP) inhibitors than EC cell lines, including olaparib, talazoparib, rucaparib, and veliparib. Moreover, based on BRCA-associated mutational and transcriptomic profiles, EC with BRCA-associated mutational burdens shows lower levels of immune cell infiltration, higher expression of immunosuppressive checkpoint molecules and worse prognosis than EC without BRCA mutation. Our study comprehensively analyzed the genome mutation features of EC and EnOC and provide insights into the molecular characteristics of EC and EnOC.

An enormous pelvic tumor in a 46-year-old woman with an elevated serum CA 125 level, what lies beneath it? Investigation of uterine tumors in postmenopausal women

Abdominal and pelvic pain with an associated pelvic mass is a very common emergency situation. There is always a management dilemma for most emergency physicians regarding these patients. A 46-year-old postmenopausal woman was admitted to our emergency department (ED) with complaints of massive abdominal distention. Abdominal and pelvis magnetic resonance imaging (MRI) was performed, which revealed a huge pelvic abdominal mass. All tumor markers were within normal limits. However, the ovarian cancer antigen (CA 125) level was elevated. As there was a strong suspicion of malignancy, the patient underwent total abdominal hysterectomy with bilateral salpingo-oophorectomy. Her final histopathology report was suggestive of uterine leiomyoma. Uterine leiomyomas are the most common benign uterine tumors in women. Surgical treatment is the gold standard, especially for older women with severe symptoms and no desire for future fertility. Although the combination of a pelvic tumor and a high-level of CA 125 arouses suspicion of gynecological malignancy, other benign conditions should always be considered in the differential diagnosis. There is limited evidence to support an association between elevated CA 125 levels and uterine fibroids so far. However, conditions such as the coexistence of adenomyosis and tumor size can affect the level of this marker in uterine fibroids.

IL-37bΔ1-45 suppresses the migration and invasion of endometrial cancer cells by targeting the Rac1/NF-κB/MMP2 signal pathway

Endometrial carcinoma is one of the most common malignancies in the female reproductive system. Interleukin-37 (IL-37) is a newly discovered anti-inflammatory factor belonging to the IL-1 family. IL-37 has five different isoforms, and IL-37b is the most biologically functional subtype. In recent years, the protective roles of IL-37 in different cancers, including lung and liver cancers, have been successively reported. IL-37 also plays an important role in some gynecological diseases such as endometriosis, adenomyosis, and cervical cancer. However, the role and mechanism of IL-37b, especially the mature form of IL-37b, in endometrial carcinoma have not been elucidated. The present study demonstrated that IL-37 protein was downregulated in endometrial carcinoma cells compared with the control endometrium. IL-37b did not affect the proliferation and colony-forming ability of endometrial cancer cells. A mature form of IL-37b (IL-37bΔ1-45) effectively suppressed the migration and invasion of endometrial cancer cells by decreasing the expression of matrix metalloproteinase 2 (MMP2) via Rac1/NF-κB signal pathway. However, it did not affect epithelial-mesenchymal transition (EMT) or filamentous actin (F-actin) depolymerization of endometrial cancer cells. IL-37bΔ1-45 attenuated tumor metastasis in a peritoneal metastatic xenograft model of endometrial cancer. To sum up, these results suggested IL-37b could be involved in the pathogenesis of endometrial carcinoma and provide a novel target for the diagnosis and treatment of endometrial carcinoma.

A Narrative Review of the Role of Diet and Lifestyle Factors in the Development and Prevention of Endometrial Cancer

Simple Summary

The incidence and prevalence of endometrial cancer is increasing globally. The main factors involved in this increase have been the way women live today and what they eat and drink. In fact, the obesity pandemic that is sweeping across the planet is considered to be the main contributory feature. This review aims to introduce to a new audience, those that are not experts in the field, what is known about the different types of endometrial cancer and the mechanisms for their induction and protection. We also seek to summarise the existing knowledge on dietary and lifestyle factors that prevent endometrial development in susceptible populations and identify the main problem in this arena; the paucity of research studies and clinical trials that investigate the interaction(s) between diet, lifestyle and endometrial cancer risk whilst highlighting those areas of promise that should be further investigated.

Abstract

Endometrial cancer is the most common cancer affecting the reproductive organs of women living in higher-income countries. Apart from hormonal influences and genetic predisposition, obesity and metabolic syndrome are increasingly recognised as major factors in endometrial cancer risk, due to changes in lifestyle and diet, whereby high glycaemic index and lipid deposition are prevalent. This is especially true in countries where micronutrients, such as vitamins and minerals are exchanged for high calorific diets and a sedentary lifestyle. In this review, we will survey the currently known lifestyle factors, dietary requirements and hormonal changes that increase an individual’s risk for endometrial cancer and discuss their relevance for clinical management. We also examine the evidence that everyday factors and clinical interventions have on reducing that risk, such that informed healthy choices can be made. In this narrative review, we thus summarise the dietary and lifestyle factors that promote and prevent the incidence of endometrial cancer.

Molecular characterization of Wdr13 knockout female mice uteri: a model for human endometrial hyperplasia

Endometrial hyperplasia (EH) is a condition where uterine endometrial glands show excessive proliferation of epithelial cells that may subsequently progress into endometrial cancer (EC). Modern lifestyle disorders such as obesity, hormonal changes and hyperinsulinemia are known risk factors for EH. A mouse strain that mimics most of these risk factors would be an ideal model to study the stage-wise progression of EH disease and develop suitable treatment strategies. Wdr13, an X-linked gene, is evolutionarily conserved and expressed in several tissues including uteri. In the present study, Wdr13 knockout female mice developed benign proliferative epithelium that progressed into EH at around one year of age accompanied by an increase in body weight and elevated estradiol levels. Molecular characterization studies revealed increase in ERα, PI3K and a decrease in PAX2 and ERβ proteins in Wdr13 mutant mice uteri. Further, a decrease in the mRNA levels of cell cycle inhibitors, namely; p21 and cyclin G2 was seen. Leukocyte infiltration was observed in the uterine tissue of knockout mice at around 12 months of age. These physiological, molecular and pathological patterns were similar to those routinely seen in human EH disease and demonstrated the importance of WDR13 in mice uterine tissue. Thus, the genetic loss of Wdr13 in these mice led to mimicking of the human EH associated metabolic disorders making Wdr13 knockout female mice a potential animal model to study human endometrial hyperplasia.

Prediction of tumor grade and lymphovascular space invasion in endometrial adenocarcinoma with MR imaging-based radiomic analysis

PURPOSE

To evaluate the capabilities of two-dimensional magnetic resonance imaging (MRI)-based texture analysis features, tumor volume, tumor short axis and apparent diffusion coefficient (ADC) in predicting histopathological high-grade and lymphovascular space invasion (LVSI) in endometrial adenocarcinoma.

MATERIALS AND METHODS

Seventy-three women (mean age: 66±11.5 [SD] years; range: 45-88 years) with endometrial adenocarcinoma who underwent MRI of the pelvis at 1.5-T before hysterectomy were retrospectively included. Texture analysis was performed using TexRAD® software on T2-weighted images and ADC maps. Primary outcomes were high-grade and LVSI prediction using histopathological analysis as standard of reference. After data reduction using ascending hierarchical classification analysis, a predictive model was obtained by stepwise multivariate logistic regression and performances were assessed using cross-validated receiver operator curve (ROC).

RESULTS

A total of 72 texture features per tumor were computed. Texture model yielded 52% sensitivity and 75% specificity for the diagnosis of high-grade tumor (areas under ROC curve [AUC]=0.64) and 71% sensitivity and 59% specificity for the diagnosis of LVSI (AUC=0.59). Volumes and tumor short axis were greater for high-grade tumors (P=0.0002 and P=0.004, respectively) and for patients with LVSI (P=0.004 and P=0.0279, respectively). No differences in ADC values were found between high-grade and low-grade tumors and for LVSI. A tumor short axis≥20mm yielded 95% sensitivity and 75% specificity for the diagnosis of high-grade tumor (AUC=0.86).

CONCLUSION

MRI-based texture analysis is of limited value to predict high grade and LVSI of endometrial adenocarcinoma. A tumor short axis≥20mm is the best predictor of high grade and LVSI.

Pyruvate Kinase M2 Expression: A Potential Metabolic Biomarker to Differentiate Endometrial Precancer and Cancer That Is Associated with Poor Outcomes in Endometrial Carcinoma

Background: Pyruvate kinase M2 (PKM2) is a regulator of the processes of glycolysis and oxidative phosphorylation, but the roles that it plays in endometrial cancer remain largely unknown. This study evaluated the PKM2 expression in normal endometrium, endometrial hyperplasia, and endometrial carcinoma, and its prognostic value was investigated in endometrial carcinoma patients. Methods: A hospital-based retrospective review was conducted to examine the immunohistochemical PKM2 distribution in 206 endometrium samples from biopsies or hysterectomies. The immunoreactivity of PKM2 was divided into groups of low and high scores according to the extent and intensity of staining. Results: Intense cytoplasmic staining was observed for the PKM2 protein in malignant endometrial lesions. A high PKM2 score was observed in many endometrial carcinoma samples (50.0%), but there was a low percentage in endometrial atypical hyperplasia (12.5%). High PKM2 expression was not found in the normal endometrium (0.0%) nor endometrial hyperplasia without atypia (0.0%). The PKM2 protein score was significantly higher in endometrial carcinoma samples than premalignant endometrial lesions (p < 0.001). Notably, higher PKM2 scores in cases of endometrial carcinoma correlated with poor overall survival (p = 0.006), and the hazard ratio for death was 3.40 (95% confidence interval, 1.35–8.56). Conclusions: Our results indicate that the prevalence of PKM2^high tumor cells in endometrial carcinoma is significantly associated with worse prognostic factors and favors a poor prognosis. The expression of PKM2 is also a potential histopathological biomarker for use in the differential diagnosis of malignant and premalignant endometrial lesions.

Computer-Aided Diagnosis in Histopathological Images of the Endometrium Using a Convolutional Neural Network and Attention Mechanisms

Uterine cancer (also known as endometrial cancer) can seriously affect the female reproductive system, and histopathological image analysis is the gold standard for diagnosing endometrial cancer. Due to the limited ability to model the complicated relationships between histopathological images and their interpretations, existing computer-aided diagnosis (CAD) approaches using traditional machine learning algorithms often failed to achieve satisfying results. In this study, we develop a CAD approach based on a convolutional neural network (CNN) and attention mechanisms, called HIENet. In the ten-fold cross-validation on ∼3,300 hematoxylin and eosin (H&E) image patches from ∼500 endometrial specimens, HIENet achieved a 76.91 ± 1.17% (mean ± s. d.) accuracy for four classes of endometrial tissue, i.e., normal endometrium, endometrial polyp, endometrial hyperplasia, and endometrial adenocarcinoma. Also, HIENet obtained an area-under-the-curve (AUC) of 0.9579 ± 0.0103 with an 81.04 ± 3.87% sensitivity and 94.78 ± 0.87% specificity in a binary classification task that detected endometrioid adenocarcinoma. Besides, in the external validation on 200 H&E image patches from 50 randomly-selected female patients, HIENet achieved an 84.50% accuracy in the four-class classification task, as well as an AUC of 0.9829 with a 77.97% (95% confidence interval, CI, 65.27%∼87.71%) sensitivity and 100% (95% CI, 97.42%∼100.00%) specificity. The proposed CAD method outperformed three human experts and five CNN-based classifiers regarding overall classification performance. It was also able to provide pathologists better interpretability of diagnoses by highlighting the histopathological correlations of local pixel-level image features to morphological characteristics of endometrial tissue.

High Expression of Galectin-1, VEGF and Increased Microvessel Density Are Associated with MELF Pattern in Stage I-III Endometrioid Endometrial Adenocarcinoma

Background

In this study, we investigate the expression of markers of angiogenesis and microvessel density (MVD) in cases of microcystic, elongated and fragmented (MELF) pattern, with its prognostic role in the survival of endometrioid endometrial adenocarcinomas (EA) patients.

Methods

In this study, 100 cases of EA, 49 cases with MELF pattern and 51 without, were immunohistochemically stained for galectin-1, vascular endothelial growth factor (VEGF), and MVD. Morphometry and statistical (univariate and multivariate) analyses were performed to assess overall survival (OS) and disease-free survival.

Results

The expression of VEGF (p<.001) and galectin-1 (p<.001), as well as MVD area (p<.001) and number of vessels/mm² (p<.050), were significantly higher in the +MELF pattern group compared to the –MELF group. A low negative correlation between MELF-pattern and the number of days of survival (p<.001, r=–0.47) was also found. A low positive correlation of MELF-pattern with galectin-1 expression (p<.001, r=0.39), area of vessels/mm² (p<.001, r=0.36), outcome of EA (p<.001, r=0.42) and VEGF expression (p<.001, r=0.39) suggests potential pathological relevance of these factors in the prognosis of EA. A univariate survival analysis indicated a role for all parameters of survival. Multivariate Cox proportional hazard regression analysis revealed that only area of vessels/mm² (hazard ratio [HR], 1.018; 95% confidence interval [CI], 1.002 to 1.033), galectin-1 (HR, 1.049; 95% CI, 1.025 to 1.074) and VEGF (HR, 1.049; 95% CI, 1.022 to 1.077) play key roles in OS.

Conclusions

This study reports an increase in MVD, VEGF and galectin-1 expression in EA with MELF pattern and suggests that MELF pattern, along with the angiogenic profile, may be a prognostic factor in EA.

Fertility outcomes in infertile women with complex hyperplasia or complex atypical hyperplasia who received progestin therapy and in vitro fertilization

This study aimed to evaluate fertility and oncologic outcomes in women with complex hyperplasia (CH) or complex atypical hyperplasia (CAH) who received fertility-sparing therapy and in vitro fertilization (IVF). Endometrial carcinoma is the most common carcinoma of the female genital tract, and is associated with endometrial hyperplasia (EH) resulting from long-term unopposed estrogenic stimulation of the endometrium. EH is characterized by non-physiological proliferation of endometrium that results in glands with irregular shapes and varying sizes. The World Health Organization (WHO) classified it into four types: simple or complex hyperplasia with or without atypia. CH is characterized by glands with irregular outlines that demonstrate marked structural complexity and back-to-back crowding. Atypical hyperplasia designates a proliferation of glands exhibiting cytologic atypia, in which varying degrees of nuclear atypia and loss of polarity are present. It has been reported that high-dose progestin is safe and efficient for CAH or early-stage low-grade carcinoma for young women who desire fertility-preserving treatment. However, few studies have reported the differences of pregnancy outcomes between patients with CAH and CH, while those patients take a great proportion in people suffered from infertility. More studies about the outcome of IVF are needed. Our aim is to evaluate fertility and oncological outcomes in women with CH or CAH who received fertility-sparing therapy.

The regulation of Hh/Gli1 signaling cascade involves Gsk3β- mediated mechanism in estrogen-derived endometrial hyperplasia

The present study was undertaken to explore the functional involvement of Hh signaling and its regulatory mechanism in endometrial hyperplasia. Differential expression of Hh signaling molecules i.e., Ihh, Shh, Gli1 or Gsk3β was observed in endometrial hyperplasial (EH) cells as compared to normal endometrial cells. Estradiol induced the expression of Hh signaling molecules and attenuated the expression of Gsk3β whereas anti-estrogen (K1) or progestin (MPA) suppressed these effects in EH cells. Cyclopamine treatment or Gli1 siRNA knockdown suppressed the growth of EH cells and reduced the expression of proliferative markers. Estradiol also induced the nuclear translocation of Gli1 which was suppressed by both MPA and K1 in EH cells. While exploring non-canonical mechanism, LY-294002 (Gsk3β activator) caused a decrease in Gli1 expression indicating the involvement of Gsk3β in Gli1 regulation. Further, Gsk3β silencing promoted the expression and nuclear translocation of Gli1 demonstrating that Gsk3β serves as a negative kinase regulator of Gli1 in EH cells. Similar attenuation of Hh signaling molecules was observed in rats with uterine hyperplasia undergoing anti-estrogen treatment. The study suggested that Hh/Gli1 cascade (canonical pathway) as well as Gsk3β-Gli1 crosstalk (non-canonical pathway) play crucial role in estrogen-dependent cell proliferation in endometrial hyperplasia.

Endometrial adenocarcinoma with choriocarcinomatous differentiation in the uterus of a goat

An 11-year-old female goat had invasive and metastatic endometrial adenocarcinoma in the uterus. There was a notable proliferation of endometrial epithelial cells in a tubular growth pattern, with a desmoplastic response. The endometrial epithelial tumor cells metastasized to the kidney, liver and lung. In contrast to the primary and metastatic tumor cells, pleomorphic tumor cells with a choriocarcinoma-like growth pattern infiltrated the mesometrium. Cell proliferation activity was high in both types of tumor cells. Both types of tumor cells expressed cytokeratins AE1/AE3, 7 and CAM5.2; choriocarcinomatous cells also had positive immunoreactions to human chorionic gonadotropin, human placental alkaline phosphatase and α-inhibin. The present case was diagnosed as endometrial adenocarcinoma with choriocarcinomatous differentiation.

Changes of The Uterine Tissue in Rats with Polycystic Ovary Syndrome Induced by Estradiol Valerate

Background

Polycystic ovary syndrome (PCOS) is one of the most common hormonal disorders that can lead to irregular menstrual cycles and hyperandrogenism. Reduced levels of progesterone and increased estrogen in these women can perpetually stimulate the endometrial tissue of the uterus. In this study, we assess the effect of PCOS induction by estradiol valerate (EV) in a rat model.

Materials and Methods

In this experimental study, adult female Wistar rats that weighed approximately 200 g were divided into control, sham, and experimental groups (n=6 per group). The experimental group received subcutaneous injections of 2 mg EV for induction of PCOS. We confirmed the presence of PCOS in the experimental group rats. Rats from all groups were subsequently killed, after which their uteri were removed and fixed for histological and cytological analyses. The uterine tissue sections were stained with hematoxylin and eosin (H&E) and iron hematoxylin (iron-H). We examined epithelium height, thickness of the uterus wall, and frequency of the mitotic cells. The data were assessed at α=0.05.

Results

Uterine tissue findings from the experimental group showed significant increases in the height of the uterus luminal epithelium, the thickness of the uterus wall, and the frequency of eosinophils in the endometrial stroma. We observed an increased frequency of mitotic cells in the experimental group in both luminal and glandular epithelia of the uterus. An increased rate of the glandular epithelium region was noticeable and significant.

Conclusion

Induction of PCOS by EV could change the proliferation rate in the endo- metrial tissue of the uterus.

The reduced PDCD5 protein is correlated with the degree of tumor differentiation in endometrioid endometrial carcinoma

Endometrial cancer is one of the most common malignancies in the female genital tract. Programmed cell death 5 (PDCD5) is a newly identified apoptosis related gene and plays an important role in the development of some human tumors. However, the expression and clinical significance of PDCD5 in endometrial cancer have not been fully elucidated. Here, we evaluated the expression of PDCD5 in endometrioid endometrial carcinoma and control endometrium by qRT-PCR, western blot and immunohistochemistry, and analyzed the associations of PDCD5 expression with clinicopathological parameters of patients. In addition, we detected the expression of PDCD5 in control endometrial glandular epithelial cells and endometrioid endometrial carcinoma-derived cell line KLE by immunocytochemistry. The results showed that PDCD5 protein mainly expressed in the cytoplasm of glandular epithelial cells and endometrial carcinoma cells, and there was a low level of PDCD5 expression in the nuclei of the above cells. Furthermore, PDCD5 protein level was significantly lower in endometrial carcinoma samples than that in control endometrium. The decreased PDCD5 expression was correlated with the tumor differentiation degree. It is clear that PDCD5 protein expression was lower in middle and low differentiated endometrial carcinoma compared with control endometrium and high differentiated endometrial carcinoma. However, there were no significant differences of PDCD5 expression between the proliferative phase and the secretory phase of control endometrium, as well as between high differentiated endometrial carcinoma and controls. The results were verified in control glandular epithelial cells and KLE cells by immunocytochemistry. Therefore, PDCD5 may play a key role in the pathogenesis of endometrial cancer and may be a novel target for diagnosis and treatment of endometrial cancer.

Metformin targeting autophagy overcomes progesterone resistance in endometrial carcinoma

PURPOSE

Metformin is the most prescribed anti-diabetic medication worldwide because of its proven efficacy and limited side effects. In this study, the significant anticancer effect of metformin was investigated in both endometrial carcinoma and progesterone-resistant endometrial carcinoma cells.

METHODS

We tested the growth inhibition assay using MTT cell proliferation, cell cycle assay, apoptosis assessment with flow cytometry using propidium iodide and Annexin V, and autophagy protein expression with western blot analysis.

RESULTS

Metformin inhibited the growth of cancer cells with different concentrations in a dose- and time-dependent manner. Moreover, the inhibition properties observed as a function of increased concentrations of metformin were markedly augmented when the medication was administered in the progesterone-resistant Ishikawa cells, even with a dose as low as 10 mM. The early and late phases of apoptosis were enhanced in the metformin-treated tumour cells that were analyzed. For the Ishikawa cells, the expression of p-AMPK, LC-3, and beclin1 was upregulated after treatment, whereas the AMPK levels were not modulated. Furthermore, for the Ishikawa-PR cells, the protein levels were similarly upregulated. Finally, we observed that the three proteins showed much more variability in Ishikawa-PR cells than in Ishikawa cells.

CONCLUSION

The application of metformin to target autophagy in endometrial cancer cells provides a new potential treatment for progesterone-resistant endometrial carcinoma.

Endometrial hyperplasia-related inflammation: its role in the development and progression of endometrial hyperplasia

BACKGROUND

Endometrial hyperplasia (EH) is one of the most common gynecologic diseases in the world. Different statistical categories implicate an imbalance of estrogens and progestogens in the etiology of this disease. We propose that inflammation also plays a key role in the progression of endometrial hyperplasia.

OBJECTIVE

The aim of this study is to evaluate the role of inflammation in the transformation and progression of endometrial hyperplasia, using local inflammatory cytokines and nonspecific protease levels, CD 45(+) expression, and histological examination.

DESIGN

The study included 107 patients (ages 29-49 years) with different forms of endometrial hyperplasia. The enrolled patients were randomized into one of the four groups: normal endometrium (n = 18) as the control group, simple hyperplasia (n = 41), complex hyperplasia without atypia (n = 36), complex atypical hyperplasia or endometrioid adenocarcinoma (n = 12).

METHODS

The following were evaluated for patients with different forms of EH: steroid hormone levels in blood serum and uterine flushings, immunohistochemical estrogen and progesterone receptor expression patterns in the endometrial tissue, CD 45(+) (common leukocyte antigen) expression, the levels of the cytokines IL-1β, IL-6, and TNF-α, and nonspecific proteases and their inhibitors.

RESULTS

The level of estradiol in blood serum and especially in uterine flushings was elevated dramatically in simple EH as compared to that of controls, but there was no significant difference between estradiol levels among the different forms of EH. The estimation of CD 45(+), the levels of the cytokines IL-1β, IL-6, and TNF-α, and the activity of proteases (elastase-like and trypsin-like activities) and their inhibitors showed that levels of nonspecific inflammatory markers increase with EH progression.

CONCLUSIONS

We suggest that the initial responsibility for the development of simple endometrial hyperplasia belongs to systemic hyperestrogenemia and, in particular, local hyperestrogenia, but that the role of inflammatory processes increases in complex and atypical EH. Development of inflammatory changes in endometrial hyperplasia may be considered as a factor in the promotion and progression of pathology, as well as an attributed risk factor for malignancy in endometrial hyperplasia. In this study, we have established a role for CD 45(+) expression cells, non-specific proteases, and the inflammatory cytokines IL-1β, IL-6, and TNF-α in endometrial hyperplasia-related inflammation.

Effect of letrozole in carcinogen-plus-estrogen-induced endometrial hyperplasia in mice

PURPOSE

To evaluate the effects of letrozole (Ltz) in carcinogen+estrogen-induced endometrial hyperplasia.

METHODS

BALB/c female mice were divided into four groups of 12 animals each receiving an intrauterine dose of N-ethyl-N-nitrosourea (ENU) and weekly subcutaneous injections of estradiol hexaidrobenzoate (EHB), except for group I(control). The groups were divided in I (control), II (ENU+EHB), III (ENU+EHB+MPA) and IV (ENU+EHB+Ltz). Group III also received intramuscular injections of MPA (medroxy progesterone acetate) every four weeks, while group IV received oral doses of Ltz daily. At the end of 16 weeks, the animals were sacrificed, and blood samples were collected for the measurement of serum estradiol and progesterone levels. Uterine histological sections were made to evaluate the presence of endometrial proliferative lesions. Differences between groups were evaluated with student's t test, ANOVA and chi-square test.

RESULTS

Groups ENU+EHB, ENU+EHB+MPA and ENU+EHB+Ltz showed varying degrees of endometrial hyperplasia. The incidence of hyperplasia in groups ENU+EHB and ENU+EHB+Ltz was higher and more severe than in group ENU+EHB+MPA. Control group showed lower levels of serum estradiol than the other groups.

CONCLUSION

There was no evidence that letrozole could act as an antiestrogenic drug in the development of endometrial proliferative lesions.

Childhood body mass index and height and risk of histologic subtypes of endometrial cancer

Background:

Endometrial cancer risk factors include adult obesity and taller stature, but the influence of size earlier in life is incompletely understood. We examined whether childhood body mass index (BMI; kg m⁻²) and height were associated with histologic subtypes of endometrial cancer.

Methods:

From the Copenhagen School Health Records Register, 155 505 girls born 1930–1989 with measured weights and heights from 7 to 13 years were linked to health registers. BMI and height were transformed to age-specific z-scores. Hazard ratios (HRs) and 95% confidence intervals were estimated by Cox regressions.

Results:

A total of 1020 endometrial cancers were recorded. BMI was non-linearly associated with all endometrial cancers, oestrogen-dependent cancers and the subtype of endometrioid adenocarcinomas; associations were statistically significant and positive above a z-score=0 and non-significant below zero. Compared with a 7-year-old girl with a BMI z-score=0, an equally tall girl who was 3.6 kg heavier (BMI z-score=1.5) had a hazard ratio=1.53 (95% confidence interval: 1.29–1.82) for endometrioid adenocarcinoma. BMI was not associated with non-oestrogen-dependent cancers, except at the oldest childhood ages. Height at all ages was statistically significant and positively associated with all endometrial cancers, except non-oestrogen-dependent cancers. At 7 years, per ~5.2 cm (1 z-score), the risk of endometrioid adenocarcinoma was 1.18 (95% confidence interval: 1.09–1.28). Among non-users of unopposed oestrogens, associations between BMI and endometrioid adenocarcinoma strengthened, but no effects on height associations were observed.

Conclusions:

Endometrial carcinogenesis is linked to early-life body size, suggesting that childhood BMI and height may be useful indicators for the risk of later development of endometrial cancer and might aid in the early prevention of obesity-related endometrial cancers.

Prognostic significance of a component of the Hippo pathway, TAZ, in human uterine endometrioid adenocarcinoma

Transcriptional coactivator with PDZ-binding motif (TAZ) is a crucial component of the Hippo tumor suppressor pathway, interacting with transcriptional factors to regulate cell proliferation, apoptosis and tumorigenesis. TAZ and its paralog, Yes-associated protein (YAP), are activated at high frequencies during the progression towards malignancy in various tumors. Recently, YAP has been identified to modulate oncogenic features in endometrial adenocarcinoma, and it has also been reported that the nuclear expression of YAP is correlated with the poorly-differentiated form of endometrioid adenocarcinoma. In contrast to YAP, no studies have investigated TAZ expression in endometrioid adenocarcinoma. In the present study, TAZ expression was immunohistochemically examined in 55 clinical samples of endometrioid adenocarcinoma, and the clinical implications were evaluated. The results demonstrated that TAZ was located primarily in the cell nuclei, and that high TAZ expression was significantly correlated with high tumor-factor (P=0.024), stage (P=0.041) and histological grade (P=0.001), lymph node metastasis (P=0.046), recurrence (P=0.002) and a poor prognosis (P=0.007). Furthermore, univariate analysis identified that high TAZ expression was a poor prognostic factor for overall and disease-free survival. To the best of our knowledge, the present case is the first to report the clinical implications of TAZ in endometrioid adenocarcinoma of the uterus. TAZ may become a marker of a poor prognosis in endometrioid adenocarcinoma.

Loss of Mismatch Repair Protein Expression in Unselected Endometrial Adenocarcinoma Precursor Lesions

OBJECTIVE

The benefit of evaluating the precursor of endometrial carcinoma, endometrial hyperplasia (intraepithelial neoplasia [EIN]), for loss of mismatch repair (MMR) protein expression and Lynch syndrome has yet to be determined. The present study aims to establish the incidence and type of loss of MMR protein expression in unselected premalignant lesions of endometrial adenocarcinoma, as well as the agreement of immunohistochemical staining in pretreatment endometrial biopsy (EMB) specimens with subsequent uterine resections.

METHODS

A retrospective review identified 112 endometrial biopsies meeting criteria for endometrial EIN. Slides made from tissue microarray blocks were evaluated using antibodies against MLH1, PMS2, MSH2, and MSH6. Cases with a deficit in MLH1 were evaluated for gene promoter hypermethylation by polymerase chain reaction analysis. Fifty-four subsequent hysterectomy specimens were retrieved and assessed for MMR protein expression.

RESULTS

Of the 112 endometrial biopsies with EIN, 4.5% (5/112) exhibited loss of MMR protein expression. The majority (4/5) demonstrated a deficit of MLH1, of which all exhibited inactivation via promoter hypermethylation. A single case displayed an absence of MSH6. Age was not significantly associated with MMR deficiency. There was no significant association between MMR status in the EMB and a subsequent diagnosis of cancer. Immunohistochemical staining in all successive hysterectomy cases was concordant with the pattern observed in the EMB specimen.

CONCLUSIONS

Sporadic hypermethylation of MLH1 seems to be the primary mechanism underlying defective MMR protein expression in EIN. Among our cohort, only 1 patient (<1%) had a mutation suggestive of a hereditary inheritance. Hence, the utility of evaluating EIN for MMR protein expression as a screen for Lynch syndrome is limited, regardless of age.

Endometrial Carcinoma: Role of Current and Emerging Biomarkers in Resolving Persistent Clinical Dilemmas

OBJECTIVES

Type II and other high-grade endometrial carcinomas may challenge conventional treatment due to recurrence and metastatic spread and therefore are a persistent clinical dilemma. Effective targeted therapy for these is a goal for clinicians and researchers alike.

METHODS

An extensive review of the literature has been performed for obtaining an in-depth understanding of the clinicopathological characteristics, etiologic factors, and molecular profile of these subsets of endometrial carcinoma. Progress made with current and emerging biomarkers for prognosis assessment and therapeutic targeting has been summarized.

RESULTS

There has been a significant increase in research on potential biomarkers of endometrial cancer, and beneficial targeted therapies have been identified.

CONCLUSIONS

Clinical trials are leading the charge for substantial gains toward personalized treatment of aggressive endometrial carcinoma subtypes.

Changes in c-erbB-2 Immunoexpression in Feline Endometrial Adenocarcinomas

Human epidermal growth factor receptor type 2 (c-erbB-2), an oncoprotein with potential prognostic marker and therapeutic use, is overexpressed in several human and animal tumours. But information regarding this molecule in feline tumours is scarce. This study aimed to assess the changes in the immunohistochemical expression of c-erbB-2 in feline endometrial adenocarcinomas (FEA) compared to normal endometrium. An immunohistochemistry assay using a specific antibody against c-erbB-2 was performed in FEA samples (n = 34) and in normal endometrium in the follicular (FS; n = 12) and luteal (LS; n = 11) stages. In FEA, the c-erbB-2 immunoexpression was assessed in neoplastic epithelial cells whilst in normal endometria it was individually evaluated in the surface and the superficial and deep glandular epithelia (SE, SGE and DGE, respectively). In FS and in LS, all the epithelia were positive for c-erbB-2; positivity was higher in the SE and the SGE than in DGE. Twenty of the 34 FEA samples (58.8%) were positive for c-erbB-2 immunolabelling. Nevertheless, its expression was higher in all the epithelia in the FS compared to FEA (p ≤ 0.0001) or the LS (p = 0.016). The results presented herein suggest that c-erbB-2 molecule is differently expressed in the feline endometrium through the oestrous cycle and though it may also be involved in feline endometrial carcinogenesis, a question remains unanswered on the importance of additional pathways of epithelial proliferation in the neoplastic changes in feline endometrium.

Uterine Carcinomas in Tetrabromobisphenol A-exposed Wistar Han Rats Harbor Increased Tp53 Mutations and Mimic High-grade Type I Endometrial Carcinomas in Women

Endometrial carcinoma is the most common gynecologic malignancy is the United States and accounts for 6% of all cancers in women. The disease is classified as type I or type II based on clinicopathologic and molecular features. It is a multifactorial disease with a number of risk factors, including environmental exposures. How environmental exposures, such as flame retardants, may affect the incidence of endometrial cancer is a topic of current and ongoing interest. Tetrabromobisphenol A (TBBPA) is a widely used brominated flame retardant found in a variety of household products. A recent 2-year National Toxicology Program carcinogenicity study found that exposure to TBBPA was associated with a marked increase in the development of uterine tumors, specifically uterine carcinomas, in Wistar Han rats. Molecularly, TBBPA-induced uterine carcinomas in Wistar Han rats were characterized by a marked increase in tumor protein 53 mutation compared to spontaneous uterine carcinomas, as well as overexpression of human epidermal growth factor receptor 2. Similar to spontaneous carcinomas, tumors in TBBPA-exposed rats were estrogen receptor-alpha positive and progesterone receptor negative by immunohistochemistry. The morphologic and molecular features of uterine carcinomas in TBBPA-exposed rats resemble those of high-grade type I tumors in women, and these data suggest that exposure to TBBPA may pose an increased cancer risk.

Regulation of Androgen Receptor Expression Alters AMPK Phosphorylation in the Endometrium: In Vivo and In Vitro Studies in Women with Polycystic Ovary Syndrome

The failure of reproductive success in polycystic ovary syndrome (PCOS) patients could be in part due to endometrial dysfunction. However, no studies have investigated any causality between androgen, androgen receptor (AR) expression, and adenosine monophosphate activated protein kinase (AMPK) activation in the endometrium under physiological and pathological conditions. In the present study, we show that 1) endometrial AR expression levels fluctuate in non-PCOS and PCOS patients during the menstrual cycle; 2) the menstrual phase-dependent alteration of p-AMPKα expression occurs in non-PCOS patients but not in PCOS patients; 3) AR expression is higher in PCOS patients than non-PCOS patients during hyperplasia while AMPKα activation (indicated by the ratio of p-AMPKα to AMPKα); and 4) co-localization of AR and Ki-67 in epithelial cell nuclei is observed in endometrial hyperplasia. Importantly, using in vitro human tissue culture and an in vivo 5α-dihydrotestosterone-treated rat model, we show that the action of androgen on AMPKα activation is likely mediated through nuclear AR, especially in epithelial cells. Collectively, we present evidence that AR expression and AMPKα activation depend on menstrual cycle phase and the presence of PCOS, and the data suggest that AR-mediated regulation of AMPKα activation might play a role in the development of endometrial hyperplasia.

Levonorgestrel-releasing intrauterine system vs oral progestins for non-atypical endometrial hyperplasia: a systematic review and metaanalysis of randomized trials

We sought to evaluate the therapeutic efficacy of levonorgestrel-releasing intrauterine system (LNG-IUS) with oral progestins for treatment of non-atypical endometrial hyperplasia (EH). Searches were conducted on PubMed, SCOPUS, and CENTRAL databases to August 2014, and reference lists of relevant articles were screened. The search was limited to articles conducted on human beings and females. The PRISMA Statement was followed. Seven randomized controlled trials (n = 766 women) were included. Main outcome measures were the therapeutic effect rate (histological response) after 3, 6, 12, and 24 months of treatment; rate of irregular vaginal bleeding; and the hysterectomy rate per woman randomized. The Cochrane Collaboration risk of bias tool was used for quality assessment. Metaanalysis was performed with fixed effects model. LNG-IUS achieved a highly significant therapeutic response rate compared with oral progestins after 3 months of treatment (odds ratio [OR], 2.30; 95% confidence interval [CI], 1.39-3.82; P = .001, 5 trials, I(2) = 0%, n = 376), after 6 months of treatment (OR, 3.16; 95% CI, 1.84-5.45; P < .00001, 4 trials, I(2) = 0%, n = 397), after 12 months of treatment (OR, 5.73; 95% CI, 2.67-12.33; P < .00001, 2 trials, I(2) = 0%, n = 224), and after 24 months of treatment (OR, 7.46; 95% CI, 2.55-21.78; P = .0002, 1 trial, n = 104). Subgroup analysis showed evidence of highly significant therapeutic response following LNG-IUS compared with oral progestins for non-atypical simple as well as complex EH (OR, 2.51; 95% CI, 1.14-5.53; P = .02, 6 trials, I(2) = 0%, n = 290; and OR, 3.31; 95% CI, 1.62-6.74; P = .001, 4 trials, I(2) = 0%, n = 216, respectively). Compared with oral progestins, LNG-IUS achieved significantly fewer hysterectomies (OR, 0.26; 95% CI, 0.15-0.45; P < .00001, 3 trials, n = 362, I² = 42%). No difference was observed in the rate of irregular vaginal bleeding between both groups (OR, 1.12; 95% CI, 0.54-2.32; P = .76, 2 trials, n = 207, I² = 77%). Funnel plot analysis was not performed because of the relatively small number of included studies. For treatment of non-atypical EH, LNG-IUS achieves higher therapeutic effect rates and lower hysterectomy rates than oral progestins and should be offered as an alternative to oral progestins in these cases.

An immunohistochemical study on the expression of sex steroid receptors, Ki-67 and cytokeratins 7 and 20 in feline endometrial adenocarcinomas

BACKGROUND

Endometrial adenocarcinomas are a rare type of tumour in cats. Though different morphologies have been reported, the most frequent histological type of feline endometrial adenocarcinoma (FEA) is the papillary serous. Characterization of molecular markers expression in FEA may contribute to clarify the pathogenesis of these tumours and to assess the differences between normal endometrium and FEA regarding the expression pattern of several proteins. Therefore, this study aimed to evaluate the immunohistochemical profile of a wide panel of antibodies (specific for ER-α, PR, Ki-67, CK7 and CK20) in twenty-four cases of FEA. Comparisons were made between FEA and feline normal cyclic endometrium in follicular (n = 13) and luteal (n = 10) stages. Except for Ki-67, all other molecular markers were assessed independently for the intensity of immunolabeling and for the percentage of cells expressing the protein.

RESULTS

This study showed that in FEA a loss of expression occurs for ER-α (P ≤ 0.0001) and less markedly also for PR. The lost in sex steroid receptors concerns a decrease in both the proportion of labelled cells and the intensity of immunolabelling (P = 0.002 and P = 0.024, respectively). Proliferative activity, estimated via Ki-67 immunoreaction, significantly increased in FEA as compared to normal endometrium (P ≤ 0.0001). Feline endometrial adenocarcinomas maintained the CK7+/CK20+ status of normal endometrium. However, FEA showed decreased CK7 intensity of labelling compared to normal endometria (P ≤ 0.0001) and loss of CK20 expression, both in intensity (P ≤ 0.0001) and in percentage of positive cells (P = 0.01), compared to normal tissues.

CONCLUSIONS

Data gathered in this study suggest that proliferation in FEA accompanies ER-α down-regulation, possibly following activation of pathways mediated by local growth factors. Moreover, FEA retains combined expression of CK7 and CK20, as evidenced in normal endometrial epithelia, although a decrease in CK7 expression was observed.

Loss of Cdh1 and Trp53 in the uterus induces chronic inflammation with modification of tumor microenvironment

Type II endometrial carcinomas (ECs) are estrogen independent, poorly differentiated tumors that behave in an aggressive manner. As TP53 mutation and CDH1 inactivation occur in 80% of human endometrial type II carcinomas, we hypothesized that mouse uteri lacking both Trp53 and Cdh1 would exhibit a phenotype indicative of neoplastic transformation. Mice with conditional ablation of Cdh1 and Trp53 (Cdh1(d/d)Trp53(d/d)) clearly demonstrate architectural features characteristic of type II ECs, including focal areas of papillary differentiation, protruding cytoplasm into the lumen (hobnailing) and severe nuclear atypia at 6 months of age. Further, Cdh1(d/d)Trp53(d/d) tumors in 12-month-old mice were highly aggressive, and metastasized to nearby and distant organs within the peritoneal cavity, such as abdominal lymph nodes, mesentery and peri-intestinal adipose tissues, demonstrating that tumorigenesis in this model proceeds through the universally recognized morphological intermediates associated with type II endometrial neoplasia. We also observed abundant cell proliferation and complex angiogenesis in the uteri of Cdh1(d/d)Trp53(d/d) mice. Our microarray analysis found that most of the genes differentially regulated in the uteri of Cdh1(d/d)Trp53(d/d) mice were involved in inflammatory responses. CD163 and Arg1, markers for tumor-associated macrophages, were also detected and increased in the uteri of Cdh1(d/d)Trp53(d/d) mice, suggesting that an inflammatory tumor microenvironment with immune cell recruitment is augmenting tumor development in Cdh1(d/d)Trp53(d/d) uteri. Further, inflammatory mediators secreted from CDH1-negative, TP53 mutant endometrial cancer cells induced normal macrophages to express inflammatory-related genes through activation of nuclear factor-κB signaling. These results indicate that absence of CDH1 and TP53 in endometrial cells initiates chronic inflammation, promotes tumor microenvironment development following the recruitment of macrophages and promotes aggressive ECs.

Identification of subgroup-specific miRNA patterns by epigenetic profiling of sporadic and Lynch syndrome-associated colorectal and endometrial carcinoma

Background

Altered expression of microRNAs (miRNAs) commonly accompanies colorectal (CRC) and endometrial carcinoma (EC) development, but the underlying mechanisms and clinicopathological correlations remain to be clarified. We focused on epigenetic mechanisms and aimed to explore if DNA methylation patterns in tumors depend on DNA mismatch repair (MMR) status, sporadic vs. Lynch-associated disease, and geographic origin (Finland vs. Australia). Treatment of cancer cell lines with demethylating agents revealed 109 significantly upregulated miRNAs. Seven met our stringent criteria for possible methylation-sensitive miRNAs and were used to screen patient specimens (205 CRCs and 36 ECs) by methylation-specific multiplex ligation-dependent probe amplification.

Results

Three miRNAs (129-2, 345, and 132) with low methylation levels in normal tissue and frequent hypermethylation in tumors were of particular interest. Hypermethylation of miR-345 and miR-132 associated with MMR deficiency in CRC regardless of geographic origin, and hypermethylation of miR-132 distinguished sporadic MMR-deficient CRC from Lynch-CRC. Finally, hypermethylation of miRNAs stratified 49 endometrial hyperplasias into low-methylator (simple hyperplasia) and high-methylator groups (complex hyperplasia with or without atypia) and suggested that miR-129-2 methylation in particular could serve as a marker of progression in early endometrial tumorigenesis.

Conclusions

Our study identifies miR-345 and miR-132 as novel differentially methylated miRNAs in CRC, thereby facilitating sub-classification of CRC and links miR-129-2 methylation to early endometrial tumorigenesis.

Electronic supplementary material

The online version of this article (doi:10.1186/s13148-015-0059-3) contains supplementary material, which is available to authorized users.

Phytoestrogen genistein inhibits EGFR/PI3K/NF-kB activation and induces apoptosis in human endometrial hyperplasial cells

Endometrial hyperplasia is an estrogen-dependent disease and is the most frequent precursor of endometrial cancer, diagnosed in pre- and peri-menopausal women.

Inhibitory effect of 2-(piperidinoethoxyphenyl)-3-(4-hydroxyphenyl)-2H-benzo(b)pyran (K-1) on human primary endometrial hyperplasial cells mediated via combined suppression of Wnt/β-catenin signaling and PI3K/Akt survival pathway

Endometrial hyperplasia is a precursor to the most common gynecologic cancer diagnosed in women. Apart from estrogenic induction, aberrant activation of the Wnt/β-catenin signal is well known to correlate with endometrial hyperplasia and its carcinoma. The benzopyran compound 2-(piperidinoethoxyphenyl)-3-(4-hydroxyphenyl)-2H-benzo (b) pyran(K-1), a potent antiestrogenic agent, has been shown to have apoptosis-inducing activity in rat uterine hyperplasia. The current study was undertaken to explore the effect of the benzopyran compound K-1 on growth and Wnt signaling in human endometrial hyperplasial cells. Primary culture of atypical endometrial hyperplasial cells was characterized by the epithelial cell marker cytokeratin-7. Results revealed that compound K-1 reduced the viability of primary endometrial hyperplasial cells and expression of ERα, PR, PCNA, Wnt7a, FZD6, pGsk3β and β-catenin without affecting the growth of the primary culture of normal endometrial cells. The β-catenin target genes CyclinD1 and c-myc were also found to be reduced, whereas the expression of axin2 and Wnt/β-catenin signaling inhibitor Dkk-1 was found to be upregulated, which caused the reduced interaction of Wnt7a and FZD6. Nuclear accumulation of β-catenin was found to be decreased by compound K-1. K-1 also suppressed the pPI3K/pAkt survival pathway and induced the cleavage of caspases and PARP, thus subsequently causing the apoptosis of endometrial hyperplasial cells. In conclusion, compound K-1 suppressed the growth of human primary endometrial hyperplasial cells through discontinued Wnt/β-catenin signaling and induced apoptosis via inhibiting the PI3K/Akt survival pathway.

Promising clinical practices of metformin in women with PCOS and early-stage endometrial cancer

Young women with polycystic ovary syndrome (PCOS) have a high risk of developing endometrial cancer (EC). There is an urgent need for non-surgical prevention and treatment strategies for these patients who fail to respond to progesterone treatment and wish to preserve their fertility. Recently, we have reported that the combined treatment with metformin and progesterone-based oral contraceptives has successfully reversed the early-stage EC into normal endometria in addition to improvement of insulin resistance in women with PCOS. More importantly, one of these treated women has successfully delivered a healthy newborn baby. However, before such treatment can be recommended to the clinical practice, the molecular basis of metformin in the endometrium under physiological and pathological conditions must be elucidated.

Direct effects of metformin in the endometrium: a hypothetical mechanism for the treatment of women with PCOS and endometrial carcinoma

Although a number of in vitro studies have demonstrated the antiproliferative, anti-invasive, and antimetastatic effects of metformin in multiple cancer cell types, its cellular and molecular mechanisms of anti-cancer action in the endometrium of women with polycystic ovary syndrome (PCOS) have not yet been fully elucidated. Organic cation transporters (OCTs) and multidrug and toxin extrusion proteins (MATEs) are known to be involved in metformin uptake and excretion in cells. In this article, we discuss the novel therapeutic possibilities for early-stage endometrial carcinoma (EC) in women with PCOS focusing on metformin, which might have a direct effect in the endometrium through the OCTs and MATEs. We then review the molecular mechanism(s) of the action of metformin in the endometrium and highlight possible mechanistic insights into the inhibition of cell proliferation and tumor growth and, ultimately, the reversal of early-stage EC into normal endometria in women with PCOS.

Clinicopathological analysis of intraductal proliferative lesions of prostate: intraductal carcinoma of prostate, high-grade prostatic intraepithelial neoplasia, and atypical cribriform lesion

Intraductal carcinoma of the prostate (IDC-P) and high-grade prostatic intraepithelial neoplasia (HGPIN) are two distinct intraductal lesions; the former is usually associated with invasive carcinoma and has an aggressive course while the latter is considered a precancerous lesion. In addition, there are morphologically lesions not well characterized that fall between IDC-P and HGPIN, consequently termed "atypical cribriform lesions (ACLs)." Using whole mount radical prostatectomy specimens, we evaluated the relationship between these intraductal proliferative lesions and clinicopathological parameters. In this study, ACLs were characterized as a loose cribriform intraductal proliferation with greater architectural complexity when compared to HGPIN, but lacking significant nuclear pleomorphism and/or comedonecrosis. Of 901 radical prostatectomies (2006-2012), IDC-P, ACL, and HGPIN were recorded in 155, 22, 436 cases, respectively. Patients with IDC-P showed more aggressive pathologic features when compared to HGPIN. Invasive cancers in patients with ACL had higher Gleason score (P=.00016), larger tumor volume (P=.025), and more advanced pT stage (P=.023) than those with HGPIN. Cases with ACL showed a higher risk of biochemical recurrence than those with HGPIN and a lower risk than those with IDC-P based on log-rank tests (P=.0045 and P=.0069, respectively). In multivariate analysis, the presence of HGPIN was identified as an independent predictor for infrequent biochemical recurrence (P=.0058). We confirmed IDC-P as a marker of adverse pathologic features and clinical aggressiveness. Our results suggest that ACL should be distinguished from HGPIN and these lesions mandate active clinical surveillance.

Incidence of pyometra in Swedish insured cats

Pyometra is a clinically relevant problem in intact female cats and dogs. The etiology is similar in both animal species, with the disease caused by bacterial infection of a progesterone-sensitized uterus. Here, we studied pyometra in cats with the aim to describe the incidence and probability of developing pyometra based on age and breed. The data used were reimbursed claims for veterinary care insurance or life insurance claims or both in cats insured in a Swedish insurance database from 1999 to 2006. The mean incidence rate (IR) for pyometra was about 17 cats per 10,000 cat years at risk (CYAR). Cats with pyometra were diagnosed at a median age of 4 years and a significant breed effect was observed. The breed with the highest IR (433 cats per 10,000 CYAR) was the Sphynx, and other breeds with IR over 60 cats per 10,000 CYAR were Siberian cat, Ocicat, Korat, Siamese, Ragdoll, Maine coon, and Bengal. Pyometra was more commonly diagnosed with increasing age, with a marked increase in cats older than 7 years. The mean case fatality rate in all cats was 5.7%, which is slightly higher than corresponding reports in dogs of 3% to 4%. Geographical location (urban or rural) did not affect the risk of developing the disease. The present study provides information of incidence and probability of developing pyometra based on age, breed, and urban or rural geographical location. These data may be useful for designing cat breeding programs in high-risk breeds and for future studies of the genetic background of the disease.

Progesterone receptor isoforms A and B: new insights into the mechanism of progesterone resistance for the treatment of endometrial carcinoma

Progesterone therapy is an effective treatment for atypical endometrial hyperplasia and early endometrial carcinoma (EC). However, progesterone resistance is the main obstacle to the success of conservative treatment in women with type I EC and remains a major clinical challenge. Studies indicate that progesterone and progesterone receptors (PRs) play a significant role in both normal and neoplastic endometria. Most EC arises in the epithelial cells of the endometrial glands, and a large body of in vitro evidence suggests that the absence or reduced expression of PR isoform B might result in the failure of progesterone treatment and lead to aberrant PRB-mediated signalling in EC cells. A recently developed in vivo knockout mouse model suggests that enhanced DNA methylation decreases the level of stromal PR isoform A and that this is also a main contributor to progesterone resistance in EC cells. The endometrial stroma within the EC might create a microenvironment that determines how epithelial-derived cancer cells respond to progesterone. This novel study opened a new avenue for research seeking to clarify the mechanisms that regulate the specific PR isoforms that are associated with the stromal cell responses to progesterone and has led to new understanding of both endometrial cell-specific and mechanical contributions of the stroma to EC development.

A multimarker qPCR platform for the characterisation of endometrial cancer

The molecular background of endometrial cancer (EC) has not been fully elucidated. In the present study, we developed a quantitative PCR (qPCR) platform to examine the gene dosages of the potential molecular markers MGB1, TOP2A, ERBB1-4, MYC, CCND1, ESR1 and PI3K. The platform was applied in samples collected from 157 EC patients (stage I-IV) to verify its clinical utility and to examine the diagnostic and prognostic significance of the analysed biomarkers. The gene dosage pattern of the ERBB family and its downstream effectors PI3K and MYC showed particularly strong correlations with clinicopathological data. The ERBB PI3K/Akt pathway was upregulated in 31 (20%) of 156 cases. Activation of the ERBB PI3K/Akt pathway was positively correlated with a higher stage (p=0.001), higher grade (p=0.001), histological type II disease (p=0.0003) and metastases (p=0.02). The implemented hierarchical clustering revealed that cluster 2 was characterised by high copy numbers of the studied genes. Cluster 2 was associated with shorter overall survival (p=0.05). The platform was found to be a fast and simple method for direct analysis of the genes involved in uterine carcinogenesis, making it feasible for EC biology characterisation.