The features of the expression of sex steroids hormone receptors, pro-inflammatory markers and cyclin-dependent kinase inhibitor protein p16ink4a in endometrium at external genital endometriosis

Abstract

Background. A local inflammatory reaction in the endometrium caused by viral infection and associated with external genital endometriosis (EGE) can affect the implantation properties of endometrium and be one of the causes of infertility. The aim of the study was to investigate the expression of estrogen and progesterone receptors, pro-inflammatory markers and inhibitor of cyclin-dependent kinases p16ink4a in the endometrium of women with infertility associated with EGE. Materials and methods. The object of the study was the material taken from 133 patients aged 19-35 years. Inclusion criteria were the presence of external genital endometriosis confirmed by laparoscopy and the absence of hormone treatment for 6 months prior to this study. Endometrial biopsies were obtained on 19-24 day of the menstrual cycle. Histological and immunohistochemical studies of endometrial biopsies were performed using standard methods. The expression of estrogen (ER) and progesterone receptors (PgR), inflammatory markers (CD8+, CD20+, CD4+, CD138+) and inhibitor of cyclin-dependent kinase p16ink4a were examined by immunohistochemistry. The evaluation of the expression of studied markers was performed in the epithelium of the glands and endometrial stromal component separately, using semiquantitative method H-Score, as well as qualitative and quantitative methods in image analysis system “Morphology 5.0” (VideoTest, Russia). Statistical analysis was performed using statistical software (STATGRAPHICS v.6.0). Results. A significant decrease in the expression of ER and PgR in endometrial stromal component was noted on the background of the high incidence of chronic endometritis in patients with EGE. All patients of the main group had a positive expression of p16ink4a. Conclusions. The obtained results indicate a high incidence of disorders of eutopic endometrial secretory transformation in patients with infertility associated with external genital endometriosis. The high incidence of the virus associated with chronic endometritis and sensitivity violation of endometrial tissue to sex steroid hormones, such as progesterone, may be a major determinant of infertility of patients in this group.