Molecular profile of eutopic and ectopic endometrium in endometriosis

C.A. Coroleucă, E. Brătilă, C.B. Coroleucă, M. Mitran, D. Comandașu

Rezumat: Endometriosis represents a chronic inflammatory disease defined by the appearance of endometrial tissue outside the uterine cavity, affecting mostly reproductive-aged women. Although some patients may be asymptomatic, the clinical features of endometriosis are frequently dominated by pelvic pain associated with infertility. Nonspecific symptomatology and the lack of biological screening markers with increased sensitivity and specificity lead to a slow diagnostic process. The hormonal profile of the eutopic and ectopic endometrium, molecular abnormalities and enzymatic mechanisms play a key role in the etiopathogenesis of endometriosis. Endometriotic implants are characterized by elevated levels of aromatase and 17β-HSD1 associated with low levels of 17β-HSD2 in response to low progesterone receptors, causing an increased level of estradiol. It is characteristic a status of progesterone resistance, described by the inability of endometrial tissue to respond adequately to progesterone, the activation failure of progesterone receptors and the use of available progesterone. Endometriosis is defined by abnormal cell proliferation of ectopic endometrial tissue associated with apoptosis mechanisms disorders. The level of apoptotic cells is reduced in the epithelium and stroma of the eutopic endometrium and does not increase at the end of the secretory phase, compared to the normal endometrium. Peritoneal endometriosis lesions associate elevated Bcl-2 levels, while ovarian endometriosis shows discordant results. The correlation between Ki-67 proliferation antigen level and the disease’s stage of evolution and aggressiveness was confirmed by numerous studies. The analysis of stem cells in the eutopic endometrium of patients with endometriosis showed morphological changes, altered expression of immunomodulatory molecules and an increased potential for invasion and proliferation. We believe that the characterization of the biochemical profile of the eutopic and ectopic endometrium is a current topic of interest in the understanding of endometriosis, its etiopathogeny and therapeutic approach. The main molecular features of ectopic endometrium present in endometriosis lesions are characterized by hyperestrogenemia, progesterone resistance, a reduced apoptosis capacity, an increased proliferation index, and the presence of abnormal multipotent stem cells.
Cuvinte cheie: endometriosis, molecular profile, eutopic endometrium, ectopic endometrium, Bcl-2, Ki-67, stem cells.