Molecular Profile (Estrogen Receptor, Progesterone Receptor, Bcl-2 and Ki-67) of the Ectopic Endometrium in Patients with Endometriosis

Endometriosis is characterized by alterations of the action and control mechanisms that lead to the development of ectopic endometrial tissue. This study aimed to analyze the molecular profile of ectopic endometrium by evaluating the expression of several biomarkers [estrogen receptor (ER), progesterone receptor (PR), anti-apoptotic protein Bcl-2, and Ki-67 antigen] in relation to the stage of the disease and symptoms. A prospective study over a period of one year, consisting of 14 patients with endometriosis, was performed. All patients received laparoscopic surgical treatment for excision of the lesions and staging of the disease. The expression of the aforementioned biomarkers was assessed in the ectopic endometrial tissue from the excised lesions using immunohistochemistry to determine their expression in the glandular epithelium and stroma. The mean expression of biomarkers in the epithelial and stromal levels did not differ significantly based on disease stage. Epithelial ER expression was significantly positively correlated with stromal ER, epithelial PR, and stromal PR. Stromal ER was significantly positively correlated with epithelial PR and stromal Ki-67. Epithelial Bcl-2 was significantly positively correlated with stromal Bcl-2. Epithelial Ki-67 was significantly positively correlated with stromal Ki-67. Finally, epithelial Bcl-2 expression was significantly positively correlated with the intensity of dyspareunia. The correlation between epithelial Bcl-2 expression and the intensity of dyspareunia highlights a potential molecular link to the severity of symptoms in endometriosis. These results suggest that further exploration of these biomarkers could lead to improved understanding of their clinical implications and more personalized therapies for patients with endometriosis.