Coexpression of estrogen receptors alpha and beta in serous ovarian cancer

Abstract

Background. In recent years, interest in hormonal treatment of ovarian cancer has revived and a number of fundamental questions associated with the expression in these tumors of different types of estrogen receptors (ER) - ERa and ERß - have arisen. Objective: to answer the questions, what is the frequency and level of expression of ERa and ERß in the tissue of ovarian cancer and is it possible co-expression of ERa and ERß in different and/or in the same tumor cells. Materials and methods. A comparative quantitative assessment of the frequency and level of expression of ERa and ERß in the tissue of ovarian cancer (a total of 20 samples) was carried out using the immunofluorescence method and flow cytometry, including the method of double fluorescent staining developed by the authors. Results. ERß expression was found in all ovarian cancer samples, but there are both ERa+ and ERa^- tumors. In most ERa+ tumors (69 % of cases), a low (<40 %) level of ERa expression was observed. Moreover, in the study of tumors with a high level of expression of both ERa and ERß, co-expression of the markers in the same cells of the examined tumors was revealed. Conclusions. In the ovarian cancer tissue, different types of ER - ERa and ERß - can be expressed in different tumor cells, as well as co-expressed both in different and in the same tumor cells.