Endometriomas are extremely heterogenous for steroidogenic activity, functional FSH receptor expression and FSH-responsive aromatase transcript variants

Abstract

Study question Do all ovarian endometriomas uniformly express functional FSH receptors and the full cascade of steroidogenic enzymes?

Summary answer No. They are extremely heterogenous for the expression of FSH receptors, in response to FSH and steroidogenic enzymes and estrogen production.

What is known already Endometriotic stromal cells express aromatase and other steroidogenic enzymes required for de novo estradiol synthesis. Previous studies demonstrated the expression of FSH receptors in ovarian endometriomas and other types of endometriosis lesions mainly by immunohistochemistry and qRT-PCR methods. These methodologies, however, cannot prove the functionality of these receptors. We therefore aimed to investigate 1) if all endometriomas uniformly express FSH receptors and full cascade of steroidogenic enzymes and, 2) if FSH treatment uniformly up-regulates the expression of aromatase transcript variants and stimulates estrogen production in the endometriomas expressing FSH receptors.