title: Disturbed estrogen and progesterone action in ovarian endometriosis.
abstract: Endometriosis is a very common disease in pre-menopausal women, where defective metabolism of steroid hormones plays an important role in its development and promotion. In the present study, we have examined the expression of 11 estrogen and progesterone metabolizing enzymes and their corresponding receptors in samples of ovarian endometriomas and control endometrium. Expression analysis revealed significant up-regulation of enzymes involved in estradiol formation (aromatase, sulfatase and all reductive 17beta-hydroxysteroid dehydrogenases) and in progesterone inactivation (AKR1C1 and AKR1C3). Among the estrogen and progesterone receptors, ERalpha was down-regulated, ERbeta was up-regulated, and there was no significant difference in expression of progesterone receptors A and B (PRAB). Our data indicate that several enzymes of estrogen and progesterone metabolism are aberrantly expressed in endometriosis, which can lead to increased local levels of mitogenic estradiol and decreased levels of protective progesterone. Changes in estrogen receptor expression suggest that estradiol may also act via non-estrogen receptor-mediated pathways, while expression of progesterone receptors still needs further investigation.
authors.affiliation: Institute of Biochemistry, Faculty of Medicine, University of Ljubljana, Vrazov trg 2, 1000 Ljubljana, Slovenia. Tina.Smuc@mf.uni-lj.si
authors.forename: Tina
authors.initials: T
authors.lastname: Smuc
authors.forename: Neli
authors.initials: N
authors.lastname: Hevir
authors.forename: Martina
authors.initials: M
authors.lastname: Ribic-Pucelj
authors.forename: Bettina
authors.initials: B
authors.lastname: Husen
authors.forename: Hubert
authors.initials: H
authors.lastname: Thole
authors.forename: Tea Lanisnik
authors.initials: TL
authors.lastname: Rizner