The presence of a membrane-bound progesterone receptor sensitizes the estradiol-induced effect on the proliferation of human breast cancer cells

• DOI: 10.1097/gme.0b013e31820e5ac5
• Publication Date: 2011-04-29T08:45:19Z
• Authors: Hans Neubauer; Yang Yang; Harald Seeger; Tanja Fehm; Michael A. Cahill; Xiaowen Tong; Xiangyan Ruan; Alfred O. Mueck
• Keywords: Progesterone receptor; Progestogen; MCF-7; Medroxyprogesterone

In Brief Objective: Breast cancer risk is still an important topic regarding hormone therapy as well oral contraception. Evidence that progestogens may play a crucial role accumulating. Progesterone receptor membrane component 1 (PGRMC1) expressed in breast be tumorigenesis and thus increase risk. The aim of this project was to investigate the influence different estradiol (E2) concentrations addition two on MCF-7 cells overexpressing PGRMC1. Methods: were stably transfected with PGRMC1 expression plasmid (MCF-7/PGRMC1-3HA [WT-12]). To test effects E2 cell proliferation, WT-12 stimulated (10−10 10−12 M) alone combination progesterone medroxyprogesterone acetate (each 10−6 M). Results: elicited concentration-dependent proliferative effect both lines, which much more pronounced (50% vs 200%). This could completely abrogated by antagonist fulvestrant. Addition had no E2-induced effect, whereas medroxy-progesterone enhanced at low concentration, was, again, cells. figures between 20% 40% 60% 250% Conclusions: Overexpression sensitizes response line estradiol. depend specific progestogen used for or overexpression trigger proliferation toward certain progestogens.