Progesterone and synthetic progestin, dienogest, induce apoptosis of human primary cultures of adenomyotic stromal cells

Abstract Objectives To investigate the direct effects of progesterone receptor (PR) agonists on proliferation and apoptosis of human adenomyotic cells. Study Design Human primary cultures of adenomyotic stromal cells (ASCs) from 24 patients with adenomyosis were co-treated with estradiol (E2) plus the PR agonists, endogenous progesterone (P) or the synthetic progestin dienogest (DNG), which is used to treat endometriosis. In ASCs, anti-proliferative effects and induction of apoptosis were evaluated in the presence or absence of P (10 −8 –10 −6 M) or DNG (10 −8 –10 −6 M) in culture medium containing E2. Cellular proliferation was analyzed with bromodeoxyuridine incorporation and flow cytometry. Apoptosis was detected with annexin V/7-amino-actinomycin D (7-AAD) staining with flow cytometry and cellular caspase 3/7 activity. Results P and DNG significantly decreased the proportion of cells in the S phase. In addition, both P and DNG increased apoptosis as measured by annexin V-positive/7-AAD -negative cells and caspase 3/7 activity. Conclusions Both endogenous P and synthetic progestin directly inhibited cellular proliferation and induced apoptosis in human ASCs. These pharmacological features of progestational compounds provide insight into the therapeutic strategy for the treatment of adenomyosis.