Expression of estrogen receptor β in prostate carcinoma cells inhibits invasion and proliferation and triggers apoptosis

The involvement of estrogen receptor beta (ER) in prostate carcinogenesis has been hypothesized. Several reports have shown that ER expression was decreased when prostate cells undergo neoplastic transformation, suggesting that it could play a tumor-suppressor role. By restoring ER expression in prostatic carcinoma cells by adenoviral delivery, we aimed to test this hypothesis. We observed that ER strongly inhibited the invasiveness and the growth of these cells. In addition, ER cells were undergoing apoptosis, as shown by quantification of Bax, Poly(ADP-ribose) polymerase and caspase-3 expression. Our data suggest that ER acts as a tumor-suppressor by its anti-proliferative, anti-invasive and pro-apoptotic properties. (C) 2004 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.