ESR1 and prostate cancer: To determine the effects of various ER ligands on the regulation of DHT-induced cell proliferation in endothelial and prostate cancer cells, endothelial HAECs or prostate cancer cells were seeded in 96-well plates and treated with DHT plus or minus various concentrations of αE2, βE2, DES, ICI, genistein, and tamoxifen (Figs. 1–3) for 48 or 72 h, respectively.