HUMAN PROSTATE-CANCER CELLS - INHIBITION OF PROLIFERATION BY VITAMIN-D ANALOGS

1,25-Dihydroxyvitamin D [1,25(OH)(2)D-3, calcitriol] can inhibit the proliferation of some human prostate cancer cells but its clinical use is limited by hypercalcemia. We therefore explored the bioactivity of less calcemic vitamin D analogs. We studied the effects of calcitriol and 3 synthetic analogs at concentrations of 10(-6) to :1O(-12) M on the in vitro proliferation of 3 human prostate carcinoma cell lines: DU 145, PC-3, and LNCaP. Calcitriol and analogs showed significant antiproliferative activity on PC-3 and LNCaP cells. DU 145 cells were inhibited by the analogs only. We conclude that vitamin D analogs warrant further investigation as therapeutic agents in prostate cancer.