Molecular activity of 1,25-dihydroxyvitamin D3 in primary cultures of human prostatic epithelial cells revealed by cDNA microarray analysis.

1,25-Dihydroxyvitamin D(3) [1,25(OH)(2)D(3)] exerts anti-proliferative, differentiating and apoptotic effects on prostatic cells. These activities, in addition to epidemiologic findings that link Vitamin D to prostate cancer risk, support the use of 1,25(OH)(2)D(3) for prevention or therapy of prostate cancer. The molecular mechanisms by which 1,25(OH)(2)D(3) exerts antitumor effects on prostatic cells are not well-defined.

Preclinical activity of ketoconazole in combination with calcitriol or the vitamin D analogue EB 1089 in prostate cancer cells.

Purpose: Ketoconazole is a general inhibitor of P450 enzymes, of which some are necessary for androgen biosynthesis and the metabolism of vitamin D compounds. We tested the growth inhibitory activity of ketoconazole combined with 1,25-dihydroxyvitamin D3 (calcitriol) and with the vitamin D analogue EB 1089 in a preclinical model of prostate cancer.

Materials And Methods: Clonal assays with primary cultures of human prostatic cancer cells were performed to test anti-proliferative effects of ketoconazole alone or in combination with calcitriol or EB 1089.