Anti-tumor effects of 1,25-dihydroxyvitamin D-3 and vitamin D analogs

The role of 1,25-dihydloxyvitamin D-3 (1,25-(OH)(2)D-3) as a regulator of c ell growth and differentiation is well recognized. Currently, 1,25-(OH)2D3 and vitamin D analogs are being evaluated for their therapeutic potential i n the treatment 1 of hypelproliferative disorders like cancer. In the prese nt review, we will discuss several processes that might be involved in 1,25 -(OH)(2)D-3- and vitamin D analog-mediated suppression of cancer cell growt h. The effects on turner cell proliferation, differentiation, apoptosis, an giogenesis, metastases, and parathyroid hormone-related peptide secretion w ill be highlighted. In addition, combination therapy with other tumor effec tive drugs will be addressed. Furtermore, we will focus on the potential dr awbacks and the possible side effects of vitamin D compounds in the treatme nt of cancer.