title: The relationship between the vitamin D system and cancer.
abstract: The classic function of 1,25-dihydroxyvitamin D3, the hormonally active form of vitamin D, is the maintenance of normal levels of calcium and phosphorus in the blood. 1,25-Dihydroxyvitamin D3 binds to a specific receptor protein and exerts its biologic action by a mechanism analogous to that proposed for other steroid hormones, that is, the receptor-ligand complex acts on the chromatin to induce transcription of specific genes. Intracellular receptors that bind 1,25-dihydroxyvitamin D3 with high affinity have been found in a large number of tumor cell lines examined as melanoma, osteosarcoma, and human breast and colonic carcinoma cells. The 1,25-dihydroxyvitamin D3 receptor in these cells has characteristics similar to the receptor in bone and intestine, the known target tissues of the hormone. In fact, 1,25-dihydroxyvitamin D3 inhibits the proliferation of melanoma, osteosarcoma, and breast carcinoma cells. More recently, 1,25-dihydroxyvitamin D3 has been shown to suppress the growth and induce monocytic differentiation of murine and human myeloid leukemia cells in vitro. These results point to a previously unsuspected involvement of vitamin D in cell proliferation and differentiation and suggest that analogs of the vitamin D hormone may be of interest as possible therapeutic agents in the treatment of malignancy.
mesh_terms: D002117:Calcitriol / Q000627:therapeutic use; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D006801:Humans; D007668:Kidney / Q000378:metabolism; D009369:Neoplasms / Q000209:etiology / Q000473:pathology*; D018167:Receptors, Calcitriol; D011987:Receptors, Steroid / Q000378:metabolism; D014807:Vitamin D / Q000378:metabolism* / Q000627:therapeutic use; D014808:Vitamin D Deficiency / Q000150:complications
chemical_list: D018167:Receptors, Calcitriol; D011987:Receptors, Steroid; D014807:Vitamin D; D002117:Calcitriol