Abstract
1,25-Dihydroxyvitamin D3, the biologically active form of vitamin D, in addition to regulating calcium homeostasis, also has antiproliferative and prodifferentiating effects.Most studies concerning the therapeutic potential of analogs of 1,25(OH)2D3, which are antiproliferative and prodifferentiating but do not cause hypercalcemia, have been done using leukemic cells.Recent evidence from both in vivo and {tiin vitro} studies has indicated that 1,25(OH)2D3 or analogs of 1,25(OH)2D3 can inhibit the growth of breast cancer cells, thus suggesting the therapeutic potential of analogs of 1,25(OH)2D3 in the treatment of breast cancer.