Triciferol acts as a multiple ligand with combined VDR agonist and HDAC antagonist activities. Triciferol binds directly to the VDR ( IC 50 =87 nM), and functions as an agonist with 1,25D-like potency on several 1,25D target genes. Triciferol induces marked tubulin hyperacetylation, and augments histone acetylation. Triciferol also exhibits efficacious antiproliferative and cytotoxic activities in cancer cell models in vitro [1].

Triciferol (0-10000 nM; 0-72 hours) is significantly more potent in suppressing the proliferation of estrogen receptor-negative human MDA-MB231 breast cancer cells [1]. Treatment of MCF-7 cells with Triciferol (100-1000 nM) induces ≈2.5-fold higher rates of cell death than equimolar amounts of 1,25D [1]. Cell Proliferation Assay [1] Cell Line: MDA-MB231 breast cancer cells Concentration: 0-10000 nM Incubation Time: 0-72 hours Result: Growth inhibition was statistically significantly different from that of 1,25D at concentrations of 1 nM or above.