Unlocking the potential-vitamin D in prostate cancer prevention

Figure 1 Illustrates the mechanism of vitamin D₃ activity in prostate cells. Both 25-hydroxyvitamin D₃ [25(OH)D₃] and 1a,25-dihydroxyvitamin D₃ [1a,25(OH)₂D₃] enter the cells. Within the mitochondria, 25(OH)D₃ is transformed into 1a,25(OH)₂D₃ by an enzyme called 25(OH)D-1a-hydroxylase (1a-OHase). When 1a,25(OH)₂D₃ binds to the vitamin D receptor (VDR), the VDR forms a complex with the retinoid X receptor. This complex then attaches to specific vitamin D-response elements in the promoter region of genes responsive to vitamin D₃, leading to the activation of gene transcriptionß. VDR: vitamin D receptor; RXR: retinoid X receptor.