CYP24A1 and colorectal cancer: In colorectal cancer, VDR mRNA levels are decreased in the tumour tissue compared with the adjacent mucosa,18 while in breast cancer reports are contradictory.37, 39, 40, 41 Under high vitamin D3 diet, VDR protein expression was significantly (p < 0.01,) increased in tumours overexpressing CYP24A1 compared with control, and this effect was independent of dietary soy (Supporting Information Fig. S4).