The Role of Vitamin D and Vitamin D Receptors in Colon Cancer

Epidemiological studies have demonstrated that vitamin D deficiency is associated with various human cancers. Vitamin D receptor (VDR) regulates most of the biological actions of the active vitamin D metabolite, 1 alpha, 25-dihydroxyvitamin D-3 (1,25(OH)(2)D-3). VDR is highly expressed in small intestine and colon and has critical regulatory actions for proliferation and differentiation, intestinal barrier function, innate immunity, and host defense in the gut. Evidence strongly suggests the protective effects of vitamin D and VDR on colorectal cancer. In this review, we will cover the recent progress of vitamin D/VDR in the genetic regulation, immunity, protein expression, and microbiome, in colon cancer. We will discuss the potential clinical application of vitamin D/VDR in prevention and treatment of colon cancer.