Role of Vitamin D deficiency and mRNA expression of VDR and RXR in haematological cancers.

Vitamin D has a crucial role in cancer control and prevention. For its activity, VDR (vitamin D receptor) and its heterodimer RXR (Retinoid X receptor) are equally important in the cell. This ligand (vitamin D) and receptors (VDR-RXR) complex together triggers downstream DNA damage response in the cell and thus counters cancer in blood. 137 patients and 60 disease free controls were recruited for this study. The levels of vitamin D in patient and controls were analysed and compared using ELISA. The mRNA expression of the two receptor genes; VDR and RXR was also assessed by RT-PCR, to see their role in haematological malignancies. Their expression levels were corelated with the vitamin D levels in individuals to understand their mutual contribution in blood cancer prevention. The results confirmed a highly significant correlation between vitamin D levels of patients and controls (p < 0.001). The study also revealed that age of patients is a critical factor in determining the relative risk of blood cancer (p < 0.001), its types (leukaemia and lymphoma) and subtypes. Also, the mRNA expression of VDR showed a positive and non-significant relationship with vitamin D levels and RXR expression (p > 0.05). Based on our findings, and studies on other diseases it can be inferred that Vitamin D deficiency and dysregulation of its associated receptors may lead to cancer initiation and/or progression by failing to trigger the cellular DNA damage repair machinery.