The Effect of Cholecalciferol on Apoptotic Signalling Pathway in Cancer Cells.

Recently, the pleiotropic extraskeletal effects of vitamin D have received more attention in addition to its well-known importance for bone health. Research suggests that vitamin D deficiency is as associated with the risk of developing various malignancies. Increased expression of vitamin D receptors and vitamin D metabolism enzymes is observed in cancer cells. There is growing evidence that vitamin D exhibits anticancer activity via different pathways, for example, inhibition of proliferation or induction of cell apoptosis. The aim of this work was to evaluate the effect of vitamin D (in the form of cholecalciferol) on viability and relative expression of apoptosis regulators BAX and Bcl-2 in human cervical cancer cell line HeLa. Experimental cultures in eighth passage were treated with 1300 nM and 130 nM cholecalciferol for 24 hr. Viability of the cells was analysed by flow cytometry and relative expression of BAX and Bcl-2 proteins by western blotting. Our preliminary results showed that viability of HeLa cells after cholecalciferol treatment did not change significantly compared to the control condition. The amount of BAX protein decreased more in cholecalciferol-treated cells compared to the control condition, but no significant difference was observed. HeLa cells treated with cholecalciferol also indicated slight alteration in Bcl-2 expression and BAX/Bcl-2 ratio without statistical significance. In conclusion, the treatment of HeLa cells with cholecalciferol at the used concentrations did not have a significant effect on the apoptotic signalling pathway. [ABSTRACT FROM AUTHOR]