In this study, we demonstrate that its precursor, 25(OH)D3, decreased cell count and viability, induced apoptotic cell death, and upregulated the gene and protein expression of VDMS enzymes (CYP27B1 and CYP24A1) and receptor (VDR) in the HeLa adenocarcinoma cell line. The gene discussed is CYP27B1; the disease is adenocarcinoma.