This study will enroll 80 (40 per study arm) subjects (\>18 years of age), recently diagnosed with prostate cancer (histologically documented adenocarcinoma of the prostate), who are scheduled to undergo prostatectomy.
Eligible subjects will be recruited in the Urology Clinic at MUSC or Ralph H. Johnson VAMC. All subjects will be refered to the study by their Urologist. At the baseline visit, consent will be obtained before any study procedures are initiated. A blood sample will be obtained for 25(OH)D3 analysis. Subjects will be randomized to either the intervention group (vitamin D3 4000 IU daily) or the placebo group and take the study medication for approximately two months before their scheduled prostatectomy. The final study visit is the day of surgery. A blood sample for 25(OH)D3 analysis will be obtained. Prostate tissue will be collected from the Pathologist for (a) genomics (RNA sequencing) analysis; (b) proteomics (proteins, glycons and lipids) analysis and (c) Vitamin D Receptor (VDR) by immunohistochemistry.