OBJECTIVES:
* Determine the effect of tocopherol supplementation on plasma and urine levels of α-, γ-, and δ-tocopherols, PSA, and prostaglandin E\_2 by comparing the blood and urine samples collected before and after the supplementation in patients with prostate cancer.
* Test the hypothesis that the supplementation reduced oxidative and nitrosative stress by measuring plasma levels of F\_2-isoprostane, C-reactive protein, and 3-nitrotyrosine as well as urinary levels of 8-hydroxy-2-deoxyguanosine (8-OHdG).
* Determine the levels of α-, γ-, and δ-tocopherols in prostate tissues and analyze immunohistochemically (IHC) for cell proliferation, apoptosis, cyclooxygenase-2, 8-OHdG, and 3-nitropyrosine levels in prostate cancer/tissue slides.
OUTLINE: Patients are randomized into 1 of 3 arms.
* Arm I: Patients receive no supplementation.
* Arm II: Patients receive oral high γ-tocopherol vitamin E supplementation once daily for 1 week.
* Arm III: Patients receive oral high γ-tocopherol vitamin E supplementation once daily for 2 weeks.
Blood, urine, and tissue samples are collected periodically and analyzed for oxidative/nitrosative stress and other markers (i.e., F2-isoprostane, 8-OHdG, 3-nitrotyrosine, prostaglandin E2, C-reactive protein, and PSA), biomarkers in prostate tumors and nontumorous tissues (i.e., 8-OHdG, 3-nitrotyrosine, and cyclooxygenase-2) by IHC, and pharmacokinetics by high-performance liquid chromatography.
