A Randomized Study to Investigate the Presence of Tocopherol Metabolites in the Prostate
Trial Snapshot
- Phase
- Phase 1
- Status
- Completed
- Enrollment
- 65
- Locations
- 2
- Primary Endpoint
- Effect of tocopherol supplementation on plasma and urine levels of α-, γ-, and δ-tocopherols, PSA, and prostaglandin E2
Study Overview
Brief Summary
RATIONALE: Vitamin E supplements may stop or delay the development of prostate cancer in patients who are at risk of prostate cancer or who have prostate cancer. It is not yet known which vitamin E regimen is more effective in preventing prostate cancer.
PURPOSE: This randomized phase I trial is comparing vitamin E supplement regimens to see how well they work in preventing cancer in patients at risk of prostate cancer or who have prostate cancer.
Detailed Description
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.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Parallel
- Primary Purpose
- Prevention
- Masking
- None
Eligibility Criteria
- Ages
- 18 Years to — (Adult, Older Adult)
- Sex
- Male
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- Not provided
Exclusion Criteria
- Not provided
Outcomes
Primary Outcomes
Effect of tocopherol supplementation on plasma and urine levels of α-, γ-, and δ-tocopherols, PSA, and prostaglandin E2
Time Frame: 4 years
Oxidative stress and nitrosative stress as assessed by plasma levels of F2-isoprostane, C-reactive protein, and 3-nitrotyrosine as well as urinary levels of 8-hydroxy-2-deoxyguanosine (8-OHdG)
Time Frame: 4 years
Levels of α-, γ-, and δ-tocopherols in prostate tissues and cell proliferation, apoptosis, cyclooxygenase-2, 8-OHdG, and 3-nitropyrosine levels as assessed by IHC
Time Frame: 4 years
Secondary Outcomes
No secondary outcomes reported