Association between alpha-tocopherol, gamma-tocopherol, selenium, and subsequent prostate cancer

Area of Science:

• Nutritional Science
• Oncology
• Epidemiology

Background:

• Prostate cancer risk may be influenced by selenium and alpha-tocopherol (vitamin E).
• Gamma-tocopherol, a major dietary form of vitamin E, has been understudied in relation to prostate cancer.
• This study investigated the roles of gamma-tocopherol, alpha-tocopherol, and selenium in prostate cancer development.

Purpose of the Study:

• To examine the association between serum concentrations of gamma-tocopherol, alpha-tocopherol, and selenium and the risk of developing prostate cancer.
• To determine if gamma-tocopherol plays a significant role in prostate cancer risk, independent of or in conjunction with alpha-tocopherol and selenium.

Main Methods:

• A nested case-control study involving 117 prostate cancer cases and 233 matched controls from a blood specimen bank established in 1989.
• Assays were performed on toenail and plasma samples to measure selenium, alpha-tocopherol, and gamma-tocopherol concentrations.
• Conditional logistic regression analysis was used to assess the association between micronutrient levels and prostate cancer incidence.

Main Results:

• Increasing concentrations of gamma-tocopherol showed a significant inverse association with prostate cancer risk (P(trend) =.002).
• Men in the highest fifth of gamma-tocopherol had a fivefold reduced risk compared to the lowest fifth.
• While alpha-tocopherol and selenium showed protective trends, significant associations were only observed when gamma-tocopherol levels were high, suggesting an interaction.

Conclusions:

• Gamma-tocopherol demonstrates a strong protective association with prostate cancer risk.
• The combined use of alpha-tocopherol, gamma-tocopherol, and selenium warrants consideration for future prostate cancer prevention strategies.
• Further research into the synergistic effects of these micronutrients is recommended.