Selenium May Prevent High-Risk Bladder Cancer

Margaret R. Karagas, Ph.D.
Dartmouth Medical School
NIEHS Grant P42ES007373

NIEHS-supported grantees at Dartmouth Medical School report in a new study that selenium may help prevent high-risk bladder cancer. The study found that women, moderate smokers, and people p53 positive tumors showed significant reductions in bladder cancer with higher selenium intake.

In the US, bladder cancer is the fourth most common cancer among men and twelfth most common among women with approximately 67,000 cases being diagnosed each year. About 13,000 deaths are expected this year from bladder cancer. Bladder cancer develops through different pathways, but one of the major paths is through alterations in the p53 gene. These cancers are associated with more advanced disease.

The study involved 857 people with newly diagnosed bladder cancer. Selenium intake was measured by analyzing toenail clippings. Cancer risk was reduced between 30 and 50 percent in the three groups as selenium intake increased.

The exact mechanism by which selenium inhibits carcinogenesis is unknown, but it may occur through several mechanisms including reducing oxidative stress and inflammation, enhanced immune responses, activation of DNA repair genes, etc. The results of this study may provide clues on how to prevent tumors from developing and potentially lead to new chemotherapeutic agents.

Citation: Wallace K, Kelsey KT, Schned A, Morris JS, Andrew AS, Karagas MR. Selenium and risk of bladder cancer: a population-based case-control study. Cancer Prev Res (Phila Pa). 2009 Jan;2(1):70-3.