Selenium Turns on Cancer-Suppressing Gene

A new study indicates researchers may have solved the mystery behind selenium's anti-cancer mechanism.

In a study published in the Proceedings of the National Academy of Sciences, researchers report that selenomethionine, a form of selenium, activates p53, what scientists call the tumor-suppressing gene. Gene p53 halts tumor development by triggering apoptosis–cell death–in cancer cells. Many cancer patients have an abnormal or inactive p53 gene.

The study authors used human lung cancer cells from which p53 genes were absent. They then introduced the gene into the cells and treated some of the cells with selenomethionine. The researchers found that selenomethionine did indeed increase p53 activity–but only if a compound called Ref1 was present. When the researchers eliminated Ref1 from cells, p53 was not activated. The researchers concluded that selenium targets p53. The authors recommended people take 200 mcg of selenium daily for cancer prevention.

In an interview with Reuters Health, the researchers also pointed out that most Americans do not consume the recommended 50 micrograms per day of selenium and that multivitamins are a good idea for most people.

Reference:

Seo YR, Kelley MR, Smith ML. Selenomethionine regulation of p53 by a ref1-dependent redox mechanism. Proc Natl Acad Sci U S A. 2002 Sep 30; [epub ahead of print].