Green Tea Blocks Benefits Of Cancer Drug

Note that green tea might be effective in reducing the probability of getting cancer to start out, with w/o contradicting this study.

http://www.sciencedaily.com/releases/2009/02/090203162355.htm

ScienceDaily (Feb. 5, 2009) — Contrary to popular assumptions about the health benefits of green tea, researchers at the University of Southern California (USC) have found that the widely used supplement renders a cancer drug used to treat multiple myeloma and mantle cell lymphoma completely ineffective in treating cancer.

The study, which found that a component of green tea extract (GTE) called EGCG destroys any anticancer activity of the drug Velcade in tumor-bearing mice, will be published in the journal Blood.

"Our finding that GTE or EGCG blocked the therapeutic action of Velcade was completely unexpected," says lead author Axel H. Schönthal, PhD, associate professor in the Department of Microbiology and Immunology at the Keck School of Medicine of USC. "Our hypothesis was that GTE or EGCG would enhance the anti-tumor effects of Velcade, and that a combination of GTE with Velcade (or EGCG with Velcade) would turn out to be a superior cancer treatment as compared to treatment with Velcade alone."
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Schönthal points out that for patients on Velcade, supplementing with green tea products should reduce the burden of harsh side effects—which might be attractive to the patient, but comes at a high cost.

"Essentially, in addition to not being able to attack tumor cells, Velcade would be unable to cause side effects either," he says. "As a result, the patient would feel a lot better and conclude that the consumption of GTE helped cope with side effects—while in reality, Velcade simply wasn't active in the first place."