Avoid green tea during Velcade cancer therapy

Los Angeles, February 4: A new study suggests that the so called tumor-fighting green tea makes bortezomib, a relatively newer cancerdefine drug completely ineffective in treating the disease.

The bortezomib also known as Velcade is used to treat multiple myeloma, mantle cell lymphoma or the brain cancerdefine glioblastoma.

Green tea is known for its potential to lower the chances of developing certain types of cancer. But the researchers at the University of Southern California (USC) found that its polyphenols rather negate the efficacy of the drug, which carries the same purpose.

The study lead author Axel H. Schönthal, PhD, associate professor in the Department of Microbiology and Immunologydefine at the Keck School of Medicine of USC said, "Our finding that green tea extract (GTE) or EGCG blocked the therapeutic action of Velcade was completely unexpected; 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."

The researchers used preclinical models and tumor-bearing mice to study the effects of green tea and Velcade. The researchers found that the chemical interaction between molecules caused unusual effective blockage in Velcade's therapeutic activity. They said that the molecule of both EGCG and the Velcade were able to form chemical bonds and the Velcade molecule could no longer bind to its proposed aim inside the tumor cells.

Schönthal said, "The most immediate conclusion from our study is the strong advice that patients undergoing cancer therapy with Velcade must avoid green tea, and in particular all of its concentrated products that are freely available from health food stores."

"It is important to spread this message to health care providers who administer Velcade to patients," he added.

The study is funded by the Multiple Myeloma Research Foundation. It will be published in a future print edition of the journal, Blood.