PHILADELPHIA -- Drinking a nice warm cup of green tea has long been touted for its healthful benefits, both real and anecdotal. But now researchers have found that a component of green tea, combined with low doses of a COX-2 inhibitor, could slow the spread of human prostate cancer.
In the March 1 issue of Clinical Cancer Research, researchers from University of Wisconsin-Madison demonstrate that low doses of the COX-2 inhibitor celecoxib, administered with a green tea polyphenol called pigallocatechin-3-gallate (EGCG), can slow the growth of human prostate cancer. Their experiments were performed in cell cultures and in a mouse model for the disease.
Celecoxib and green tea have a synergistic effect -- each triggering cellular pathways that, combined, are more powerful than either agent alone, said Hasan Mukhtar, Ph.D., professor of dermatology at the University of Wisconsin and member of Wisconsins Paul Carbone Comprehensive Cancer Center. We hope that a clinical trial could lead to a preventative treatment as simple as tea time.
Previous research has linked the cyclooxygenase-2 enzyme, commonly known as COX-2, to many cancer types, including prostate cancer, said Mukhtar. Mukhtar and his colleagues have previously shown COX-2 inhibitors like celecoxib (known under the brand name Celebrex) suppress prostate cancer in animal models. COX-2 inhibitors also have been shown to cause adverse cardiovascular effects when administered at high doses over long durations.
In 2004, Mukhtar and his colleagues demonstrated that green tea polyphenol EGCG has cancer-fighting abilities of its own. Their study, published in Cancer Research, showed that EGCG can modulate the insulin-like growth factor-1 (IGF-1)-driven molecular pathway in a mouse model for human prostate cancer, pushing the cells toward programmed cell death (apoptosis).