March 15, 2004 -- A powerful antioxidant found in green tea may be responsible for the beverage's heralded anticancer benefits.
New research shows that the antioxidant, known as EGCG, binds to a protein found on tumor cells and dramatically slows their growth.
Researchers say previous studies have shown that green tea helps protect against a variety of cancers, such as lung, prostate, and breast, but the mechanisms for these effects are not known.
In the study, published in the April issue of Nature Structural & Molecular Biology, researchers identified a potential target for the antitumor action of EGCG on human lung cancer cells that inhibited cancer cells' growth. By learning more about this target, researcher may be able to develop new treatments that maximize green tea's cancer-fighting potential.
Explaining Green Tea's Anticancer Benefits
In order to better understand how the antioxidants found in green tea may protect against cancer, researchers looked at how they affected a protein found on the surface of cancer cells called laminin receptor.
The study showed that when cancer cells with this protein were treated with polyphenol EGCG, the growth of the tumor cells was significantly reduced.
Researchers say the concentration of the antioxidant required to produce these anticancer effects was equivalent to those found in the body after drinking only two to three cups of green tea.
Other components found in green tea, including caffeine, had no effect on tumor cell growth.
Researchers say the results further the understanding of how antioxidants interact with cancer cells and may one day lead to more effective cancer therapies that use green tea as a dietary cancer treatment.