Topical Tea May Reduce Skin Cancer Risk

AUSTIN, Minn.--By blocking a specific enzyme in the skin, tea polyphenols may be able to reduce the risk of skin cancer, the most common cancer in the United States. Researchers from the University of Minnesota in Austin found a topical cream made with tea polyphenols may work alone or combined with sunscreen to maximize cancer protection. Their presentation was given at the 226th national meeting of the American Chemical Society (www.chemistry.org), held Sept. 7 to 11 in New York.

"We feel this is an important step in improving the prevention of skin cancer," said Zigang Dong, M.D., Dr.P.H., lead researcher. "Topical application of certain tea polyphenols appears to block a key process that leads to skin cancer."

In a mouse model of skin cancer, researchers found topically applied green tea polyphenols decreased levels of JNK-2, an enzyme known to increase in the skin after sun exposure and increase the chance that cancer will develop. By reducing JNK-2, the skin's response to UV light was delayed or blocked. Researchers added there may be additional mechanisms behind tea's protective effects, but further investigation will be needed to determine what they are.

Dong and his team are working to create a cream that contains tea polyphenols and will protect against skin cancer. The cream is being designed for application after exposure to excessive sun. Some skin creams on the market already contain tea polyphenols, although, according to Dong, these products are unlikely to have undergone testing and may contain non-uniform amounts of tea antioxidants.

Previous research has indicated tea consumption may also protect against skin cancer (Cancer Res, 61, 13:5002-9, 2001), although Dong stated topical application is probably a better approach. "Drinking tea may help, but you'd have to drink a large amount to [have it] accumulate in the skin, perhaps as many as 10 cups a day," he said. "It's easier to concentrate it in a cream form, and it's probably more effective."