Scientists have figured out how caffeine can protect against skin cancer. This finding could lead to better sunscreens.
The research conducted on mice concluded that caffeine changes the activity of a gene involved in the destruction of cells that have DNA damage and are more likely to become cancerous. Science claims this will lead to new ways of preventing skin cancer. This does not mean coffee lovers are better protected against skin cancer.
Skin cancer is common in our society. According to Cancer Research UK, around 100,000 cases of non-melanoma were registered in the UK in 2008, and just under 12,000 cases of the more dangerous malignant melanoma. These forms of cancers can be caused by over-exposure to ultraviolet light from the sun, which can damage the DNA of skin cells, leading to errors when the cells divide.
Previous studies have found that caffeine has a protective role. Allan Conney of the department of chemical biology at Rutgers University in New Jersey wanted to find the specific molecular mechanisms behind it. He suspected that the response might involve a gene called ATR, which is suppressed when caffeine molecules are present. This suppression encourages the death of DNA damaged cells on the skin.
Conney tested the idea by creating genetically modified mice whose ATR genes were deficient and exposing them to ultraviolet light until they skin developed cancer. After 19 weeks of UV exposure, he found that these mice developed 69% fewer tumours than those that had fully functioning ATR genes. In addition, tumors in the genetically modified mice developed three weeks later than in standard mice.
After 34 weeks of UV exposure, all the mice had developed tumors of non-melanoma cancer called squamous cell carcinoma (SCC). The results were published on Monday in the Proceedings of the National Academy of Sciences.
All of this suggests the possibility that caffeine, possibly applied to the skin, would have an inhibitory effect on sunlight-induced skin cancer," said Conney. "In addition to the effects on the ATR pathway, caffeine also has sunscreening properties."