October 8, 2013
Sunscreen Helps Protect ‘Superhero’ Gene, Prevents Skin Cancer
Lee Rannals for redOrbit.com – Your Universe Online
Researchers writing in the journal Pigment Cell & Melanoma Research looked at the impact of sunlight on human skin, both with and without sunscreen. They found no evidence of UV-induced skin damage when of sunscreen had been properly applied to an exposed area.
The team determined that not only does sunscreen provide 100 percent protection against the skin cancers, but it also shielded the p53 gene, which works to prevent cancer.
"As soon as our skin becomes sun damaged, the p53 gene goes to work repairing that damage and thereby preventing skin cancer occurring," Lead researcher Dr. Elke Hacker, from Queensland University of Technology's AusSun Research Lab, said in a press release. "But over time if skin is burnt regularly the p53 gene mutates and can no longer do the job it was intended for - it no longer repairs sun damaged skin and without this protection skin cancers are far more likely to occur."
The study involved 57 people undergoing a series of skin biopsies to determine molecular changes to the skin before and after UV exposure and with and without sunscreen. First, the team took small skin biopsies of people's unexposed skin. After this, they exposed two skin sites to a mild burning dose of UV light. One site was covered with sunscreen, while the other was not.
"After 24 hours, we took another set of biopsies and compared the skin samples," Hacker said. "What we found was that, after 24 hours, where the sunscreen had been applied there were no DNA changes to the skin and no impact on the p53 gene."
She said that this study looked beyond the redness of skin to determine whether sunscreen helps prevent molecular changes that have been linked to skin cancers.
This study provides a baseline measurement of molecular responses to UV exposure, so the results can be used to investigate post-sun exposure treatments to assist in the repair of sun-damaged skin.
Cancer Council Queensland spokesperson Katie Clift said the study reinforces how important it is to remember to wear sunscreen.
"Cancer Council Queensland recommends using SPF30 or above broad-spectrum, water-resistant sunscreen, and reapplying sunscreen every two hours," Clift said. "Applying sunscreen correctly is important. Adults should apply more than half a teaspoon of sunscreen to each arm and the face, neck and ears - and just over one teaspoon to each leg, and front and back of the torso. It's also important to complement sunscreen with sun protective clothing, a broad-brimmed hat, to seek shade and slide on wraparound sunglasses for best protection."