(iVillage Total Health) - Different amounts of antioxidants in the skin in males and females may reveal why men are more prone to certain kinds of skin cancer, say researchers at Ohio State University Medical Center.
Squamous cell carcinoma, the second most common form of skin cancer, occurs more often in men than in women. For years, scientists believed that this was due to lifestyle differences. It was believed that men spend more time outside than women, and are less likely than their female counterparts to use sunscreen. Previous studies have shown that such unprotected sun exposure will increase the risk of squamous cell carcinoma.
Researchers at Ohio State University Medical Center believed that there was more to the increased risk than just increased sun exposure. Dr. Tatiana Oberyszyn, assistant professor of pathology and molecular virology, immunology and medical genetics, and Jennifer Thomas-Ahner, a doctoral student, investigated this theory with an animal study.
The researchers exposed male and female mice to identical amounts of UVB light during two experiments. UVB light is the spectrum of sunlight that is most damaging to the skin, responsible for the redness and swelling of sunburn.
In the first experiment, the mice were subjected to a single exposure of UVB light. The researchers measured the degree of swelling, antioxidant levels, DNA damage and certain enzyme levels in the skin. The male mice demonstrated a weaker inflammatory response, lower overall antioxidant levels and more DNA damage in their skin than the female mice.
In the second experiment, the mice were subjected to sun exposure three times weekly for 16 week. Once the mice were 25 weeks old, the researchers examined them for tumor growth, size and number. The male mice developed tumors earlier than the female mice, and their tumors were generally larger and more aggressive.
Regardless of sun exposure, female mice demonstrated a higher capacity for antioxidants in the skin than male mice. Dr. Oberyszyn has theorized that the greater capacity for naturally occurring antioxidants in females may protect them from a certain degree of tumor growth and spread. However, she stresses the need for more studies to validate these findings.
This study was published in the April issue of Cancer Research.
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