Natural Tanning May Inhibit Skin Cancer

While research has highlighted the correlation between tanning and skin cancer, a Harvard study published last week describes a way to stimulate a natural tanning process that reduces the risk of skin cancer, or melanoma.

The study points to the possibility of creating a drug that increases the production of melanin—a natural substance that causes pigmentation in hair and skin—in fair-skinned individuals, inducing these people to tan as a cancer prevention strategy.

Melanin naturally blocks ultraviolet radiation, which is known to cause melanoma.

Harvard Medical School Professor David E. Fisher—who was the lead researcher of the study—identified the regulator of melanin production as the enzyme PDE-4D3.

“When we studied how PDE worked, it became immediately clear to us exactly that it was the mechanism blocking pigmentation,” said Fisher, who also directs the Massachusetts General Hospital’s Department of Dermatology.

“If you were designing a way to auto-regulate an enzyme, it would make perfect sense to limit the pigmentation response to go out of control,” he added.

Studying a group of genetically-altered mice with fair skin and red hair, the researchers identified PDE-4D3 as a “molecular switch” that inhibits the protein—cyclic AMP (cAMP)—that causes pigmentation. The researchers discovered that a drug may be able to induce pigmentation by obstructing PDE-4D3’s inhibition of cAMP.

“By coincidence, this is something that can be druggable,” Fisher said.

According to Fisher, the ideal drug would be directly applied to the skin. Compared to oral medications, topical drugs have relatively minor side effects and avoid potential damage to vital organs.

He added that such a drug should be seen “not [as] a cosmetic one, but a skin cancer protection strategy,” and that the target population of the drug would primarily comprise people with fair skin who have difficulty tanning or who sunburn easily.

Researchers said they hope the potential drug will deter people from engaging in behaviors that increase the possibility of skin cancer, including artificial tanning.

“Melanoma is undergoing an increase greater than any other cancer in America,” Fisher said, calling the trend “an extremely frustrating statistic” in light of readily available knowledge about UV exposure’s correlation with skin cancer.

Fisher added that the drug could be developed within the next five to 10 years.