Drugstore shelves overflow with personal-care items that promise fresher breath, smoother skin, and now a more startling claim: cancer prevention.
Stada, a German company, sells sunscreen and lotion in Europe containing photolyase, an enzyme that fixes certain DNA errors that can lead to mutations. In a 2000 study, researchers showed that a photolyase lotion reduces the number of such errors in the skin, although no tests have yet been conducted to show it reduces the incidence of skin cancer.
Taking a related approach, AGI Dermatics of Freeport, New York, makes fatty spheres that carry DNA-repair enzymes into skin cells. A published clinical trial indicates that these enzymes can prevent about one-third of skin cancers in people with a hereditary susceptibility to such cancers. AGI Dermatics currently supplies American cosmetics companies with similar enzymes, whose possible therapeutic value has not been tested. They typically show up on ingredient labels as "plankton extract" or "micrococcus lysate."
Meanwhile, Introgen, a biotech firm in Austin, Texas, has signed an agreement with Colgate-Palmolive to develop mouthwashes that prevent oral cancer. Introgen is evaluating a product that administers a dose of the protein p53, known to suppress tumor growth. A clinical trial is under way, but the product faces serious hurdles. It uses a live virus to make the protein—a method the FDA has yet to approve for any drug.