Science: New Discovery in Tanning

Washington Post science writer Rob Stein was online Monday, Oct. 9 at 11 a.m. ET to answer questions about his article: Tan From a Bottle May One Day Protect Against Skin Cancer , which looks at new insights about how natural tanning occurs.

The transcript follows.

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Takoma Park, Md.: People who only looked at the headline or otherwise did not read the whole story may think that the tanning creams currently sold are good for you. I see on page two of the story that they do not contain the chemical discussed in the story, but do they actually do harm? Also, within how many years do the scientists predict that the findings might be complete?

Rob Stein: The self-tanners on the market are not harmful per se but are not protective against the damaging rays of sun exposure or skin cancer. So skin cancer experts worry people may expose themselves to the sun mistakenly thinking they are protected.

The scientists don't know how much research they will have to do, but don't even think they'll be ready to start testing anything on people for another two years.

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Washington, D.C.: Any chance this discovery could lead to any other cancer protecting products -- for other cancers, not just skin?

Rob Stein: At this point the other possible applications for cancer would be skin cancer, and even for that much more research will be needed to determine whether it will pan out for practical applications.

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Washington, D.C.: Your story mentions that UV is actually targeting a different kind of cell than previously thought, so does that mean all the products on the market right now that protect against UV aren't as effective as we think they are?

Rob Stein: No, this does not put into doubt the products that do protect against UV damage. This provides insights into the tanning process, and possibly could lead to new ways to get protection by harnessing the natural tanning process.

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Falls Church, Va.: Fisher's quote at the end of the story mentioned they still have to make sure what he discovered is safe. In your interviews, did he mention if they had seen any side-effects or can you speculate what some of the risks for this new cream could be?

Rob Stein: They haven't seen any side effects. But they really haven't done any safety testing. There's no way to know what kind of risks could be posed, but unexpected side effects do occur frequently in early stages of research. That's why they're saying they have to do a lot more work before they can even be sure it's safe to this approach.

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College Park, Md.: What else has Forskolin been used for? It fascinates me that a scientist in Boston can find such a far-off ingredient for his studies (in this case, the root of a Hindu plant).

Rob Stein: Forskolin has actually been around for a long time. It's a standard tool that scientists have been use in the laboratory to stimulate cAMP production in cells, which is a fundamental cellular process.

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Arlington, Va.: Does the substance in this cream mimic UV rays in the way they affect cells? Did Vitamin E levels change at all, or did the substance just affect pigment?

Rob Stein: The cream mimicked UV's effect on cell only inasmuch as it stimulates pigment production.

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Washington, D.C.: Are the scientists on this project working with or for any major cosmetics or pharmaceutical company? If not, are they likely to transform their work into their own product line?

Rob Stein: The lead scientist involved in the work has formed his own small biotech company to try to commercialize this approach.

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Silver Spring: Interesting article Rob. In light of the article in last week's Health section, "Quick Study, Prostate Cancer, Hormone therapy may increase risk for other diseases," I suspect this tanning treatment also has the potential to pose an increased risk for other diseases. The reason for this, is that the scientists are using forskolin to activate cAMP, and cAMP is a "second messenger" in many metabolic pathways involving hormones. Thus, there would seem to be a strong potential to also affect pathways other than the intended "tanning pathway," and consequently produce other metabolic effects which could lead to disease. Do you know how the researchers intend to avoid this potential problem, and do you have any thoughts on this issue?

washingtonpost.com: Quick Study , Oct. 3.

Rob Stein: Yes, that's an excellent point, and one of the reasons the researchers are saying no one should try applying forskolin to their skin for tanning. A lot of research is needed to see if this approach is safe. It could very well turn out that this is not safe, but that the research provides insights that lead scientists to other strategies that are.

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Pale in Silver Spring, Md.: I have polymorphic light eruptions (hives when skin is exposed to sun) and have tried "self tanners" with DHA to somewhat successfully prevent the horrible rash. Could forskolin help prevent PLE? Thanks.

Rob Stein: The researchers made it clear that no one should try using forskolin as a skin cream for anything yet because it's not clear it would be safe for any purpose.

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Baltimore, Md.: Do you think this offers any hope to people who have vitiligo (the skin disorder that affects 1-2 percent of the population where they lose their pigment in their skin)?

Thank you for your response!

Rob Stein: It would depend on what the underlying malfunction is. The approach only bypasses on problem -- a faulty receptor for the MSH hormone.

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Falls Church, Va.: Were there other discoveries about Tanning from Fisher's research that didn't make it into your article?

Rob Stein: His lab is working on other related work but this was the most recent findings published.

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Rob Stein: Regarding the earlier question about vitiligo. I just got this answer back from Dr. Fisher: "Unfortunately the problem in vitiligo is lack of melanocytes, rather than lack of pigment in viable melanocytes. Therefore it's not clear that our strategy would work. However it is conceivable that there may be strategies in the future which combine growth inducers for melanocytes with differentiation inducers (like ours)."

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Vienna, Va.: Dear Mr. Stein,

Do you know if this artificial tanning is likely to reduce the skin's ability to produce Vitamin D?

Rob Stein: Dr. Fisher says any vitamin D issue could be overcome with supplements.

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Rob Stein: Thanks very much to everyone for participating. Lots of really good questions.

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