Bikle: Sunlight, ultraviolet light is important for the production of vitamin D in the skin. We know from the work now that I've done and others, that the skin only makes this hormone from vitamin D that's produced in the skin, but it also responds to this hormone in terms of promoting differentiation. Well, the problem with cancer is it's a state where differentiation fails. So the question is, if people are not making vitamin D within their skin and not converting that vitamin D in the skin to this hormone, are they more susceptible to developing skin cancer from whatever cause – chemicals or ultraviolet light?
Narrator: Bikle and colleagues at the San Francisco Veterans Affairs Medical Center will study this link further. For Science Today, I'm Larissa Branin.