October 24, 2011

expert reaction to new research on the timing of UV exposure and skin cancer in mice, as published in PNAS

This paper presented new evidence that the link between UV light exposure and skin cancer may also be linked to the timing of the exposure.

Professor Brian Diffey, Emeritus Professor of Photobiology, Institute of Cellular Medicine, Newcastle University, said:

“This is a fascinating study in mice showing that their susceptibility to UV exposure in terms of developing skin cancer varies from whether they are exposed in the morning or afternoon. However, any extrapolation to humans is highly speculative and the nature of our exposure to sunlight and other UV sources like sunbeds is subject to many social constraints such as the split between our work and leisure time. This would make it difficult to control our exposure just to specific times of the day, assuming, of course, the findings were at all relevant to humans. Remember it is easy to reduce your risk of skin cancer simply by not using sunbeds and taking care not to overexpose yourself to strong sunshine.”

Dr Kat Arney, science information manager at Cancer Research UK, said:

“Over the past few years, scientists have been gathering evidence showing that DNA repair is linked to the cell’s biological clock, and these new findings in mice support this idea. But we don’t know whether this research will hold up in humans, and we would still advise people to avoid using sunbeds or getting sunburnt at any time of day to reduce the chances of developing skin cancer.”

‘Control of skin cancer by the circadian rhythm’, Sancar et al, published in Proceedings of the National Academy of Sciences on Monday 24 October.