A system by which skin cells damaged by the Sun commit suicide to prevent cancer has been described by scientists in the US. The findings may shed light on why certain people are more susceptible to skin cancer caused by the Sun and thus help in the development of new treatments.
Scientists from the University of Texas subjected two groups of shaved mice to ultraviolet light, one of which lacked a particular protein thought to be linked to cell suicide. They found far fewer "sunburn cells" - cells undergoing suicide in response to UV light - in mice missing the protein.
Further tests showed that 70 per cent of the protein-deficient mice accumulated potentially cancerous cell mutations in their skin after long exposure to UV rays. Only 5 per cent of the "normal" mice which had the protein accumulated the mutations, according to results published in Science. Researchers, led by Laurie Hill, concluded that molecular interactions involving the cell-suicide protein were "pivotal" in the growth and spread of sunlight-induced skin tumours.
Dr Tony Quinn, of the Imperial Cancer Research Fund's skin tumour laboratory in London, said: "What the research suggests is that, if this pathway is disturbed, it may be a way that cancer can occur. It could explain why some people are more at risk from sunlight. The study does not imply that sunburn helped prevent skin cancer."