Research is shedding new light on sunscreens that might someday prevent or treat skin cancer by reversing dangerous gene mutations caused by overexposure to the sun.
Working with hairless mice, researchers found that a synthetic compound called CP-31398 helped stabilise damage in the tumour-suppressing p53 gene. This type of damage occurs in humans and mice alike after sustained exposure to the sun's ultraviolet B (UVB) rays.
Once treated and repaired, the UVB-exposed p53 mouse gene resumed its normal cancer-preventing activity, inhibiting the spread and proliferation of tumour cells.
"Once the skin is exposed to UVB it leads to mutations in the p53 gene, and it becomes non-functional, and then you see induction of skin cancer," explained study lead author Mohammad Athar, a professor of dermatology at the University of Alabama, Birmingham.
"But this compound we used interacts with the p53 mutant genes and converts them back into functional genes," he said. "And that led to less incidence of skin cancer tumours, fewer numbers of tumours, and slower tumour growth in the UVB-exposed mice populations we tested."
Athar's findings are published in the December issue of The Journal of Clinical Investigation.
Gene also present in other cancers
Athar pointed out that p53 mutations linked to skin cancer are also present in more than half of all tumour types, so the current work could theoretically lead to cancer prevention applications for a range of diseases beyond melanoma.
"We tested UVB-signature mutations, but every cancer-causing agent that interacts with p53 has its own form of mutation," he noted. "So, we need to see if different types of cancers can be attenuated with this type of compound."
In the interim, Dr Robin Ashinoff , the medical director of dermatologic, mohs and laser surgery at Hackensack University Medical Centre in Hackensack, N.J., said that the current findings should be viewed with a mix of interest and caution.
"This still needs to be studied in human trials in a placebo-controlled fashion," she noted. "And bringing this kind of technology to market is always a long road."
"But if we can work at the genetic level to try and prevent skin cancer where it starts and correct and suppress the abnormal clones that arise from UVB exposure, that would certainly be quite advantageous," she added. "And it would be wonderful to be able to put this approach into a cream or a sunblock. That - when it happens - will certainly become the new gold standard." - (Alan Mozes/HealthDay News)
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