We know that UV light is the main driver of most skin cancers. UV rays from the sun or tanning beds causes mutations in the DNA of skin cells that are the cause of most skin cancers. However we also know that some skin cancers are not related to UV exposure. A link between chronic inflammation and skin cancers has long been recognized. Now a mechanism that may explain this has been elucidated in a recent study. Looking at skin samples from children with a rare skin condition, recessive dystrophic epidermolyisis bullosa investigators found that the skin cancers from the chronic inflammation in this condition were related to over activity of a protein called APOBEC. This protein normally plays a role in adding diversity to cellular proteins and is also thought to help defend against viruses. In chronic inflammation it appears to become overactive causing it to introduce mutations across the genome, some of which eventually lead to cancer.
There is hope that this new knowledge will help investigators work on better preventative strategies for the many cancers (in both skin and other tissues) that are related to chronic inflammation.
APOBEC mutation drives early-onset squamous cell carcinomas in recessive dystrophic epidermolysis bullosa
Raymond J. Cho et al.
Science Translational Medicine 22 Aug 2018: Vol. 10, Issue 455