Scientists have discovered that the skin has a built-in mechanism to protect against cancer, but that it is turned off by excessive sunlight. UV light disrupts the protein YTHDF2, which normally prevents the activation of an immune sensor that causes dangerous inflammation. This protein prevents a small RNA signal from triggering an inflammatory response that could lead to cell damage. When YTHDF2 loses its function, a chain reaction is triggered that turns normal sun damage into a cancer risk. Thus, research shows that overexposure to UV rays can deactivate the skin's natural defenses and increase the likelihood of cancer. This discovery helps to better understand the mechanisms of skin cancer and may lead to new ways of prevention or treatment[1].