Interestingly,SIRT1 knockout mice, which do not live longer when calorically restricted, werefound to have normal rates of skin cancer but the ability of resveratrol, aSIRT1 activator, to protect the mice was greatly reduced [113], indicating thatthe anti-tumor activity of resveratrol is mediated at least in part by SIRT1. Here, SIRT1 is linked to skin cancer.