This p53 dependency was unexpected, as we have shown that targeting p65/RELA in a p53 competent KRAS-induced lung cancer mouse model reduces tumorigenesis [23] and loss of IKKβ in a p53 competent RAS-induced melanoma model [26] or in a p53 competent KRAS-induced pancreatic cancer model [27] also reduces tumorigenesis. This evidence concerns the gene RELA and melanoma.