These features suggest the predisposition towards malignant transformation of keratinocytes overexpressing IKKα, and agree with our previous data showing that K5-IKKα transgenic mice presented an enhanced malignant potential for developing skin tumors [11]; they are also in accordance with our previous results showing the more aggressive phenotype of skin carcinomas arisen in immunodeficient mice injected with PDVC57 tumoral keratinocytes overexpressing IKKα [12]. This evidence concerns the gene KRT5 and skin neoplasm.