Moreover, increased MMP-9 and EGFR activation could be enhancing tumor angiogenesis in the C-IKKα tumors as both molecules are involved in processes required for tumor invasion of tissues and metastasis, such as angiogenesis [52, 53]; they are also positive regulators of VEGF-A expression [41, 42], that predisposes murine epidermis to NMSC development [54, 55] and favor the growth of large and lacunar blood vessels (a prominent feature of skin tumor progression) [56]. This evidence concerns the gene MMP9 and skin neoplasm.