Cdc42, which belongs to the Rho family [127], takes part in the initiation of most human cancers [21,128] since it induces the proliferation of Ras-transformed carcinogenic cells by inducing cell cycle progression [129], as well as stimulates tumorigenesis through impeding the degradation of EGFR by ubiquitin-proteasome system [128,130]. This evidence concerns the gene CDC42 and cancer.