IGF1 and urinary bladder carcinoma: Because in other tumor models FAK is required for PI3K- and Ras-dependent tumorigenesis [30] and the integrins/FAK complex activates Ras signaling to MAPK [31], [32] a plausible mechanism by which IGF-I promotes migration and invasion of bladder cancer cells would be by activating FAK and the signaling cascade leading to Akt, MAPK and paxillin activation.