RAC1 and urinary bladder cancer: In our study, we confirmed that upon EGF induction, SHCBP1 translocates to the nucleus, where it binds to RACGAP1 through its N-terminal domain of amino acids 1 ~ 428, and inhibits the GAP activity of RACGAP1 toward RAC1, causing accelerated EGF-induced cell spreading and increased invasiveness of bladder cancer cells.