ARHGAP1 and colorectal cancer: As previous research had determined that a DLC1 mutant with a 29 amino acid deletion (amino acids 929–957) in the START domain had decreased Caveolin-1 binding, decreased biological activity, and normal RhoGAP activity [13], we examined the ability of the colorectal cancer-associated DLC1-START mutants to bind Caveolin-1.