KRAS and neoplasm: It blocks microspike formation in 3T3 fibroblast cultures, neuronal branching, and actin-based motility and migration in PC-3 cells.340 Another ZCL compound, ZCL367, binds to CDC42 with improved selectivity and inhibits proliferation and migration of multiple tumor cell lines, including the lung cancer cells containing EGFR or KRAS G12S mutations.341 CASIN (CDC42 activity-specific inhibitor) is another ligand that interferes with GEF-mediated activation.