CDC42 and breast cancer: Other studies on ERα-negative MDA-MB 231 basal-like breast cancer (BLBC) cells have shown that Cdc42 can inhibit the ability of c-Cbl to promote degradation of one of its target proteins, the receptor for epidermal growth factor [EGFR, which is overexpressed in many BLBCs (Hirsch et al, 2006)].