In summary, cetuximab could enhance the cytotoxicity of conventional anticancer agent in ABCB1-overexpressing cancer cells by decreasing fluidity of MDR cell membrane and inhibiting the drug transport function and increasing intracellular accumulation of chemotherapeutic agent, but not involving in alteration of ABCB1 expression and the blockade of AKT and ERK signal transduction pathways in EGFR expression MDR cells. This evidence concerns the gene AKT1 and cancer.