Among them, ABCB1 (P-glycoprotein; P-gp, MDR1), ABCC1 (multidrug resistance-associated protein 1; MRP1), and ABCG2 (breast cancer resistance protein; BCRP, mitoxantrone resistance protein; MXR) are the major transporters involved in MDR, in cancer cells. This evidence concerns the gene ABCC1 and cancer.