Previous studies have found that P-gp is overexpressed in resistant breast cancer, lung cancer and colon cancer cells [5,6,7], as well as in patients with neuroblastoma, acute myeloid leukemia, acute lymphoblastic leukemia [8,9,10,11] and many other cancers [12], indicating that it is an important target, the inhibitor of which is emerging as one promising approach to overcome MDR [13,14]. The gene discussed is PGP; the disease is cancer.