The mechanisms of MDR include ATP-binding cassette (ABC) transporter proteins, bcl-2 family, survivin family, anti-oxidants, DNA repair activity etc. For example, multidrug resistance protein 1 (MDR1/P-glycoprotein/ABCB1) and multidrug resistance-related protein 1 (MRP1/ABCC1), both belonging to the ABC super family of membrane-bound transporters, are two genes that are found to be highly related to multidrug resistance of leukemia cells. The gene discussed is ABCB1; the disease is leukemia.