ABCC1 and neoplasm: Another emerging form of taxane resistance is the increased expression of multidrug resitance (MDR) proteins – efflux pumps that remove cancer drugs from the tumor cell cytoplasm – such as the ATP Binding Cassette Subfamily B Member 1 (ABCB1 protein), P-glycoprotein and the Multidrug resistance-associated protein 1 (MRP1) 58,59.