The phenomenon of multidrug resistance is a common cause of failure of cancer chemotherapy. Tested a number of cellular mechanisms that affect the cytotoxic effects of anticancer drugs. One of the most intensively studied forms of cell resistance to therapy resistance is caused by overexpression of membrane glycoproteins. Some membrane proteins responsible for membrane transport of drugs and genes encoding them have been identified and characterized. They play an important role in reducing the intracellular levels of drugs.