Efflux Transporters In Anti-Cancer Drug Resistance: Molecular And Functional Identification And Characterization Of Multidrug Resistance Proteins (Mrps/Abccs)

Nine members of the ATP-binding cassette (ABC) transporter subfamily C are often referred to as "multidrug resistance proteins" due to the ability of some of these proteins to confer resistance to anti-cancer drugs. The founding member of this sub-family, MRP1/ABCC1, is the major focus of this chapter, because to date, it is the only ABC subfamily C member with a widely accepted role in clinical anti-cancer drug resistance. Evidence is accumulating that multiple ABC subfamily C members contribute to poor cancer patient prognosis through drug export-independent functions. These roles are also discussed, with amajor focus on ABCC1 and ABCC4.