It is an important member of the ATP-binding cassette (ABC) transporters.[5,6] Several studies have demonstrated the possibility of using P-gp inhibitors to reverse the P-gp mediated efflux MDR in an attempt to improve the efficiency of chemotherapeutic agents as well as the pharmacokinetic and pharmacodynamic profiles of a number of challenging molecules, especially potent cancer curing compounds. This evidence concerns the gene PGP and cancer.