PGP and cancer: Various nanocarriers have been developed for the co-delivery of anti-cancer drugs and P-gp inhibitors, such as the co-delivery of paclitaxel and borneol in lipid-albumin nanocomplex [29,30,31], docetaxel and verapamil in polymeric micelles [32], and paclitaxel and curcumin in lipid-albumin hybrid nanoparticles [33].