PGP and cancer: On the other hand, we observed that the IC50 values of ensartinib for P-gp-overexpressing cancer cell lines, regardless of the tissue of origin, and HEK293 cells with ectopic expression of P-gp were significantly higher than the IC50 values in the respective drug-sensitive parental cells, which could be reversed by the P-gp inhibitor tariquidar (Table 1).