Figure 6 Asiaticoside antagonized P-gp-mediated MDR in HCC cells by decreasing the expression level of P-gp through decreasing the intracellular ROS level. The colored bar plot shows the IC50 values of doxorubicin (A), paclitaxel (B), colchicine (C), and vincristine (D) after treatment with indicated concentrations of asiaticoside in parental Bel-7402 cells as well as chemoresistance of Bel-7402/ADM cells. Western blot assays showed the inhibitory effect of asiaticoside on P-gp protein expression (E), and relative intensity of P-gp after treatment with asiaticoside in Bel-7402/ADM cells is shown in (F). The intracellular ROS level in Bel-7402/ADM cells after treatment with asiaticoside for 48 h (G). Data are presented as mean±SD, which are representative of at least 3 independent experiments.