Figure 5.

Ubenimex decreases the expression of P-gp and MRP1 by inhibiting CD13 expression to alleviate the activation of PI3K/AKT/mTOR pathway. ((a) and (b)) Indicted cells were pretreated with pEGFP-N1-CD13 plasmid and then stimulated with Ubenimex. Expressions of total and phospho-proteins related to PI3K/AKT pathway in SGC7901/X (a) and MKN45/X (b) cells were identified by western blotting analysis. Data are shown as representatives (left panels) or means ±SD from three independent experiments (right panels).  ^∗∗P<0.01 and  ^#P>0.05. ((c) and (d)) Coimmunoprecipitation of endogenous mTOR and P-gp or MRP1 in indicated MDR GC cells with the treatment of Ubenimex (400μmol/l) for 24h. Total cell lysates were used as an input control and were subjected to immunoprecipitation and western blotting analysis with the indicated antibodies.