Fig 1: Expression of the ABCB1, ABCC1, ABCG2 genes and P-gp, MRP1, BCRP proteins in BJAB/ADR cells. (A) The expression of the ABCB1 gene in the ADR-resistant BJAB/ADR cells. The mRNA level of MDR1 analyzed by qRT-PCR and normalized to the mRNA level of the housekeeping gene GAPDH. Compared with the sensitive cells BJAB, BJAB/ADR drug-resistant cells showed increased expression of ABCB1 mRNA. *P < 0.05, compared with control group. (B) The protein expression of P-gp on BJAB/ADR cells. The expression of P-gp was evaluated via flow cytometry analysis. BJAB/ADR cells showed higher expression of the membrane protein P-gp compared with the BJAB sensitive cells. (C,E) The qRT-PCR on the gene expression of ABCC1 and ABCG2, respectively. These results showed higher expression levels of both genes, but the increased expression was not as high as that of ABCB1. *P < 0.05, compared with control group. (D,F) The protein expression level of MRP1 and BCRP, separately. The results were obtained from flow cytometry analysis. These results indicated that higher expression levels of both protein, but the increased expression was not as high as that of P-gp.