FIGURE 5.

Combined effects of acriflavine (ACF) and imatinib (IM) on sensitive and resistant K562 cells. A, K562S cells were treated with different concentrations of ACF and IM for 72 h, and the percentages of viable cells were determined by MTT assays. Isobologram analysis was established according to values obtained with combined drugs in dose‐response experiments. B, K562S and K562R cells cultured, without and with 1 μmol/L IM, respectively, were treated with increasing concentrations of ACF for 72 h, and the percentages of viable cells were determined by MTT assays (data are presented as mean ± SD of four independent experiments done in triplicates). C, Protein extracts from K562S and K562R cells treated with ACF and/or IM for 72 h were analysed by western blot to detect the phosphorylation and expression of BCR‐ABL. D, The phosphorylation and expression of STAT3/5A/5B in K562R cells treated or not with ACF (2 μmol/L) were also determined by immunoblotting. C and D, Actin served as the loading control