ABSTRACT
AIM: To study the effect of CPUE1 on the reversal of multidrug resistance (MDR) in K562/A02 cells and its mechanism. METHODS: MTT assay was used to determine the influence of CPUE1 on the cytotoxicity of vincrisine (VCR) in K562/A02 cells. The effect of CPUE1 on the apoptosis induced by VCR in K562/A02 cells was detected using DNA analysis and Annexin-Ⅴ/PI double stain assay. Flow cytometry was used to investigate the efflux of rhodamine123 (Rh123) by P-glycoprotein (P-gp) in K562/A02 cells. RESULTS: CPUE1 increased the cytotoxicity and apoptosis induced by VCR in K562/A02 cells. At the concentration of 10 ?mol?L -1 ,CPUE1 reduced the IC_ 50 value of VCR from 60.54 to 4.17 ?mol?L -1 . CPUE1 inhibited the efflux of Rh123 and resulted in the increase of intracellular accumulation of Rh123 in K562/A02 cells. CONCLUSION: CPUE1 has strong reversal effect on MDR in K562/A02 cells by inhibiting P-gp activity.