uPAR衍生RERF肽逆转K562/ADM耐药及其机制

摘要

目的 采用新合成的尿激酶型纤溶酶原激活物受体(uPAR)衍生肽(RERF肽),探讨其对白血病耐药细胞K562/ADM耐药性的逆转作用及其机制.方法 应用MTT法观察RERF肽对K562/ADM细胞生长增殖影响及非细胞毒素剂量对耐药逆转作用.应用实时荧光定量PCR (qPCR)检测RERF肽作用后K562/ADM细胞中uPA、uPAR和MDR1基因的表达;Western blot检测RERF肽作用后K562/ADM细胞中uPA、uPAR和P-gp蛋白的表达.结果 ADM单独作用K562/ADM细胞24、48、72 h,IC50分别为92.48±0.27、30.99±0.19、28.06±0.12tg/mL;ADM与非细胞毒性剂量的RERF肽共同作用K562/ADM细胞24、48、72 h,IC50分别降低为83.83±0.29、18.52±0.17、16.38±0.13 μg/mL.联合用药48 h后K562/ADM细胞其uPA、uPAR、MDRl mRNA与uPA、uPAR和p-gP蛋白的表达量明显降低(P＜0.05).结论 RERF肽可部分逆转K562/ADM细胞对ADM的耐药性,提高ADM的敏感性.RERF肽有可能通过uPA/uPAR途径下调MDR1基因,降低P-gp的表达,从而逆转白血病耐药.%Objective To investigate its effect of the newly synthesized uPAR-derived peptide (RERF peptide) on leukemic K562/ADM and its mechanism.Methods The effect of RERF peptide on the proliferation of K562/ADM cells was observed by MTT assay.The reversal effect of non-cytotoxic dose of RERF peptide on drug resistance of adriamycin resistant K562/ADM cells was observed.The relative expression of uPA,uPAR and MDR1 gene in K562/ADM cells was detected by qPCR.And the expression of uPA,uPAR and P-gp protein in K562/ADM cells were detected by a western blot analysis.Results The IC50 values of K562/ADM cells were 92.48±0.27,30.99±0.19,28.06±0.12 μg/mL respectively at 24 h,48 h,and 72 h after ADM administration.The IC50 decreased to 83.83±0.29,18.52±0.17,16.38±0.13 μg/mL respectively at 24 h,48 h and 72 h after ADM combined with non-cytotoxic doses of RERF peptide.The expression of uPA,uPAR,MDR1 mRNA and p-gp protein in K562/ADM cells after treatment 48 h were significantly decreased (P ＜ 0.05).Conclusion RERF peptide could partially reverse the drug resistance of ADM in K562/ADM cells and improve the sensitivity of ADM.RERF peptide could reverse the resistance by affecting MDR1 gene via the uPA/uPAR pathway and decrease the express of P-gp.