白血病细胞多药耐药与细胞凋亡的关系

STUDY OF RELATIONSHIP BETWEEN MULTIDRUG RESISTANCE AND APOPTOSIS IN LEUKEMIA CELL LINE K562

目的 :探讨白血病细胞多药耐药 (MDR)与细胞凋亡的关系。方法 :在体外用化疗药物阿霉素 (ADM)诱导白血病细胞株 K5 6 2 MDR的产生 ,用 As2 O3诱导细胞的凋亡 ,采用流式细胞仪检测细胞表面 P糖蛋白 (P- gp)的表达 ;荧光定量 PCR检测 MDR1 m RNA;通过流式细胞仪检测Anexin- V判断凋亡细胞数量的多少 ;观察 MDR与细胞凋亡的关系。结果 :5 μm ol/ L 的 ADM能诱导 K5 6 2细胞 MDR的产生 ,随着作用时间的延长 ,P- gp/ MDR1 m RNA的表达逐渐升高 ;P- gp/MDR1 m RNA的表达与细胞凋亡呈负相关 (r=0 .6 8,P<0 .0 1 ) ;在 As2 O3作用下 ,细胞凋亡增加的同时 ,P- gp的表达下调。结论 :抗癌药物能诱导白血病细胞 MDR的产生 ,细胞的耐药性与凋亡抑制相关 ,诱导细胞的凋亡能减低白血病细胞的 MDR。

Objective:To illustrate the relationship between multidrug resistance (MDR)and apoptosis in leukemia cell line K562.Methods:K562 cell MDR was gradually induced with ADM in vitro. Using flow cytometry(FCM) assay, the expression of P glycoprotein (P gp) was examined. The mRNA expressions of MDR was measured by fluorescent quantitative reverse transcriptase polymerase chain reaction(RT PCR).Apoptotic changes were observed by Anexin V.Results:After treatment with ADM 5 μmol/L for 24 h,48 h or 72 h, both MDR 1 mRNA and P gp began to rise,and reached highest level at 72 h. They were negatively correlated with the number of apoptosis K562 cells( r =0.68, P <0.01).The increase in apoptosis and decrease in P gp happened at same time when cells were treated with As 2O 3 for 72 h.Conclusion:MDR of K562 cells is closely related with suppresion of cell apoptosis. MDR can be reversed by inducing cell apoptosis.