DNA-PKcs介导多药耐药恶性胶质瘤细胞化疗抗性及分子机制  

Chemoresistance of multi-drug resistance malignant glioma cells mediated by DNA-PKcs and its molecular mechanism

作　　者：惠双[1] 郭宏强[1] 

机构地区：[1]河南省南阳市中心医院肿瘤内科,河南南阳473009

出　　处：《吉林大学学报（医学版）》2016年第5期877-881,共5页Journal of Jilin University：Medicine Edition

基　　金：国家自然科学基金资助课题(81101797)

摘　　要：目的:观察DNA依赖的蛋白激酶的催化亚单位(DNA-PKcs)对多药耐药的恶性胶质瘤细胞化疗抗性的影响,探讨其介导化疗抗性的分子机制。方法:采用siRNA技术构建DNA-PKcs基因表达沉默的人胶质瘤U251细胞株;采用Western blotting法检测U251细胞(U251细胞)、多柔比星(ADM)耐药的U251细胞(U251/ADM细胞)和DNA-PKcs基因表达沉默的多柔比星耐药的U251细胞(U251/ADM/siDNA-PKcs细胞)中DNA-PKcs蛋白表达水平;采用CCK8法检测3组细胞增殖活性;采用Western blotting法检测3组细胞中多药耐药性1(MDR1)、报告基因质粒pNF-κB/p6、总Akt蛋白、pAkt/T308和pAKT/S473蛋白表达水平。结果:U251/ADM细胞DNA-PKcs蛋白表达水平明显高于U251细胞和U251/ADM/siDNA-PKcs细胞(P<0.01);ADM、紫杉醇(PTX)和吉西他滨(GEM)对U251/ADM/siDNA-PKcs细胞的半数抑制浓度(IC50)值较U251/ADM细胞明显降低(P<0.01);U251/ADM/SIDNA-PKcs细胞中pAKT/S473、pNF-κB/p65和MDR1蛋白表达水平均明显低于U251/ADM细胞(P<0.05),而两者总Akt和pAkt/T308蛋白表达水平比较差异无统计学意义(P>0.05)。结论:DNA-PKcs能明显增强多重耐药的恶性胶质瘤细胞化疗抗性,其作用机制与pAKT/S473和pNF-κB/p65表达上调,诱导MDR1表达有关。Objective：To obesrve the influence of DNA-PKcs in the chemoresistance of multi-drug resistance malignant glioma cells,and to explore its molecuIar mechanism in chemoresistance.Methods：siRNA was used to construct the DNA-PKcs knockdown human glioma U251 cell line;Western blotting method was used to detect the expressions of DNA-PKcs in U251 cells （U251 cells）, doxorubicin （ADM）resistant U251 cells （U251/ADM cells）,DNA-PKcs knockdown and ADM resistant U251 cells （U251/ADM/siDNA-PKcs cells）.CCK8 method was used to detect the cell proliferation activity in three groups;Western blotting method was used to detect the expressions of MDR1, pNF-κB/p6, total Akt, pAkt/T308 and pAKT/S473 in the cells in three groups. Results：The expression level of DNA-PKcs in U251/ADM cells was significantly higher than those in U251 cells and U251/ADM/siDNA-PKcs cells （P 〈 0.01 ）.The IC50 values of doxorubicin （ADM）,paclitaxel （PTX）, gemcitabine （GEM）in U251/ADM/siDNA-PKcs cells were significantly lower than that in U251/ADM cells （P 〈0.05）;the expression levels of pAKT/S473,pNF-κB/p65,and MDR1 in U251/ADM/siDNA-PKcs cells were significantly lower than those in U251/ADM cells （P 〈0.01）,but the total Akt and pAkt/T308 had no significant differences between two groups （P 〉0.05）.Conclusion：DNA-PKcs can significantly enhance the chemoresistance＆amp;nbsp;of multi-drug resistance malignant glioma cells,the underlying mechanism is related to up-regulation of pAKT/S473,pNF-κB/p65 and MDR1 expressions.

关 键 词：DNA依赖的蛋白激酶 胶质瘤 化疗抗性 多药耐药蛋白1 

分 类 号：R739.4[医药卫生—肿瘤]