不同浓度七氟醚对人脑胶质瘤细胞U251替莫唑胺抵抗的影响及机制初探

摘要

目的 探究不同浓度七氟醚对人脑胶质瘤细胞U251替莫唑胺(TMZ)抵抗的影响,并探讨其可能的作用机制.方法 培养对数生长期的人脑胶质瘤细胞U251,传代后将细胞分为3组:对照组、低七氟醚组及高七氟醚组.对照组在5%CO2气体条件下培养,低七氟醚组在5%CO2+1%七氟醚气体条件下培养,高七氟醚组在5%CO2+2.5%七氟醚气体条件下培养,总气流量为2 L/min.MTT法检测3组细胞TMZ半抑制浓度(IC50)的变化,荧光定量链式聚合酶反应(qPCR)检测细胞缺氧诱导因子-1α(HIF-1α)mRNA表达水平的变化,蛋白免疫印迹(Western blotting)检测HIF-1α蛋白表达水平的变化.结果 MTT结果显示对照组细胞TMZ IC50值显著高于高七氟醚组IC50值(P<0.05),而与低七氟醚组IC50值差异无统计学意义(P>0.05).qPCR结果显示对照组HIF-1αmRNA相对表达水平显著高于低七氟醚组及高七氟醚组(P<0.05),且低七氟醚组HIF-1αmRNA相对表达水平显著高于高七氟醚组(P<0.05),Western blotting结果显示对照组HIF-1α蛋白表达水平明显高于低七氟醚组及高七氟醚组,且低七氟醚组HIF-1α蛋白表达水平明显高于高七氟醚组.结论 七氟醚促进人脑胶质瘤细胞U251对TMZ的敏感性,可能与下调HIF-1α有关.%Objective To investigate the effect of different concentrations of sevoflurane on the resistance of human glioma cell U251 to temozolomide ( TMZ) and explore the possible mechanism. Methods Human glioma cell U251 in logarithmic growth phase was cultured and divided into 3 groups: the control group, low sevoflurane group and high sevoflurane group. The control group was cultured under the gas condition of 5%CO2, and the low sevoflurane group was cultured under the gas condition of 5% CO2+ 2.5% sevoflurane, and the high sevoflurane group was cultured under the gas condition of 5%CO2+ 5%sevoflurane. The total gas flow rate was 2 L/min. MTT method was used to detect the half inhibitory concentration ( IC50 ) to TMZ. Fluorescence quantitative polymerase chain reaction ( qPCR) was used to detect the mRNA expression of hypoxia inducible factor-1α ( HIF-1α) . Western blotting was used to detect the protein level of HIF-1α. Results The TMZ IC50 value in the control group were significantly higher than that in the high sevoflurane group ( P<0.05) , but there was no significant difference between the control group and the low sevoflurane group ( P>0.05) . The levels of HIF-1α mRNA and protein in the control group were significantly higher than that in two sevoflurane groups, in which HIF-1αlevel in the low sevoflurane group was higher than that in the high sevoflurane group. Conclusion Sevoflurane can increase the sensitivity of glioma cell line U251to TMZ via down-regulating the expression of HIF-1α.