乏氧诱导的自噬与肺腺癌放射抵抗的相关性研究  

Correlation between Hypoxia-induced Autophagy and Radioresistance of Lung Adenocarcinoma Cell Line A549

作　　者：邹燕梅[1] 熊华[1] 于世英[1] 袁响林[1] 

机构地区：[1]华中科技大学同济医学院附属同济医院肿瘤中心,武汉430030

出　　处：《华中科技大学学报（医学版）》2011年第4期413-416,共4页Acta Medicinae Universitatis Scientiae et Technologiae Huazhong

摘　　要：目的研究乏氧诱导的自噬与肺腺癌放射抵抗之间的相关性。方法肺腺癌A549细胞行常氧和乏氧培养。构建靶向抑制乏氧诱导因子-1α(HIF-1α)的shRNA表达质粒,转染乏氧A549细胞,筛选稳定表达的克隆细胞。克隆形成实验检测细胞放射敏感性。Western blot法检测各处理组细胞HIF-1α、beclin1蛋白的表达。结果乏氧细胞存活分数(SF2)为0.62,常氧细胞为0.43,提示乏氧A549细胞放射敏感性降低。常氧下A549细胞HIF-1α和beclin1蛋白低表达,乏氧12、24、48 h时间点HIF-1α和beclin1蛋白表达明显增加,差异均有统计学意义(P<0.05)。相应时间点HIF-1α与be-clin1的表达呈正相关(r=0.75,P<0.05)。A549/HIF-1α-shRNA的SF2为0.45,放射增益比(SER)为0.72,明显低于阴性对照组,说明抑制HIF-1α表达明显提高乏氧A549细胞放射敏感性。乏氧条件下HIF-1α的表达被抑制后beclin1蛋白的表达明显降低(24 h:t=5.69,P=0.01;48 h:t=5.13,P=0.01)。结论乏氧诱导的自噬参与肺腺癌的放射抵抗。Objective To study the correlation between hypoxia-induced autophagy and radioresistance of lung adenocarcinoma cell line A549.Methods A549 cells were cultured under normoxic or hypoxic condition.HIF-1α-siRNA expression plasmid（HIF-1α-shRNA/pGenesil-1）was constructed to get stable clone cells.Clone formation array was applied to calculate the radiosensitivity.The expression of HIF-1α and beclin1 was detected by using Western blot.Results A549 cells under hypoxia showed radio-resistance：its SF2 was 0.62,which was lower than the control cells（0.43）.Under normoxic condition,the expression of HIF-1α and beclin1 was low,but it was increased sharply at the time points of 12,24 h and 48 h of hypoxia（all P〈0.05）.There was significantly positive correlation between the expression of HIF-1α and beclin1（r=0.75,P〈0.05）.SF2 in positive clone cells was 0.45,and SER was 0.72,which were lower than the negative clone cells.It was suggested the inhibition of HIF-1α could raise the radiosensitivity.Under the hypoxic condition and after the inhibition of HIF-1α,the expression of beclin1 was significantly decreased（24 h：t=5.69,P=0.01;48 h：t=5.13,P=0.01）.Conclusion Hypoxia-induced autophagy is correlated with radioresistance of lung adenocarcinoma.

关 键 词：乏氧 自噬 放射敏感性 肺腺癌 

分 类 号：R734.2[医药卫生—肿瘤] R815[医药卫生—临床医学]