自噬在不同分割方案放疗联合化疗中对肺癌细胞的杀伤作用及其机制  

Killing effects of autophagy on lung cancer cells in different kinds of radiotherapy methods combined with chemotherapy and related mechanisms

作　　者：李菁菁[1] 刘明博[1] 侯雨菲 徐珊[1] 孔德娟[1] 梁冰[1] 贺梦子[1] 梁楠[1] 马淑梅[1] 刘晓冬[1] 

机构地区：[1]吉林大学公共卫生学院卫生部放射生物学重点实验室,吉林长春130021

出　　处：《吉林大学学报（医学版）》2013年第6期1098-1102,1311,共6页Journal of Jilin University：Medicine Edition

基　　金：国家自然科学基金资助课题(30770649;30970682);国家大学生创新项目资助课题(2012A72202)

摘　　要：目的:通过离体实验、在体实验观察不同放疗方案以及顺铂增敏放疗对肺癌细胞的杀伤效应,探讨自噬在这一过程中发挥的作用及其机制。方法:采用人肺癌细胞A549,以不同浓度(0、1.0、2.5、5.0、10.0、20.0和40.0μmol·L-1)顺铂进行处理;40只C57BL/6小鼠随机分为对照组(n=10)、常规分割照射组(n=10)、超分割照射组(n=10)和联合组(n=10),建立C57BL/6小鼠肺癌异位移植模型。MTT法检测A549细胞存活率,Western blotting法检测各组小鼠自噬相关基因MAPLC3和Beclin1蛋白的表达。采用游标卡尺测量各组小鼠肿瘤体积;免疫组织化学法检测肿瘤组织中自噬相关基因MAPLC3Ⅱ、PI3KⅢ和Beclin1的表达水平。结果:顺铂药物浓度>5.0μmol·L-1时A549细胞的存活率呈剂量依赖性下降;与对照组(0μmol·L-1顺铂)比较,10.0、20.0和40.0μmol·L-1顺铂组细胞存活率降低(P<0.05)。与对照组比较,其他各组小鼠自噬相关基因MAPLC3Ⅱ和Beclin1蛋白表达水平明显升高;超分割照射组小鼠肿瘤体积<联合组<常规分割照射组<对照组;与对照组比较,其他各组肿瘤体积均减小(P<0.05)。肿瘤组织切片染色,与对照组比较,其他各组自噬相关基因MAPLC3Ⅱ、PI3K-Ⅲ和Beclin1表达水平均明显升高(P<0.05),且在联合组达到最高值。结论:顺铂协同增敏放疗对肺癌细胞的杀伤作用,自噬可能参与其调控。Objective To observe the killing effects of different kinds of radiotherapy methods and the radiosensitization of cisplatin on lung cancer cells and to explore the role of autophagy and related mechanisms by in vitro and in vivo experiments. Methods Lung cancer cells A549 were treated with different concentrations （0, 1.0, 2.5, 5.0, 10.0, 20.0, and 40.0 μmol·L^-1） of cisplatin. 40 C5？BL/6 mice were randomly divided into control group （n= 10）, conventional fractionated radiation group （n= 10）, hyperfractionated radiation group （n= 10）, and combination group （n= 10）. The tumor-bearing C5？BL/6 models were established. MTT assay was used to detect the cell viability; Western blotting method was used to detect the expressions of autoiphagy-relative gene MAPLC3 and Beclinl protein of the mice in various groups; the tumor volumes of the mice were mesured by caliper; the expression levels of MAPLC3 II, PI3K III, and Beclinl in tumor tissue were detected by immunohistochemistry. Results With the increasing of eisplatin concentration （〉5 μmol·L^-1）, the cell viability of A549 cells was decreased significantly; the cell viabilities in 10.0, 20.0, and 40.0μmol·L^-1 eisplatin groups were decreased compared with control group （0 μmol·L^-1 cisplatin） （P〈0.05）. Compared with control group, the expression levels of MAPLC3 II and Beclinl in A549 cells in the other groups were increased. The tumor volumes were compared, hyperfractionated radiation group combinatin group~ conventional fractionated radiation group. control group. Compared with control group, the tumor volumes of the mice in the other groups were decreased （P〈0.05）. Compared with control group, the expression levels of MAPLC3 II , PI3K III, and Beclinl in the other groups were increased significantly （ P 〈 0.05 ）, especially in combination group. Conclusion The synergistic cytotoxic effect of ciaplatin with irradiation results in a killing effects on lung cancer cells, and autophagy might participate in this

关 键 词：自噬 顺铂 放疗 肺肿瘤 移植瘤 

分 类 号：R73[医药卫生—肿瘤]