A549细胞线粒体DNA缺失模型建立及其放射敏感性变化  

Establishment of mitochondriai DNA depleted A549 cell line and the change of its radiosensitivity

作　　者：何为[1,2] 周福祥[1] 徐会[1] 江换钢[1] 胡柳[1] 谢丛华[1] 周云峰[1] 

机构地区：[1]湖北省肿瘤生物学行为重点实验室湖北省肿瘤医学临床研究中心武汉大学中南医院放化疗科,武汉430071 [2]湖北省中山医院

出　　处：《中华放射医学与防护杂志》2014年第4期255-258,共4页Chinese Journal of Radiological Medicine and Protection

基　　金：国家自然科学基金（81172129）

摘　　要：目的建立肺癌A549细胞线粒体DNA（mtDNA）缺失模型（p°细胞），观察其放射敏感性变化。方法用含微量溴化乙锭（EB）的特殊培养液持续培养正常的A549细胞（p°细胞）以获得mtDNA完全缺失的p°细胞，利用生长缺陷及PCR鉴定该细胞模型。利用克隆形成实验分别检测两种细胞的放射敏感性，利用碘化丙啶（PI）染色法及二氯荧光素双醋酸盐（DCFH．DA）染色法，分析两种细胞在6MVX射线照射后的细胞周期及活性氧簇（ROS）变化情况。结果成功建立A549P”细胞。p°细胞较p°细胞放射敏感性降低（t=12．57，P〈0．01）。放射照射8Gy后，p°细胞较p°细胞G：期阻滞时间延长，G：期细胞比例降低（t=6．82，P〈0．01），p°细胞ROS升高水平明显低于p°细胞（t=14．51，P〈0．01）。结论p°细胞较p‘细胞放射敏感性降低，其机制可能与放射照射后ROS产量降低及G2期阻滞延长有关。Objective To establish the mitochondrial DNA depleted cell line （pO cells） of lung cancer cell A549 and to observe the radiosensitivity difference between p° cells and normal A549 cells （ p°cells）. Methods The pO cells were depleted of mitochondrial DNA by culturing chronically in the presence of low concentration of ethidium bromide （EB）, and then the cell model was confined. Radiosensitivity of both pO cells and p ~ cells was detected using the cologenic formation assay. After 6 MV X-ray irradiation in vitro, cell cycle distribution and reactive oxygen species （ROS） level were analyzed by flow cytometry and fluorescence microplate reader, respectively. Results A p0 cell line was successfully established and had a lower radiosensitivity thanp° cells （ t = 12.57, P 〈 0.01 ）. After irradiation with a dose of 8 Gy, compared to p°cells, pO cells showed prolonged G2 arrest with less cells in G2 （t = 6.82, P〈0. 01） and had lower increase of ROS level （t = 14.51, P 〈0.01）. Conclusions pO cells have a lower radiosensitivity than p°cells, in which the reduction of ROS production and the prolongation of G2 arrest post-irradiation may be involved.

关 键 词：线粒体DNA缺失p°细胞 MTDNA A549 放射敏感性 

分 类 号：R734.2[医药卫生—肿瘤]