摘要： 目的 观察高级别胶质瘤细胞系（U87、U251 和LN229）γH2AX 蛋白表达变化，据此判断胶质瘤对放射线的敏感程度。方法 选择胶质瘤细胞系U87、U251和LN229细胞株，通过细胞克隆形成实验，检测经不同剂量（0、2、4、6、8 和10 Gy）X 线照射后胶质瘤细胞克隆形成率，并绘制细胞存活曲线、测定放射敏感性；采用Western blotting 法检测经剂量为2 Gy 的X 线照射后不同时间点（0 min、30 min、1 h、2 h、6 h、12 h、24 h、36 h 和48 h）各胶质瘤细胞系γH2AX 蛋白表达变化。结果 细胞克隆形成实验显示，随着X 线照射剂量的增加，胶质瘤细胞存活分数逐渐降低、细胞克隆形成率减少，放射增敏比自高至低依次为U87、LN229和U251细胞（均P = 0.000）。Western blotting法显示，随着X 线照射时间的延长，各胶质瘤细胞系γH2AX 蛋白表达呈现先上升后下降的时间效应曲线，U87、LN229 和U251 细胞γH2AX 蛋白表达峰值时间依次为2、1 和1 h（P = 0.000、0.000、0.015）；γH2AX 蛋白相对衰减速度（r = 0.733，P = 0.025）和升高程度（r = 0.672，P = 0.047）均与放射增敏比呈正相关。结论 γH2AX 蛋白有望成为检测高级别胶质瘤细胞系放射敏感性的一项预测指标。
关键词:
神经胶质瘤,
细胞系, 肿瘤,
辐射耐受性,
DNA 损伤,
细胞, 培养的
Abstract: Objective To observe the expression changes of γH2AX in high-grade glioma cell lines (U87, U251 and LN229) and to investigate the relationship between the expression of γ H2AX and the radiosensitivity of high-grade glioma cells in vitro. Methods The radiosensitivity of glioma U251, U87 and LN229 cell lines were measured by clone forming assay. Afte X-ray irradiation of different doses (0, 2, 4, 6, 8 and 10 Gy), the clone forming rates of 3 cell lines were measured, and cell survival curves were drawn. The DNA double-strand break (DSB) damage of 3 cell lines were determined by Western blotting assay. Results For glioma U251, U87 and LN229 cell lines, the survival fraction and clone forming rate were gradually decreased with the increase of Χ-ray radiation dose, and the radiotherapy sensitization enhancement ratio (SER) of U87 cells was slightly higher compared with LN229, U251 cells (P = 0.000, for all). In the Western blotting assay, the kinetics of the expression of γH2AX protein after irradiation was featured by increase and decay. The γH2AX expression of U87, LN229 and U251 cells after irradiation reached the peak value at 2 h, 1 h and 1 h respectively (P = 0.000, 0.000, 0.015). There was positive correlation between SER and γH2AX attenuation speed (r = 0.733, P = 0.025), as well as between SER and degree of increasing (r = 0.672, P = 0.047). Conclusions The phosphorylated histone γH2AX is expected to become a powerful tool to monitor DNA DSB and to predict the radiosensitivity in high-grade glioma nradiotherapy.
Key words:
Glioma,
Cell line, tumor,
Radiation tolerance,
DNA damage,
Cells, cultured
王均伟, 张春智, 韩宝林, 王雷波, 姚鑫. γH2AX 对胶质瘤放射敏感性预测效果的实验研究[J]. 中国现代神经疾病杂志, 2014, 14(3): 240-244.
WANG Jun-wei, ZHANG Chun-zhi, HAN Bao-lin, WANG Lei-bo, YAO Xin. Predictive effect of γH2AX expression on the radiosensitivity of glioma[J]. Chinese Journal of Contemporary Neurology and Neurosurgery, 2014, 14(3): 240-244.