17AAG-cypate聚合物胶束对肺癌A549细胞放射敏感性影响

Effect of 17AAG-cypate polymer micelle on radio-sensitivityof A549 cells

目的 研究17AAG-cypate胶束对人非小细胞肺癌A549细胞的放射增敏作用,并简析其可能机制。方法 单击多靶模型拟合实验方程分析17AAG-M和17AAG-cypate-M的放射增敏作用。MTT实验检测17AAG-cypate-M在激光和X射线照射下对A549细胞存活率的影响。β-半乳糖苷酶染色实验观察药物对细胞衰老产生的影响。γ-H2AX免疫荧光染色实验分析不同处理条件对DNA损伤修复的影响。蛋白印迹法实验检测p-Erk1/2和p-Akt蛋白的表达情况。配对t检验差异。结果 与单纯X射线照射组相比D0下降,SER〉1,说明17AAG-cypate-M具有放射增敏作用。与17AAG-M组相比,17AAG-cypate-M组对A549细胞活力抑制程度升高（P=0.0012）,且引发了更明显的DNA损伤修复延迟（P=0.0017）。同时,17AAG-cypate-M对p-Erk1/2和p-Akt表达水平的抑制程度高于17AAG-M。结论 与17AAG-M相比,17AAG-cypate-M对A549细胞的放射增敏作用更加明显,其放射增敏机制可能为引发细胞的衰老,延迟DNA损伤修复,抑制p-Erk1/2和p-Akt表达等。

Objective To investigate the radiosensitizing effect of 17AAG-cypate micelles on human non-small cell lung cancer A549 cells and its possible mechanism. Methods （1） A single-hit multi-target model formula was used to analyze the radiosensitizing effects of 17AAG-M and 17AAG-cypate-M.（2） The effects of 17AAG-cypate-M on the viability of A549 cells under laser and X-ray irradiation were analyzed by MTT assay.（3） The effect of the drugs on the cell senescence was observed by β-galactosidase staining assay.（4） The effects of different treatment conditions on DNA damage repair were analyzed by γ-H2AX immunofluorescence staining assay.（5） The expression of p-Erk1/2 and p-Akt was measured by Western blot. The paired t test was used for analyzing the differences between groups. Results Compared with the X-ray irradiation group, the X-ray＋17AAG-cypate-M group had a lower mean lethal dose and a sensitization enhancement ratio greater than 1, indicating that 17AAG-cypate-M had a radiosensitizing effect. Compared with the 17AAG-M group, the 17AAG-cypate-M group showed significantly lower cell viability （P〈0.01）, a significantly higher percentage of aging cells （P〈0.01）, and significantly further delayed DNA damage repair （P〈0.01）. And the 17AAG-cypate-M group had lower expression of p-Erk1/2 and p-Akt than the 17AAG-M group. Conclusions Compared with 17AAG-M, 17AAG-cypate-M has a higher radiosensitizing effect on A549 cells. The mechanism might be inducing the cell senescence, delaying DNA damage repair, and inhibiting the expression of p-Erk1/2 and p-Akt.