多西紫杉醇对非小细胞肺癌细胞株A-549放疗增敏作用及机制

目的：研究多西紫杉醇对体外培养非小细胞肺癌细胞的细胞周期改变和凋亡影响,及其放疗增敏的作用及机制。方法：以非小细胞肺癌细胞株A-549为实验对象,MTT法观察多西紫杉醇对A-549细胞增殖抑制;克隆形成实验分析细胞放射敏感性;流式细胞技术检测细胞周期及凋亡率。结果：多西紫杉醇对A-549细胞有生长抑制作用,且呈剂量依赖性,在较低浓度（1μg/ml）时即可降低A-549细胞的克隆形成率。各处理组细胞的细胞周期和凋亡率结果表明,多西紫杉醇＋放疗组G2/M期细胞比例较其他组明显升高,差异有统计学意义（P〈0.05）;细胞凋亡率差异亦有统计学意义（P〈0.05）。结论：多西紫杉醇在低细胞毒性浓度下对非小细胞肺癌细胞株A-549有放射增敏作用;多西紫杉醇对A-549细胞增敏其机制可能与其能改变细胞生长周期并诱导其凋亡有关。

Radiosensitization of Docetaxel on non-small cell lung cancer A-549 cell line and its mechanism

Objective：To study the growt hinhibition and radiosensitivity effect of Docetaxel on non-small cell lung cancer A-549 cell line.Methods：MTT assay was used to test the inhibitory effect of Docetaxel on the NSCLC A-549 cell line proliferation and clonogenic assay was performed to determine the radiosensitization effect of Docetaxel on A-549 cell line.Change of cell cycle and apoptosis was detected by flowcytometry.Results：Docetaxel inhibited A-549 cell line proliferation in a dose-dependent manner.A low-cytotoxic concentration of Docetaxel at 1 μg/ml significantly reduced the cloning efficiency of A-549 cell line.Apoptosis rates and G2/M phase cell proportion in the radiation group was significantly higher in the Docetaxel ＋ radiation group compared with the other group （P0.05）.Conclusion：There was effect of radiosensitivity of A-549 cell line exposed to low-cytotoxic concentrations;the mechanism may be related with Docetaxel induced apoptosis and modified cell cycle in non-small cell lung cancer A-549 cell line.