中文摘要：

目的：获得稳定的非小细胞肺癌（NSCLC）放射抗拒细胞系，明确常规分割和大分割放疗后肿瘤基因表达改变。方法：采用A549细胞系，6MV X线常规照射（2 Gy×17 f）和大分割照射（4 Gy×7 f），克隆形成实验和γ-H2AX免疫荧光染色结合共聚焦显微镜验证细胞的放射抗拒特性。提取mRNA，全基因组表达谱芯片检测差异基因表达，分析2倍以上改变的基因（P〈0.05），同时对芯片结果行Pathway分析（Q〈0.05）。结果：获得了2株放疗抗拒细胞系A549R2Gy-R和A549R4Gy-R。表达谱芯片显示，A549与A549R2Gy-R相比，差异表达基因为1701个（357个上调，1344个下调）；A549与A549R4Gy-R相比，944个基因上调，2602个基因下调。A549R2Gy-R与A549R4Gy-R相比，318个基因上调，699个基因下调。常规分割照射与大分割照射的pathway显著性富集分析显示，PI3K和Erb B通路等多条信号通路激酶出现显著性差异。结论：多种基因和信号通路参与了NSCLC常规分割和大分割放疗抗拒过程，进一步研究能明确NSCLC放射抗拒机制和为放疗增敏药物开发提供新靶点。

英文摘要：

Objective：To obtain stable radioresistant non-small-cell lung cancer （NSCLC） cell lines and identify the genetic pattern of conventional fractioned and hypofractionated radiotherapy. Methods：A549 NSCLC cells were treated with 6 MV of x-rays through conventional fractionated （2 Gy, 17 f） and hypofractionated irradiation （4 Gy, 7 f） to establish a radiation resistance cell model. Tumor cell radioresistance was determined using a clonogenic assay andγ-H2AX immunofluorescence staining combined with confocal microscopy. After extracting total mRNA from the cells, a whole genome expression microarray was applied to detect differential gene expression. The genes with at least a twofold increase in expression （P〈0.05） were analyzed, and the pathway （Q〈0.05） methods were used to further analyze the chip results. Results：After irradiating the A549 cells, two radioresistant cell lines were obtained, namely, the A549R2Gy-R and the A549R4Gy-R cell lines. The A549R2Gy-R cell line was radioresistant to the conventional fractionated irradiation, whereas the A549R4Gy-R cell line was ra-dioresistant to hypofractionated irradiation. Microarray analysis showed that the A549R2Gy-R cells exhibited 1 701 differentially expressed genes （357 upregulated, 1 344 downregulated） compared with the parental A549 cell. By contrast, the hypofractionated irradiation-resistant A549R4Gy-R cells had 944 upregulated genes and 2 602 downregulated genes compared with the A549 cells. The A549R2Gy-R cells exhibited 318 upregulated genes and 699 downregulated genes compared with the A549R4Gy-R cells. Several signaling pathways were implicated in radioresistance when conventional fractionated radiotherapy was compared with hypofractionated irradiation radiotherapy using path way-significant enrichment analysis, especially the PI3K and Erb B channel signaling pathway kinase. Conclusion：Multiple genes and signaling pathways are involved in the development of radiation resistance in NSCLC. The underlined radioresistance me