γ射线照后不同时间点人肝细胞基因差异表达谱的研究

Differential gene expression profile in human hepatocytes irradiated by γ-rays after different time points

目的:对γ射线照射后4和24 h人肝细胞株的差异表达基因进行筛选,为从基因水平上揭示放射性从业人员肝脏的早期损伤提供依据。方法:利用全基因组基因芯片技术,对人正常肝细胞7702给予不同剂量(0.5和1.0 Gy)γ射线照射不同时间(4和24 h)后的基因差异表达谱进行筛选和分析。结果:照后4 h在不同剂量水平上(0.5和1.0 Gy)筛选出差异表达基因218个;照后24 h不同剂量水平上(0.5和1.0 Gy)筛选出差异表达基因1 475个;0.5 Gy剂量水平上照后不同时间(4和24 h)筛选出差异表达基因235个;1.0 Gy剂量水平上照后不同时间(4和24 h)筛选差异表达基因170个;最后筛选出共同的差异表达基因129个;另外还发现了一些有意义的通路途径,如胰岛素合成与分泌途径等;同时为了验证基因芯片筛选结果的准确性,进一步采用SYBR绿色实时荧光定量PCR技术,对胰岛素生长因子2结合蛋白3(IGF2BP3)及早期响应因子1(EGR1)两个有意义且表达量稳定的辐射后差异表达基因进行了验证,结果显示其定量结果与芯片检测结果趋势一致。结论:γ射线辐照后共筛选出差异表达基因129个,辐射对人肝细胞的早期损伤表现为多靶点、多层次及多通路等特点。

OBJECTIVE：To provide gene-level evidence for hepatic early damage of staff exposed to irradiation.METHODS：The study analyzed the differential gene experession profile of normal human hepatocytes and human hepatocytes irradiated at 2 different doses（0.5 and 1.0 Gyγ-rays） using whole genome chip after4 and 24 h. RESULTS：There were 218 differentially expressed genes irradiated with 2 doses after 4 h,and there were 1 475 differentially expressed genes irradiated with 2 doses after 24 h.There were 235 differentially expressed genes irradiated with 0.5 Gy in 2 time-points.There were 170 differentially expressed genes irradiated with 1.0 Gy in 2 time points.There were 129 differentially expressed genes irradiated with 0.5 Gy and 1.0 Gy at 4 h and 24 h.Some interesting pathways such as insulin synthesis and secretion were found.The quantities of IGF2BP3 and EGR1 mRNA analyzed with real-time PCR were consisitent with gene chip.CONCLUSION：There were 129 differentially expressed genes identified.Irradiation caused early damage to human hepatocytes at many targets,many levels and through many pathways.