辐射诱导Egr-1调控腺病毒介导Trail基因体外表达及意义

Expression property of Ad-Egr-hTrail induced by ionizing radiation

目的探讨不同辐射剂量X射线照射对转染重组腺病毒（Ad-Egr-hTrail）的胶质瘤U251细胞hTrailmRNA表达的影响。方法扩增Ad-Egr-hTrail。将扩增鉴定成功的Ad-Egr-hTrail感染U251细胞,感染48 h后分别予0、2、5、8、10、12、15、18 Gy X射线照射,real-time quanitative-PCR法测定不同剂量照射后肿瘤细胞中Trail mRNA表达。结果 U251细胞TrailmRNA表达水平照射后1 h开始升高,4~8 h维持在较高表达水平,照射后4 h表达水平最高,随后开始下降;随照射剂量增加,Trail mRNA表达水平明显增加,12 Gy时达到最高水平,然后随照射剂量增加,表达水平开始下降。结论重组腺病毒经射线诱导Egr-1基因启动子能够调控Trail基因体外表达,Trail基因表达量与放射剂量及放射后间隔时间有关。

Objective To investigate the effects of different doses of X-ray radiation on the expression of hTrail mRNA of glioma U251 cells which transfected Ad-Egr-hTrail.Methods Ad-Egr-hTrail was identitied by RT-PCR after amplification and transfected U251 cells,X-ray of 0,2,5,8,10,12,15,18 Gy was given 48 h after the transfection,the expression level of TrailmRNA was detected by real-time quantitative-PCR.Results The expressed level of TrailmRNA started to increase at 1hour post-irradiation,and maintained a high level from 4 hour to 8 hour.The expressed level of TrailmRNA increased with the radiation dose increasing,and rase the highest at the the point of 12Gy point,then began to descend.Conclusion Egr-1 promoter can be activated by ionizing irradiation and regulate the expression of Trail gene in vitro.The expression of Trail gene is correlated with radiation dose and time interval after irradiation.