Ku70对辐射诱导的BRCA1表达的影响

Study on the regulation of BRCA1 by Ku70 induced by irradiation

为探讨核蛋白Ku70对经?射线照射后乳腺癌易感基因BRCA1表达的影响,本研究通过靶向升高或降低Ku70,观察了Ku70基因对BRCA1蛋白和mRNA表达水平的影响,以及Ku70对照射后SGC7901、EC109、H460 3种肿瘤细胞BRCA1表达的影响。结果表明:经siKu70处理的3种肿瘤细胞BRCA1的蛋白和mRNA表达水平明显下降,并且对辐射诱导的BRCA1表达也有抑制作用;转染了Ku70高表达质粒的3种肿瘤细胞BRCA1的表达水平也较对照组明显升高,且转染后照射组BRCA1表达水平高于单纯照射组。结果提示,Ku70对BRCA1的表达具有调节作用,可能从转录水平参与了辐射诱导的BRCA1升高。

To explore the effect of Ku70 on breast cancer susceptibility genes BRCA1 after irradiation,the BRCA1 protein and its mRNA expression after transfecting into tumor cells with siKu70 or Ku70 plasmid DNA,and the impact of Ku70 on BRCA1 expression in SGC7901,EC109 and H460 cell lines were investigated after irradiation.The results indicate that both protein and transcription of BRCA1 were obviously reduced in tumor cell lines after pretreated with siKu70,and siKu70 can reduce radiation-induced BRCA1.Similarly,after transfection of Ku70 plas-mid DNA,expression of BRCA1 was higher than that of the control group meanwhile there was a significant incre-ment of BRCA1 in irradiation group compared with that of no irradiated group.The results suggest that Ku70 gene might be relative to BRCA1 expression,and it might be involved in radiation-induced BRCA1 at transcriptional level.