抗增殖蛋白Tob1对人类宫颈癌细胞系HeLa放射敏感性影响的实验研究

Study on the effects of anti-proliferative protein Tob1 on the radio-sensitivity of human cervix cancer cell line HeLa

为探讨抗增殖蛋白家族成员Tob1(transducer of ErbB2,1)对宫颈癌细胞系HeLa放射敏感性的影响,构建可表达Tob1基因全长的重组质粒pcDNA3.0-Tob1(pc3/Tob1),采用脂质体介导转染入HeLa细胞,经G418筛选出阳性耐抗克隆。通过集落形成实验研究Tob1对HeLa细胞放射敏感性的影响,借助流式细胞术和WesternBlot法检测相关分子机制。结果显示,较之HeLa母细胞和转染"空"质粒pcDNA3.0的HeLa/pc3细胞,转染pc3/Tob1后HeLa细胞放射敏感性明显增加;Tob1蛋白高表达增加了HeLa细胞中由辐射诱导的细胞凋亡,提高了由辐射引起的Bax蛋白的表达,降低了Bcl2蛋白表达。上述结果提示Tob1提高了HeLa细胞对电离辐射的敏感性,其机制可能与其上调Bax蛋白的表达、下调Bcl2蛋白的表达,从而增加由辐射诱导的细胞凋亡有关。

In order to investigate the effects of human anti-proliferative protein Tob1 （transducer of ErbB2,1） on the radio-sensitivity of human cervix cancer cells HeLa,the full length Tob1 recombinant plasmid pcDNA3.0/Tob1 （pc3/Tob1） was constructed and transfected into HeLa cells by lipofectamine. And G418 selection was used to get HeLa cell line stably expressed exogenous Tob1. The clonogenic assay was applied to study the effects of Tob1 on HeLa cell radio-sensitivity,while flow cytometry assay and Western Blot analysis were performed to determine the related mechanisms. It was shown that,compared with parental HeLa cells and mock plasmid pcDNA3.0 transfected HeLa/pc3,the radio-sensitivity of HeLa cells transfected with Tob1 was increased obviously. It was also found that increased Tob1 expression could enhance cell apoptosis of HeLa induced by irradiation,while up-regulated protein expression level of Bax,but down-regulated Bcl2 expression occur at the same time. These results suggested that Tob1 might play a role as radio-sensitizer of cervix cancer cell line HeLa via regulating the expression of apoptosis related genes.