PER1对人肝癌细胞BEL-7402辐射敏感性的影响

Effect of PER1 on Radiosensitivity of Human Hepatoma Cell Line BEL-7402

本文通过X射线照射SMMC-7721、BEL-7402和HepG2三种肝癌细胞后,以克隆形成试验检测其存活分数,结果显示在梯度剂量X射线0、2、4、6、8、10 Gy照射下SMMC-7721、BEL-7402、HepG2三种细胞克隆存活分数逐渐下降,其中SMMC-7721在三种肝癌细胞系中对辐射最敏感,BEL-7402辐射抗性在三种肝癌细胞系中最高。Western blot检测发现PER1在SMMC-7721中的表达水平明显显著高于BEL-7402和HepG2(P<0.05)。过表达PER1蛋白以后,BEL-7402接受5 Gy X射线照射后凋亡明显增多,同时,western blot和RT-qPCR试验结果发现,X射线照射过表达PER1的BEL-7402细胞,抗凋亡蛋白Bcl-2表达明显降低,凋亡执行蛋白Caspase-3断裂明显增多。研究结果表明PER1蛋白的高水平表达可以促进X射线诱导的凋亡,增强肝癌细胞的辐射敏感性。

In this study,SMMC-7721,BEL-7402 and HepG2 hepatoma cells were irradiated by X-rays,and the survival fraction was detected by colony formation assay;PER1 expression was detected by western blot and RT-qPCR;Flow cytometry was used to detect apoptosis.The results showed that the survival fraction of SMMC-7721,BEL-7402 and HepG2 cells decreased gradually under X-ray irradiation of 0,2,4,6,8,10 Gy,among which SMMC-7721 was the most sensitive one to radiation,while the radioresistance of BEL-7402 was the highest.Western blot analysis showed that the expression level of PER1 in SMMC-7721 was significantly higher than that of BEL-7402 and HepG2(P<0.05).After overexpression of PER1 protein,apoptosis rate of BEL-7402 cells exposed to 5 Gy X-ray irradiation was significantly increased.At the same time,western blot and RT-qPCR showed that expression of anti-apoptotic protein Bcl-2 was significantly decreased,and the cleavage of apoptosis-executing protein caspase-3 was significantly increased in BEL-7402 cells overexpressing PER1.The results showed that high level expression of PER1 protein can promote X-ray induced apoptosis and enhance the radiosensitivity of liver cancer cells.