LINE-1 ORF-1p对肝脏肿瘤细胞系和肝源永生化细胞系增殖的调控作用

Regulatory effect of LINE-1 ORF-1p on hepatocellular carcinoma cells and proliferation of immortalized hepatocellular cells

目的研究反转座子LINE-1编码蛋白LINE-1 ORF-1p对肝脏肿瘤细胞系以及肝源永生化细胞系增殖能力的影响。方法构建针对LINE-1 ORF-1编码序列的siRNA表达载体(LINE-1 ORF-1p psilence2.1-U6-siRNA),转染肝脏肿瘤细胞系Bel-7402、SMMC-7721、HepG2和肝源永生化细胞系LO2。采用Western blotting检测LINE-1 ORF-1p siRNA表达载体对LINE-1 ORF-1编码蛋白LINE-1 ORF-1p表达的影响,采用MTT法检测LINE-1 ORF-1p表达受抑对细胞增殖的影响。结果在肝脏肿瘤细胞HepG2、Bel-7402、SMMC-7721和肝源永生化细胞LO2中,转染LINE-1 ORF-1p siRNA表达载体均能降低LINE-1 ORF-1p的表达水平,并从第3天起显著抑制前述细胞的增殖(P<0.05),其抑制率分别为63%、51%、40%、43%。结论抑制LINE-1 ORF-1p蛋白表达后可使肝脏肿瘤细胞系和永生化细胞系的增殖受抑。

Objective The present study investigates the effect of retrotransposon LINE-1 encoding proteins LINE-1 ORF-1p on hepatocellular carcinoma cells and the proliferation ability of immortalized hepatocellular cells.Methods siRNA expression vector for LINE-1 ORF-1 encoding sequence（LINE-1 ORF-1p psilence2.1-U6-siRNA） was structured.Hepatocellular carcinoma cells（Bel-7402,SMMC-7721,HepG2） and immortalized hepatocellular cell（LO2） were transfected.The effect of LINE-1 ORF-1p siRNA expression vector on the expression of LINE-1 ORF-1 encoding protein LINE-1 ORF-1p was detected using the Western blot assay.The effect of the reduction of LINE-1 ORF-1p expression on the proliferation ability of these cells was identified using the MTT method.Result In hepatocellular carcinoma cells（Bel-7402,SMMC-7721,HepG2） and the immortalized hepatocellular cell（LO2）,the transfection of LINE-1 ORF-1p siRNA expression vector could reduce the expression level of LINE-1 ORF-1p.Moreover,it could inhibit significantly the proliferation of the above cells on the third day（P〈0.05）.The inhibition rates are as follows： Bel-7402,51%;HepG2,63%;SMMC-7721,40%;and LO2,43%.Conclusion The inhibition of LINE-1 ORF1p protein expression can inhibit the proliferation ability of hepatocellular carcinoma cells and the immortalized hepatocellular cell.