Résumé
Objective To investigate the effect of retrotransposon LINE-1 encoding proteins LINE-1 ORF-1p on proliferation ability of hepatocellular carcinoma cell lines and hepatic immortalized cell lines. Methods siRNA expression vector for LINE-1 ORF-1 encoding sequence (LINE-1 ORF-1p psilence2.1-U6-siRNA) was structured. Hepatocellular carcinoma cell lines (Bel-7402, SMMC-7721, HepG2) and hepatic immortalized cell line (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 blotting assay. The effect of LINE-1 ORF-1p expression reduction on the proliferation ability of these cells was identified using the MTT method. Result In the hepatocellular carcinoma cells (Bel-7402, SMMC-7721, HepG2) and hepatic immortalized cell (LO2), the transfection of LINE-1 ORF-1p siRNA expression vector reduced the expression level of LINE-1 ORF-1p. Moreover, it significantly inhibited the proliferation of the above cells on the third day (P<0.05). The inhibition rates were 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 hepatic immortalized cells.