Inhibition Of USP18 Expression Inhibits Human Hepatocellular Carcinoma Cell Line Of Hep3B

Purpose:To detect the expression of USP18 in hepatoma carcinoma cells and influence on biological activity(cell proliferation,cell clone,cell cycle and cell apoptosis) Methods:In the first place, The m RNA and protein levels of USP18 in cells of HepG2、Hep3B 、 HepG2.2.15 、 Huh7 、 SMMC-7721 were determined with reverse transcription-PCR and western blotting and the highest expressed cell was selected for RNAi experiment. In addition, three groups of specific USP18 targeted siRNA and negative control group were designed. Liver cancer cells were instantaneously transfected using lipofectamine method.Finally, we transfected them to hepatoma carcinoma cell and detected the interfering efficiency through reverse transcriptionPCR and Western-blot, and then carried out the next tests: MTT cell proliferation test, flat plate clone formation test, cell cycle test and apoptosis test. Results:RT-PCR and Western blot indicated that was high expressed in the five liver cancer lines, and interestingly higher expressed in HBV-positive hepatoma cells than HBV-negative ones. After interference of USP18, Expression of USP18 at the level of mRNA and protein in USP18-siRNA groups were significantly inhibited Compared with the normal group and the negative control group, especially in USP18-siRNA-1 group, MTT assay and Tablet cloning assay revealed that the number of cell proliferation and cloning efficiencies slowed down obviously compared to the control group and the negative control group, cell cycle was blocked at G1 phase and the percentage of apoptotic increased. Conclusions:Hep3B was the highest expression of USP18 in the five liver cancer lines.siRNA-targeting USP18 can markedly inhibited the expression of USP18 in liver cancer Hep3 B cells, and decrease the abilities of proliferation and cloning efficiencies,promote the abilities of cell apoptosis and block G1 phase of cell cycle of liver cancer cells, especially in USP18-siRNA-1 group.