The Expression Of SIRT1is Correlated With Tumorgenesis And Progression Of Hepatocarcinoma

In this paper, we focus on how the gene SIRT1affects the process, such asproliferation, migration, colony formation and maintenance of hepatoma stem cells, ofin the hepatoma cell lines Hep3B、PLC/PRF/5and Huh7.BACKGROUND: SIRT1is among the class III of nicotinamide adenine dinucleotide(NAD+)-dependent histone deacetylase enzymes, belonging to silencing regulation2(silent information regulator2, Sir2) family. SIRT1gene expression was modified onmRNA level in liver cancer cell occurs, while SIRT1deacetylase activity wasregulated by protein-protein interaction and sumoylation.The expression of SIRT1, in a variety of solid tumors, is up-regulated and affectsdownstream targets by direct binding. SIRT1regulates apoptosis-associated factors,silences tumor suppressor genes, promotes multidrug resistance gene (MDR1)expression and affect chemotherapy and radiation treatment of cancer.AIM: Using lentivirus carrying the shRNA aimed to down-regulate expression ofSIRT1, we study its functions in hepatoma cell lines Hep3B, PLC and Huh7.METHODS: First, we constructed lentiviral vector pLKO.1-Sh-SIRT1carryinginterference sequences shRNA of SIRT1and transfected the plasmids into HEK293Tcells to produce lentivirus Lv-Sh-SIRT1. The validity of shRNA-mediated SIRT1downregulation was identified by Western blotting (WB), and we constructedhepatoma cell lines with down-regulated expression of SIRT1. Then, using cellproliferation kit CCK8, we investigate the change in the function of cell proliferation;using transwell migration assay, we test the change in the function of migration; usingcolony formation assay and sphere formation assay, we study the change in thefunction of colony formation and sphere formation. Finally, data was analyzed usingstatistical methods. RESULTS: With lentivirus carrying shRNA to silence the expression of SIRT1inhepatoma cells including Hep3B, Huh7and PLC/PRF/5, through the technologiesincluding the proliferation assay, transwell assay, cloning assay and sphere formationassay to detece if the function of the hepatoma cells had changed. Compared with thenegative control, we found that Hep3B, Huh7and PLC/PRF/5cells were inhibited inproliferation, the migration of Hep3B and Huh7cells were ignificantly decreased,whereas PLC/PRF/5cells may not have significant reaction. The volume and amountof the clone derived from these hepatoma cells whose expression of SIRT1wasdecreased is smaller and fewer, so is the efficiency of the clone formation. Thefunction of self-renew is similar in these cells and the volume and amount of thesphere formed by these hepatoma cells is also smaller and fewer.CONCLUSION: These results show that hepatocarcinoma cells that the expressionof SIRT1was down regulated, including Hep3B, Huh7and PLC/PRF/5, cansignificantly inhibit the function of the proliferation and migration of cells, colonyformation and self-renewal of hepatoma stem cells, but the migration ability may notbeen affected in PLC/PRF/5cell.