The Research Of SET8 Regulation For Hepatocellular Carcinoma Outcome

Objective: SET8(also known as PR-Set7/9, SETD8, KMT5A), a member of the SET domain-containing methyltransferase family specifically targeting H4K20 for monomethylation, has been implicated in a diverse array of biological processes, such as controlling gene transcription, modulating replication origins, maintaining genome integrity, and regulating cell-cycle progression and development, through its histone monomethylating activity.These implications largely increase the probability that SET8 involves in oncogenesis and progression of tumors. We found that the expression levels of SET8 was associated with survival of hepatocellular carcinoma(HCC)previously. In present study, we assess the effect of SET8 gene on proliferatio,apoptosis,invasiveness and migration of human hepatocarcinoma SMMC-7721 cells.Methods:1 Four fluorescein-labeled SET8 siRNAs were transfected into SMMC-7721 cells by LipofectamineTM2000 kit. The effective knock down of SET8 was screened by western blotting techniques.The subsequent assays were performed among SET8-siRNA tranfected cells, control-siRNA transfected cells and untreated blank control cells.2 MTS assay was used to determine the effect of SET8 on SMMC-7721 cells proliferation activity.3 The Annexin V- PE/7-AAD double staining method was used for apoptosis assay.4 The wound scrape assay and Transwell migration assay were used to detect the ability of SMMC-7721 cells migration.5 The Matrigel invasion assay was used to detect the ability of SMMC-7721 cells invasion.Results:1 The SET8 siRNA-2 could dramatically silence the expression of SET8 in SMMC- 7721 cells with a inhibition rates of 63.9% comparing with that of controls.2 Compared with Control-siRNA and Blank control group, the proliferation rate of SMMC- 7721 cells was significantly decreased from 24 h to 72 h after SET8 siRNA-2 transfected(p<0.01). MTS assay indicated that knock down of SET8 could significantly inhibit HCC cells proliferation.3 Compared with Control-siRNA and Blank control group, the apoptosis rate of SMMC- 7721 cells was no obvious difference after SET8 siRNA-2transfected(p>0.05). Flow cytometry indicated that knock down of SET8 could not promote cell apoptosis in human hepatocarcinoma cells.4 Compared with Control-si RNA and Blank control group, crawing speed and wound healing migration of SMMC- 7721 cells was significantly slowed down at 24 h and 48 h after SET8 si RNA-2 transfected(p<0.01).Transwell migration assay showed that the migrated cells through the Transwell was dramatically decresed in SET8 siRNA-2 transfected group(p<0.01). These data indicated that knock down of SET8 could inhibit the migration ability of HCC cells.5 Compared with Control-siRNA and Blank control group, the number of invaded SMMC-7721 cells was significantly decreased in SET8 siRNA-2transfection group(p<0.01). The Matrigel invasion assay indicated that knock down of SET8 could inhibit the invasion ability of HCC cells.Conclusion: SET8 could modify the outcome of HCC through inhibiting proliferation,invasiveness and migration of HCC cells.