Transcription Factor E2F4 Promotes Proliferation, Migration And Invasion Of Hepatocellular Carcinoma Cells

Objective:The transcription factor F4(E2F4)plays an important role in the development of many tumors.In this paper,we examined the expression of E2F4 in hepatocellular carcinoma(HCC)tissues and hepatoma cells Huh7 and Hep3 B,and explored the effect of E2F4 expression on the proliferation,migration and invasion ability of hepatoma cells.Methods:Real-time fluorescence quantitative reverse transcription polymerase chain reaction(qRT-PCR)was used to detect the expression level of E2F4 mRNA in 40 pairs of primary liver cancer tissues and their corresponding adjacent tissues.To analyze the relationship between the expression of E2F4 in liver cancer tissues and the clinical pathological indicators of patients.The expression levels of E2F4 in human hepatoma cell lines Huh7,Hep3 B and normal liver cells LO2 were detected using qRT-PCR.Huh7 was transfected with E2F4 overexpression plasmid pcDNA3.1-E2F4,and Hep3 B was infected with E2F4 interfering adenovirus Ad-siE2F4.After treatment,the status of cells was monitored by Incucyte Zoom long-term cell dynamic monitoring instrument.The cell proliferation and Migration ability.Transwell method was used to detect the invasive ability of cells.Flow cytometry was used to analyze the level of cell apoptosis and cycle progression,and Western blotting was used to detect epithelial-mesenchymal transition(EMT)-related markers N-cadherin and E-cadherin and cell cycle-dependent kinases(CDKs)Protein expression.RESULTS:In HCC tissues,the expression level of E2F4 mRNA was significantly higher than that in adjacent tissues(P<0.01),and E2F4 was closely related to the size of tumor tissues(P<0.01).The expression levels of E2F4 mRNA in liver cancer cell lines Huh7 and Hep3 B cells were higher than those in normal liver cells LO2(both P<0.01).Overexpression of E2F4 in HCC cells can enhance the cell's ability to proliferate,migrate and invade(P<0.01).When E2F4 is disturbed,the ability of HCC cells to proliferate,migrate and invade decreases(P<0.01).The expression of E-Cadherin in liver cancer cells is very small,and it is N-Cadherin protein that exerts EMT function.The expression of N-Cadherin in Huh7 cells was significantly reduced after E2F4 overexpression,and the expression of N-Cadherin was significantly increased after E2F4 was interfered(P<0.01).Flow cytometry results showed that E2F4 had no obvious relationship with apoptosis,but E2F4 could promote the cell cycle progression(P<0.01).The expression of CDK1,CDK2 and CDK6 protein had no obvious relationship with E2F4,and E2F4 could stimulate the expression of CDK4(P<0.01).Conclusion:The expression of E2F4 is increased in HCC tissues and cell lines.E2F4 can promote the proliferation of HCC cells by promoting the progress of the cell cycle,and enhance the migration and invasion ability of HCC cells by promoting the EMT process.