Study On The Mechanism Of Muscle Enhancement Factor MEF2D Enhanced Invasion And Metastasis Of Hepatocellular Carcinoma By Inducing EMT

Objective The study is aimed to study whether MEF2 D is involved in the process of TGF-?-induced EMT and its relationship with invasion and metastasis of Hepatocellular carcinoma(HCC)and its mechanism related to this process.We plan to evaluate MEF2 D as a molecular marker for metastasis of hepatocellular carcinoma(HCC)in clinical treatment.Methods Huh-7 and PLC/PRF/5 cells were treated with TGF-?,and then,we observed cell morphology.Data analysis and Western blotting were also used to verify the changes in the expression of MEF2 D and EMT-related markers.The overexpression of MEF2 D in stably-transformed cell lines was established in lentivirus-infected cells,and then,cells were treated with the same concentration of TGF-?.We verified that MEF2 D promoted the process of TGF-?-induced EMT.We studied the effect of MEF2 D on invasion and metastasis of hepatoma cells with overexpression or knockout of MEF2 D.To study the mechanism of MEF2D's promoting invasion and metastasis,we sequenced and conducted molecular biology experiments.Then,we detected the relationship between MEF2 D expression level and hepatocellular carcinoma by immunohistochemistry and Western blotting,as well as the relationship between the expression of MEF2 D and invasion and metastasis of hepatocellular carcinoma via data analysis and quantitative PCR.Results We confirmed that MEF2 D plays an important role in the TGF-?-induced EMT by observing changes in cell morphology and key molecules.The cell lines were subjected to Transwell and scratch assays in the conditions of overexpression or knockout of MEF2 D,and found that MEF2 D could promote the invasion and metastasis of HCC cells.It was also found that MEF2 D promotes cell invasion and metastasis by binding to the promoter of Twist1 and activating the transcription of Twist1,evidenced by fluorescence quantitative PCR,Western blot and molecular biological experiments.Through detecting the clinical samples and analyzing big data,we found that the high expression of MEF2 D was associated with metastasis of HCC,and also predicted the worse prognosis of HCC patients.Conclusion We confirmed that MEF2 D participates in the EMT process induced by TGF-? and MEF2 D plays an important role for HCC development.Besides,MEF2 D could significantly promoted the invasion and metastasis of hepatoma cells by binding to the promoter of Twist1.Finally,we found that MEF2 D is involved in tumorigenesis,and it promotes the invasion and metastasis of HCC.Our study provides a new marker biomolecule for the metastasis and recurrence of HCC.