TRIM26 Inhibits Hepatitis B Virus Replication And TRIM26 Genetic Polymorphism Predicts Interferon Treatment Response Of Chronic Hepatitis B Patients

Background and objection:Hepatitis B virus(HBV)infection is a serious global health problem,patients with HBV infection have a high risk of developing chronic hepatitis B(CHB),liver fibrosis,cirrhosis,and even hepatocellular carcinoma(HCC).At present,two kinds of drugs are recommended for the treatment of HBV infection,including nucleoside(t)ide analogues(NAs)and interferon(IFN).However,due to the integration of HBV genome with host genes and the existence of covalently closed circular DNA(cccDNA),HBV infection is difficult to be completely cured.As an E3 ubiquitinase,interferon stimulating gene TRIM26 has been proved to affect Hepatitis C virus(HCV)replication.Therefore,this study aimed to explore the effect of TRIM26 on HBV replication.Methods:Western blot was used to verify the expression of TRIM26 in Huh7,HepG2,HepAD38,and HepG2.2.15 cells.Then,the effect of TRIM26 on HBV replication was explored by knocking down or overexpressing TRIM26 in HepAD38,HepG2.2.15 and HBV infected HepG2-NTCP cells.Subsequently,co-immunoprecipitation(co-IP)assay and western blot confirmed the specific components of HBV binding to TRIM26 and the specific mechanism between TRIM26 and HBV.A total of 945 chronic hepatitis B patients received PegIFN-αwere utilized to evaluated the relationship between TRIM26_rs116806878 and IFN treatment response.Results:1.The expression of TRIM26 in Huh7 and HepG2 cells was significantly higher than that in HepAD38 and HepG2.2.15 cells,so we speculated that HBV infection may inhibit the expression of TRIM26.2.HBV infection inhibited TRIM26 expression.3.HBV replication was enhanced after knockdown of TRIM26 in HepAD38,HepG2.2.15 and HBV infected HepG2-NTCP cells.On the contrary,HBV replication was weakened after overexpression of TRIM26.4.Co-IP confirmed that TRIM26 could bind to HBx,and cell immunofluorescence also confirmed the co-localization of TRIM26 and HBx in the cytoplasm.Further mechanism studies show that TRIM26 binds to HBx through its SPRY domain and mediates ubiquitination and degradation of HBx,thereby inhibiting HBV replication.5.Human recombinant IFN α,β,and γ stimulation increased the expression of TRIM26 in Huh7 and HepG2 cells.6.The analysis of clinical cohort showed that TRIM26_rs116806878 could predict treatment response of PegIFN-α-treated CHB patients,which indicated by HBeAg seroconversion and HBV DAN level.7.A polygene score(PGS)system was constructed by integrating TRIM26_rs11680878,STAT4_rs7574865 and CFB_rs12614,which could better predict PegIFN-α treatment response of CHB patients.Conclusion:The overexpression of TRIM26 can inhibit HBV replication and IFN promotes TRIM26 expression.TRIM26 exerts an inhibitory effect on HBx by promoting ubiquitin-mediated degradation of HBx.Furthermore,TRIM26_rs116806878 is a potentially predictive biomarker of response to PegIFN-α treatment of CHB patients,which may shed new light on HBV therapy and clinical medication strategy.