Zinc finger E-box-binding homeobox 2 inhibits hepatitis B virus replication and expression

Abstract

Objective: To investigate the effect of zinc finger E-box-binding homeobox 2 (ZEB2) on hepatitis B virus (HBV) replication and expression. Methods: HepG2, HepG2.2.15, and HepAD38 cells were cultured separately, and Western blot was used to measure the expression of ZEB2. HepG2.2.15 cells were cultured and transfected with ZEB2 expression plasmids or shRNA targeting ZEB2. Western blot was used to measure the expression of ZEB2 and HBV core proteins, quantitative real-time PCR was used to measure HBV 3.5 kb RNA and HBV DNA, Southern blot was used to measure HBV replicative intermediate, and ELISA was used to measure the expression of HBsAg and HBeAg, in order to clarify the effect of ZEB2 on HBV replication and expression. The dual-luciferase reporter system was used to analyze the effect of ZEB2 on HBV promoter, and the chromatin immunoprecipitation assay was used to detect the binding of ZEB2 to HBV promoter. The t-test was used for comparison of means between groups. Results: The expression of ZEB2 was inhibited in the cells with HBV replication. Overexpression of ZEB2 reduced the level of HBV replication and expression by about 50% (P< 0.05). After ZEB2 was downregulated by shZEB2-1 or shZEB2-2, the level of HBV replicative intermediate increased from 58.53 ± 3.43 to 112.80 ± 5.03, and 128.30 ± 2.31, the relative expression level of HBV 3.5 kb RNA increased from 1.00 ± 0.01 to 2.03 ± 0.02 and 2.32 ± 0.03, the level of HBsAg increased from 35.63% ± 1.57% to 81.87% ± 0.43% and 100.00% ± 2.18%, and HBeAg increased from 37.00% ± 0.70% to 88.00% ± 2.60% and 100.00% ± 0.75%. Furthermore, ZEB2 could bind to HBV core promoter and inhibit its transcriptional activity. Conclusion: ZEB2 inhibits HBV replication and expression through binding to HBV core promoter and inhibiting its transcriptional activity.