Effect of cyclin D1 on HBV transcription and replication / 临床肝胆病杂志

ABSTRACT

Objective To investigate the effect of cyclin D1 (with CCND1 as the gene name) on HBV replication and its potential mechanism. Methods With reference to GSE84044 dataset, the Spearman's rank correlation analysis was used to investigate the correlation between the expression levels of genes in liver tissue and serum HBV DNA load in patients with HBV-related liver fibrosis. Cyclin D1 and cyclin D1 T286A mutant were transiently expressed in the HBV cell replication model, and time-resolved immunofluorescence and quantitative real-time PCR were used to measure the levels of HBsAg/HBeAg and HBV DNA in cell culture supernatant; Western blot was used to measure the level of HBV core protein in cells; reverse-transcription quantitative real-time PCR was used to measure the level of HBV RNA in cells; dual-luciferase reporter assay was used to observe the effect of cyclin D1 on the activity of HBV basic core promoter (BCP). GSE83148 dataset was used to investigate the correlation between CCND1 and HBV-related regulatory factors. The independent samples t -test was used for comparison of normally distributed continuous data between two groups, and the Mann-Whitney U test was used for comparison of non-normally distributed continuous data between two groups. Results The analysis of GSE84044 data showed that 7 cell cycle genes were significantly negatively correlated with HBV DNA load in liver tissue of the patients with HBV-related liver fibrosis (all r < -0.3, all P < 0.05), which included the CCND1 gene ( r =-0.474, P < 0.001). Exogenous expression of cyclin D1 and cyclin D1 T286A mutant reduced the levels of HBsAg, HBeAg, and HBV DNA in culture supernatant of the HBV replication cell model, as well as the levels of HBV core protein and HBV RNA in cells. Exogenous expression of cyclin D1 significantly inhibited the transcriptional activity of HBV BCP. The expression level of CCND1 in liver tissue of chronic hepatitis B patients was significantly positively correlated with the expression of APOBEC3G ( r =0.575, P < 0.001), SMC5 ( r =0.341, P < 0.001), and FOXM1 ( r =0.333, P < 0.001) which inhibited HBV replication, while it was significantly negatively correlated with the expression of the HBV entry receptor NTCP ( r =-0.511, P < 0.001) and HNF1α as the transcription factor for positive regulation of HBV replication ( r =-0.430, P < 0.001). Overexpression of cyclin D1 in HepG2 cells reduced the transcriptional levels of HNF1α and NTCP. Conclusion Cyclin D1 inhibits HBV transcription and replication possibly by downregulating the expression of HNF1α and NTCP.