miR-29a promotes hepatitis B virus replication and expression by targeting SMARCE1 in hepatoma carcinoma.

AIM: To investigate the functional role and underlying molecular mechanism of miR-29a in hepatitis B virus (HBV) expression and replication. METHODS: The levels of miR-29a and SMARCE1 in HBV-infected HepG2.2.15 cells were measured by quantitative real-time PCR and western blot analysis. HBV DNA replication was measured by quantitative PCR and Southern blot analysis. The relative levels of hepatitis B surface antigen and hepatitis B e antigen were detected by enzyme-linked immunosorbent assay. The Cell Counting Kit-8 (CCK-8) was used to detect the viability of HepG2.2.15 cells. The relationship between miR-29a and SMARCE1 were identified by target prediction and luciferase reporter analysis. RESULTS: miR-29a promoted HBV replication and expression, while SMARCE1 repressed HBV replication and expression. Cell viability detection indicated that miR-29a transfection had no adverse effect on the host cells. Moreover, SMARCE1 was identified and validated to be a functional target of miR-29a. Furthermore, restored expression of SMARCE1 could relieve the increased HBV replication and expression caused by miR-29a overexpression. CONCLUSION: miR-29a promotes HBV replication and expression through regulating SMARCE1. As a potential regulator of HBV replication and expression, miR-29a could be a promising therapeutic target for patients with HBV infection.

Notch Signaling Modulates the Balance of Regulatory T Cells and T Helper 17 Cells in Patients with Chronic Hepatitis C.

The imbalance of regulatory T cells (Tregs) and T helper 17 (Th17) cells contributes to the persistent hepatitis C virus (HCV) infection. However, modulatory factors associated with Tregs-Th17 balance were not fully elucidated. A recent study demonstrated an immunoregulatory strategy by inactivation of Notch signaling to reverse the disequilibrium of Tregs-Th17 cells in immune thrombocytopenia. Thus, the aim of this study was to assess the effect of Notch signaling in regulating the functions of Tregs and Th17 cells in chronic hepatitis C. A total of 46 patients with chronic hepatitis C and 17 normal controls (NCs) were enrolled. mRNA expressions of Notch1 and Notch2 were semiquantified by real-time reserve polymerase chain reaction. Percentages of Tregs-Th17, levels of key transcriptional factors, and cytokine productions were measured in response to treatment by DAPT, a γ-secretase inhibitor to suppress Notch signaling. We found that Notch1 and Notch2 mRNAs were significantly elevated in peripheral blood mononuclear cells from chronic hepatitis C patients compared with those from NCs. DAPT treatment reduced Th17 response by downregulation of RORγt expression and interleukin (IL)-17/IL-22 secretion. Tregs proportion, FoxP3 expression, and IL-10 production did not change significantly with DAPT treatment in chronic hepatitis C; however, blockage of Notch signaling inhibited the suppressive function of Tregs. Moreover, effective anti-HCV therapy not only reduced Notch1 and Notch2 expression but also decreased Tregs and Th17 proportions. The current data provided a novel mechanism underlying the modulation of Treg-Th17 balance. The link between Notch signaling and Th cells might lead to a new intervention for breaking immunotolerance of chronic HCV infection.

The prevalence and determinants of drug-resistance-associated mutations in the HIV-1-infected MSM population of Henan Province in China.

To estimate the prevalence of human immunodeficiency virus (HIV) drug resistance (DR) in a population of men who have sex with men (MSM) from Henan Province of China and to identify the DR-associated HIV-1 mutations in these MSM. The HIV-positive status of the MSM subjects in this study was confirmed using ELISA and Western blotting. The MSM subjects were classified into non-treatment group (n = 106) and treatment group (n = 313). CD4(+) T-lymphocyte counts were obtained by flow cytometry, and viral load was measured by branched DNA (bDNA) signal amplification assay. HIV-1 genotypic resistance tests were performed by sequence analysis of the HIV-1 protease and reverse transcriptase genes. In the non-treatment group, 15 patients (14.2 %) displayed DR to non-nucleoside reverse transcriptase inhibitor (NNRTI). In the treatment group, the failure rate of viral suppression was 38.33 % and the DR rate was 33.2 %, which was higher than the rate observed in the non-treatment group (P < 0.05). The incidence of mutations corresponding to NNRTI resistance was significantly higher than the incidence of mutations corresponding to nucleoside reverse transcriptase inhibitor (NRTI) resistance (32.9 % vs. 26.5 %) in the cohort. After antiretroviral therapy (ART), the frequencies of K103N, G190A, Y181C, and V106A mutations were highly elevated. Logistic regression analysis results showed that duration of treatment, poor treatment compliance, drug abuse and homosexual orientation are the major risk factors for DR in this MSM population (all P < 0.05). Our results showed that DR-associated mutations in the HIV-1-infected MSM population increased significantly after ART. Furthermore, duration of treatment, poor treatment compliance, drug abuse and homosexual orientation were identified as the risk factors for DR in the MSM population from Henan Province in China.

Increased miR-16 expression induced by hepatitis C virus infection promotes liver fibrosis through downregulation of hepatocyte growth factor and Smad7.

Hepatitis C virus (HCV) is involved in the initiation and progression of liver fibrosis by regulating genes encoding host proteins. However, the underlying mechanism of HCV-induced liver fibrosis is still to be determined. Reverse transcription polymerase chain reaction (RT-PCR) and western blot were performed to investigate the effect of HCV infection on the expression of the cellular microRNA miR-16 and its target genes encoding hepatocyte growth factor (HGF) and Smad7 in patients infected with HCV and in a liver cell line, QSG-7701, transfected with Ad-HCV, a recombinant adenovirus construct for expression of the HCV core protein. Regulation of HGF and Smad7 expression by miR-16 was assessed using luciferase reporter construct assays and miR-16 mimic transfection. Interferon-α (IFN-α) was used to verify the alteration of gene expression induced by HCV in QSG-7701 cells. Here, we found that miR-16 levels were increased in patients with HCV infection and were correlated with HGF and Smad7 expression levels in patients with HCV infection. Furthermore, HGF and Smad7 were predicted by bioinformatics analysis to be targets of miR-16. Upregulation of miR-16 and decreased HGF and Smad7 expression were still shown in QSG-7701 cells infected with Ad-HCV. Additionally, interferon-α (IFN-α) could reverse the changes in gene expression induced by HCV infection. These results suggest that the upregulation of miR-16 expression induced by HCV infection is a novel mechanism that contributes to downregulation of HGF and Smad7 in the development of liver fibrosis.