Suppression of ceramide-induced cell death by hepatitis C virus core protein

Hepatitis C virus and hepatocellular carcinoma

Hepatitis C virus (HCV), a hepatotropic virus, is a single stranded-positive RNA virus of ~9,600 nt. length belonging to the Flaviviridae family. HCV infection causes acute hepatitis, chronic hepatitis, cirrhosis and hepatocellular carcinoma (HCC). It has been reported that HCV-coding proteins interact with host-cell factors that are involved in cell cycle regulation, transcriptional regulation, cell proliferation and apoptosis. Severe inflammation and advanced liver fibrosis in the liver background are also associated with the incidence of HCV-related HCC. In this review, we discuss the mechanism of hepatocarcinogenesis in HCV-related liver diseases.

Subversion of innate host antiviral strategies by the hepatitis C virus

Since its discovery in 1989, Hepatitis C Virus (HCV) has been recognized as a major cause of chronic hepatitis, end-stage cirrhosis and hepatocellular carcinoma affecting world wide more than 210 million people. The fact that 80% of newly infected patients fail to control infection, the slow development of overt disease and immune-response as well as the unsatisfying results of current IFN/ribavirin combination therapy suggests that the hepatitis C virus developed powerful strategies to evade and to antagonize the immune response of the host and to resist the antiviral actions of interferons. During the last 10 years several viral strategies have been uncovered for control and evasion from cellular antiviral host response initiated by the pathogen-associated molecular pattern recognizing receptors RIG1 and TLR3 and mediated by the release of type I interferon and subsequent induction of interferon stimulated genes. This review highlights recent results providing an idea of how the hepatitis C virus interferes with the different steps of initial antiviral host-response and establishes persistent infection.

Expression of Ki-67, transforming growth factor beta1, and B-cell lymphoma-leukemia-2 in liver tissue of patients with chronic liver diseases

BACKGROUND

The purpose of the present paper was to assess expression of proliferation, fibrosis and apoptosis markers in different phases of chronic liver diseases.

METHODS

Sixty-six adults with chronic liver diseases (chronic hepatitis C, n = 48; chronic hepatitis B, n = 10; alcohol chronic liver disease, n = 8) treated at the Department of Infectious Diseases and Hepatology from 1999 to 2001, composed the study group. Liver biopsy specimens were used for immunohistochemical assessment of expression of Ki-67, transforming growth factor beta1 (TGF-beta1) and B-cell lymphoma-leukemia-2 (Bcl-2). Grade of liver inflammation and stage of fibrosis were evaluated according to the Scheuer scale.

RESULTS

Expression of Ki-67 in hepatocytes was most intensive in patients with grade 2 and 3 inflammation. The expression in patients with grade 4 inflammation was low. The expression of Ki-67 in lymphocytes was most intensive in patients with grade 2 inflammation. Expression of TGF-beta1 in hepatocytes reached a maximum in patients with grade 2 or 3 inflammation and dropped in patients with grade 4 inflammation. There was a statistically significant correlation between stage of fibrosis and expression of TGF-beta1 in liver stromal cells. A very strong correlation was found between the expression of Bcl-2 in bile ductules epithelium and the grade of inflammation (P = 0.006). The expression of Bcl-2 in hepatocytes was observed only in patients with very intense liver inflammation (grade 3) and in patients with stage 3 or 4 fibrosis.

CONCLUSION

Processes of proliferation, fibrosis and apoptosis are not directly correlated to progression of liver disease. Expression of studied markers can be used for analysis of dynamics of these processes.

Inhibition effect of Chinese herbal medicine on transcription of hepatitis C virus structural gene in vitro

AIM: To investigate the inhibitory effect of Chinese herbal medicine on the transcription of hepatitis C virus (HCV) structural gene in Hela D cells.

METHODS: Hela cell line was transfected with recombinant pBK-CMV-HCV containing HCV structural gene by Lipofec-tamine. RT-nested-PCR and Western blot assay were used to testify the HCV gene expression in Hela cells. The Hela cells expressing HCV structural protein were named Hela D cells. Prescriptions of Xiao chaihu Decoction (XCHD), Fufang Huangqi (FFHQ) and Bingganling (BGL) were respectively added to Hela D cells in various concentrations. Semi-quantitative RT-nested-PCR product analysis was performed according to the fluorescent density between HCV DNA band and GAPDH DNA band in gel electrophoresis after screened.

RESULTS: Recombinant pBK-CMV-HCV could correctly express the HCV structural gene in Hela D cells. After co-culture of Hela D cells with three prescriptional different concentrations for 48 h respectively, the transcription of HCV gene decreased with increasing of the concentration of each prescription. The lightness ratio of HCV product bands to GAPDH product bands was 0.24, 0.10 and 0.12 in Hela D cells incubated with 0.1 g/mL of XCHD, FFHQ and BGL respectively and the lightness ratio HCV product bands to GAPDH product bands was 0.75, 0.67 and 0.61 respectively in the control cells.

CONCLUSION: The prescriptions of XCHD, FFHQ and BGL partly inhibit the transcription of HCV structural gene in Hela D cells.