scholarly journals Hepatitis B Virus Pre-S Mutants as Biomarkers and Targets for the Development and Recurrence of Hepatocellular Carcinoma

Viruses ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 945 ◽  
Author(s):  
Chiao-Fang Teng ◽  
Han-Chieh Wu ◽  
Ih-Jen Su ◽  
Long-Bin Jeng

Chronic hepatitis B virus (HBV) infection is a major risk factor for the development of hepatocellular carcinoma (HCC), the leading cause of cancer-related death worldwide. Despite progress in the prevention and therapy of HCC, high incidence and recurrence rates of HCC remain big threats, resulting in poor patient survival. Effective biomarkers and targets of HCC are therefore urgently needed for better management and to improve patient outcomes. Pre-S mutants have been well demonstrated as HBV oncoproteins that play important roles in HCC development through activation of multiple oncogenic signal pathways in hepatocytes, in vitro and in vivo. The presence of pre-S mutants in patients with chronic HBV infection and HBV-related HCC has been associated with a significantly higher risk of HCC development and recurrence after curative surgical resection, respectively. In this review, we summarize the roles of pre-S mutants as biomarkers for predicting HBV-related HCC development and recurrence, and highlight the pre-S mutants-activated oncogenic signal pathways as potential targets for preventing HBV-related HCC development.

2012 ◽  
Vol 18 (4) ◽  
pp. 378-387 ◽  
Author(s):  
Xinghui Zhao ◽  
Zhanzhong Zhao ◽  
Junwei Guo ◽  
Peitang Huang ◽  
Xudong Zhu ◽  
...  

Chronic hepatitis B virus (HBV) infection is an independent risk factor for the development of hepatocellular carcinoma (HCC). The HBV HBx gene is frequently identified as an integrant in the chromosomal DNA of patients with HCC. HBx encodes the X protein (HBx), a putative viral oncoprotein that affects transcriptional regulation of several cellular genes. Therefore, HBx may be an ideal target to impede the progression of HBV infection–related HCC. In this study, integrated HBx was transcriptionally downregulated using an artificial transcription factor (ATF). Two three-fingered Cys2-His2 zinc finger (ZF) motifs that specifically recognized two 9-bp DNA sequences regulating HBx expression were identified from a phage-display library. The ZF domains were linked into a six-fingered protein that specified an 18-bp DNA target in the Enhancer I region upstream of HBx. This DNA-binding domain was fused with a Krüppel-associated box (KRAB) transcriptional repression domain to produce an ATF designed to downregulate HBx integrated into the Hep3B HCC cell line. The ATF significantly repressed HBx in a luciferase reporter assay. Stably expressing the ATF in Hep3B cells resulted in significant growth arrest, whereas stably expressing the ATF in an HCC cell line lacking integrated HBx (HepG2) had virtually no effect. The targeted downregulation of integrated HBx is a promising novel approach to inhibiting the progression of HBV infection–related HCC.


2017 ◽  
Author(s):  
◽  
Andrew Douglas Huber

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] Chronic hepatitis B virus (HBV) infection leads to liver disease, cirrhosis, and hepatocellular carcinoma. Globally, an estimated 50% of all hepatocellular carcinoma cases are linked to chronic HBV infection. More than 240 million people are chronically infected, and there are 0.5-1 million deaths per year due to HBVrelated liver conditions. HBV treatment options rarely cure infections and are associated with adverse side effects that often outweigh the potential benefits of treatment. New treatments, therefore, are highly desired for HBV therapy. Towards this goal, we have developed novel compounds targeting two viral targets and assessed the mechanisms of action by which these compounds act. We have developed systems for the discovery and evaluation of compounds that inhibit 2 distinct steps in the HBV life cycle. Using these systems, we have developed potent inhibitors of HBV replication that have potential to become clinically used HBV drugs. Furthermore, we have used our methods to evaluate which properties of these compounds are likely to result in better viral inhibition. The work described in this thesis has led to at least 2 new compound groups for potential use as HBV antivirals and provides insight into mechanisms by which potent antivirals can be achieved.


2017 ◽  
Vol 26 (3) ◽  
pp. 429-438 ◽  
Author(s):  
Chiao-Fang Teng ◽  
Han-Chieh Wu ◽  
Woei-Cherng Shyu ◽  
Long-Bin Jeng ◽  
Ih-Jen Su

Chronic hepatitis B virus (HBV) infection is a major risk factor for hepatocellular carcinoma (HCC). Pre-S2 mutant represents an HBV oncoprotein that is accumulated in the endoplasmic reticulum (ER) and manifests as type II ground glass hepatocytes (GGHs). Pre-S2 mutant can induce ER stress and initiate multiple ER stress-dependent or -independent cellular signal pathways, leading to growth advantage of type II GGH. Importantly, the mammalian target of rapamycin (mTOR) signal pathways are consistently activated throughout the liver tumorigenesis in pre-S2 mutant transgenic mice and in human HCC tissues, leading to hepatocyte proliferation, metabolic disorders, and HCC tumorigenesis. In this review, we summarize the pre-S2 mutant-induced mTOR signal pathways and its implications in HBV-related HCC tumorigenesis. Clinically, the presence of pre-S2 mutant exhibits a high resistance to antiviral treatment and carries a high risk of HCC development in patients with chronic HBV infection. Targeting at pre-S2 mutant-induced mTOR signal pathways may thus provide potential strategies for the prevention or therapy of HBV-associated HCC.


1996 ◽  
Vol 40 (5) ◽  
pp. 1180-1185 ◽  
Author(s):  
G Civitico ◽  
T Shaw ◽  
S Locarnini

Safe and effective treatments for chronic hepatitis B virus (HBV) infection have yet to be developed. Both ganciclovir (9-[1,3-dihydroxy-2-propoxymethyl]guanine) and foscarnet (trisodium phosphonoformate hexahydrate) are potent inhibitors of hepadnavirus replication when used individually in vitro and in vivo. However, the clinical usefulness of each drug is reduced by dose-limiting toxicity, especially during long-term monotherapy. Here we demonstrate additive inhibition of duck HBV DNA replication in cultures of primary duck hepatocytes congenitally infected with duck HBV by combinations of ganciclovir and foscarnet at low, clinically achievable concentrations. These results suggest that the effects of ganciclovir and foscarnet against HBV may be additive in vivo.


2021 ◽  
Author(s):  
Ming V. Lin ◽  
April Wall

Chronic hepatitis B virus (HBV) infection is a major health burden worldwide, with approximately 257 million people with chronic infection. HBV is a small partially double-stranded DNA virus that replicates within the nucleus of the hepatocyte and commonly leads to chronic infection. Chronic HBV infection can cause cirrhosis, hepatocellular carcinoma, and extrahepatic manifestations such as glomerulonephritis or vasculitis. The latter is due to deposition of circulating immune complex in the different tissues. The natural history of HBV infection can be conceptualized as a spectrum encompassing different phases, including immune tolerance, immune clearance, inactive carrier, and reactivation and resolution. The diagnosis of the different phases of chronic HBV infection relies on various HBV serologies, liver enzyme levels, and histology findings. There are currently eight therapies approved for the treatment of HBV. Tenofovir alafenamide was the most recently approved therapy with a better side effect profile compared with tenofovir disoproxil fumarate. With the recent advances in the basic research in hepatitis B, new treatment options may become available in the near-future. This review contains 9 figures, 11 tables and 80 references Key words: cirrhosis, entecavir, Hepadnaviridae, hepatitis B virus, hepatocellular carcinoma, precore mutation, tenofovir


2021 ◽  
Author(s):  
Ming V. Lin ◽  
April Wall

Chronic hepatitis B virus (HBV) infection is a major health burden worldwide, with approximately 257 million people with chronic infection. HBV is a small partially double-stranded DNA virus that replicates within the nucleus of the hepatocyte and commonly leads to chronic infection. Chronic HBV infection can cause cirrhosis, hepatocellular carcinoma, and extrahepatic manifestations such as glomerulonephritis or vasculitis. The latter is due to deposition of circulating immune complex in the different tissues. The natural history of HBV infection can be conceptualized as a spectrum encompassing different phases, including immune tolerance, immune clearance, inactive carrier, and reactivation and resolution. The diagnosis of the different phases of chronic HBV infection relies on various HBV serologies, liver enzyme levels, and histology findings. There are currently eight therapies approved for the treatment of HBV. Tenofovir alafenamide was the most recently approved therapy with a better side effect profile compared with tenofovir disoproxil fumarate. With the recent advances in the basic research in hepatitis B, new treatment options may become available in the near-future. This review contains 9 figures, 11 tables and 80 references Key words: cirrhosis, entecavir, Hepadnaviridae, hepatitis B virus, hepatocellular carcinoma, precore mutation, tenofovir


2012 ◽  
Vol 56 (12) ◽  
pp. 6186-6191 ◽  
Author(s):  
Raymond F. Schinazi ◽  
Leda Bassit ◽  
Marcia M. Clayton ◽  
Bill Sun ◽  
James J. Kohler ◽  
...  

ABSTRACTNext-generation therapies for chronic hepatitis B virus (HBV) infection will involve combinations of established and/or experimental drugs. The current study investigated thein vitroandin vivoefficacy of tenofovir disoproxil fumarate (TDF) and/or emtricitabine [(−)-FTC] alone and in combination therapy for HBV infection utilizing the HepAD38 system (human hepatoblastoma cells transfected with HBV). Cellular pharmacology studies demonstrated increased levels of (−)-FTC triphosphate with coincubation of increasing concentrations of TDF, while (−)-FTC had no effect on intracellular tenofovir (TFV) diphosphate levels. Quantification of extracellular HBV by real-time PCR from hepatocytes demonstrated the anti-HBV activity with TDF, (−)-FTC, and their combination. Combination of (−)-FTC with TDF or TFV (ratio, 1:1) had a weighted average combination index of 0.7 for both combination sets, indicating synergistic antiviral effects. No cytotoxic effects were observed with any regimens. Using anin vivomurine model which develops robust HBV viremia in nude mice subcutaneously injected with HepAD38 cells, TDF (33 to 300 mg/kg of body weight/day) suppressed virus replication for up to 10 days posttreatment. At 300 mg/kg/day, (−)-FTC strongly suppressed virus titers to up to 14 days posttreatment. Combination therapy (33 mg/kg/day each drug) sustained suppression of virus titer/ml serum (<1 log10unit from pretreatment levels) at 14 days posttreatment, while single-drug treatments yielded virus titers 1.5 to 2 log units above the initial virus titers. There was no difference in mean alanine aminotransferase values or mean wet tumor weights for any of the groups, suggesting a lack of drug toxicity. TDF–(−)-FTC combination therapy provides more effective HBV suppression than therapy with each drug alone.


2000 ◽  
Vol 44 (3) ◽  
pp. 551-560 ◽  
Author(s):  
Danni Colledge ◽  
Gilda Civitico ◽  
Stephen Locarnini ◽  
Tim Shaw

ABSTRACT Penciclovir {9-[2-hydroxy-1-(hydroxymethyl)-ethoxymethyl]guanine [PCV]}, lamivudine ([−]-β-l-2′,3′-dideoxy-3′-thiacytidine [3TC]), and adefovir (9-[2-phosphonylmethoxyethyl]-adenine [PMEA]) are potent inhibitors of hepatitis B virus (HBV) replication. Lamivudine has recently received approval for clinical use against chronic human HBV infection, and both PCV and PMEA have undergone clinical trials against HBV in their respective prodrug forms {famciclovir and adefovir dipivoxil [bis-(POM)-PMEA]}. Since multidrug combinations are likely to be used to control HBV infection, investigation of potential interactions between PCV, 3TC, and PMEA is important. Primary duck hepatocyte cultures which were either acutely or congenitally infected with the duck hepatitis B virus (DHBV) were used to investigate in vitro interactions between PCV, 3TC, and PMEA. Here we show that the anti-DHBV effects of all the combinations containing PCV, 3TC, and PMEA are greater than that of each of the individual components and that their combined activities are approximately additive or synergistic. These results may underestimate the potential in vivo usefulness of PMEA-containing combinations, since there is evidence that PMEA has immunomodulatory activity and, at least in the duck model of chronic HBV infection, is capable of inhibiting DHBV replication in cells other than hepatocytes, the latter being unaffected by treatment with either PCV or 3TC. Further investigation of the antiviral activities of these drug combinations is therefore required, particularly since each of the component drugs is already in clinical use.


Sign in / Sign up

Export Citation Format

Share Document