Pathogenesis and prevention of hepatitis C virus-induced hepatocellular carcinoma

Discovery of Hepatitis C Virus: 2020 Nobel Prize in Medicine

Hepatitis C virus (HCV) accounts for hepatitis, cirrhosis, hepatocellular carcinoma, and liver transplantation. Every year, millions of people develop chronic liver diseases. This article provides novel insights into the major breakthroughs in the discovery of hepatitis C virus. 2020 Nobel Prize in Medicine was awarded to Michael Houghton, Harvey Alter, and Charles Rice for their outstanding contribution in the discovery of HCV. Also, this article deals with current findings, challenges, and future prospects in the diagnosis of HCV infection. DAA, along with protease inhibitors, is found to have higher SVR and is a promising drug to treat HCV infection. However, with regard to the emergence of resistance to DAAs, CRISPR-Cas can be the future technique in preventing resistance. Although the current knowledge of molecular mechanisms associated with HCV infection is insufficient, the better understanding of it provides better hope in the treatment of HCV.

Lymphoma

A cancer causing infection on lymphocytes.

Fulminant hepatitis

A decrease in the size of the liver accompanied even by the death of liver parenchyma with the onset of infection with hepatitis virus.

Transfection

The process of introducing nucleic acids into eukaryotic cells without using viral methods.

Huh-7 cells

A type of liver cells grown in the laboratory for research purposes.

Immunoscreening

A biomedical method that helps to detect a protein produced from a cloned gene after it undergoes transcription, followed by the translation process within the cell.

cDNA library

A group of only the genes that are encoded into proteins by an organism.

Sustained virologic response

Absence of any evidence of the presence of HCV in the blood of patients with chronic HCV infection after undergoing antiviral treatment.

Pegylated interferon

A covalent conjugate of recombinant interferon and polyethylene glycol, used as an antiviral and antineoplastic agent.

Immunoelectron microscopy

A technique to localize ultrastructure antigens or antibodies in cells or tissues for the diagnosis of viral infections.

Stellate cells

A major type of liver cell involved in liver cirrhosis.

Hepatitis C virus (HCV) accounts for hepatitis, liver cirrhosis, hepatocellular carcinoma, and liver transplantation. This virus is a single-stranded RNA virus that belongs to the Flaviviridae family. According to the WHO, about 71 million people have chronic HCV infections around the globe in 2020, and hence, it is a plague of humankind. The credit of discovery of HCV goes to Michael Houghton, Harvey Alter, and Charles Rice for which they are awarded 2020 Nobel Prize in Medicine. Their contribution has given better hope to mankind to cure HCV for the first time in the history. With the use of pegylated interferon and ribavirin jointly, higher SVR has been found comparatively, even in patients with chronic liver diseases. However, due to excessive pain tolerated by patients, interferon (IFN)-based therapy is rapidly being replaced with IFN-free DAA regimens. With the onset of resistance to DAA drugs, CRISPR-Cas system can be used to modify the viral genome to impair their ability to develop resistance.

How to cite this article: Laugi H. Discovery of Hepatitis C Virus: 2020 Nobel Prize in Medicine. Euroasian J Hepato-Gastroenterol 2020;10(2): 105–108.

Risk Factors Contributing to the Occurrence and Recurrence of Hepatocellular Carcinoma in Hepatitis C Virus Patients Treated with Direct-Acting Antivirals

Although hepatitis C virus (HCV) RNA may be eliminated from blood circulation by direct-acting antivirals (DAA) therapy as assessed by real-time polymerase chain reaction (PCR), HCV RNA can still be present in liver tissue, and this is known as occult HCV. There has been a lot of controversy surrounding the recurrence of hepatocellular carcinoma (HCC) after DAA treatment of hepatic cells infected with chronic HCV. One of the main risk factors that leads to de novo HCC is the chronicity of HCV in hepatic cells. There are many studies regarding the progression of HCV-infected hepatic cells to HCC. However, there is a lack of research on the different molecular mechanisms that lead to the progression of chronic HCV infection to HCC, as well as on the effect of HCV on the alteration of DNA ploidy, which eventually leads to a recurrence of HCC after DAA treatment. In this review article, we will address some risk factors that could lead to the development/recurrence of HCC after treatment of HCV with DAA therapy, such as the role of liver cirrhosis, the alteration of DNA ploidy, the reactivation of hepatitis B virus (HBV), the role of cytokines and the alteration of the immune system, concomitant non- alcoholic fatty liver disease (NAFLD), obesity, alcohol consumption and also occult HCV infection/co-infection. Clinicians should be cautious considering that full eradication of hepatocarcinogenesis cannot be successfully accomplished by anti-HCV treatment alone.

Risk Factors Contributing to the Occurrence and Recurrence of Hepatocellular Carcinoma in Hepatitis C Virus Patients Treated with Direct-Acting Antivirals

Although hepatitis C virus (HCV) RNA may be eliminated from blood circulation by direct-acting antivirals (DAA) therapy as assessed by real-time polymerase chain reaction (PCR), HCV RNA can still be present in liver tissue, and this is known as occult HCV. There has been a lot of controversy surrounding the recurrence of hepatocellular carcinoma (HCC) after DAA treatment of hepatic cells infected with chronic HCV. One of the main risk factors that leads to de novo HCC is the chronicity of HCV in hepatic cells. There are many studies regarding the progression of HCV-infected hepatic cells to HCC. However, there is a lack of research on the different molecular mechanisms that lead to the progression of chronic HCV infection to HCC, as well as on the effect of HCV on the alteration of DNA ploidy, which eventually leads to a recurrence of HCC after DAA treatment. In this review article, we will address some risk factors that could lead to the development/recurrence of HCC after treatment of HCV with DAA therapy, such as the role of liver cirrhosis, the alteration of DNA ploidy, the reactivation of hepatitis B virus (HBV), the role of cytokines and the alteration of the immune system, concomitant non- alcoholic fatty liver disease (NAFLD), obesity, alcohol consumption and also occult HCV infection/co-infection. Clinicians should be cautious considering that full eradication of hepatocarcinogenesis cannot be successfully accomplished by anti-HCV treatment alone.

Telomerase reverse transcriptase (TERT) promoter mutation correlated with intratumoral heterogeneity in hepatocellular carcinoma

Telomerase reverse transcriptase (TERT) promoter mutations are frequently observed in hepatocellular carcinoma (HCC); however, the impact of TERT promoter mutations (TPMs) on clinical features and morphological patterns in HCC remains unresolved. Using DNA extracted from 97 HCCs, correlations between TPM status and both the clinical features of HCC and the immunohistochemically-based subgroups were evaluated. Morphological tumor patterns were semi-quantitatively analyzed using hematoxylin and eosin-stained slides of the whole tumor cross-sectional area. The percentages of tumor area occupied by early, well, moderate and poor histological patterns were calculated as a homogeneity index. TPMs were observed in 53 of 97 (55%) HCCs and were significantly associated with older age (P = 0.018) and HCV-related background (P = 0.048). The biliary/stem cell marker-positive subgroup was less likely to have TPMs (29%) compared to the Wnt/β-catenin signaling marker-positive subgroup (60%). In contrast to TPM-negative HCCs, TPM-positive HCCs clearly exhibited intratumoral morphological heterogeneity (0.800 ± 0.117 vs 0.927 ± 0.096, P < 0.0001), characterized by two or more heterogeneous histological patterns (P < 0.0001) and had more well or early differentiated histological patterns (P = 0.024). Our findings showed that intratumoral heterogeneity was strongly related to TPM-positive HCCs, which established novel roles of TPMs, and may improve our understanding particularly about HCC development and diagnosis.

Prognostic value of combined preoperative gamma-glutamyl transpeptidase to platelet ratio and fibrinogen in patients with HBV-related hepatocellular carcinoma after hepatectomy

The gamma-glutamyl transpeptidase to platelet ratio (GPR) has been reported as a non-invasive parameter for evaluating hepatic fibrosis and cirrhosis. However, only a few of studies investigated the relationship between GPR and liver cancer. Here, we sought to clarify the prognostic value of GPR as well as its combination with fibrinogen in patients with HBV-related hepatocellular carcinoma (HCC). We performed a retrospective study using data collected from 302 HCC patients, and evaluated the association between GPR, fibrinogen and clinicopathological characteristics using the chi-square test. Additionally, we assessed disease-free survival (DFS) and overall survival (OS) using the Kaplan-Meier method and log-rank test, then performed univariate and multivariate COX analyses to identify the prognostic factors. The prognostic performance of combined GPR and fibrinogen was evaluated by the receiver operating characteristic curve analysis. Results showed that GPR was associated with gender, history of smoking and drinking, cirrhosis, antiviral treatments, tumor number, and Child-Pugh grade. Univariate analysis revealed a significant correlation between tumor diameter, vascular invasion, BCLC stage, alpha-fetal protein, GPR, fibrinogen, and NLR with both DFS and OS in HCC patients. Only GPR and fibrinogen were found to be independently associated with both DFS and OS according to multivariate analysis. Furthermore, predictive capacity was enhanced by combining GPR with fibrinogen owing to a larger area under the curve than other indexes or models. Overall, preoperative GPR could be an effective non-invasive predictor for prognosis of HBV-related HCC patients, and a combination of GPR and fibrinogen improved the prognostic performance.

IL-10 Polymorphisms and Haplotypes Predict Susceptibility to Hepatocellular Carcinoma Occurrence in Patients with Hepatitis C Virus Infection from Northeast India

Chronic hepatitis C virus (HCV) infection leads to variable outcomes, ranging from prolonged slow hepatic damage leading to cirrhosis, and hepatocellular carcinoma (HCC). Polymorphism in cytokines IL-10 and IL-12 that impact the immune response to HCV infection may play a role in determining this outcome. This study was aimed to determine if polymorphisms in IL-10 and IL-12B contribute to HCV susceptibility and the risk of developing HCC in patients from Northeast India. IL-10 - 1082, -819, -592 polymorphisms and IL-12B -1188 polymorphisms were genotyped by polymerase chain reaction-restriction fragment length polymorphism in a total of 266 HCV-infected patients and 100 age- and sex-matched controls. In the HCV-infected subjects, 110 patients had chronic hepatitis C (CHC), 96 with liver cirrhosis, and 60 with HCC. Serum levels of IL-10 were also measured and correlated with disease severity. Haplotype analysis for IL-10 polymorphisms was carried out. Statistical data were analyzed using SPSS ver. 22.0. The frequency of IL-10 - 592 AA genotype/A allele was significantly higher in HCC patients than in CHC patients. The intermediate IL-10-producing ACC haplotype was significantly more frequent in HCC and cirrhotic patients than in CHC patients. No significant association was found for IL-10 - 819, -592 and IL-12B -1188 polymorphisms with the susceptibility to HCV infection or occurrence of HCC in HCV-infected patients. IL-10 - 592 CA polymorphism and IL-10 ACC haplotype are significant biomarkers of HCC in HCV-infected patients from Northeast India. Higher serum levels of IL-10 were also linked to higher disease severity.

The landscape of gene mutations in cirrhosis and hepatocellular carcinoma

Chronic liver disease and primary liver cancer are a massive global problem, with a future increase in incidences predicted. The most prevalent form of primary liver cancer, hepatocellular carcinoma, occurs after years of chronic liver disease. Mutations in the genome are a causative and defining feature of all cancers. Chronic liver disease, mostly at the cirrhotic stage, causes the accumulation of progressive mutations which can drive cancer development. Within the liver, a Darwinian process selects out dominant clones with selected driver mutations but also leaves a trail of passenger mutations which can be used to track the evolution of a tumour. Understanding what causes specific mutations and how they combine with one another to form cancer is a question at the heart of understanding, preventing and tackling liver cancer. Herein, we review the landscape of gene mutations in cirrhosis, especially those paving the way toward hepatocellular carcinoma development, that have been characterised by recent studies capitalising on technological advances in genomic sequencing. With these insights, we are beginning to understand how cancers form in the liver, particularly on the background of chronic liver disease. This knowledge may soon lead to breakthroughs in the way we detect, diagnose and treat this devastating disease.

Hepatitis C Virus and Hepatocellular Carcinoma: When the Host Loses Its Grip

Chronic infection with hepatitis C virus (HCV) is a major cause of hepatocellular carcinoma (HCC). Novel treatments with direct-acting antivirals achieve high rates of sustained virologic response; however, the HCC risk remains elevated in cured patients, especially those with advanced liver disease. Long-term HCV infection causes a persistent and accumulating damage of the liver due to a combination of direct and indirect pro-oncogenic mechanisms. This review describes the processes involved in virus-induced disease progression by viral proteins, derailed signaling, immunity, and persistent epigenetic deregulation, which may be instrumental to develop urgently needed prognostic biomarkers and as targets for novel chemopreventive therapies.

Sofosbuvir Activates EGFR-Dependent Pathways in Hepatoma Cells with Implications for Liver-Related Pathological Processes

Direct acting antivirals (DAAs) revolutionized the therapy of chronic hepatitis C infection. However, unexpected high recurrence rates of hepatocellular carcinoma (HCC) after DAA treatment became an issue in patients with advanced cirrhosis and fibrosis. In this study, we aimed to investigate an impact of DAA treatment on the molecular changes related to HCC development and progression in hepatoma cell lines and primary human hepatocytes. We found that treatment with sofosbuvir (SOF), a backbone of DAA therapy, caused an increase in EGFR expression and phosphorylation. As a result, enhanced translocation of EGFR into the nucleus and transactivation of factors associated with cell cycle progression, B-MYB and Cyclin D1, was detected. Serine/threonine kinase profiling identified additional pathways, especially the MAPK pathway, also activated during SOF treatment. Importantly, the blocking of EGFR kinase activity by erlotinib during SOF treatment prevented all downstream events. Altogether, our findings suggest that SOF may have an impact on pathological processes in the liver via the induction of EGFR signaling. Notably, zidovudine, another nucleoside analogue, exerted a similar cell phenotype, suggesting that the observed effects may be induced by additional members of this drug class.

Decreased risk of hepatocellular carcinoma recurrence with direct-acting antivirals compared with no treatment for hepatitis C: a meta-analysis

Background

Studies investigating the association between direct-acting antivirals (DAAs) and the recurrence of hepatocellular carcinoma (HCC) related to hepatitis C (HCV) have yielded conflicting results. The objective of this meta-analysis was to define the short- and long-term recurrence rates of HCC after DAA treatment.

Methods

A search of multiple databases was performed, including Scopus, Cochrane, MEDLINE/PubMed and abstracts from gastroenterology meetings. Only studies reporting the recurrence of HCC in patients receiving DAA treatment, compared to HCV controls without DAA treatment, were evaluated. A meta-analysis was completed using the Mantel-Haenszel model.

Results

A comprehensive literature search resulted in 32 abstracts and papers. Six papers met our inclusion criteria and were included in the analysis. Follow up ranged from 1.25-4 years. Analysis of these 6 studies found a >60% lower risk of HCC recurrence in patients exposed to DAA compared to controls (odds ratio [OR] 0.36, 95% confidence interval [CI] 0.27-0.47; P<0.001; I²=88%). A sensitivity analysis, which excluded studies showing the lowest recurrence rate to reduce heterogeneity, showed that patients receiving DAA still had a 60% lower risk of developing HCC (OR 0.4, 95%CI 0.26-0.61; P<0.0001; I²=39%) and a 66% lower risk of developing HCC beyond 1 year (OR 0.34, 95%CI 0.22-0.54; P<0.00001; I²=0%) compared to controls.

Conclusions

The use of DAA is associated with a significantly lower risk of HCC development compared to DAA-untreated patients, both overall and beyond 1 year of treatment. Further studies are needed to assess the impact of DAAs on early recurrence.

DNA and RNA sequencing identified a novel oncogene VPS35 in liver hepatocellular carcinoma

Liver hepatocellular carcinoma (LIHC) is the second leading cause of cancer mortality worldwide. Although cancer driver genes identified so far have been considered to be saturated or nearly saturated, challenges remain in discovering novel genes underlying carcinogenesis due to significant tumor heterogeneity. Here, in a small cohort of hepatitis B virus (HBV)-associated LIHC, we investigated the transcriptional patterns of tumor-mutated alleles using both whole-exome and RNA sequencing data. A graph clustering of the transcribed tumor-mutated alleles characterized overlapped functional clusters, and thus prioritized potentially novel oncogenes. We validated the function of the potentially novel oncogenes in vitro and in vivo. We showed that a component of the retromer complex-the vacuolar protein sorting-associated protein 35 (VPS35)-promoted the proliferation of hepatoma cell through the PI3K/AKT signaling pathway. In VPS35-knockout hepatoma cells, a significantly reduced distribution of membrane fibroblast growth factor receptor 3 (FGFR3) demonstrated the effects of VPS35 on sorting and trafficking of transmembrane receptor. This study provides insight into the roles of the retromer complex on carcinogenesis and has important implications for the development of personalized therapeutic strategies for LIHC.

Mechanistic study of interaction between IL-22 and HCV core protein in the development of hepatocellular carcinoma among liver transplant recipients

BACKGROUND

Hepatitis C virus (HCV) infects more than 170 million people worldwide that represents a major threat to global public health. Several viruses including HCV have developed mechanisms against the cellular responses essentially "hijacking" the antiviral responses generated against it. Interleukin 22 activated JAK-STAT pathways are responsible for several functions including liver regeneration, antiviral responses and cell cycle regulation.

OBJECTIVES

Present study aims to un-reveal the speculated role of HCV core protein in perturbing IL-22 mediated JAK-STAT pathway. Principally investigating through interaction with IL-22 and SOCS-3 proteins.

PATIENTS AND METHODOLOGY

Total 36 liver transplant patients were enrolled in the study. Out of which 24 were found HCV + ve. Immunohistochemistry (IHC) based qualitative expression analysis of IL-22, SOCS-3 and HCV core protein was carried out. Microscopy was performed for detection and visualization of immunostained liver tissues and biopsies.

RESULTS

Hepatic expression of IL-22, HCV core protein and SOCS-3 showed that SOCS-3 expression levels were considerably high compared to HCV core and IL-22 protein. IL-22's moderate to high expression was found in 70% of the liver transplant patient sample. Total 87% patients showed moderate to high SOCS-3 expression. However, the overall expression of HCV core was stronger in 87% of cirrhotic patients and 14% in HCC patients. Suggesting the presence of HCV core protein clearly impacted the IL-22 mediated cellular signaling (JAK-STAT pathway leading towards hepatocarcinogenesis.

CONCLUSION

HCV core and IL-22 and SOCS-3 molecules are found to be correlated statistically under this study. Concluded from this study that HCV core protein plays a potential role in diverging the hepatocytes from normal to carcinogenic. One cell signaling path cannot decide, the direct role of a single viral protein in developing viral induced hepatocarcinogenesis. Interpreting the complex network of cell signaling involved in HCC development is impractical to study under single study. That is why step by step unmasking the interactive role of few molecules under single study is the ideal way to resolve the impact of viral proteins on cell signaling. SOCS-3 is mediator for dysregulating IL-22 mediated liver regenerative pathway. Moreover, SOCS-3 and STAT-3 molecules are proposed to be a potential therapeutic target for managing HCC progression.

Metabolism-associated molecular classification of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a disease with unique management complexity because it displays high heterogeneity of molecular phenotypes. We herein aimed to characterize the molecular features of HCC by the development of a classification system that was based on the gene expression profile of metabolic genes. Integrative analysis was performed with a metadata set featuring 371 and 231 HCC human samples from the Cancer Genome Atlas and the International Cancer Genome Consortium, respectively. All samples were linked with clinical information. RNA sequencing data of 2752 previously characterized metabolism-related genes were used for non-negative matrix factorization clustering, and three subclasses of HCC (C1, C2, and C3) were identified. We then analyzed the metadata set for metabolic signatures, prognostic value, transcriptome features, immune infiltration, clinical characteristics, and drug sensitivity of subclasses, and compared the resulting subclasses with previously published classifications. Subclass C1 displayed high metabolic activity, low α-fetoprotein (AFP) expression, and good prognosis. Subclass C2 was associated with low metabolic activities and displayed high expression of immune checkpoint genes, demonstrating drug sensitivity toward cytotoxic T-lymphocyte-associated protein-4 inhibitors and the receptor tyrosine kinase inhibitor cabozantinib. Subclass C3 displayed intermediate metabolic activity, high AFP expression level, and bad prognosis. Finally, a 90-gene classifier was generated to enable HCC classification. This study establishes a new HCC classification based on the gene expression profiles of metabolic genes, thereby furthering the understanding of the genetic diversity of human HCC.

Precision pathology analysis of the development and progression of hepatocellular carcinoma: Implication for precision diagnosis of hepatocellular carcinoma

Outcomes for patients with hepatocellular carcinoma (HCC) remain poor because the condition is often unresponsive to the available treatments. Consequently, the early and precise diagnosis of HCC is crucial to achieve improvements in prognosis. For patients with chronic liver disease, the assessment of liver fibrosis is also important to ascertain both the staging of fibrosis and the risk of HCC occurrence. Early HCC was first described in 1991 in Japan and was defined internationally in 2009. As the concept of early HCC spread, the multistage hepatocarcinogenesis process became accepted. Consequently, improvements in imaging technology made the early diagnosis of HCC possible. At present, the most appropriate therapeutic strategy for HCC is determined using an integrated staging system that assesses the tumor burden, the degree of liver dysfunction and the patient performance status; however, pathological and molecular features are not taken into account. The recent introduction of several new therapeutic agents will change the treatment strategy for HCC. Against this background, HCC subclassification based on tumor cellular and microenvironmental characteristics will become increasingly important. In this review, we give an overview of how pathological analysis contributes to understanding the development and progression of HCC and establishing a precision diagnosis of HCC.

Mesenchymal stromal cells induce inhibitory effects on hepatocellular carcinoma through various signaling pathways

Hepatocellular carcinoma (HCC) is the most prevalent type of malignant liver disease worldwide. Molecular changes in HCC collectively contribute to Wnt/β-catenin, as a tumor proliferative signaling pathway, toll-like receptors (TLRs), nuclear factor-kappa B (NF-κB), as well as the c-Jun NH2-terminal kinase (JNK), predominant signaling pathways linked to the release of tumor-promoting cytokines. It should also be noted that the Hippo signaling pathway plays an important role in organ size control, particularly in promoting tumorigenesis and HCC development. Nowadays, mesenchymal stromal cells (MSCs)-based therapies have been the subject of in vitro, in vivo, and clinical studies for liver such as cirrhosis, liver failure, and HCC. At present, despite the importance of basic molecular pathways of malignancies, limited information has been obtained on this background. Therefore, it can be difficult to determine the true concept of interactions between MSCs and tumor cells. What is known, these cells could migrate toward tumor sites so apply effects via paracrine interaction on HCC cells. For example, one of the inhibitory effects of MSCs is the overexpression of dickkopf-related protein 1 (DKK-1) as an important antagonist of the Wnt signaling pathway. A growing body of research challenging the therapeutic roles of MSCs through the secretion of various trophic factors in HCC. This review illustrates the complex behavior of MSCs and precisely how their inhibitory signals interface with HCC tumor cells.

The influence of direct-acting antivirals in hepatitis C virus related hepatocellular carcinoma after curative treatment

This study was done to elucidate the influence of direct-acting antiviral (DAA) agents on the recurrence of hepatocellular carcinoma (HCC) in patients with hepatitis C virus (HCV)-related HCC (HCV-HCC) after curative therapies. HCV-HCC patients who received curative therapies and obtained a complete response were analyzed. From January 2017 to September 2017, 112 HCV-HCC patients received DAA and obtained a sustained virological response (SVR). From January 2006 to December 2014, another 345 HCV-HCC patients received peg-interferon-based treatment and 118 obtained SVR. From January 2012 to December 2016, 248 HCV-HCC patients had complete HCC response and did not receive antiviral treatment. Patients were divided into DAA, IFN, and Untreated groups based on what antiviral treatment they received. There were 82 patients in the DAA group, 80 patients in the IFN group, and 160 patients in the Untreated group. During the follow-up period, the DAA group had 22 (26.8%) recurrent cases, whereas the IFN group had 46 (56.8%) cases after antiviral treatment. Among the 22 recurrent cases in the DAA group, 19 (86.9%) experienced HCC recurrence during 1 year after DAA initiation. Compared with the IFN group, the DAA group had poorer one-year recurrence-free survival (75.4% vs. 95%, p < 0.001), even after adjustment with propensity score matching (81.4% vs. 93.9%, p = 0.034). However, DAA was an improving factor for HCC recurrence compared with the Untreated group in the multivariate analysis. Among HCV-HCC patients with complete treatment, those with DAA-induced SVR had a higher one-year recurrence rate than those who received IFN-based antiviral therapy, but DAA did not seem to increase HCC recurrence compared to untreated patients.

A Recombinant Hepatitis C Virus Genotype 1a E1/E2 Envelope Glycoprotein Vaccine Elicits Antibodies That Differentially Neutralize Closely Related 2a Strains through Interactions of the N-Terminal Hypervariable Region 1 of E2 with Scavenger Receptor B1

A vaccine is still urgently needed to overcome the hepatitis C virus (HCV) epidemic. It is estimated that 1.75 million new HCV infections occur each year, many of which will go undiagnosed and untreated. Untreated HCV can lead to continued spread of the disease, progressive liver fibrosis, cirrhosis, and eventually, end-stage liver disease and/or hepatocellular carcinoma (HCC). Previously, our 1a E1/E2 glycoprotein vaccine was shown to elicit broadly cross-neutralizing antibodies; however, there remains variation in the effectiveness of these antibodies against different HCV genotypes. In this study, we investigated determinants of differential neutralization sensitivity between two highly related genotype 2a isolates, J6 and JFH-1. Our data indicate that the HVR1 region determines neutralization sensitivity to vaccine antisera through modulation of sensitivity to antibodies and interactions with SR-B1. Our results provide additional insight into optimizing a broadly neutralizing HCV vaccine.

The global health burden for hepatitis C virus (HCV) remains high, despite available effective treatments. To eliminate HCV, a prophylactic vaccine is needed. One major challenge in the development of a vaccine is the genetic diversity of the virus, with 7 major genotypes and many subtypes. A global vaccine must be effective against all HCV genotypes. Our previous data showed that the 1a E1/E2 glycoprotein vaccine component elicits broad cross-neutralizing antibodies in humans and animals. However, some variation is seen in the effectiveness of these antibodies to neutralize different HCV genotypes and isolates. Of interest was the differences in neutralizing activity against two closely related isolates of HCV genotype 2a, the J6 and JFH-1 strains. Using site-directed mutagenesis to generate chimeric viruses between the J6 and JFH-1 strains, we found that variant amino acids within the core E2 glycoprotein domain of these two HCV genotype 2a viruses do not influence isolate-specific neutralization. Further analysis revealed that the N-terminal hypervariable region 1 (HVR1) of the E2 protein determines the sensitivity of isolate-specific neutralization, and the HVR1 of the resistant J6 strain binds scavenger receptor class-B type-1 (SR-B1), while the sensitive JFH-1 strain does not. Our data provide new information on mechanisms of isolate-specific neutralization to facilitate the optimization of a much-needed HCV vaccine.

IMPORTANCE A vaccine is still urgently needed to overcome the hepatitis C virus (HCV) epidemic. It is estimated that 1.75 million new HCV infections occur each year, many of which will go undiagnosed and untreated. Untreated HCV can lead to continued spread of the disease, progressive liver fibrosis, cirrhosis, and eventually, end-stage liver disease and/or hepatocellular carcinoma (HCC). Previously, our 1a E1/E2 glycoprotein vaccine was shown to elicit broadly cross-neutralizing antibodies; however, there remains variation in the effectiveness of these antibodies against different HCV genotypes. In this study, we investigated determinants of differential neutralization sensitivity between two highly related genotype 2a isolates, J6 and JFH-1. Our data indicate that the HVR1 region determines neutralization sensitivity to vaccine antisera through modulation of sensitivity to antibodies and interactions with SR-B1. Our results provide additional insight into optimizing a broadly neutralizing HCV vaccine.

DNA methylation of individual repetitive elements in hepatitis C virus infection-induced hepatocellular carcinoma

Background

The two most common repetitive elements (REs) in humans, long interspersed nuclear element-1 (LINE-1) and Alu element (Alu), have been linked to various cancers. Hepatitis C virus (HCV) may cause hepatocellular carcinoma (HCC) by suppressing host defenses, through DNA methylation that controls the mobilization of REs. We aimed to investigate the role of RE methylation in HCV-induced HCC (HCV-HCC).

Results

We studied methylation of over 30,000 locus-specific REs across the genome in HCC, cirrhotic, and healthy liver tissues obtained by surgical resection. Relative to normal liver tissue, we observed the largest number of differentially methylated REs in HCV-HCC followed by alcohol-induced HCC (EtOH-HCC). After excluding EtOH-HCC-associated RE methylation (FDR < 0.001) and those unable to be validated in The Cancer Genome Atlas (TCGA), we identified 13 hypomethylated REs (11 LINE-1 and 2 Alu) and 2 hypermethylated REs (1 LINE-1 and 1 Alu) in HCV-HCC (FDR < 0.001). A majority of these REs were located in non-coding regions, preferentially enriched with chromatin repressive marks H3K27me3, and positively associated with gene expression (median correlation r = 0.32 across REs). We further constructed an HCV-HCC RE methylation score that distinguished HCV-HCC (lowest score), HCV-cirrhosis, and normal liver (highest score) in a dose-responsive manner (p for trend < 0.001). HCV-cirrhosis had a lower score than EtOH-cirrhosis (p = 0.038) and HCV-HCC had a lower score than EtOH-HCC in TCGA (p = 0.024).

Conclusions

Our findings indicate that HCV infection is associated with loss of DNA methylation in specific REs, which could implicate molecular mechanisms in liver cancer development. If our findings are validated in larger sample sizes, methylation of these REs may be useful as an early detection biomarker for HCV-HCC and/or a target for prevention of HCC in HCV-positive individuals.

Electronic supplementary material

The online version of this article (10.1186/s13148-019-0733-y) contains supplementary material, which is available to authorized users.

Inhibition Mechanisms of Hepatitis C Virus Infection by Caffeic Acid and Tannic Acid

Previously, we reported that coffee extract and its constituents, caffeic acid (CA) and p-coumaric acid, inhibit infection by the hepatitis C virus (HCV). In the present report, we identified another coffee-related compound, tannic acid (TA), which also inhibits HCV infection. We systematically evaluated which steps of the viral lifecycle were affected by CA and TA. TA substantially inhibits HCV RNA replication and egression, while CA does not. The infectivity of the HCV pretreated with CA or TA was almost lost. Cellular attachment of HCV particles and their interaction with apolipoprotein E, which is essential for HCV infectivity, were significantly reduced by CA. These results indicate that CA inhibits HCV entry via its direct effect on viral particles and TA inhibits HCV RNA replication and particle egression as well as entry into host cells. Taken together, our findings may provide insights into CA and TA as potential anti-HCV strategies.

MicroRNA-1181 supports the growth of hepatocellular carcinoma by repressing AXIN1

Micro-RNAs regulate multiple biological behaviors of cancers, making them potential targets of new cancer therapies. MiR-1181 has been demonstrated to perform oncogenic or tumor-suppressing function in a tissue-dependent way, but its role in hepatocellular carcinoma (HCC) was unclear. Here, we showed that miR-1181 was significantly overexpressed in HCC tissues when compared with tumor-adjacent normal ones or normal liver tissues from donated organ, and that inhibition of miR-1181 could repress the growth of HCC cells. Through bioinformatics analysis and luciferase reporter assays, we found that axis inhibition protein 1 (AXIN1) was a direct target of miR-1181, and the expression of AXIN1 showed a negative correlation with that of miR-1181 in HCC. Therefore, these data indicated an oncogenic function of miRNA-1181 in the development of HCC and a potential target for the clinical treatment of HCC.

The circadian clock and liver function in health and disease

Each day, all organisms are subjected to changes in light intensity because of the Earth's rotation around its own axis. To anticipate this geo-physical variability, and to appropriately respond biochemically, most species, including mammals, have evolved an approximate 24-hour endogenous timing mechanism known as the circadian clock (CC). The 'clock' is self-sustained, cell autonomous and present in every cell type. At the core of the clock resides the CC-oscillator, an exquisitely crafted transcriptional-translational feedback system. Remarkably, components of the CC-oscillator not only maintain daily rhythmicity of their own synthesis, but also generate temporal variability in the expression levels of numerous target genes through transcriptional, post-transcriptional and post-translational mechanisms, thus, ensuring proper chronological coordination in the functioning of cells, tissues and organs, including the liver. Indeed, a variety of physiologically critical hepatic functions and cellular processes are CC-controlled. Thus, it is not surprising that modern lifestyle factors (e.g. travel and jet lag, night and rotating shift work), which force 'circadian misalignment', have emerged as major contributors to global health problems including obesity, non-alcoholic fatty liver disease and steatohepatitis. Herein, we provide an overview of the CC-dependent pathways which play critical roles in mediating several hepatic functions under physiological conditions, and whose deregulation is implicated in chronic liver diseases including non-alcoholic steatohepatitis and alcohol-related liver disease.

A method for detecting hepatitis C envelope specific memory B cells from multiple genotypes using cocktail E2 tetramers

Hepatitis C (HCV) is a rapidly mutating RNA virus, with a strong propensity to cause chronic infection and progressive liver disease. Recent evidence has shown that early appearance of neutralizing antibodies in primary infection is associated with clearance. Little is known about the characteristics of HCV-specific B cells and their correlation with outcomes in primary infection, as there is a lack of sensitive tools for HCV-specific B cells which are present at very low frequency. We describe the development and optimisation of tetramer staining for flow cytometric detection of HCV-specific B cells using a cocktail of two recombinant HCV Envelope-2 (rE2) glycoproteins (from genotype 1a and 3a; Gt1a and Gt3a) and streptavidin dyes. The optimal weight to weight (w/w) ratio of streptavidin-phycoerythrin (PE) and rE2 proteins were determined for sensitive detection using HCV E2-specific hybridoma cell lines and peripheral blood mononuclear cells (PBMC) from HCV-infected individuals. In a cross-sectional set of PBMC samples collected from 33 subjects with either chronic infection or previous clearance, HCV E2-specific B cells (CD19⁺CD20⁺CD10^-IgD^-tetramer⁺) were detected in 29 subjects (87.8%), with a mean frequency of 0.45% (0.012-2.20%). To validate the specificity of tetramer staining, 367 HCV E2-specific B cells were single cell sorted from 9 PBMC samples before monoclonal antibodies (mAbs) were synthesised, with 87.5% being reactive to E2 via ELISA. Of these mAbs, 284 and 246 clones were reactive to either Gt1a or Gt3a E2 proteins, respectively. This is a sensitive and robust method for future studies investigating B cell responses against the HCV Envelope protein.

Real-world safety and efficacy of paritaprevir/ritonavir/ombitasvir plus dasabuvir ± ribavirin in patients with hepatitis C virus genotype 1 and advanced hepatic fibrosis or compensated cirrhosis: a multicenter pooled analysis

Paritaprevir/ritonavir, ombitasvir, and dasabuvir (PrOD) with or without ribavirin shows favorable results in hepatitis C virus genotype 1 (HCV-1) patients in terms of safety and efficacy, but real-world data remain limited for those with advanced hepatic fibrosis (fibrosis 3, F3) or compensated cirrhosis (F4). A total of 941 patients treated in four hospitals (the Keelung, the Linkuo, the Chiayi and the Kaohsiung Chang Gung Memorial Hospital) through a nationwide government-funded program in Taiwan were enrolled. Patients with HCV and advanced hepatic fibrosis or compensated cirrhosis received 12 weeks of PrOD in HCV-1b and 12 or 24 weeks of PrOD plus ribavirin therapy in HCV-1a without or with cirrhosis. Advanced hepatic fibrosis or compensated cirrhosis was confirmed by either ultrasonography, fibrosis index based on 4 factors (FIB-4) test, or transient elastography/acoustic radiation force impulse (ARFI). The safety and efficacy (sustained virologic response 12 weeks off therapy, SVR₁₂) were evaluated. An SVR₁₂ was achieved in 887 of 898 (98.8%) patients based on the per-protocol analysis (subjects receiving ≥1 dose of any study medication and HCV RNA data available at post-treatment week 12). Child-Pugh A6 (odds ratio: 0.168; 95% confidence interval (CI): 0.043–0.659, p = 0.011) was the only significant factor of poor SVR₁₂. Fifty-four (5.7%) patients were withdrawn early from the treatment because of hepatic decompensation (n = 18, 1.9%) and other adverse reactions. Multivariate analyses identified old age (odds ratio: 1.062; 95% CI: 1.008–1.119, p = 0.024) and Child-Pugh A6 (odds ratio: 4.957; 95% CI: 1.691–14.528, p = 0.004) were significantly associated with hepatic decompensation. In conclusion, this large real-world cohort proved PrOD with or without ribavirin to be highly effective in chronic hepatitis C patients with advanced hepatic fibrosis or compensated cirrhosis. However, Child-Pugh A6 should be an exclusion criterion for first-line treatment in these patients.

Homeobox Genes and Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the sixth most common type of cancer, and is the third leading cause of cancer-related deaths each year. It involves a multi-step progression and is strongly associated with chronic inflammation induced by the intake of environmental toxins and/or viral infections (i.e., hepatitis B and C viruses). Although several genetic dysregulations are considered to be involved in disease progression, the detailed regulatory mechanisms are not well defined. Homeobox genes that encode transcription factors with homeodomains control cell growth, differentiation, and morphogenesis in embryonic development. Recently, more aberrant expressions of Homeobox genes were found in a wide variety of human cancer, including HCC. In this review, we summarize the currently available evidence related to the role of Homeobox genes in the development of HCC. The objective is to determine the roles of this conserved transcription factor family and its potential use as a therapeutic target in future investigations.

Lysyl oxidase induces epithelial-mesenchymal transition and predicts intrahepatic metastasis of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) has high recurrence rates even after curative hepatectomy. Drug therapy for recurrence of HCC is still limited; therefore, identifying new therapeutic targets is urgently needed. We searched for genes that would predict HCC recurrence from intrahepatic metastasis in an exhaustive DNA microarray database by searching genes associated with high early recurrence rate and having higher expression in the tumor area compared to background liver. We detected lysyl oxidase (LOX) and validated the clinical significance of LOX in 358 patients who underwent hepatectomy. Expression of LOX was evaluated by qRT‐ PCR, and immunohistochemical (IHC) staining. High LOX expression group had a significantly higher recurrence rate than the low LOX expression group (2‐year recurrence rate was 64.0% vs 24.2%, P < .0001 for IHC) and poorer survival rate (5‐year rate was 60.1% vs 86.2%, P < .0001 for IHC). Multivariate analysis showed that high LOX expression was an independent risk factor for early recurrence (IHC: HR, 2.52; P < .0001). Bioinformatic analysis showed that LOX expression was associated with hypoxia‐inducible factor‐1α (HIF‐1α) and the hypoxia cascade, suggesting that HIF‐1α or hypoxia regulates LOX expression and induces epithelial‐mesenchymal transition (EMT). In vitro, LOX and HIF‐1α were involved in migration and invasion capability. High LOX expression is associated with EMT markers and predicts early recurrence and poor survival in patients with HCC. These findings indicate that lysyl oxidase could be a potential therapeutic target for early recurrence of HCC.

Functional characterization of anti-cancer sphingolipids from the marine crab Dromia dehanni

Sphingolipids have been considered for many years only as structural components of membranes. It is now acknowledged that they are also involved in controlling cellular processes such as proliferation.The present work was designed to find the anticancer activity of the crab Dromia dehanni hemolymph in in-vivo and in vitro with special reference to the anticancer compound sphingolipids isolation and characterization. The active fraction of the purified hemolymph was subjected to NMR and ESI-MS/MS analysis. The ESI-MS/MS spectrum exhibited intense signals for sodiated molecular ions [M + Na]⁺ of sphingomyelins (SM) identified as N-2-O-Acetyl-12 pentadecenoyl sphingosine phosphorylcholine, N-9-eicosenoyl- sphinganine phosphocholine and the corresponding dehydro sphingomyelin, N-9-eicosenoyl- dehydro- sphinganine phosphocholine along with the ions at m/z 147, 184 characteristic of phosphocholine. The present study revealed D. dehaani might be a great source for the novel anti-cancer compounds which can be used for human benefits.

Predictors of hepatocellular carcinoma occurrence after direct-acting antiviral therapy in patients with hepatitis C virus infection

AIM

The predictors for the development of hepatocellular carcinoma (HCC) after direct-acting antiviral (DAA) treatment were investigated.

METHODS

A total of 1174 patients with chronic hepatitis C virus infection were treated with DAA therapy (sofosbuvir and ledipasvir [n = 615], sofosbuvir and ribavirin [n = 380], and daclatasvir and asunaprevir [n = 179]) and achieved sustained virologic response (SVR). The HCC development rate and the factors that might contribute to the development of HCC after the end of DAA treatment were analyzed.

RESULTS

During the median observation period of 537 days, HCC developed in 33 cases. The incidence of HCC was 1.9%, 3.2%, and 4.1% at 1, 1.5, and 2 years after the end of DAA therapy, respectively. Multivariate analysis with pre- and post-treatment factors identified the Fibrosis-4 (FIB-4) index (hazard ratio [HR] = 1.09; 95% confidence interval [CI], 1.021-1.178; P = 0.011) and post-treatment α-fetoprotein (AFP) (HR = 1.11; 95% CI, 1.054-1.172; P < 0.001) as independent factors that contributed to the development of HCC after DAA therapy. Using these identified parameters, a new scoring system (0 to 2 points) was established. Patients in the high-score group (2 points) could be identified as having a significantly higher risk of HCC development, and the respective 1- and 2-year cumulative incidence rates of HCC were 6.1% and 14.4%.

CONCLUSIONS

A high FIB-4 index and a high post-treatment AFP at the end of DAA treatment were the independent predictors for developing HCC after DAA treatment. For patients with these risk factors, extra attention to the possibility of HCC development is needed.

Genomic Medicine and Implications for Hepatocellular Carcinoma Prevention and Therapy

The pathogenesis of hepatocellular carcinoma (HCC) is poorly understood, but recent advances in genomics have increased our understanding of the mechanisms by which hepatitis B virus, hepatitis C virus, alcohol, fatty liver disease, and other environmental factors, such as aflatoxin, cause liver cancer. Genetic analyses of liver tissues from patients have provided important information about tumor initiation and progression. Findings from these studies can potentially be used to individualize the management of HCC. In addition to sorafenib, other multi-kinase inhibitors have been approved recently for treatment of HCC, and the preliminary success of immunotherapy has raised hopes. Continued progress in genomic medicine could improve classification of HCCs based on their molecular features and lead to new treatments for patients with liver cancer.

Fruit and vegetable intake and liver cancer risk: a meta-analysis of prospective cohort studies

The associations of vegetable and fruit intake with liver cancer risk have been inconsistent based on epidemiological studies.

Molecular Mechanisms Involved in HCC Recurrence after Direct-Acting Antiviral Therapy

Chronic hepatitis C is associated with a high risk of developing hepatocellular carcinoma (HCC) because of a direct effect of the Hepatitis C Virus (HCV) proteins and an indirect oncogenic effect of chronic inflammation and impaired immune response. The treatment of chronic hepatitis C markedly reduces all-cause mortality; in fact, interferon-based treatment has shown a reduction of HCC incidence of more than 70%. The recent introduction of the highly effective direct-acting antivirals (DAAs) has completely changed the scenario of chronic hepatitis C (CHC) with rates of HCV cure over 90%. However, an unexpectedly high incidence of HCC recurrence was observed in patients after DAA treatment (27% versus 0.4–2% in patients who received interferon treatment). The mechanism that underlies the high rate of tumor relapse is currently unknown and is one of the main issues in hepatology. We reviewed the possible mechanisms involved in HCC recurrence after DAA treatment.

Overexpression of heat shock protein HSP90AA1 and translocase of the outer mitochondrial membrane TOM34 in HCV-induced hepatocellular carcinoma: A pilot study

OBJECTIVE

Identification of new molecular markers to enhance early diagnosis, prognosis and/or treatment of hepatocellular carcinoma (HCC) is a need. TOM34 (34 kDa-translocase of the outer mitochondrial membrane) protein expression deregulation has demonstrated to be involved in the growth of many cancers. Here, we aimed at evaluating serum TOM34 and some heat shock proteins (HSPA4, HSPA1B, and HSP90AA1) expressions in hepatitis C virus (HCV)-related cirrhosis and HCV-induced HCC relative to controls and correlating these expressions to the clinicopathological data.

METHODS

Serum specimens were collected from 90 patients with HCV associated complications (30 cirrhotic, 30 early HCC and 30 late HCC) and 60 controls. Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) was performed for relative quantification of the four target genes using the Livak method. In silico network analysis was also executed to explore the contribution of the genes in liver cancer.

RESULTS

The serum TOM34 and HSP90AA1 transcripts were significantly upregulated in HCC patients compared to cirrhotic ones with more up-regulation in late HCC patients. Receiver operating characteristic analysis showed the optimum cutoff value of 0.625 corresponding to 71.7% sensitivity and 56.7% specificity, and an area under the curve (AUC) of 0.705 to discriminate HCC from cirrhotic groups (P = .002). In multivariate analysis, ordination plot showed obvious demarcation between the study groups caused by the higher levels of TOM34 among other variables.

CONCLUSIONS

TOM34 and its partner HSP90AA1 might be used as a potential biomarker for monitoring HCV-induced HCC progression in the Egyptian population. Future large-scale validation studies are warranted.

Diagnosis and survival values of neutrophil-lymphocyte ratio (NLR) and red blood cell distribution width (RDW) in esophageal cancer

BACKGROUND

Recent studies have borne out claims that inflammation has a vital role in the development and progression of many diseases, including cancers. It has been reported that neutrophil-lymphocyte ratio (NLR) and red blood cell distribution width (RDW) could act as independent prognostic factors for several malignant tumors. We evaluated the diagnosis and prognosis values of preoperative inflammatory indicators, including NLR and RDW in esophageal cancer (EC).

METHODS

We retrospectively analyzed the clinical data of 354 EC patients and 220 early esophageal cancer (EEC) undergoing potentially curative esophagectomy in Shandong Provincial Hospital Affiliated to Shandong University and chose 201 age and sex-matched healthy volunteers as the control group. We compared the clinicopathological features, survival curves and prognosis of the EC patients between the high and low groups according to the cutoff values of NLR and RDW.

RESULTS

Significant higher preoperative NLR and RDW values were detected in patients with EEC and EC compared to the healthy controls (P < .001). A high RDW was significantly associated with an older age (P < .05). NLR and RDW values after surgery in EC group were significantly higher than those before surgery (P < .001 and P < .001, respectively). For EEC group, a higher RDW value showed a significantly worse overall survival (OS) and disease-free survival (DFS) (P = .040 and P = .013, respectively). For EC group, an increased NLR indicated a significantly association with poor overall survival (OS) (P = .004) and DFS (P = .001). Preoperative NLR can act as an independent prognostic indicator for EC.

CONCLUSION

The preoperative NLR and RDW are convenient, practical easily measured biomarkers of clinical diagnosis and prognostic assessment of patients with EC. Furthermore, NLR was more effective than RDW acting as an independent prognostic biomarker for EC.

Viral Persistence and Chronicity in Hepatitis C Virus Infection: Role of T-Cell Apoptosis, Senescence and Exhaustion

Hepatitis C virus (HCV) represents a challenging global health threat to ~200 million infected individuals. Clinical data suggest that only ~10–15% of acutely HCV-infected individuals will achieve spontaneous viral clearance despite exuberant virus-specific immune responses, which is largely attributed to difficulties in recognizing the pathognomonic symptoms during the initial stages of exposure to the virus. Given the paucity of a suitable small animal model, it is also equally challenging to study the early phases of viral establishment. Further, the host factors contributing to HCV chronicity in a vast majority of acutely HCV-infected individuals largely remain unexplored. The last few years have witnessed a surge in studies showing that HCV adopts myriad mechanisms to disconcert virus-specific immune responses in the host to establish persistence, which includes, but is not limited to viral escape mutations, viral growth at privileged sites, and antagonism. Here we discuss a few hitherto poorly explained mechanisms employed by HCV that are believed to lead to chronicity in infected individuals. A better understanding of these mechanisms would aid the design of improved therapeutic targets against viral establishment in susceptible individuals.

Combined Preoperative ALBI and FIB-4 Is Associated with Recurrence of Hepatocellular Carcinoma After Curative Hepatectomy

BACKGROUND AND PURPOSE

Chronic inflammatory response is a risk factor for hepatocarcinogenesis and recurrence. This study aimed to develop a nomogram incorporating the combined albumin-bilirubin (ALBI) and fibrosis-4 (FIB-4) scores and the peritumoral inflammation score (PIS) to predict postoperative recurrence-free survival (RFS) of hepatocellular carcinoma (HCC).

METHODS

The prognostic roles of preoperative ALBI and FIB-4 scores for HCC recurrence were investigated, and a nomogram was developed. The predictive ability of the nomogram was compared with the American Joint Commission on Cancer (AJCC) and Barcelona Clinic Liver Cancer (BCLC) staging systems for HCC. Necroinflammatory activity in the peritumoral liver tissues was evaluated by hematoxylin and eosin (H&E) staining.

RESULTS

Combined ALBI and FIB-4 was associated with PIS in the training and validation cohorts (r = 0.342 and 0.473, both P < 0.001), and all of the scores exhibited predictive value for RFS of HCC. The independent predictive factors of RFS such as AFP, tumor number, tumor size, microvascular invasion, PIS, and combined ALBI and FIB-4 were included in the corresponding nomogram. In the training cohort, the C-index of the RFS nomogram was 0.722. ROC analyses showed that the RFS nomogram had a larger AUC (0.739) than the AJCC and BCLC staging systems. These results were verified by the validation cohort.

CONCLUSIONS

The proposed nomogram incorporating PIS and combined ALBI and FIB-4 was associated with recurrence for HCC following curative hepatectomy.

Update in global trends and aetiology of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common primary cancer of the liver responsible for an increasing number of cancer-related deaths, especially in developing economies of Asia and Africa. A plethora of risk factors have been described in the literature. Some of the important ones include chronic viral hepatitis, liver cirrhosis, environmental toxins such as aflatoxin, non-alcoholic fatty liver disease, lifestyle factors like alcohol consumption, smoking, and dietary factors, metabolic diseases like diabetes mellitus and obesity, and genetic and hereditary disorders. The development of HCC is complex involving sustained inflammatory damage leading to hepatocyte necrosis, regeneration, and fibrotic deposition. It also poses multiple challenges in diagnosis and treatment despite advances in diagnostic, surgical, and other therapeutic advancements. This is a narrative review of findings of multiple studies that were retrieved from electronic databases like PubMed, MEDLINE, Embase, Google Scholar, Scopus, and Cochrane. We summarise the current knowledge regarding the epidemiology and various risk factors for the development of HCC with a brief note on various prevention strategies.

Potential Role of Microfibrillar-Associated Protein 4, Fibrotic Indices and Oxidative Stress in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related mortality worldwide. In an attempt to understand some potential mechanisms of persistence and oncogenicity of Hepatitis C virus (HCV)-related HCC, microfibrillar-associated protein 4 (MFAP4), fibrotic indices and oxidative status biomarkers were assessed in the sera of 50 patients with HCV-associated HCC, 25 patients with HCV-related liver cirrhosis and 15 healthy individuals. Serum oxidized Coenzyme Q10 (CoQ10) and malondialdehyde showed significant elevation in HCC patients compared to the control group (p < 0.001), as well as cirrhotic patients (p < 0.05 and p < 0.001, respectively), while serum glutathione content and superoxide dismutase activity were significantly decreased in HCC patients compared to the control group (p < 0.001). Serum MFAP4, aspartate aminotransferase to platelet ratio index (APRI), fibrosis index based on the 4 factors (FIB-4) and Forns index showed significant increase in HCC patients compared to the control group (p < 0.001), while only APRI and FIB-4 were significantly different between HCC and cirrhotic patients (p < 0.05), with a sensitivity of 86% and 92%, respectively, at cut off ≥0.7 for APRI and ≥1.57 for FIB-4. Therefore, increasing oxidative stress and fibrosis might mediate HCV induced cirrhosis and HCC. APRI and FIB-4 may be used as a simple non-expensive formula for the screening of HCC rather than MFAP4.

Molecular Mechanisms of Hepatocarcinogenesis Following Sustained Virological Response in Patients with Chronic Hepatitis C Virus Infection

Despite the success of direct-acting antiviral (DAA) agents in treating chronic hepatitis C virus (HCV) infection, the number of cases of HCV-related hepatocellular carcinoma (HCC) is expected to increase over the next five years. HCC develops over the span of decades and is closely associated with fibrosis stage. HCV both directly and indirectly establishes a pro-inflammatory environment favorable for viral replication. Repeated cycles of cell death and regeneration lead to genomic instability and loss of cell cycle control. DAA therapy offers >90% sustained virological response (SVR) rates with fewer side effects and restrictions than interferon. While elimination of HCV helps to restore liver function and reverse mild fibrosis, post-SVR patients remain at elevated risk of HCC. A series of studies reporting higher than expected rates of HCC development among DAA-treated patients ignited debate over whether use of DAAs elevates HCC risk compared to interferon. However, recent prospective and retrospective studies based on larger patient cohorts have found no significant difference in risk between DAA and interferon therapy once other factors are taken into account. Although many mechanisms and pathways involved in hepatocarcinogenesis have been elucidated, our understanding of drivers specific to post-SVR hepatocarcinogenesis is still limited, and lack of suitable in vivo and in vitro experimental systems has hampered efforts to examine etiology-specific mechanisms that might serve to answer this question more thoroughly. Further research is needed to identify risk factors and biomarkers for post-SVR HCC and to develop targeted therapies based on more complete understanding of the molecules and pathways implicated in hepatocarcinogenesis.

Hepatocellular carcinoma occurrence in DAA-treated hepatitis C virus patients: Correlated or incidental? A brief review

Hepatitis C virus (HCV) chronic infection induces liver fibrosis and cirrhosis but is also responsible for a significant portion of hepatocellular carcinoma (HCC) occurrence. Since it was recognized as a causative factor of chronic hepatitis, there have been multiple efforts towards viral eradication, leading to the first-generation HCV treatment that was based on interferon (IFN)-αand its analogs, mainly PEGylated interferon-α (PEG IFNα). Sustained virological response (SVR), defined as the absence of detectable RNA of HCV in blood serum for at least 24 wk after discontinuing the treatment, was accepted as a marker of viral clearance and was achieved in approximately one-half of patients treated with PEG IFNα regimens. Further research on the molecular biology of HCV gave rise to a new generation of drugs, the so-called direct antiviral agents (DAAs). DAA regimens, as implied by their name, interfere with the HCV genome or its products and have high SVR rates, over 90%, after just 12 wk of per os treatment. Although there are no questions about their efficacy or their universality, as they lack the contraindication for advanced liver disease that marks PEG IFNα, some reports of undesired oncologic outcomes after DAA treatment raised suspicions about possible interference of this treatment in HCC development. The purpose of the present review is to investigate the validity of these concerns based on recent clinical studies, summarize the mechanisms of action of DAAs and survey the updated data on HCV-induced liver carcinogenesis.

Transcriptional Regulatory Networks in Hepatitis C Virus-induced Hepatocellular Carcinoma

Understanding the transcriptional regulatory elements that influence the progression of liver disease in the presence of hepatitis C virus (HCV) infection is critical for the development of diagnostic and therapeutic approaches. Systems biology provides a roadmap by which these elements may be integrated. In this study, a previously published dataset of 124 microarray samples was analyzed in order to determine differentially expressed genes across four tissue types/conditions (normal, cirrhosis, cirrhosis HCC, and HCC). Differentially expressed genes were assessed for their functional clustering and those genes were annotated with their potential transcription factors and miRNAs. Transcriptional regulatory networks were constructed for each pairwise comparison between the 4 tissue types/conditions. Based on our analysis, it is predicted that the disruption in the regulation of transcription factors such as AP-1, PPARγ, and NF-κB could contribute to the liver progression from cirrhosis to steatosis and eventually to HCC. Whereas the condition of the liver digresses, the downregulation of miRNAs' (such as miR-27, Let-7, and miR-106a) expression makes the transition of the liver through each pathological stage more apparent. This preliminary data can be used to guide future experimental work. An understanding of the transcriptional regulatory attributes acts as a road map to help design interference strategies in order to target the key regulators of progression of HCV induced HCC.

Generic chemoprevention of hepatocellular carcinoma

Chronic fibrotic liver disease caused by viral or metabolic etiologies is a high-risk condition for developing hepatocellular carcinoma (HCC). Even after curative treatment of early-stage HCC tumor, the carcinogenic microenvironment persists in the remnant diseased liver and supports the development of de novo HCC tumors (de novo HCC recurrence). Therefore, prevention of HCC development in patients at risk of not only first-primary but also second-primary HCC tumors is theoretically the most impactful strategy to improve patient prognosis. However, no such therapy has been established to date. One major challenge is the identification of clinically relevant targets that can be achieved by utilizing the reverse-engineering strategy of chemoprevention discovery, which integrates omics information from clinical cohorts with completed follow-up for cancer development. Clinical and experimental studies have suggested etiology-specific and generic candidate HCC chemoprevention strategies, including statins, antidiabetic drugs, selective molecular targeted agents, and dietary and nutritional substances. Clinical testing of the candidate compounds can be cost-effectively performed by combining it with HCC risk biomarker evaluation to specify the target patient population most likely to benefit from the therapy. Nontoxic, generic agents will have broad clinical applicability across the diverse HCC etiologies and clinical contexts and are expected to substantially improve the still dismal prognosis of HCC.

HCV adaptation to HIV coinfection

Human immunodeficiency virus (HIV) infection is rising as a leading cause of morbidity and mortality among hepatitis C virus (HCV)-infected patients. Both viruses interact in co-infected hosts, which may affect their intra-host evolution, potentially leading to differing genetic composition of viral populations in co-infected (CIP) and mono-infected (MIP) patients. Here, we investigate genetic differences between intra-host variants of the HCV hypervariable region 1 (HVR1) sampled from CIP and MIP. Nucleotide (nt) sequences of intra-host HCV HVR1 variants (N = 28,622) obtained from CIP (N = 112) and MIP (n = 176) were represented using 148 physical-chemical (PhyChem) indexes of DNA nt dimers. Significant (p < .0001) differences in the means and frequency distributions of 7 PhyChem properties were found between HVR1 variants from both groups. Linear projection analysis of 29 PhyChem features extracted from such PhyChem properties showed that the CIP and MIP HVR1 variants have a distinct distribution in the modeled 2D-space, with only ~1.3% of PhyChem profiles (N = 6782), shared by all HVR1 variants, being found in both groups. Probabilistic neural network (PNN) and naïve Bayesian (NB) classifiers trained on the PhyChem features accurately classified HVR1 variants by the group in cross-validation experiments (AUROC ≥ 0.96). Similarly, both models showed a high accuracy (AUROC ≥ 0.95) when evaluated on a test dataset of HVR1 sequences obtained from 10 patients, data from whom were not used for model building. Both models performed at the expected lower accuracy on randomly labeled datasets in cross-validation experiments (AUROC = 0.50). The random-label trained PNN showed a similar drop in accuracy on the test dataset (AUROC = 0.48), indicating that the detected associations were unlikely due to random correlations. Marked differences in genetic composition of HCV HVR1 variants sampled from CIP and MIP suggest differing intra-host HCV evolution in the presence of HIV infection. PhyChem features identified here may be used for detection of HIV infection from intra-host HCV variants alone in co-infected patients, thus facilitating monitoring for HIV introduction to high-risk populations with high HCV prevalence.

Thermostable hepatitis C virus JFH1-derived variant isolated by adaptation to Huh7.5.1 cells

Hepatitis C virus (HCV) infection and propagation in cultured cells have mainly been investigated using the infectious clinical clone JFH1. However, its infectivity is not high enough for infection to be detected easily. In this study, we attempted to isolate HCV-JFH1 variants adapted to human hepatoma Huh7.5.1 cells. By performing serial passages of the wild-type HCV-JFH1 in Huh7.5.1 cells, we obtained a variant that was capable of inducing severe cytopathic effects and showed approximately 700-fold higher infectivity than the wild-type HCV-JFH1. Further, when highly permissive Huh7.5.1-8 cells were infected with this variant, viral particles were produced at >10¹¹ copies ml^-1, making this variant one of the most efficient HCV production systems. Two adaptive mutations were noted in the variant genome: a1994c (K74T) in the core protein region and t3014c (I414T) in the E2 protein region. Both mutations contributed to enhanced infectivity and their combination showed synergistic effects in this regard. An examination of recombinant viruses carrying K74T, I414T and K74T/I414T mutations revealed that none of the mutations had an effect on the steps after viral entry (genome replication, particle assembly and egress), but led to the viral infection becoming less dependent on scavenger receptor class B type I, changes of the infectious particles to a broader and lower range of densities, and enhanced thermal stability of the infectious viruses. Thus, this Huh7.5.1-adapted HCV-JFH1 variant with higher and stable infectivity should be a valuable tool for studying the molecular mechanisms behind the life cycle of HCV and for antiviral screening.

HCV-induced EGFR-ERK signaling promotes a pro-inflammatory and pro-angiogenic signature contributing to liver cancer pathogenesis

HCV is a major risk factor for hepatocellular carcinoma (HCC). HCC development in chronically infected HCV patients has until now been attributed to persistent inflammation and interference of viral proteins with host cell signaling. Since activation of the epidermal growth factor receptor (EGFR) presents a crucial step in HCV entry, we aimed at investigating whether EGFR signaling may contribute to the pathogenesis of HCV-related HCC. By applying microarray analysis, we generated a gene expression signature for secreted proteins in HCV-infected hepatoma cells. This gene signature was enriched for inflammatory and angiogenic processes; both crucially involved in HCC development. RT-qPCR analysis, conducted on the entire list of upregulated genes, confirmed induction of 11 genes (AREG, IL8, CCL20, CSF1, GDF15, IGFBP1, VNN3, THBS1 and PAI-1) in a virus titer- and replication-dependent manner. EGFR activation in hepatoma cells largely mimicked the gene signature seen in the infectious HCV model. Further, the EGFR-ERK pathway, but not Akt signaling, was responsible for this gene expression profile. Finally, microarray analysis conducted on clinical data from the GEO database, revealed that our validated gene expression profile is significantly represented in livers of patients with HCV-related liver pathogenesis (cirrhosis and HCC) compared to healthy livers. Taken together, our data indicate that persistent activation of EGFR-ERK signaling in chronically infected HCV patients may induce a specific pro-inflammatory and pro-angiogenic signature that presents a new mechanism by which HCV can promote liver cancer pathogenesis. A better understanding of the key factors in HCV-related oncogenesis, may efficiently direct HCC drug development.

High prevalence of a variety of autoantibodies in a population of hepatitis C virus-infected individuals

Hepatitis C virus (HCV) infection has been related to self-reactivity, extrahepatic manifestations and autoimmune diseases. The main goals of this work were to study the prevalence of autoantibodies and their relationship with viral titers and biochemical markers of hepatic damage in patients infected with HCV. Autoantibodies (ANA, AMA, SMA, APC, LKM, DNAds, ANCA, ATG and RF) were determined in 73 individuals with chronic HCV infection and 44 healthy volunteers. The presence of these antibodies was related to demographic variables, viral titers and biochemical parameters. A high prevalence of autoantibodies, particularly for RF, that was associated with female gender was observed in HCV-infected patients. In addition, SMA, ANA and ATG showed increased frequencies in HCV infection. Interestingly, the concurrent detection of SMA and more than one autoantibody was associated with high gGT levels. Notably, concurrent higher gGT, HCV and SMA levels were observed in male patients as compared to their female counterparts. These results indicate a relationship between HCV infection and the concurrent detection of various autoantibodies in the absence of symptoms of autoimmune diseases. They also suggest a link among the presence of a variety of autoantibodies simultaneously with SMA, increased gGT levels and HCV titers in a population of male patients.