Occult hepatitis B virus and hepatocellular carcinoma

Genetic diversity and occult hepatitis B infection in Africa: A comprehensive review

BACKGROUND

Occult hepatitis B infection (OBI) is a globally prevalent infection, with its frequency being influenced by the prevalence of hepatitis B virus (HBV) infection in a particular geographic region, including Africa. OBI can be transmitted through blood transfusions and organ transplants and has been linked to the development of hepatocellular carcinoma (HCC). The associated HBV genotype influences the infection.

AIM

To highlight the genetic diversity and prevalence of OBI in Africa.

METHODS

This systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and involved a comprehensive search on PubMed, Google Scholar, Science Direct, and African Journals Online for published studies on the prevalence and genetic diversity of OBI in Africa.

RESULTS

The synthesis included 83 articles, revealing that the prevalence of OBI varied between countries and population groups, with the highest prevalence being 90.9% in patients with hepatitis C virus infection and 38% in blood donors, indicating an increased risk of HBV transmission through blood transfusions. Cases of OBI reactivation have been reported following chemotherapy. Genotype D is the predominant, followed by genotypes A and E.

CONCLUSION

This review highlights the prevalence of OBI in Africa, which varies across countries and population groups. The study also demonstrates that genotype D is the most prevalent.

Occult Hepatitis B Infection among Blood Donors in Northwestern Greece

Background: Occult hepatitis B virus infection (OBI) is characterized by the presence of HBV DNA in individuals who test negative for hepatitis B surface antigen (HBsAg). It poses diagnostic challenges and contributes to chronic liver diseases. Understanding its epidemiology, pathogenesis and clinical outcomes remains essential. This study aimed to assess the prevalence and characteristics of OBI in Northwestern Greece. Methods:Serum samples were prospectively collected from 702 blood donors at the University Hospital of Ioannina, Greece, between February 2018 and September 2022. The investigation focused on the presence of hepatitis B virus (HBV) markers, utilizing the Abbott Architect HBsAg and HBcAb HB Qualitative II kit for the detection of HBsAg and anti-HBc, respectively. Further analysis was conducted on serum samples from individuals who tested negative for HBsAg but positive for anti-HBc, employing polymerase chain reaction (PCR) to detect HBV-DNA. In instances of OBI, sequencing and mutation analysis of the HBV pre-S/S gene were carried out for comprehensive characterization. Results:Screening revealed 56 cases (7.9%) with active HBV infection (HBsAg positive) and identified 144 cases (20.5%) indicative of past HBV infection (HBsAg negative, anti-HBc positive). Additionally, a prevalence of 5.4% (38/702) of OBI was detected. Among these, 36 cases exhibited a low HBV DNA load of less than 225 IU/mL. Notably, one OBI patient was co-infected with HIV. Furthermore, two cases of OBI with high HBV-DNA levels exceeding 200,000 IU/ml were detected. Sequencing analysis unveiled S- and pre-S mutations in four cases of OBI, including both instances with elevated HBV-DNA levels. Conclusion:In a region with a high proportion of immigrants from countries where HBV is endemic, a high prevalence of HBV infection and occult HBV infection (OBI) has been detected. Furthermore, mutations in the S gene were found to be associated with cases of OBI with high levels of HBV-DNA. However, additional research is needed to validate the results and understand the clinical relevance of specific OBI mutations for disease progression and treatment efficacy.

Killer cell immunoglobulin-like receptor alleles influence susceptibility to occult hepatitis B infection in West African population

Occult hepatitis B infection (OBI) is a public health problem in Burkina Faso. OBI represents a risk factor for the development of cirrhosis and hepatocellular carcinoma (HCC). OBI could be due to mutant viruses undetectable by HBsAg assays or a strong suppression of viral replication and gene expression under the pression of the host immune system. To investigate the role of killer cell immunoglobulin-like receptor (KIR) gene polymorphisms in patients with OBI in Burkina Faso compared to healthy and chronic hepatitis B subjects. A total of 286 participants was recruited, including 42 cases of OBI, 110 cases of chronic hepatitis B and 134 HBV negative subjects. SSP-PCR was performed to search for the presence of KIR genes. The HBV viral load was determined by qPCR. The frequencies of the activator gene KIR2DS5 (P=0.045) and the pseudogene KIR2DP1 (P<0.001) in patients with OBI were higher than those in patients with chronic hepatitis B. These genes are associated with susceptibility of occult hepatitis B infection. The frequencies of the inhibitory KIR gene KIR2DL3 (P=0.01) of patients with occult hepatitis B were lower than those in chronic hepatitis B patients. This gene KIR2DL3 is associated with protection against occult hepatitis B infection. Also, the frequencies of the inhibitory KIR genes KIR2DL2 (P<0.001), KIR2DL3 (P<0.001) and activators KIR2DS2 (P<0.001) in chronic hepatitis B patients were higher compared to the frequencies of the KIR genes in healthy subjects. These genes KIR2DL3, KIR2DL5 (A, B), KIR3DL3, KIR3DS1, KIR2DL2 and KIR2DS2 are thought to be genes associated with the susceptibility to OBI. The KIR2DS5 and KIR2DP1 genes could be associated with susceptibility to OBI. As for the KIR gene KIR2DL3 could be associated with protection against occult hepatitis B infection.

Associations of Race and Ethnicity with Hepatocellular Carcinoma, Decompensation, and Mortality in US Veterans with Cirrhosis

BACKGROUND

Among patients with cirrhosis, it remains unclear whether there are racial/ethnic differences in cirrhosis complications and mortality. We examined the associations between race/ethnicity and risk for hepatocellular carcinoma (HCC), cirrhosis decompensation, and all-cause mortality overall and by cirrhosis etiology.

METHODS

US Veterans diagnosed with cirrhosis from 2001 to 2014 (n = 120,992), due to hepatitis C virus (HCV; n = 55,814), alcohol-associated liver disease (ALD; n = 36,323), hepatitis B virus (HBV; n = 1,972), nonalcoholic fatty liver disease (NAFLD; n = 17,789), or other (n = 9,094), were followed through 2020 for incident HCC (n = 10,242), cirrhosis decompensation (n = 27,887), and mortality (n = 81,441). Multivariable Cox proportional hazards regression was used to estimate adjusted hazard ratios (aHR) and 95% confidence intervals (CI).

RESULTS

Compared with non-Hispanic White patients, Hispanic patients had higher risk for HCC overall (aHR, 1.32; 95% CI, 1.24-1.41) and by cirrhosis etiology, particularly for ALD- (aHR, 1.63; 95% CI, 1.42-1.87) and NAFLD-cirrhosis (aHR, 1.76; 95% CI, 1.41-2.20), whereas non-Hispanic Black patients had lower HCC risk in ALD- (aHR, 0.79; 95% CI, 0.63-0.98) and NAFLD-cirrhosis (aHR, 0.54; 95% CI, 0.33-0.89). Asian patients had higher HCC risk (aHR, 1.70; 95% CI, 1.29-2.23), driven by HCV- and HBV-cirrhosis. Non-Hispanic Black patients had lower risk for cirrhosis decompensation overall (aHR, 0.71; 95% CI, 0.68-0.74) and by cirrhosis etiology. There was lower risk for mortality among all other racial/ethnic groups compared with non-Hispanic White patients.

CONCLUSIONS

Race/ethnicity is an important predictor for risk of developing HCC, decompensation, and mortality.

IMPACT

Future research should examine factors underlying these racial/ethnic differences to inform prevention, screening, and treatment for patients with cirrhosis.

A Historical Overview on the Role of Hepatitis B and C Viruses as Aetiological Factors for Hepatocellular Carcinoma

Hepatitis B virus (HBV) and hepatitis C virus (HCV) are the leading cause of hepatocellular carcinoma (HCC) worldwide. Currently, HBV-related HCC predominates in Sub-Saharan Africa and South-East-Asia, while HCV-related HCC predominates in northern Africa and in the western world. Liver cirrhosis is the underlying condition in most HBV cases and in nearly all HCV cases. Several cofactors, viral and non-viral, play a role in the progression toward HCC: dual HBV/HCV infection, HDV, HIV, alcohol intake, smoking, diabetes mellitus, obesity, and NAFLD/NASH. HBV vaccine is effective in preventing both infection and HCC; antiviral drugs may suppress HBV replication and eradicate HCV infection, halting progression to HCC. Inequalities exist between high- and low-income countries with respect to vaccine availability and access to antivirals. These factors represent barriers to the control of HCC incidence. Lack of an effective vaccine against HCV is also a serious barrier to HCV elimination and HCC prevention. The most crucial steps and knowledge that have arisen over time on the association between the two major hepatotropic viruses and HCC are discussed in this historical review.

Occult hepatitis B in blood donation centers

Occult hepatitis B (OHB) is characterized by the presence of hepatitis B virus (HBV) DNA in the blood of individuals who test negative for the hepatitis B surface antigen (HBsAg). OHB in blood donors can lead to HBV transmission through transfusions, yet the prevalence of OHB in Basrah, Iraq, is unknown. This study aimed to determine the prevalence of OHB in blood donation centers in Basrah and investigate the immune response to HBV in OHB-positive donors. We recruited 450 blood donors and categorized them into four groups based on HBV markers: the HBsAg-negative/HBsAb-negative/HBcAb-positive group, the recovery group (HBsAg-negative/HBsAb-positive/HBcAb-positive), the patient group (HBsAg-positive/HBsAb-negative/HBcAb-positive), and the apparently healthy group (negative for all HBV markers). We measured levels of IgG, IgM, complement components (C3 and C4), ALT, AST, and serum ALP in OHB-positive donors. Of the 450 donors, 97 (21.6%) were OHB-positive. IgG levels were significantly higher than IgM levels in OHB-positive donors. Healthy and HBsAg-negative/HBsAb-positive donors had significantly lower C3 levels than patients. IgG levels were significantly higher than IgM in both the patient and recovery groups. C3 levels were higher than C4 levels in all groups. The serum ALP level was significantly higher in the patient group. OHB prevalence in Basrah blood donors is high, indicating the potential for HBV transmission. OHB-positive donors showed an immune response to HBV. Our study provides insights into OHB prevalence and immune response in Basrah, with implications for diagnostic and therapeutic approaches in blood donation centers.

Occult hepatitis B virus infection among patients with chronic liver disease of unidentified cause, Addis Ababa Ethiopia

Occult hepatitis B virus infection (OBI) characterized by the absence of detectable HBsAg in the presence of HBV DNA in the serum and/or liver tissue remains a potential risk of transmission and diseases progression among different population groups. It could be associated with asymptomatic case up to chronic liver disease (CLD) and hepatocellular carcinoma (HCC). The objective of this study was to assess the magnitude and characteristics of OBI among patients with CLD of unidentified cause in Addis Ababa, Ethiopia. The study was conducted at the gastroenterology & hepatology referral clinic of three government and two private hospitals in Addis Ababa. Known CLD patients as evidenced by clinical and imaging criteria and/or with HBV surface antigen (HBsAg) negative results using rapid test kit were included. ELISA serological test to anti-HBc Ab, anti HBsAg Ab, and HBsAg were determined using BIORAD kits [https://www.bio-rad.com]. HBV-DNA was amplified, and viral loads were determined by quantitative real-time PCR using Abbott m2000rt platform following the manufacturer's instructions. Data analysis was done using SPSS version 20.A total of 48 CLD patients with no identified cause for their liver disease were identified during the study period. All the patients had evidence of CLD by clinical and imaging criteria and nine were excluded. Three (7.69%) of the 39 patients tested positive for HBsAg test done by ELISA making the negative predictive value of the rapid test kits 92.3% compared to ELISA. The remaining 36 patients had serology test for HBV and 16 (44.4%) had positive anti-HBV core antibody. Two (5.56%) of the 36 patients with HBV viral load determination had detectable HBV DNA suggesting presence of an occult hepatitis B infection. Occult hepatitis B infection is found to be an aetiology among CLD patients labelled as having no identified cause by the current standard of care using rapid HBsAg kits in a subset of patients in Ethiopia. This study signifies the high rate of OBI and past evidence of HBV infection among CLD patients and thus nucleic acid testing and/or anti-HBc shall be integrated to the routine health care system to minimize HBV infection risk of transmission and to enhance patient care.

Viral Encoded miRNAs in Tumorigenesis: Theranostic Opportunities in Precision Oncology

About 15% of all human cancers have a viral etiology. Although progress has been made, understanding the viral oncogenesis and associated molecular mechanisms remain complex. The discovery of cellular miRNAs has led to major breakthroughs. Interestingly, viruses have also been discovered to encode their own miRNAs. These viral, small, non-coding miRNAs are also known as viral-miRNAs (v-miRNAs). Although the function of v-miRNAs largely remains to be elucidated, their role in tumorigenesis cannot be ignored. V-miRNAs have also been shown to exploit the cellular machinery to benefit viral replication and survival. Although the discovery of Hepatitis C virus (HCV), and its viral miRNAs, is a work in progress, the existence of HPV-, EBV-, HBV-, MCPyV- and KSHV-encoded miRNA has been documented. V-miRNAs have been shown to target host factors to advance tumorigenesis, evade and suppress the immune system, and deregulate both the cell cycle and the apoptotic machinery. Although the exact mechanisms of v-miRNAs-induced tumorigenesis are still unclear, v-miRNAs are active role-players in tumorigenesis, viral latency and cell transformation. Furthermore, v-miRNAs can function as posttranscriptional gene regulators of both viral and host genes. Thus, it has been proposed that v-miRNAs may serve as diagnostic biomarkers and therapeutic targets for cancers with a viral etiology. Although significant challenges exist in their clinical application, emerging reports demonstrate their potent role in precision medicine. This review will focus on the roles of HPV-, HCV-, EBV-, HBV-, MCPyV-, and KSHV-produced v-miRNAs in tumorigenesis, as effectors in immune evasion, as diagnostic biomarkers and as novel anti-cancer therapeutic targets. Finally, it will discuss the challenges and opportunities associated with v-miRNAs theranostics in precision oncology.

Occult Hepatitis B Virus Infection: An Update

Occult hepatitis B virus (HBV) infection (OBI) refers to a condition in which replication-competent viral DNA is present in the liver (with detectable or undetectable HBV DNA in the serum) of individuals testing negative for the HBV surface antigen (HBsAg). In this peculiar phase of HBV infection, the covalently closed circular DNA (cccDNA) is in a low state of replication. Many advances have been made in clarifying the mechanisms involved in such a suppression of viral activity, which seems to be mainly related to the host's immune control and epigenetic factors. OBI is diffused worldwide, but its prevalence is highly variable among patient populations. This depends on different geographic areas, risk factors for parenteral infections, and assays used for HBsAg and HBV DNA detection. OBI has an impact in several clinical contexts: (a) it can be transmitted, causing a classic form of hepatitis B, through blood transfusion or liver transplantation; (b) it may reactivate in the case of immunosuppression, leading to the possible development of even fulminant hepatitis; (c) it may accelerate the progression of chronic liver disease due to different causes toward cirrhosis; (d) it maintains the pro-oncogenic properties of the "overt" infection, favoring the development of hepatocellular carcinoma.

Viral hepatitis: A narrative review of hepatitis A–E

Viral hepatitis continues to be a major health concern leading to hepatic decompensation ranging from acute hepatitis to cirrhosis and hepatocellular carcinoma. The hepatic and extrahepatic manifestations are not only debilitating but also associated with a significant economic burden. Over the last two decades, the field of virology has made significant breakthroughs leading to a better understanding of the pathophysiology of viral hepatitis, which in turn has led to new therapeutic options. The advent of direct-acting antiviral agents changed the landscape of hepatitis C virus (HCV) therapy, and new drugs are in the pipeline for chronic hepatitis B virus (HBV) treatment. There has also been a significant emphasis on screening and surveillance programs, widespread availability of vaccines, and linkage of care. Despite these efforts, significant gaps persist in care, and there is a pressing need for increased collaboration and teamwork across the globe to achieve a reduction of disease burden and elimination of HBV and HCV.

Update on the association of hepatitis B with intrahepatic cholangiocarcinoma: Is there new evidence?

Intrahepatic cholangiocarcinoma (iCCA) is a subgroup of cholangiocarcinoma that accounts for about 10%-20% of the total cases. Infection with hepatitis B virus (HBV) is one of the most important predisposing factors leading to the formation of iCCA. It has been recently estimated based on abundant epidemiological data that the association between HBV infection and iCCA is strong with an odds ratio of about 4.5. The HBV-associated mechanisms that lead to iCCA are under intense investigation. The diagnosis of iCCA in the context of chronic liver disease is challenging and often requires histological confirmation to distinguish from hepatocellular carcinoma. It is currently unclear whether antiviral treatment for HBV can decrease the incidence of iCCA. In terms of management, surgical resection remains the mainstay of treatment. There is a need for effective treatment modalities beyond resection in both first- and second-line treatment. In this review, we summarize the epidemiological evidence that links the two entities, discuss the pathogenesis of HBV-associated iCCA, and present the available data on the diagnosis and management of this cancer.

The Asian Pacific Association for the Study of the Liver clinical practice guidelines for the diagnosis and management of metabolic associated fatty liver disease

Metabolic associated fatty liver disease (MAFLD) is the principal worldwide cause of liver disease and affects nearly a quarter of the global population. The objective of this work was to present the clinical practice guidelines of the Asian Pacific Association for the Study of the Liver (APASL) on MAFLD. The guidelines cover various aspects of MAFLD including its epidemiology, diagnosis, screening, assessment, and treatment. The document is intended for practical use and for setting the stage for advancing clinical practice, knowledge, and research of MAFLD in adults, with specific reference to special groups as necessary. The guidelines also seek to improve patient care and awareness of the disease and assist stakeholders in the decision-making process by providing evidence-based data. The guidelines take into consideration the burden of clinical management for the healthcare sector.

Cryptic HBV Replicative Activity Is Frequently Revealed in Anti-HBc-Positive/HBsAg-Negative Patients with HIV Infection by Highly Sensitive Molecular Assays, and Can Be Predicted by Integrating Classical and Novel Serological HBV Markers

The anti-HBc-positive/HBsAg-negative status is frequent in HIV-infection and correlates with poor survival. Here, by highly-sensitive assays, we evaluate cryptic HBV replication and factors correlated with its detection in 81 anti-HBc-positive/HBsAg-negative HIV-infected patients. Patients were treated for >12 months with HBV-active modern combined antiretroviral-therapy (cART) and had serum HBV-DNA < 20 IU/mL by commercial Real-Time PCR. Serum HBV-DNA was quantified by droplet digital PCR, serum HBV-RNA by an Abbott research assay, and anti-HBc titer (proposed to infer intrahepatic cccDNA) by Lumipulse/Fujirebio. Cryptic serum HBV-DNA was detected in 29.6% of patients (median (IQR): 4(1-15) IU/mL) and serum HBV-RNA in 3.7% of patients despite HBsAg-negativity and HBV-active cART. Notably, cryptic serum HBV-DNA correlated with an advanced CDC-stage (p = 0.01) and a lower anti-HBs titer (p = 0.05), while serum HBV-RNA correlated with lower nadir CD4+ cell-count (p = 0.01). By analyzing serological HBV-markers, the combination of anti-HBs < 50 mIU/mL (indicating lower immune response) plus anti-HBc > 15COI (reflecting higher HBV replicative activity) was predictive of cryptic serum HBV-DNA (OR: 4.7(1.1-21.7), p = 0.046, PPV = 62.5%, and NPV = 72%). In conclusion, cryptic HBV-replication (not detected by classical assays) characterizes a conspicuous set of anti-HBc-positive HIV-infected patients despite HBsAg-negativity and HBV-active combined antiretroviral therapy (cART). The integration of classical and novel markers may help identify patients with cryptic HBV-replication, thus optimizing the monitoring of anti-HBc-positive/HBsAg-negative HIV-infected patients.

Antiviral therapy for the sexually transmitted viruses: recent updates on vaccine development

INTRODUCTION

The sexually transmitted infections (STIs) caused by viruses including human T cell leukemia virus type-1 (HTLV-1), human immunodeficiency virus-1 (HIV-1), human simplex virus-2 (HSV-2), hepatitis C virus (HCV), hepatitis B virus (HBV), and human papillomavirus (HPV) are major public health issues. These infections can cause cancer or result in long-term health problems. Due to high prevalence of STIs, a safe and effective vaccine is required to overcome these fatal viruses.

AREAS COVERED

This review includes a comprehensive overview of the literatures relevant to vaccine development against the sexually transmitted viruses (STVs) using PubMed and Sciencedirect electronic search engines. Herein, we discuss the efforts directed toward development of effective vaccines using different laboratory animal models including mice, guinea pig or non-human primates in preclinical trials, and human in clinical trials with different phases.

EXPERT OPINION

There is no effective FDA approved vaccine against the sexually transmitted viruses (STVs) except for HBV and HPV as prophylactic vaccines. Many attempts are underway to develop vaccines against these viruses. There are several approaches for improving prophylactic or therapeutic vaccines such as heterologous prime/boost immunization, delivery system, administration route, adjuvants, etc. In this line, further studies can be helpful for understanding the immunobiology of STVs in human. Moreover, development of more relevant animal models is a worthy goal to induce effective immune responses in humans.

Serological markers and molecular analysis of hepatitis B infection in a tertiary care hospital at Kathmandu, Nepal

AIM

To analyze the serology and molecular markers of the hepatitis B-infected patients from the tertiary care hospital at Kathmandu in Nepal.

METHODS

A total of 399 blood samples of patients from Sukraraj Tropical and Infectious Disease Hospital, Teku, Kathmandu, were collected. Samples were tested for HBsAg, HBeAg, and IgM anti-HBc using ELISA method. The samples were further categorized as acute and chronic. The genotyping was performed by real-time polymerase chain reaction (real-time PCR) and further validated by sequencing.

RESULTS

Out of 399 samples that were collected, 271 and 128 samples were acute and chronic cases respectively. Fifty-six samples were genotyped by qPCR, out of which 40 samples belonged to genotype D, 4 to C/D recombinant, 5 to genotype C, 3 to genotype B, and 4 were genotype A respectively. From these, 15 samples were used for sequencing of P (polymerase) gene and S (surface) genes. Thus, obtained sequences were used to construct neighbor-joining tree using Tamura-Nei model evolution and further validated by Bayesian analysis. A total of four sub-genotypes namely A1, C1, D1, and D5 were detected.

CONCLUSION

Hepatitis B virus infection is a global health problem affecting about 257 million people worldwide. In Nepal, there are few reports on the molecular and phylogenetic analysis of this virus. In this study, we report the circulation of seropositive occult hepatitis as well as CD-recombinant genotype in Nepalese population.

Silencing of HIF-1α inhibited the expression of lncRNA NEAT1 to suppress development of hepatocellular carcinoma under hypoxia

BACKGROUND

We aimed to explore the relationship between hypoxia-inducible factors-1α (HIF-1α) and lncRNA nuclear-enriched abundant transcript 1 (NEAT1), and their functions on hepatocellular carcinoma (HCC) under hypoxia.

METHODS

HIF-1α and NEAT1 levels in HCC tissues and corresponding non-tumor tissues were determined by qRT-PCR, and the correlations of their levels in HCC tissues were analyzed by Pearson test. The relationship between overall survival and the two genes (HIF-1α and NEAT1) for HCC patients was detected by log-rank test. Clinicopathological features of NEAT1 in HCC patients were collected. HIF-1α and NEAT1 levels in HCC cells were measured by qRT-PCR and Western blot, and their relationship was determined by co-immunoprecipitation (Co-IP) assay. Cell viability, migration and invasion were detected by CCK-8, scratch wound healing and transwell assay, respectively. The interaction of NEAT1 with HIF-1α in tumor development was determined by xenograft tumor assays in nude mice.

RESULTS

NEAT1 and HIF-1α were highly expressed and showed a positive relationship in HCC tissues, and specifically, higher NEAT1 expression was positively associated with advanced TNM stage and metastasis in HCC patients. Up-regulated NEAT1 or HIF-1α in HCC patients had poorer prognosis. NEAT1 was induced by HIF-1α and suppressed by siHIF-1α. NEAT1 overexpression further promoted development of HCC under hypoxia while promoting cell viability, migration and invasion and suppressing apoptosis, and such effects were reversed by down-regulating HIF-1α. NEAT1 overexpression promoted tumor growth, which was reversed by down-regulating HIF-1α.

CONCLUSION

HIF-1α knockdown inhibits NEAT1 expression, which suppresses progression of HCC and improves its prognosis.

Viral miRNAs as Active Players and Participants in Tumorigenesis

The theory that viruses play a role in human cancers is now supported by scientific evidence. In fact, around 12% of human cancers, a leading cause of morbidity and mortality in some regions, are attributed to viral infections. However, the molecular mechanism remains complex to decipher. In recent decades, the uncovering of cellular miRNAs, with their invaluable potential as diagnostic and prognostic biomarkers, has increased the number of studies being conducted regarding human cancer diagnosis. Viruses develop clever mechanisms to succeed in the maintenance of the viral life cycle, and some viruses, especially herpesviruses, encode for miRNA, v-miRNAs. Through this viral miRNA, the viruses are able to manipulate cellular and viral gene expression, driving carcinogenesis and escaping the host innate or adaptive immune system. In this review, we have discussed the main viral miRNAs and virally influenced cellular pathways, and their capability to drive carcinogenesis.

Hepatitis viruses take advantage of traditional practices to increase the burden of hepatocellular carcinoma in Tunisia

Hepatocellular carcinoma (HCC) is a major public health issue in Africa. In Tunisia, hepatitis B virus (HBV) is known to be an important risk factor for HCC in the south of the country, but the role played by hepatitis C virus (HCV) still remains unclear. The aim of the current case-control study was to identify risk factors for HCC development in the northern part of the country. Clinical and biological data including viral hepatitis status (serological and molecular) and non-infectious risk factors from 73 patients with HCC and 70 control subjects without hepatic diseases were collected. The mean age of the patients was 63 ± 10 years, and the ratio of males to females was 1.1. HCC occurred in cirrhotic liver in 72.0% of the cases. HCV infection was the dominant risk factor (64.3% of cases); the presence of HBV was observed in 53.4% of the cases. Occult hepatitis B and C were implicated, respectively, in 30.1% and 9.6% of the cases. HCV genotype 1b was predominant. Patients originating from western Tunisia formed a homogeneous group, characterized by significantly higher rates of tattoos or scarifications (83%) and HCV infection (80%) than those from other parts of the country. Chronic HCV infection is currently the primary risk factor for HCC in Tunisia; HBV infection remains frequent in its overt or occult infection forms. Traditional esthetic practices apparently contribute to increasing the burden of terminal liver diseases in western Tunisia.

Free episomal and integrated HBV DNA in HBsAg-negative patients with intrahepatic cholangiocarcinoma

There is evidence that chronic hepatitis B virus (HBV) infection is associated with an increased risk of intrahepatic cholangiocarcinoma (ICC) development, and it has been hypothesized an etiological role of HBV in the development of this tumor. Very little is known about occult HBV infection (OBI) in ICC. Aims of the study were to investigate the OBI prevalence and to characterize the HBV molecular status at intrahepatic level in OBI-positive cases with ICC.

Frozen liver tumor specimens from 47 HBV surface-antigen-negative patients with ICC and 41 paired non-tumor liver tissues were tested for OBI by 4 different HBV-specific nested PCR. Covalently closed circular HBV DNA (HBV cccDNA) and viral integrations were investigated in OBI-positive cases.

HBV DNA was detected in tumor and/or non-tumor specimens from 29/47 (61.7%) ICC patients. HBV cccDNA was found in tissues from 5/17 (34.5%) cases examined. HBV integration was detected in 4/10 (40%) tumor tissues tested and involved HBx and HBV-core gene sequences in 3 and 1 cases, respectively. Viral integration occurred: (a) 9,367 nucleotides upstream of the cat-eye-syndrome critical region protein-5-isoform coding sequence; (b) within the cystinosin isoform-1-precursor gene; (c) within the thromboxane-A-synthase-1 gene; (d) within the ATPase phospholipid transporting 9B gene.

Occult HBV infection is highly prevalent in patients with ICC. Both free viral genomes and integrated HBV DNA can be present in these cases. These results suggest an involvement of HBV in the carcinogenic process leading to ICC development even in cases with occult infection.

Clinicopathological study of occult hepatitis B virus infection in hepatitis C virus-associated hepatocellular carcinoma

BACKGROUND

Occult hepatitis B virus infection (OBI) frequently occurs in patients with chronic hepatitis C (CHC) infection, but the influence of OBI on CHC outcome is still uncertain. The aim of the present study was to clarify the clinical and pathological characteristics of OBI in CHC-related hepatocellular carcinoma (HCC).

PATIENTS AND METHODS

DNA was obtained from serum and tumor tissue of patients with hepatitis C virus (HCV)-related HCC with negative HBsAg and from patients with HCV-related liver cirrhosis. HBV-DNA was detected using qPCR. Clinicopathological features were compared between patients with HCC with and without OBI.

RESULTS

On the basis of positive serum and tissue HBV-DNA typing, the overall frequency of OBI was 50% in patients with HCV-related HCC. HBV genotype D was the most dominant, constituting 35.3% of HCC cases. Almost 80% of patients with OBI had anti-HBc, whereas 20% of patients had no serological markers. Tissue HBV-DNA showed significant association with positive serum HBV-DNA, anti-HBc, and genotype D. There were no clinical differences between patients with HCC with and without OBI; however, patients with OBI tended to be younger. HCC cases with positive OBI were significantly associated with positive anti-HBc antibodies and late histological grades (3-4). Multivariate logistic regression analysis revealed that the presence of OBI was a predictor of more advanced HCC histological grades in patients with HCV infection.

CONCLUSION

OBI was detected in 50% of HCV-infected patients with HCC. OBI was strongly associated with the presence of anti-HBc antibodies. Patients with HCC with positive OBI were younger and had more advanced HCC histological grades.

What Comes First: Treatment of Viral Hepatitis or Liver Cancer?

Chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infection are the most important underlying causes for the development of hepatocellular carcinoma (HCC) worldwide. Determining the optimal approach for management of the viral infection and the HCC depends on the virus and the stage of the cancer. In patients with HCV-associated HCC, there are multiple reasons to first treat the HCC. Firstly, in case of a curable HCC, the urgency for HCC treatment is important to avoid progression during HCV treatment. Secondly, the presence of HCC itself appears to reduce the rates of sustained virological response (SVR) achieved with direct-acting antivirals (DAAs). And finally, the evidence does not support the concept of an increase in HCC recurrence due to DAAs, so a patient can safely be treated after HCC cure. For patients with very advanced HCC, the benefits of HCV therapy are questionable. In contrast, those who develop HCC in the setting of chronic HBV infection, treatment with nucleoside analogues (NAs) is recommended prior to treating HCC, to prevent further liver injury and reduce the risk for HCC recurrence. Ultimately, earlier diagnosis and treatment of HBV and HCV will hopefully reduce the incidence of HCC worldwide.

Hepatocellular carcinoma: Clinical-pathological features and HIV infection in Mozambican patients<sup/>

BACKGROUND AND AIMS

Mozambique had been ranked among the countries with the highest global incidence of HCC with chronic hepatitis B infection and high exposure to aflatoxin-B1 (AFB1) being major risk factors. Indeed, HCC remains one of the most frequent cancer in Maputo. On the other hand, Mozambique has a high prevalence of infection with Human Immunodeficiency virus (HIV). Our study aims to describe the epidemiology, clinicopathological and serological features of patients with HCC in Maputo Central Hospital and its relationship with HIV.

METHODS

A series of 206 patients, diagnosed with HCC via fine needle aspiration, were consecutively included in the study. Patient data was collected using a questionnaire and all patients were tested for HBV, HCV, HIV.

RESULTS

Median age was 49 years old and the M: F sex ratio was 2.4. A total of 114 (56.2%) of the patients were HBsAg positive. Hepatitis C antibodies were present in 8.9% of cases, and co-infection with HBV and HCV (HBsAg/anti-HCV) was observed in 4 (2.0%) cases. The remainder, 36.3%, were neither hepatitis B- nor C-related. HIV was detected in 34 cases (18.0%) cases. HIV-HBV or HIV-HCV co-infections were observed in 22 (68.8%) and 2 (6.2%) cases. Overall, positivity for HIV was associated with younger age, and especially in patients with HBsAg+/anti-HCV+.

CONCLUSIONS

Our data emphasize the need for a reinforcement of secondary prevention measures in Mozambique. Serological screening for HBV in people born before universal anti-hepatitis B immunization (2001), effective screening, and specific management in HIV(+) patients are urgently needed.

Does persistent anti-HBc positivity influence the prognosis of HBsAg-negative hepatocellular carcinoma? comparative outcomes of anti-Hbc positive versus anti-Hbc negative non-B non-C HCC

BACKGROUND

To compare the presentations and outcomes of anti-HBc seropositive Hepatocellular Carcinoma (HBc-HCC) with anti-HBc seronegative (NHBc-HCC) patients in HBsAg negative Non-HBV Non-HCV (NBNC-HCC) HCC population.

METHODS

515 newly diagnosed HCC patients from January 2011 to September 2016 were retrospectively reviewed. 145 (66.5%) NHBc-HCC and 73 (33.5%) HBc-HCC patients were identified. Patient demographics, disease characteristics, details of treatments, recurrence and survival outcomes were analysed.

RESULTS

A significantly lower proportion of HBc-HCC patients were diagnosed through surveillence (6.8% vs 26.2%, p = 0.001). HBc-HCC patients were less likely cirrhotic (p < 0.001), portal hypertensive (p < 0.001), ascitic (p = 0.008) and thrombocytopenic (p = 0.003). A higher proportion of HBc-HCC patients had treatment with curative intent (46.6% vs 30.3%, p = 0.018) and surgery (39.7% vs 16.6%, p < 0.001). Although HBc-HCC patients had larger median tumor size (74.0 mm vs 55.0 mm, p = 0.016) with a greater proportion of patients having tumors ≥5 cm, there was no difference in the overall median survival (19.0 months vs 22.0 months, p = 0.919) and recurrence rates (38.2% vs 40.9%).

CONCLUSION

Isolated anti-HBc seropositivity in HbsAg negative patients tend to present incidentally with delayed diagnoses resulting in larger tumors, but their long-term survival remain comparable.

Naturally Occurring Hepatitis B Virus Mutations Leading to Endoplasmic Reticulum Stress and Their Contribution to the Progression of Hepatocellular Carcinoma

Hepatitis B virus (HBV) infection is a global health problem that causes a wide range of pathological outcomes, including cirrhosis and hepatocellular carcinoma (HCC). Endoplasmic reticulum (ER) stress induction by HBV infection has been implicated in liver carcinogenesis and disease progression with chronic inflammation via enhanced inflammation, oxidative stress-mediated DNA damage, and hepatocyte proliferation. In the natural course of HBV infection, the accumulation of naturally occurring mutations in the HBV genome can generate several mutant types of HBV-encoded proteins, including three different proteins in the S ORF (SHBs, MHBs, and LHBs) and HBcAg in the C ORF, which could contribute to enhanced ER stress in infected hepatocytes mainly via increased ER accumulation of mutant proteins. However, it seems that there may be distinct capacity and pathway in ER stress-induction and distinct resulting clinical outcomes between HBV variants. In addition, the role of HBxAg mutations in ER stress remains unknown. However, it has been reported that HBxAg itself could exert ER stress in infected cells, resulting in HCC generation in chronic HBV patients. To date, review papers regarding ER stress-mediated HBV mutation have been limited into a specific mutation type: preS2 deletion. So, in this review, we will discuss details about various mutation types in all four regions of the HBV genome (preS1, preS2, S, and C) related to ER stress and their distinct ER stress mechanisms and clinical outcomes in terms of mutation types.

Occult HBV infection status and its impact on surgical outcomes in patients with curative resection for HCV-associated hepatocellular carcinoma

Background

We sought to clarify the prevalence of occult hepatitis B virus (HBV) infection (OBI) and to determine whether OBI affects the surgical outcomes in curatively resected Japanese patients with hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC).

Methods

A total of 257 patients with HCV-related HCC who underwent curative surgical resection were enrolled. All enrolled patients were serologically negative for HBV surface antigen and positive for HCV antibody. DNA was extracted from formalin-fixed paraffin-embedded liver tissue. OBI was determined by the HBV-DNA amplification of at least two different sets of primers by TaqMan real-time polymerase chain reaction. Surgical outcomes were evaluated according to overall survival (OS), disease-specific survival (DSS), and disease-free survival (DFS).

Results

OBI was identified in 15 of the 257 (5.8%) cases. In the multivariate analyses, the factors significantly correlated with OS were BMI >25 (P=0.0416), portal vein invasion (P=0.0065), and multiple tumors (P=0.0064). The only factor significantly correlated with DSS was T-stage (P=0.0275). The factors significantly correlated with DFS were liver fibrosis (P=0.0017) and T-stage (P=0.0001). The status of OBI did not show any significant correlation with OS, DSS or DFS, but a weak association with DSS (P=0.0603) was observed.

Conclusions

The prevalence of OBI was 5.8% in 257 cases of HCV-related HCC. Although a weak association between DSS and OBI was observed, and statistical analyses were limited by small number of OBI cases, no significant correlation between OBI and surgical outcomes was detected.

HBV Upregulates CtBP2 Expression via the X Gene

Background

Hepatitis B virus (HBV) infection causes acute and chronic liver diseases that can eventually develop into cirrhosis and hepatocellular carcinoma (HCC), but the carcinogenesis of HBV is not fully understood. Carboxyl-terminal-binding protein 2 (CtBP2) plays an important role in tumorigenesis and progression. The aim of this study was to investigate the effect of HBV on CtBP2 expression and to explore its mechanism.

Methods

Real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) and western blotting were used to evaluate the CtBP2 mRNA and protein expression levels in tissues and cells. The HBV infectious clone pHBV1.3 and plasmids expressing a single gene of the HBV genome were cotransfected with the CtBP2 gene promoter pGL3-CtBP2 into the human hepatoma cell line HepG2, and luciferase activity was determined using a luminometer.

Results

CtBP2 expression was higher in HBV-related HCC tissues than in paracancerous tissues. CtBP2 expression was higher in HepG2.2.15 cells integrated with the HBV genome than in HepG2 cells. pHBV1.3 upregulated CtBP2 mRNA and protein expression. The HBV X gene significantly activated CtBP2 gene promoter activity, and CtBP2 mRNA and protein expression were upregulated by the HBV X gene. This activation effect was enhanced by the increase in the dose of the X gene, showing metrological dependence.

Conclusion

HBV may be involved in the occurrence and development of HCC by upregulating CtBP2 expression.

Occult hepatitis B virus infection and surgical outcomes in non-B, non-C patients with curative resection for hepatocellular carcinoma

AIM

To investigate the prevalence, clinicopathological characteristics and surgical outcomes of occult hepatitis B virus (HBV) infection (OBI) in patients with non-B, non-C (NBNC) hepatocellular carcinoma (HCC).

METHODS

This study retrospectively examined the cases of 78 NBNC patients with curative resection for HCC for whom DNA could be extracted from formalin-fixed paraffin-embedded tissue. OBI was determined by the HBV-DNA amplification of at least two different sets of primers by TaqMan real-time polymerase chain reaction. Possibly carcinogenetic factors such as alcohol abuse, diabetes mellitus, obesity and non-alcoholic steatohepatitis (NASH) were examined. Surgical outcomes were evaluated according to disease-free survival (DFS), overall survival (OS) and disease-specific survival (DSS).

RESULTS

OBI was found in 27/78 patients (34.6%) with NBNC HCC. The OBI patients were significantly younger than the non-OBI cases at the time of surgery (average age 63.0 vs 68.1, P = 0.0334) and the OBI cases overlapped with other etiologies significantly more frequently compared to the non-OBI cases (P = 0.0057). OBI had no impact on the DFS, OS or DSS. Only tumor-related factors affected these surgical outcomes.

CONCLUSION

Our findings indicate that OBI had no impact on surgical outcomes. The surgical outcomes of NBNC HCC depend on early tumor detection; this reconfirms the importance of a periodic medical examination for individuals who have NBNC HCC risk factors.

Prevalence of occult hepatitis B virus infection and Torque teno virus infection and their association with hepatocellular carcinoma in chronic hepatitis C patients

BACKGROUND

The role of occult hepatitis B virus (HBV) infection and Torque teno virus (TTV) infection in the development of hepatocellular carcinoma (HCC) in chronic hepatitis C patients is still uncertain.

AIM

The aim of the present study was to investigate the prevalence and significance of OBI and TTV infection, and to examine the genetic diversity of these viruses, in chronic hepatitis C patients with and without HCC.

METHODS

Sera from 151 hepatitis C virus (HCV)-infected patients (49 patients with HCC and 102 without HCC) negative for HBV surface antigen (HBsAg) were tested for the presence of OBI and TTV infection by semi-nested and group-specific multiplex PCR assays, respectively. Nucleotide sequencing of HBV S region was further performed.

RESULTS

OBI and TTV infection were detected in 5 (3.3%) and 68 (45%) patients, respectively. HBV isolates were classified into genotypes A (4/5, 80%) and D (1/5, 20%), and no HBsAg escape mutation was observed. TTV phylogenetic group 3 was the most prevalent among both HCC and non-HCC patients. OBI and TTV infection were significantly more frequent in patients with HCC than patients without HCC (p=0.003, and p=0.009, respectively). Moreover, TTV infection was associated with HCC (OR=2.23, 95%CI=1.04-4.80, p=0.040), independently of liver cirrhosis.

CONCLUSIONS

A low prevalence of OBI was observed in patients with HCV-related chronic liver disease, and TTV infection was an independent factor associated with the occurrence of HCC. Whether TTV influences the progression of liver disease in chronic hepatitis C patients remains to be elucidated.

Hepatitis B virus reactivation after heart transplant: Incidence and clinical impact

BACKGROUND

Occult hepatitis B infection consists of persistence of HBV genomes in hepatocytes,absence of serum HBsAg, low/undetectable serum HBVDNA. Reactivation of HBV infection may occur during immunosuppression, but few data are available in heart transplant.

OBJECTIVES

We followed-up heart recipients with or without markers of previous HBV infection,evaluating prevalence of HBV markers, incidence of HBV reactivation and its virological and clinical features.

STUDY DESIGN

Heart failure patients listed for heart transplant (2007-2013) were screened for current or past HBV infection. Transplanted patients with past HBV infection (anti-HBc+/±anti-HBs+/HBVDNA-) were followed up as cases, and an equal number of HBV negative patients as controls. Virological reactivation was detected by standard real-time and home-made highly sensitive PCR (surface/core HBVDNA regions). Clinical status and progression were assessed by liver histology, ultrasound or elastography.

RESULTS

67 patients underwent heart transplant, including 4 (5.9%) HBsAg+ subjects. Cases were 11/67 (16.4%). During a median follow-up of 30 months, only one of these 11 patients presented viral reactivation (HBVDNA 209IU/mL) at month 22, and started antiviral treatment. Four other recipients showed virological events of uncertain significance (sensitive PCR-only intermittently positive). Clinical signs of liver disease were observed in only one case at the last follow-up. A nonsignificant difference in survival was observed between cases and all other heart recipients without prior HBV contact (death rate 5/11 vs 15/52, respectively; p=0.097).

CONCLUSIONS

HBV genotypic reactivation in HBsAg-/anti-HBc+/HBVDNA- heart recipients is uncommon. Virological events of uncertain significance occur more frequently; their clinical impact seems to be negligible.

Contribution of hepatitis B virus and hepatitis C virus to liver cancer in China north areas: Experience of the Chinese National Cancer Center

INTRODUCTION

The aim of this study was to determine the impact of hepatitis B virus (HBV) and/or hepatitis C virus (HCV) on primary liver cancer (PLC) in China north areas.

METHODS

A total of 2172 histologically confirmed PLC patients attending the National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences during the period January 1, 2003 to December 31, 2014 were enrolled. Details of hepatitis B surface antigen (HBsAg), antibodies against HBV core antigen (anti-HBc), and antibodies against HCV (anti-HCV) status were recorded. Sequencing of the HBV PreS-S gene and the C/E1 and NS5B fragments of HCV was performed and the genotypes were analyzed for some of the patients with hepatocellular carcinoma (HCC).

RESULTS

Among the 2172 histologically confirmed PLC cases, 1823 (83.9%) had HCC and 238 (11.0%) had intrahepatic cholangiocarcinoma (iCCA). Among HCC cases, HBV infection alone, indicated by HBsAg-neg/pos+anti-HBc-pos, was found in 1567 (86.0%) cases; of these, 18.2% (331/1823) were HBsAg-neg+anti-HBc-pos. Serum HBV-DNA was detectable in 70% of HBsAg-neg+anti-HBc-pos HCC cases. The dominant HBV genotype was HBV-C2 (94.4%). HCV infection alone, indicated by anti-HCV-pos, was found in 2.5% (46/1823) of cases; HCV-1b (72.1%) was the dominant genotype. HBV+HCV co-infection markers were found in 6.7% (122/1823) of cases. Only 88 (4.8%) cases had no HBV and no HCV markers. Among the 238 iCCA cases, 54 (22.7%) were HBsAg-pos+anti-HBc-pos; none was anti-HCV-pos alone.

CONCLUSIONS

HBV remains the major contributor to PLC in China north areas Individuals with occult HBV infection should not be ignored in liver cancer screening.

Risk factors for non-alcoholic fatty liver disease are common in patients with non-B non-C hepatocellular carcinoma in India

AIM OF THE STUDY

The aim of the study was to analyze the prevalence of risk factors for non-alcoholic fatty liver disease (NAFLD) in patients with non-B non-C hepatocellular carcinoma (HCC).

METHODS

Between June 2012 and November 2014, patients with HCC, negative for hepatitis B surface antigen and hepatitis C virus antibody, were included in this study. All patients were assessed for risk factors for NAFLD such as diabetes mellitus (DM), hypertension, dyslipidemia, metabolic syndrome, and obesity.

RESULTS

Forty-seven patients with non-B non-C HCC (males, 37; age, 60±10 years; mean±SD) were studied. Model for end-stage liver disease score was 11±4. Twenty-five patients were in Child's class A. History of significant alcohol intake was noted in 11 (23%) patients. Prevalence of risk factors for NAFLD were obesity 24 (51%), DM 22 (47%), metabolic syndrome 21 (45%), hypertension 16 (34%), and dyslipidemia 13 (28%). Forty (85%) patients had at least one risk factor for NAFLD. The mean duration of at least one NAFLD risk factor was 7.5 years, prior to diagnosis of HCC. Thirteen (28%) patients were positive for anti-HBc; however, none of the study patients had detectable HBV DNA in blood.

CONCLUSIONS

Eighty-five percent of the patients with non-B non-C HCC had at least one risk factor for NAFLD. None of the study patients had occult hepatitis B infection. NAFLD is emerging as the major etiological contributing factor for non-B non-C HCC in India.

Chronic viral hepatitis and its association with liver cancer

Chronic infection with hepatitis viruses represents the major causative factor for end-stage liver diseases, including liver cirrhosis and primary liver cancer (hepatocellular carcinoma, HCC). In this review, we highlight the current understanding of the molecular mechanisms that drive the hepatocarcinogenesis associated with chronic hepatitis virus infections. While chronic inflammation (associated with a persistent, but impaired anti-viral immune response) plays a major role in HCC initiation and progression, hepatitis viruses can also directly drive liver cancer. The mechanisms by which hepatitis viruses induce HCC include: hepatitis B virus DNA integration into the host cell genome; metabolic reprogramming by virus infection; induction of the cellular stress response pathway by viral gene products; and interference with tumour suppressors. Finally, we summarise the limitations of hepatitis virus-associated HCC model systems and the development of new techniques to circumvent these shortcomings.

Cell surface N-glycan alteration in HepAD38 cell lines expressing Hepatitis B virus

Hepatitis B virus (HBV) is the smallest partially double-stranded DNA virus known to infect humans. Worldwide, more than 50% of hepatocellular carcinoma (HCC) cases are related to chronic Hepatitis B. Development of HCC from normal liver cells is characterized by changes in cell surface N-glycans, which can promote the invasive behavior of tumor cells, leading ultimately to the progression of cancer. However, little is understood about the cell surface N-glycans of HBV-infected liver cells. We try to address this by taking advantage of the HepAD38 cell line, which can replicate HBV in the absence of tetracycline [tet(-)] in growth medium. In the presence of tetracycline [tet(+)], this cell line is free from the virus due to the repression of pregenomic (pg) RNA synthesis. In culture medium without tetracycline, cells express viral pgRNA and start to secrete virions into the supernatant. Here we studied the expression of glycosyltransferases and the cell surface N-glycan composition of tet(+) and tet(-) HepAD38. Among the glycosyltransferases upregulated by the expression of HBV were GnT-II, GnT-IVa, ST6Gal1, and GnT-V, whereas GnT-I, GnT-III, β4GalT1, and FUT8 were downregulated. About one-third of the total cell surface N-glycans found on tet(-)HepAD38 were sialylated. As for tet(+)HepAD38, sialylation was 6% lower compared to the tet(-) cells. Neither treatment changed the cell surface N-glycans expression of the total complex type or the total fucosylated type, which were about 50% or 60%, respectively. Our results showed that the expression of HBV triggers higher sialylation in HepAD38 cells. Altogether, the results show that HBV expression triggered the alteration of the cell surface N-glycosylation pattern and the expression levels of glycosyltransferases of HepAD38 cells.

Hepatitis B virus X protein increases microRNA‑21 expression and accelerates the development of hepatoma via the phosphatase and tensin homolog/phosphoinositide 3‑kinase/protein kinase B signaling pathway

Hepatitis B virus (HBV) X protein (HBx) is a key regulatory protein that is involved in HBV infection, replication and carcinogenesis of hepatocellular carcinoma (HCC). The aim of the present study was to investigate the role of HBx in the progression and metastasis of liver cancer cells and to determine the underlying molecular mechanism of HBx in metastatic liver cancer cells. HBx protein expression was detected by western blot analysis, and microRNA (miR)‑21 levels were determined by reverse transcription‑quantitative polymerase chain reaction in the highly metastatic MHCC‑97H low metastatic MHCC‑97L and SMMC‑7721 liver cancer cell lines. The results demonstrated that the levels of HBx and miR‑21 were significantly increased in MHCC‑97H cells compared with MHCC‑97L and SMMC‑7721 cells. In addition, three pairs of small interfering (si)RNA specific to HBx were designed and synthesized to interfere with endogenous HBx in liver cancer cells, and the results demonstrated that knockdown HBx was associated with a corresponding decrease in miR‑21 expression. The MTT assay results demonstrated that cell viability significantly decreased in HBx‑siRNA cells compared with scramble siRNA‑transfected cells. In addition, transfection with an miR‑21 inhibitor inhibited MHCC‑97H cell proliferation. Furthermore, Transwell assay results revealed that downregulation of HBx and treatment with miR‑21 inhibitors contributed to the inhibition of MHCC‑97H cell invasion and metastasis. Western blot analysis demonstrated that miR‑21 inhibitors and HBx‑siRNA treatment led to the upregulation of phosphatase and tensin homolog (PTEN), and decreased levels of phosphoinositide 3‑kinase (PI3K), phosphorylated protein kinase B (Akt) and matrix metalloproteinase (MMP)‑2. The results of the present study indicated that HBx was positively associated with miR‑21 expression, and downregulation of miR‑21 and HBx suppressed MMP‑2 activity via the PTEN/PI3K/Akt signaling pathway. Therefore, HBx and miR‑21 may represent novel therapeutic targets for the treatment of HCC.

[Clinical and morphological correlations in occult hepatitis B]

Occult hepatitis B (ОHB) characterized by the absence of blood HBsAg attracts the attention of specialists of different profiles; however, its clinical morphological aspects have not been practically studied.

AIM

to estimate the proportion of OHB in the structure of fatal outcomes in chronic viral hepatitis (CVH) and to characterize its clinical course and structural changes on autopsy materials.

MATERIAL AND METHODS

A total of 455 autopsy cases of CVH were examined for its etiology in the S.P. Botkin Clinical Hospital of Infectious Diseases in 2014-2016. An in-depth prospective clinical analysis was made to investigate 28 cases of OHB in the stage of decompensated liver cirrhosis, which had subsequently culminated in death. The criteria of inclusion were history data and clinical symptoms of CVH in the detection of markers for hepatitis A, C, and D and HIV in serum HBcAb in the absence of HBsAg. HBsAbs were also determined. Along with the traditional morphological examination, immunohistochemistry (IHC) for HBsAg and HBcAg was carried out.

RESULTS

There were 108 CVHB cases (23.7% of the total cases of CVH), including 77 OHB cases (71.3% of those of CVHB) while HBsAg was not determined. HBsAb-negative patients were more often observed to have clinical signs of jaundice (p<0.05) and skin itching (p<0.05). Dyspepsia and hemorrhagic manifestations prevailed in patients with HBsAb (more than 10 IU/l) (p<0.05). All the cases were found to have characteristic morphological signs of CVH, including intranuclear inclusions and nuclear polymorphism in 10.7% of deaths. There was an IHC-positive reaction to VHB antigens in 28.6% of the patients and a doubtful reaction in 25.0%.

CONCLUSION

Serum НВсAb may serve as a diagnostic marker for HBV infection. Clinical and morphological correlations enabled the authors to state that CVHB was present in all cases in the absence of serum HBsAg in the patients.

MOLECULAR-BIOLOGICAL MARKERS OF HEPATITIS В IN PATIENTS WITH LIVER FIBROSIS/CIRRHOSIS IN UZBEKISTAN

Aim. Evaluate prevalence of genetic variants of hepatitis В viruses in population of various regions of Uzbekistan with hepatitis of various genesis and different severity levels of liver fibrosis and cirrhosis. Materials and methods. Blood plasma and liver biopsy from 39 patients with different severity levels of liver fibrosis and cirrhosis served as study material. Genotyping based on direct sequencing of Pre-Sl/Pre-S2/S HBV DNA region was applied. Results. Hepatitis В virus was detected in 32 samples ofthe 39 provided, frequency of occurrence - 82%, respectively. Phylogenetic analysis has shown, that only genotype D was detected among the examined patients, hepatitis В virus subtype D1 predominated (84.38%) compared with D2 (3.12%) and D3 (12.5%) subtypes. Conclusion. Large-scale sequencing of HBV in Central Asia will allow to evaluate routes of transmission and time of evolutionary separation of virus isolates. Understanding the epidemiology of the infectious process is important for development of programs for prophylaxis and therapy of the infection.

Current hepatitis B virus infection situation in Indonesia and its genetic diversity

Indonesia has a moderate to high endemicity of hepatitis B virus (HBV) infection. The risk for chronic HBV infection is highest among those infected during infancy. Since 1997, hepatitis B (HepB) vaccination of newborns has been fully integrated into the National Immunization Program. Although HBV infection has been reduced by the universal newborn HepB immunization program, it continues to occur in Indonesia. The low birth dose coverage and the presence of vaccine escape mutants might contribute to this endemicity among children. Although limited information is available for an analysis of occult HBV infection (OBI), several variations and substitutions in the pre-S/S region have been detected in Indonesian HBV strains. Additionally, persistent infection and disease progression of chronic hepatitis B are related to not only viral factors but also the host genome. Indonesia is one of the most ethnically heterogeneous nations, with Javanese and Sundanese as the two highest ethnic groups. This multi-ethnicity makes genomic research in Indonesia difficult. In this article, we focused on and reviewed the following aspects: the current hepatitis B immunization program and its efficacy, OBI, HBV infection among high-risk patients, such as hemodialysis patients, and research regarding the host genome in Indonesia.

The Prevalence of SEN Virus and Occult Hepatitis B (OBI) Virus Infection Among Blood Donors in Ahvaz City

BACKGROUND

The SEN virus (SENV) is a prevalent blood borne pathogen that has a worldwide incidence. SENV is comprised of eight genotypes; genotypes H and D are frequently associated with the pathogenesis of non-A - E hepatitis and post-transfusion hepatitis in blood donors and hepatitis patients. So far, no SENV pathogenesis has been reported in the liver biopsies of SENV carriers, but the frequency of SENV and its related genotypes requires further molecular epidemiology studies in different regions of the world. Occult hepatitis B infection (OBI) is another global public health problem that is primarily transmitted via blood transfusions. Therefore, the identification of OBI among blood donors is key to preventing the spread of this disease. The relationship between SENV and OBI requires further evaluation.

OBJECTIVES

The aim of this study was to determine the prevalence of SENV-D and SENV-H in blood donors in Ahvaz city with a particular focus on co-infection with OBI.

PATIENTS AND METHODS

This study had a cross-sectional design and included 184 healthy consecutive blood donors who visited a blood transfusion center in Ahvaz city from October-November 2013. The sera of all blood donors negative for HBsAg, anti-HCV antibody, and anti-HIV antibody were tested for SENV-D and SENV-H using nested polymerase chain reaction (PCR). In addition, tests for HBV DNA (PCR), HBcIgG (ELISA), liver function (aspartate transaminase and alanine transaminase), and alkaline phosphatase were carried out.

RESULTS

Liver function tests in the healthy blood donors were within the normal range. The incidence rates of SENV-D and SENV-H in the 184 total blood donors were 10 (5.4%) (95% confidence interval (CI): 2.1% - 9.0%) and 32 (17.4%) cases (95% CI: 12.0% - 23.0%), respectively. SENV-H/D co-infection occurred in 2 (1.1%) patients. The sera of 8/184 (4.3%) were positive for anti-HBc antibody but negative for HBV DNA.

CONCLUSIONS

Regardless of the presence of nonpathogenic SENV, 44/184 (24%) blood donors tested positive for both SENV-D and SENV-H. Although 4.3% of blood donors were positive for HBcIgG but negative for HBV DNA, the presence of OBI cannot be ruled out unless their liver biopsies show negative for HBV DNA.

Natural regression of fibrosis in chronic hepatitis B

The fibrosis of liver cirrhosis was considered to be irreversible before the anti-viral drugs showed that it is reversible when they lead to continuous suppression of viral replication and inflammation. However, several reports previously showed that fibrosis of type B liver cirrhosis was almost completely absorbed after the natural remission of chronic inflammation. This phenomenon might not be limited to exceptional patients, but rather occur commonly, considering the dynamic clinical features of chronic hepatitis B (CHB), where inactive carrier stage normally follows aggravation of hepatitis and progression of fibrosis at the time of HBeAg seroconversion. Thus, fibrosis levels of CHB as a hepatocellular carcinoma (HCC)-surveillance marker, particularly those of the inactive stage, could be underestimated, because some of them might have been (pre)cirrhotic in the past and recovered with the natural regression of fibrosis. We argue that cirrhosis-induced HCC mechanisms, rather than direct action of viral genome, may be more common than generally considered in CHB patients. This may have some impact on reconsidering the surveillance rationale for HCC in CHB, from where advanced HCCs tended to be missed. In addition, a molecular marker to assess the cancer-prone characteristics of the liver will definitely be needed to resolve the issue.

Characterization of Novel Hepatitis B Virus PreS/S-Gene Mutations in a Patient with Occult Hepatitis B Virus Infection

Objective

The impact of hepatitis B virus (HBV) preS/S-gene mutations on occult HBV infection (OBI) is not fully understood. This study characterized multiple novel HBV preS/S-gene mutants obtained from an OBI patient.

Methods

PreS/S-gene mutants were analyzed by clonal sequencing. Viral replication and expression were analyzed by transfecting HBV genomic recombinants into HepG2 cells.

Results

Twenty-one preS/S-gene mutants were cloned from four sequential serum samples, including 13 mutants that were not previously documented: (1) sI/T126V+sG145R; (2) preS1 nt 3014−3198 deletion; (3) preS1 nt 3046−3177 deletion; (4) preS1 nt 3046−3177 deletion+s115−116 “INGTST” insertion; (5) preS1 nt 3046−3177 deletion+s115−116 “INGTST” insertion+sG145R; (6) preS1 nt 3115−3123 deletion+sQ129N; (7) preS1 nt 3115−3123 deletion+s126−127 “RPCMNCTI” insertion; (8) s115−116 “INGTST” insertion; (9) s115−116 “INGTST” insertion+sG145R; (10) s126−127 “RPCMNCTI” insertion; (11) preS1 nt 2848−2862 deletion+preS2 initiation codon M→I; (12) s122−123 “KSTGLCK” insertion+sQ129N; and (13) preS2 initiation codon M→I+s131−133TSM→NST. The proportion of preS1 nt 3046−3177 deletion and preS2 initiation codon M→I+s131−133TSM→NST mutants increased in the viral pool with prolonged disease. The 13 novel OBI-related mutants showed a 51.2−99.9% decrease in HBsAg levels compared with that of the wild type. Additional N-glycosylation-associated mutations, sQ129N and s131−133TSM→NST, but not s126−127 “RPCMNCTI,” greatly attenuated anti-HBs binding to HBsAg. Compared with the wild type, replication and surface antigen promoter II activity of the preS1 nt 3046−3177 deletion mutant decreased by 43.3% and 97.0%, respectively.

Conclusion

PreS/S-gene mutations may play coordinated roles in the presentation of OBI and might be associated with disease progression. This has implications for HBV diagnosis and vaccine improvement.

Chronic hepatitis B virus and hepatitis C virus infections and cancer: synergy between viral and host factors

Hepatitis B virus (HBV) or hepatitis C virus (HCV) infections represent major causes of chronic liver disease and hepatocellular carcinoma. Despite inducing shared pathological events leading to oncogenic transformation, these two viruses present profound differences in their molecular features, life cycle and interplay with host factors, which significantly differentiate the prognostic and therapeutic approach to the related diseases. In the present review, we report the main mechanisms involved in the multistep process leading from HCV/HBV infection and cancer development, discussing side-by-side the analogies and differences between the two viruses. Such events can be broadly categorized into (a) direct oncogenic effects, involving integration in the host genome (in the case of HBV) and chromosomal instability, interference with oncosuppressor pathways, induction of oxidative stress, promotion of angiogenesis, epithelial-mesenchymal transition, alterations in the epigenetic asset and interaction with non-coding RNAs; and (b) indirect activities mostly mediated by host events, including chronic inflammation sustained by peculiar cytokine networks (such as interleukin-6 and lymphotoxins), metabolic dysfunctions promoted by steatohepatitis, interplay with gut microbiota and fibrotic events (mainly in HCV infection). This scenario suggests that the integrated study of viral and host factors may lead to the successful development of novel biomarkers and targets for therapy.

Chronic hepatitis B: Virology, natural history, current management and a glimpse at future opportunities

The host immune system plays an important role in chronic hepatitis B (CHB), both in viral clearance and hepatocellular damage. Advances in our understanding of the natural history of the disease have led to redefining the major phases of infection, with the "high replicative, low inflammatory" phase now replacing what was formerly termed the "immune tolerant" phase, and the "nonreplicative phase" replacing what was formerly termed the "inactive carrier" phase. As opposed to the earlier view that HBV establishes chronic infection by exploiting the immaturity of the neonate's immune system, new findings on trained immunity show that the host is already somewhat "matured" following birth, and is actually very capable of responding immunologically, potentially altering future hepatitis B treatment strategies. While existing therapies are effective in reducing viral load and necroinflammation, often restoring the patient to near-normal health, they do not lead to a cure except in very rare cases and, in many patients, viremia rebounds after cessation of treatment. Researchers are now challenged to devise therapies that will eliminate infection, with a particular focus on eliminating the persistence of viral cccDNA in the nuclei of hepatocytes. In the context of chronic hepatitis B, new definitions of 'cure' are emerging, such as 'functional' and 'virological' cure, defined by stable off-therapy suppression of viremia and antigenemia, and the normalization of serum ALT and other liver-related laboratory tests. Continued advances in the understanding of the complex biology of chronic hepatitis B have resulted in the development of new, experimental therapies targeting viral and host factors and pathways previously not accessible to therapy, approaches which may lead to virological cures in the near term and functional cures upon long term follow-up. This article forms part of a symposium in Antiviral Research on "An unfinished story: from the discovery of the Australia antigen to the development of new curative therapies for hepatitis B."

Hepatitis B virus replication and sex-determining region Y box 4 production are tightly controlled by a novel positive feedback mechanism

Hepatitis B virus (HBV) infection is a major cause of liver diseases. However, the mechanisms underlying HBV infection and pathogenesis remain largely unknown. The sex-determining region Y box 4 (Sox4) is a transcriptional factor, which preferentially regulates the development of various organs, tissues, and cancers. But, the role of Sox4 in viral infection and pathogenesis has not been elucidated. Here, we demonstrated that Sox4 is up-regulated by HBV, and revealed the mechanism by which HBV regulates Sox4 expression. First, HBV stimulates Sox4 expression through transcriptional factor Yin Yang 1 (YY1), which binds to Sox4 promoter to activate Sox4 transcriptional activity. Second, miR-335, miR-129-2 and miR-203 inhibit Sox4 expression by targeting its mRNA 3’UTR, while HBV suppresses the microRNAs expression, resulting in up-regulating Sox4 post-transcriptionally. Third, Sox4 protein is degraded by proteasome, while HBV surface protein (HBsAg) prevents Sox4 from degradation by directly interacting with the protein, thereby enhancing Sox4 production post-translationlly. More interestingly, HBV-activated Sox4 in turn facilitates HBV replication by direct binding to the viral genome via its HMG box. Thus, this study revealed a novel positive feedback mechanism by which Sox4 production and HBV replication are tightly correlated.

The direct and indirect roles of HBV in liver cancer: prospective markers for HCC screening and potential therapeutic targets

Chronic hepatitis B virus (HBV) infection remains the number one risk factor for hepatocellular carcinoma (HCC), accounting for more than 600 000 deaths/year. Despite highly effective antiviral treatment options, chronic hepatitis B (CHB), subsequent end-stage liver disease and HCC development remain a major challenge worldwide. In CHB, liver damage is mainly caused by the influx of immune cells and destruction of infected hepatocytes, causing necro-inflammation. Treatment with nucleoside/nucleotide analogues can effectively suppress HBV replication in patients with CHB and thus decrease the risk for HCC development. Nevertheless, the risk of HCC in treated patients showing sufficient suppression of HBV DNA replication is significantly higher than in patients with inactive CHB, regardless of the presence of baseline liver cirrhosis, suggesting direct, long-lasting, predisposing effects of HBV. Direct oncogenic effects of HBV include integration in the host genome, leading to deletions, cis/trans-activation, translocations, the production of fusion transcripts and generalized genomic instability, as well as pleiotropic effects of viral transcripts (HBsAg and HBx). Analysis of these viral factors in active surveillance may allow early identification of high-risk patients, and their integration into a molecular classification of HCC subtypes might help in the development of novel therapeutic approaches.

Spontaneous HBsAg loss in Korean patients: relevance of viral genotypes, S gene mutations, and covalently closed circular DNA copy numbers

Background/Aims

Occult HBV infection can persist following HBsAg loss and be transmitted, but the virological features are not well defined.

Methods

Here we investigated 25 Korean patients who lost HBsAg during follow up, either spontaneously or subsequent to therapy.

Results

Whereas subtype adr (genotype C) was found in 96% of HBsAg positive patients, 75 % of patients who lost HBsAg spontaneously were seemed to be infected with the ayw subtype with sequence similar to genotype D. Mutations in the major hydrophilic region (MHR) of HBsAg were found in 7 patients who lost HBsAg spontaneously. The mutations include T123S, M125I/N, C139R, D144E, V177A, L192F, and W196L, some of which have not been reported before. Functional analysis via transfection experiments indicate that the C139R and D144E mutations drastically reduced HBsAg antigenicity, while the Y225del mutation found in one interferon-treated patient impaired HBsAg secretion.

Conclusions

Lack of detectable HBsAg in patient serum could be explained by low level of ccc DNA in liver tissue, low antigenicity of the surface protein, or its secretion defect.