Distinct distribution pattern of hepatitis B virus genotype C and D in liver tissue and serum of dual genotype infected liver cirrhosis and hepatocellular carcinoma patients

Hepatitis B virus genotypes in precision medicine of hepatitis B-related hepatocellular carcinoma: Where we are now

Hepatitis B virus (HBV) infection is a major player in chronic hepatitis B that may lead to the development of hepatocellular carcinoma (HCC). HBV genetics are diverse where it is classified into at least 9 genotypes (A to I) and 1 putative genotype (J), each with specific geographical distribution and possible different clinical outcomes in the patient. This diversity may be associated with the precision medicine for HBV-related HCC and the success of therapeutical approaches against HCC, related to different pathogenicity of the virus and host response. This Editorial discusses recent updates on whether the classification of HBV genetic diversity is still valid in terms of viral oncogenicity to the HCC and its precision medicine, in addition to the recent advances in cellular and molecular biology technologies.

Advanced MR Imaging of the Pancreas

MR imaging can be optimized to evaluate a spectrum of pancreatic disorders with advanced sequences aimed to provide quantitative results and increase MR diagnostic capabilities. The pancreas remains a challenging organ to image because of its small size and location deep within the body. Besides its anatomic limitations, pancreatic pathology can be difficult to identify in the early stages. For example, subtle changes in ductal anatomy and parenchymal composition seen in early chronic pancreatitis are imperceptible with other modalities, such as computed tomography. This article reviews the application of MR imaging techniques and emerging MR sequences used in pancreas imaging.

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.

Oncogenic potential of hepatitis B virus subgenotype D1 surpasses D3: significance in the development of hepatocellular carcinoma

Despite widespread distribution of hepatitis B virus (HBV)-genotype D, the clinical implications of its ten subgenotypes (D1-D10) have not been well documented. Here, we have investigated the impact of two major circulating HBV/D subgenotypes, D1 and D3 in Eastern India towards pathogenesis of liver disease progression to hepatocellular carcinoma (HCC). HBV subgenotypes were determined using full-length genome sequences of HBV isolates from patients with chronic hepatitis B (CHB), liver cirrhosis (LC) and HCC. Impact of D1 and D3 on viral lifecycle and disease progression was assessed by several in vitro assays. Phylogenetic tree analysis revealed that HBV/D1 and HBV/D3 were the two predominating HBV subgenotypes circulating in Eastern India. Interestingly, the frequency of patients infected with HBV/D1 was noticed progressively rising from CHB to HCC through LC while the increasing frequency of HBV/D3 declined suddenly in HCC implicating HBV/D1 might have greater oncogenic potential than HBV/D3. Similar to higher viral load noted in HCC patients infected with HBV/D1 than HBV/D3, the larger amount of intracellular/extracellular viral DNA and secreted HBsAg levels in transfected cell lines also implicated that HBV/D1 might replicate faster than HBV/D3. Again, higher expression of marker genes related to endoplasmic reticulum stress, epithelial-mesenchymal transition, DNA double strand breaks, angiogenesis etc. and faster rate of cellular migration and anchorage independent growth cumulatively suggested that compared to HBV/D3, HBV/D1 generates more liver injuries which eventually culminates into HCC. Therefore, our results highlight the importance of determination of subgenotypes of HBV in CHB patients, so that high-risk individual can be monitor periodically that may help to detect HCC at early stages.

Current Scenario of Hepatitis B and Its Treatment in India

Hepatitis B is a significant public health problem in India, yet disease awareness is very low among the general population. The disease is mostly acquired horizontally, but the role of vertical transmission should not be underestimated. In spite of the fact that the majority of cases are e negative disease, most patients present in the advanced stage and even with hepatocellular carcinoma, the leading cause of which is hepatitis B. High-risk groups (especially tribals) also harbour significant disease burden and have a high prevalence of occult infection, supporting the potential of unknowingly spreading the disease. Findings on the relation of genotypes with disease severity or drug action have been conflicting. Though recently, oral antivirals with high genetic barrier to resistance have shown good viral suppression in the long term, e and s seroconversion is poor and relapse is universal upon therapy discontinuation. As no cure is possible with the currently available therapy, the target is long-term viral suppression by prolonged administration of oral antivirals; unfortunately, this leads to poor treatment adherence, which along with the high cost of therapy results in disease progression and spread of infection. At present, therefore, emphasis should be put on health education of the general and high-risk populations, along with health care workers to increase knowledge on such preventive measures as avoiding unsafe injection practices, high-risk sex, performing unnecessary injection and blood transfusion and providing proper screening of blood products; these efforts should be combined with intensive screening and aggressive vaccination programs, especially in high-risk groups and areas of high endemicity. Vaccination strategies are still below par and logistics should be developed for wider coverage; in addition, further research should be carried out on the efficacy and mode of usage for different types of vaccine.

Synergistic impact of mutations in Hepatitis B Virus genome contribute to its occult phenotype in chronic Hepatitis C Virus carriers

We characterized occult HBV (OHBV) from hepatitis B surface antigen (HBsAg)-negative chronic HCV carriers of Eastern India to explore the impact of genomic variability of HBV in causing undetectability of HBsAg and low viremia that define the occult phenomenon. Screening of sera samples revealed the presence of OHBV in 17.8% of HCV-infected patients. Determination of full-length OHBV sequences and comparison with that from HBsAg-positive carriers led to the detection of distinct substitutions/mutations in PreS2, S, P and X ORFs and in X-promoter and Enhancer-II of OHBV. These mutations were introduced in wild-type HBV and their effects were evaluated by transfection in Huh7 cells. In vitro assays demonstrated that S-substitutions resulted in antigenically modified HBsAg that escaped detection by immunoassays whereas those in ORF-P caused significant decline in viral replication. Impairment in Enhancer-II and X-promoter activities were noted due to occult-associated mutations that generated reduced pregenomic RNA and intracellular HBV-DNA. Additionally, Enhancer-II mutations altered the small to large surface protein ratio and diminished extracellular HBV-DNA and HBsAg secretion. Further, mutations in PreS2, X and enhancer-II increased Grp78-promoter activity, suggesting that OHBV could trigger endoplasmic reticulum stress. Thus viral mutations contribute synergistically towards the genesis of occult phenotype and disease progression.

Occult endocrine dysfunction in patients with cirrhosis of liver

BACKGROUND

Liver dysfunction leads to endocrine disturbance due to the alteration in protein metabolism or synthesis. We studied the presence of occult endocrine dysfunction in liver cirrhosis and compared the same with underlying etiology.

MATERIALS AND METHODS

We evaluated thirty patients with liver cirrhosis in this cross-sectional, observational study. All subjects were assessed for pituitary, thyroid, adrenal, and gonadal function. The patients were divided into Group 1 (cirrhosis, n = 30) and Group 2 (controls, n = 15) and the data were analyzed with appropriate statistical tests.

RESULTS

The study participants (20 males, 10 females) had a mean age of 54.5 ± 12.4 years and duration of the cirrhosis 5.1 ± 2.7 years. Four patients were in Child Class A, 11 and 15 patients were in Child Classes B and C, respectively. Eleven out of thirty patients (37%) had endocrine disorders, that include subclinical hypothyroidism (n = 3), primary hypothyroidism (n = 1), Sick Euthyroid syndrome (n = 3), central hypothyroidism (n = 2), secondary hypogonadism (n = 3) and growth hormone deficiency in three patients. Two patients had partial hypopituitarism and one patient had complete hypopituitarism.

CONCLUSION

Occult endocrine dysfunction of thyroid and gonadal axes is common in patients with cirrhosis of the liver. The hormonal abnormalities are not different based on the etiology of the cirrhosis.

Hepatitis B and Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer death worldwide, and its incidence has been increasing in the last decade largely in parallel to the incidence and duration of exposure to hepatitis B and C. The widespread implementation of hepatitis B vaccine, hepatitis B antivirals, and the introduction of direct antiviral therapies for hepatitis C virus may have a substantial impact in reducing the incidence of HCC. This report reviews the risk factors and underlying mechanisms associated with the development of HCC in hepatitis B, along with advances in the diagnosis, imaging, and management of HCC.

Hepatitis B virus genotypes: epidemiological and clinical relevance in Asia

Hepatitis B virus (HBV) is characterized by a high genetic heterogeneity since it replicates via a reverse transcriptase that lacks proofreading ability. Up to now, ten genotypes (A-J) have been described, with genotype A and D being ubiquitous but most prevalent in Europe and Africa, genotype B and C being confined to Asia and Oceania. Infections with other genotypes such as E, F, G and H are also occasionally observed in Asia. Genotype I is rare and can be found in Laos, Vietnam, India and China, whereas genotype J has been described in Japan and Ryukyu. Novel variants generated by recombination and co-infection with other genotypes have gradually gotten worldwide attention and may be correlated with certain clinical features. There are substantial differences in HBV infection regarding prevalence, clinical manifestation, disease progression and response to antiviral therapy. Due to the complex interplay among viral, host and environmental factors, the relationship between HBV genotypes and clinical profiles remains incompletely revealed. In general, genotype A is associated with better response to interferon therapy; genotype C, and to lesser extent B, usually represent a risk factor for perinatal infection and are associated with advanced liver diseases such as cirrhosis and hepatocellular carcinoma; genotype D may be linked with poor response to interferon therapy. Future studies with better design and larger sample size are warranted to further clarify the controversial issues and guide the day-to-day clinical practice.

Significance of hepatitis virus infection in the oncogenic initiation of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common causes of cancer-related death worldwide. Chronic infection of hepatitis B virus (HBV) and/or hepatitis C virus (HCV) is a major risk factor in the development of the HCC, independently from excessive alcohol abuse and metabolic disease. Since the biology of HBV and HCV is different, their oncogenic effect may go through different mechanisms, direct and/or indirect. Viral hepatitis infection is associated with cellular inflammation, oxidative stress, and DNA damage, that may lead to subsequent hepatic injuries such as chronic hepatitis, fibrosis, cirrhosis, and finally HCC. Direct oncogenic properties of these viruses are related with their genotypic characteristics and the ability of viral proteins to interact with host proteins, thus altering the molecular pathways balance of the cells. In addition, the integration of HBV DNA, especially the gene S and X, in a particular site of the host genome can disrupt chromosomal stability and may activate various oncogenic mechanisms, including those in hematopoietic cells. Recently, several studies also had demonstrated that viral hepatitis could trigger the population of hepatic cancer stem cells. This review summarize available pre-clinical and clinical data in literature regarding oncogenic properties of HBV and HCV in the early initiation of HCC.

Occult endocrine dysfunction in patients with cirrhosis of liver

BACKGROUND

Liver dysfunction leads to endocrine disturbance due to the alteration in protein metabolism or synthesis. We studied the presence of occult endocrine dysfunction in liver cirrhosis and compared the same with underlying etiology.

MATERIALS AND METHODS

We evaluated thirty patients with liver cirrhosis in this cross-sectional, observational study. All subjects were assessed for pituitary, thyroid, adrenal, and gonadal function. The patients were divided into Group 1 (cirrhosis, n = 30) and Group 2 (controls, n = 15) and the data were analyzed with appropriate statistical tests.

RESULTS

The study participants (20 males, 10 females) had a mean age of 54.5 ± 12.4 years and duration of the cirrhosis 5.1 ± 2.7 years. Four patients were in Child Class A, 11 and 15 patients were in Child Classes B and C, respectively. Eleven out of thirty patients (37%) had endocrine disorders, that include subclinical hypothyroidism (n = 3), primary hypothyroidism (n = 1), Sick Euthyroid syndrome (n = 3), central hypothyroidism (n = 2), secondary hypogonadism (n = 3) and growth hormone deficiency in three patients. Two patients had partial hypopituitarism and one patient had complete hypopituitarism.

CONCLUSION

Occult endocrine dysfunction of thyroid and gonadal axes is common in patients with cirrhosis of the liver. The hormonal abnormalities are not different based on the etiology of the cirrhosis.