An Increase in the Levels of Middle Surface Antigen Characterizes Patients Developing HBV-Driven Liver Cancer Despite Prolonged Virological Suppression

Hepatitis B surface antigen glycan isomer is a predictor of the development of hepatocellular carcinoma during nucleoside/nucleotide analog therapy

AIM

A recombinant monoclonal antibody against the hepatitis B surface antigen glycan isomer (HBsAgGi) was newly developed using the O-glycosylated PreS2 peptide in M-HBsAg of hepatitis B virus (HBV) genotype C. However, the association between HBsAgGi and the development of hepatocellular carcinoma (HCC) during nucleoside/nucleotide analog (NA) therapy remains unknown.

METHODS

A total of 112 HBV genotype C-infected patients who were treated with NA were included in this study. We assessed the association between HBV markers, including HBsAgGi and other conventional markers, and the development of HCC during NA therapy.

RESULTS

Ten patients developed HCC during the follow-up period. Of the HBV markers, HBsAg (≤3.53 log IU/mL; p = 0.047), HBsAgGi/HBsAg ratio (≥1.10; p = 0.035), and HBV DNA (≤6.3 log copies/mL; p = 0.012) at baseline and HBsAg (≤3.19 log IU/mL; p = 0.033) and HBsAgGi/HBsAg ratio (≥1.09; p = 0.003) at 48 weeks after NA therapy were significantly associated with the development of HCC according to the log rank test. In contrast, no significant association was observed between HBsAgGi and the development of HCC. Multivariate analysis revealed that a platelet count at baseline ≤88 × 103/mm3 (p = 0.026; hazard ratio [HR], 10.577) and an HBsAgGi/HBsAg ratio at 48 weeks after NA therapy ≥1.09 (p = 0.040; HR, 10.099) were independently and significantly associated with the development of HCC.

CONCLUSIONS

Our findings suggest that a combination of on-treatment HBsAgGi and HBsAg predicts the development of HCC during NA therapy.

Hepatitis B Surface Antigen Isoforms: Their Clinical Implications, Utilisation in Diagnosis, Prevention and New Antiviral Strategies

The hepatitis B surface antigen (HBsAg) is a multifunctional glycoprotein composed of large (LHB), middle (MHB), and small (SHB) subunits. HBsAg isoforms have numerous biological functions during HBV infection-from initial and specific viral attachment to the hepatocytes to initiating chronic infection with their immunomodulatory properties. The genetic variability of HBsAg isoforms may play a role in several HBV-related liver phases and clinical manifestations, from occult hepatitis and viral reactivation upon immunosuppression to fulminant hepatitis and hepatocellular carcinoma (HCC). Their immunogenic properties make them a major target for developing HBV vaccines, and in recent years they have been recognised as valuable targets for new therapeutic approaches. Initial research has already shown promising results in utilising HBsAg isoforms instead of quantitative HBsAg for correctly evaluating chronic infection phases and predicting functional cures. The ratio between surface components was shown to indicate specific outcomes of HBV and HDV infections. Thus, besides traditional HBsAg detection and quantitation, HBsAg isoform quantitation can become a useful non-invasive biomarker for assessing chronically infected patients. This review summarises the current knowledge of HBsAg isoforms, their potential usefulness and aspects deserving further research.

HBsAg protein composition and clinical outcomes in chronic hepatitis D and variations across HBeAg-negative chronic HBsAg carriers

Background & Aims

HBsAg proteins are useful to identify HBV inactive carriers (ICs), but data on chronic hepatitis D (CHD) are scarce. This study aimed to describe HBsAg composition in CHD, its changes during the evolution, and the potential association with clinical outcomes. In addition, we assess the composition of HBsAg across different HBV genotypes and validate previous results on HBsAg proteins in an independent HBV cohort.

Methods

Quantitative HBsAg, medium HBsAg proteins (MHBs), and large HBsAg proteins (LHBs) were measured in two cohorts. The first cohort consisted of patients with CHD. A cross-sectional study of samples from two European institutions (N = 46) was conducted. Outcomes were assessed in a retrospective-prospective study of those patients with a follow-up of >1 year (n = 36), and the longitudinal evolution of HBsAg proteins in those with samples >5 years apart (n = 12) was analysed. The second cohort consisted of patients with HBeAg-negative HBV, and a cross-sectional study was performed (N = 141).

Results

Forty-one (89%) patients with CHD had detectable HDV-RNA, and the presence of HDV-RNA was associated with higher LHBs proportion (p = 0.010). Baseline MHBs (p = 0.051) and MHBs proportion (p = 0.086) tended to be higher in those developing clinical outcomes (9/36, 25%) after a median follow-up of 5.9 years. Patients in which HDV-RNA became spontaneously undetectable during follow-up (5/31, 16.1%) tended to present lower MHBs proportion (p = 0.085). In the longitudinal study, changes in LHBs proportion were observed (p = 0.041), whereas MHBs proportion remained stable (p = 0.209). Regarding HBV, ICs showed lower LHBs proportion (p = 0.027). LHBs and MHBs differed significantly according to HBV genotype, regardless of the HBV phase.

Conclusions

Patients with CHD with detectable HDV-RNA presented higher LHBs proportion than those with undetectable HDV-RNA. A trend toward having higher baseline MHBs proportion was observed in patients who developed clinical outcomes or remained with detectable HDV-RNA. This study validates the different HBsAg composition in HBV ICs and reveals the HBV-genotype influence in HBsAg composition.

Impact and implications

The composition of HBsAg in chronic hepatitis D differs in patients with detectable and undetectable HDV viral load and may help predict the likelihood of achieving undetectable HDV viraemia and the development of clinical events such as decompensation. The composition of the surface antigen is also useful to distinguish inactive carriers of HBV, and it varies according to HBV genotype.

Kinetics of serum O-glycosylated M-hepatitis B surface antigen with hepatocellular carcinoma history and nucleos(t)ide analogue therapy in hepatitis B patients

A newly developed O-glycosylated M-hepatitis B surface antigen (HBsAgGi) measurement system can detect hepatitis B surface antigen (HBsAg) associated with infectious particles. We investigated the association of HBsAgGi levels with clinical parameters and a history of hepatocellular carcinoma (HCC) development in a cross-sectional cohort analysis (Study 1) as well as the quantitative changes in HBsAgGi during nucleos(t)ide analogue (NA) therapy in a longitudinal cohort analysis (Study 2). A total of 124 patients with genotype C chronic HBV infection were analysed in Study 1 to evaluate correlations of HBsAgGi with conventional HBV markers and HCC history. Among those, 36 patients receiving NA therapy were enrolled in Study 2 for quantitative comparisons between pre-treatment baseline and 48 weeks of NA therapy. In Study 1, serum HBsAgGi was significantly associated with HBsAg (r = .5857, p < .00001) and weakly but significantly correlated with HBV DNA (r = .2936, p = .001). Although HBsAgGi (p = .111) was comparable between HCC history (+) group and HCC history (-) group, the HBsAgGi/HBsAg ratio (p = .011) was significantly higher in HCC history (+) patients. In Study 2, HBsAgGi was significantly decreased after 48 weeks of NA therapy (p < .001). HBsAg findings were similar (p = .005) along with an HBV DNA reduction (p < .001). In the baseline hepatitis B e antigen (HBeAg) (+) subgroup, HBsAgGi decreased significantly between baseline and 48 weeks of NA (p = .005), while HBsAg was comparable (p = .051). Low HBsAg and high HBsAgGi were associated with a history of HCC development. HBsAgGi decreased significantly by 48-week NA therapy.

Big Data Analysis and Application of Liver Cancer Gene Sequence Based on Second-Generation Sequencing Technology

In big data analysis with the rapid improvement of computer storage capacity and the rapid development of complex algorithms, the exponential growth of massive data has also made science and technology progress with each passing day. Based on omics data such as mRNA data, microRNA data, or DNA methylation data, this study uses traditional clustering methods such as kmeans, K-nearest neighbors, hierarchical clustering, affinity propagation, and nonnegative matrix decomposition to classify samples into categories, obtained: (1) The assumption that the attributes are independent of each other reduces the classification effect of the algorithm to a certain extent. According to the idea of multilevel grid, there is a one-to-one mapping from high-dimensional space to one-dimensional. The complexity is greatly simplified by encoding the one-dimensional grid of the hierarchical grid. The logic of the algorithm is relatively simple, and it also has a very stable classification efficiency. (2) Convert the two-dimensional representation of the data into the one-dimensional representation of the binary, realize the dimensionality reduction processing of the data, and improve the organization and storage efficiency of the data. The grid coding expresses the spatial position of the data, maintains the original organization method of the data, and does not make the abstract expression of the data object. (3) The data processing of nondiscrete and missing values provides a new opportunity for the identification of protein targets of small molecule therapy and obtains a better classification effect. (4) The comparison of the three models shows that Naive Bayes is the optimal model. Each iteration is composed of alternately expected steps and maximal steps and then identified and quantified by MS.

Pathogenicity and virulence of Hepatitis B virus

Hepatitis B virus (HBV) is a hepatotropic virus and an important human pathogen. There are an estimated 296 million people in the world that are chronically infected by this virus, and many of them will develop severe liver diseases including hepatitis, cirrhosis and hepatocellular carcinoma (HCC). HBV is a small DNA virus that replicates via the reverse transcription pathway. In this review, we summarize the molecular pathways that govern the replication of HBV and its interactions with host cells. We also discuss viral and non-viral factors that are associated with HBV-induced carcinogenesis and pathogenesis, as well as the role of host immune responses in HBV persistence and liver pathogenesis.