Quantification of hepatitis B virus covalently closed circular DNA in patients with hepatocellular carcinoma

Tenofovir vs Entecavir on the Prognosis of Patients With Hepatitis B Virus-Related Hepatocellular Carcinoma After Liver Resection: The Role of HBsAg Levels

INTRODUCTION

Our study aimed to explore whether hepatitis B surface antigen (HBsAg) levels affected the role of nucleot(s)ide analog treatment (entecavir [ETV] and tenofovir disoproxil fumarate [TDF]) in improving the prognosis of patients with hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) after liver resection.

METHODS

A total of 865 patients with HBV-related HCC after hepatectomy treated with TDF or ETV were included in our study. Patients were divided into the high HBsAg cohort (n = 681) and the low HBsAg cohort (n = 184). Propensity score matching (PSM) analysis was used to reduce the impact of potential confounding factors. Kaplan-Meier method and competing risk analysis were used to compare the survival outcomes.

RESULTS

In the high HBsAg cohort, patients in the TDF group had better recurrence-free survival (RFS) and overall survival (OS) compared with patients in the ETV group both before (RFS: P < 0.001; OS: P < 0.001) and after (RFS: P = 0.005; OS: P = 0.035) PSM. TDF treatment was a favorable factor independently associated with RFS (hazard ratio: 0.58, 95% confidence interval: 0.45-0.75, P < 0.001) and OS (hazard ratio: 0.43, 95% confidence interval: 0.28-0.66, P < 0.001). In the low HBsAg cohort, no difference was observed in RFS and OS between the TDF group and the ETV group both before (RFS: P = 0.140; OS: P = 0.640) and after (RFS: P = 0.480; OS: P = 0.920) PSM. TDF treatment remained superiority after controlling for competing events by competing risk analysis in the high HBsAg cohort.

DISCUSSION

TDF treatment was superior to ETV treatment in improving RFS and OS of HBV-related HCC patients with high HBsAg level after liver resection. Even after controlling for survival competing events, the advantage of TDF treatment remained. Our findings may better help clinicians to assign individualized antiviral regimens to patients with HBV-related HCC after liver resection.

Development and validation of a multivariable nomogram predictive of hepatitis B e antigen seroconversion after pregnancy in hepatitis B virus-infected mothers

Background and aims

Current guidelines are controversial regarding the continuation of nucleos(t)ide analogues (NAs) therapy after delivery in Hepatitis B virus (HBV)-infected pregnant women. The postpartum period may be an opportune moment for achieving hepatitis B e antigen (HBeAg) seroconversion earlier with constant NAs therapy due to the restoration of immune function after delivery. We investigated prenatal and pregnant factors associated with HBeAg seroconversion after pregnancy and developed a nomogram to predict HBeAg seroconversion rates, aiding decision-making for optimal management in women.

Methods

We retrospectively included 489 HBeAg-positive mothers as the training cohort from January 2014 to December 2018 and prospectively enrolled 94 patients as the external validation cohort from January 2019 to December 2021 at the First Affiliated Hospital of Xi'an Jiaotong University. In the training cohort, independent predictors were identified using the least absolute shrinkage and selection operator (LASSO) regression algorithm. Subsequently, multivariate logistic regression was employed to establish the nomogram. Model performance was assessed using the area under the receiver operating characteristic curve (AUC), calibration plots, and decision curve analysis (DCA). Both discrimination and calibration were evaluated through bootstrapping with 1,000 resamples. The external validation cohort was subsequently used to validate the nomogram.

Results

Factors such as pregnancy hepatitis flare (OR: 5.122, 95% CI: 2.725-9.928, p < 0.001), NAs therapy after delivery (OR: 15.051, 95% CI: 6.954-37.895, p: <0.001), hepatitis B surface antigen (HBsAg) (OR: 0.549, 95% CI: 0.366-0.812, p: 0.003) and HBV DNA level at delivery (OR: 0.785, 95% CI: 0.619-0.986, p: 0.041) were included in the final risk model. The AUC in the training set was 0.873 (95% CI: 0.839-0.904). The calibration curve of the nomogram closely resembled the ideal diagonal line. DCA showed a significantly better net benefit in the model. External validation also confirmed the reliability of the prediction nomogram. The AUC in the external validation set was 0.889 (95% CI: 0.801-0.953). The calibration curve for the external validation set was in close proximity to the ideal diagonal line. DCA also demonstrated a significant net benefit associated with the predictive model, consistent with the findings in the training set. Finally, the nomogram has been translated into an online risk calculator that is freely available to the public (https://wendyzhong.shinyapps.io/DynNomapp/).

Conclusion

We developed a nomogram based on prenatal and pregnant factors to estimate HBeAg seroconversion after delivery in women. This tool provides clinicians with a precise and effective way to identify individuals likely to undergo HBeAg seroconversion postpartum, aiding in decision-making for optimal management.

cccDNA-Targeted Drug Screen Reveals a Class of Antihistamines as Suppressors of HBV Genome Levels

Chronic infection with hepatitis B virus (HBV) is incurable, as the current therapeutics cannot eliminate its persistent genomic material, cccDNA. Screening systems for cccDNA-targeting therapeutics are unavailable, as low copies of cccDNA in vitro complicate detection. To address this, cccDNA copies were massively increased to levels detectable via automated plate readers. This was achieved via continuous infection in a contact-free co-culture of an HBV generator (clone F881), which stably produced clinically relevant amounts of HBV, and HBV acceptors selected to carry high cccDNA loads. cccDNA-targeted therapeutics were then identified via reduced cccDNA-specific fluorescence, taking differences in the cell numbers and viability into account. Amongst the drugs tested, the H1 antihistamine Bilastine, HBVCP inhibitors and, surprisingly, current HBV therapeutics downregulated the cccDNA significantly, reflecting the assay's accuracy and sensitivity in identifying drugs that induce subtle changes in cccDNA levels, which take years to manifest in vivo. Bilastine was the only therapeutic that did not reduce HBV production from F881, indicating it to be a novel direct suppressor of cccDNA levels. When further assessed, only the structurally similar antihistamines Pitolisant and Nizatidine suppressed cccDNA levels when other H1 antihistamines could not. Taken together, our rapid fluorescence cccDNA-targeted drug screen successfully identified a class of molecules with the potential to treat hepatitis B.

Development and application of hepatocellular carcinoma risk prediction model based on clinical characteristics and liver related indexes

BACKGROUND

Hepatocellular carcinoma (HCC) is difficult to diagnose with poor therapeutic effect, high recurrence rate and has a low survival rate. The survival of patients with HCC is closely related to the stage of diagnosis. At present, no specific serological indicator or method to predict HCC, early diagnosis of HCC remains a challenge, especially in China, where the situation is more severe.

AIM

To identify risk factors associated with HCC and establish a risk prediction model based on clinical characteristics and liver-related indicators.

METHODS

The clinical data of patients in the Affiliated Hospital of North Sichuan Medical College from 2016 to 2020 were collected, using a retrospective study method. The results of needle biopsy or surgical pathology were used as the grouping criteria for the experimental group and the control group in this study. Based on the time of admission, the cases were divided into training cohort (n = 1739) and validation cohort (n = 467). Using HCC as a dependent variable, the research indicators were incorporated into logistic univariate and multivariate analysis. An HCC risk prediction model, which was called NSMC-HCC model, was then established in training cohort and verified in validation cohort.

RESULTS

Logistic univariate analysis showed that, gender, age, alpha-fetoprotein, and protein induced by vitamin K absence or antagonist-II, gamma-glutamyl transferase, aspartate aminotransferase and hepatitis B surface antigen were risk factors for HCC, alanine aminotransferase, total bilirubin and total bile acid were protective factors for HCC. When the cut-off value of the NSMC-HCC model joint prediction was 0.22, the area under receiver operating characteristic curve (AUC) of NSMC-HCC model in HCC diagnosis was 0.960, with sensitivity 94.40% and specificity 95.35% in training cohort, and AUC was 0.966, with sensitivity 90.00% and specificity 94.20% in validation cohort. In early-stage HCC diagnosis, the AUC of NSMC-HCC model was 0.946, with sensitivity 85.93% and specificity 93.62% in training cohort, and AUC was 0.947, with sensitivity 89.10% and specificity 98.49% in validation cohort.

CONCLUSION

The newly NSMC-HCC model was an effective risk prediction model in HCC and early-stage HCC diagnosis.

circGFRA1: A circular RNA with important roles in human carcinogenesis

Circular RNAs (circRNAs) are a type of covalently closed RNA molecules, which are mainly formed by back splicing of a precursor mRNA upstream exon into a downstream exon. Abnormally expressed circRNAs can modulate gene transcription by indirectly interacting with microRNAs (miRNAs). According to the current studies, circGFRA1 has been suggested to be upregulated in various cancers. circGFRA1 (hsa_circ_005239) is a type of cancer-related circRNA, which is predicted to be originated from the GFRA1 on chromosome 10. circGFRA1 can act as a sponge for several miRNAs, including miR-34a, miR-1228, miR-361-5p, miR-149, miR-498, miR-188-3p, miR-3064-5p, miR-449a. Additionally, it can regulate signaling pathways such as TGF-β and PI3K/ AKT. circGFRA1 upregulation has been correlated with patients' poor overall survival in diverse cancers. In the present review, we have summarized the oncogenic effect of circGFRA1 in various cancers according to the adopted criteria from in vitro, in vivo, and clinical research. Moreover, functional enrichment analysis was performed on the circGFRA1 host gene and its protein interaction network to detect gene ontology and related pathways.

Role of hepatitis B virus in development of hepatocellular carcinoma: Focus on covalently closed circular DNA

Chronic infection with hepatitis B virus (HBV) remains a major global health problem, especially in developing countries. It may lead to prolonged liver damage, fibrosis, cirrhosis, and hepatocellular carcinoma. Persistent chronic HBV infection is related to host immune response and the stability of the covalently closed circular DNA (cccDNA) in human hepatocytes. In addition to being essential for viral transcription and replication, cccDNA is also suspected to play a role in persistent HBV infections or hepatitis relapses since cccDNA is very stable in non-dividing human hepatocytes. Understanding the pathogenicity and oncogenicity of HBV components would be essential in the development of new diagnostic tools and treatment strategies. This review summarizes the role and molecular mechanisms of HBV cccDNA in hepatocyte transformation and hepatocarcinogenesis and current efforts to its detection and targeting.

Circular RNAs regulate cancer-related signaling pathways and serve as potential diagnostic biomarkers for human cancers

Circular RNAs (circRNAs) are RNAs that have an important role in various pathological processes, including cancer. After the usage of high-throughput RNA sequencing, many circRNAs were found to be differentially expressed in various cancer cell lines and regulate cell signaling pathways by modulating particular gene expressions. Understanding their role in these pathways and what cancers they are found in can set the stage for identifying diagnostic and prognostic biomarkers and therapeutic targets of cancer. This paper will discuss which circRNAs are found in different cancers and what mechanisms they use to upregulate or downregulate certain cellular components.

Hepatitis B Virus Covalently Closed Circular DNA Predicts Postoperative Liver Cancer Metastasis Independent of Virological Suppression

New antiviral therapies against hepatitis B virus (HBV) focus on the elimination of covalently closed circular DNA (cccDNA). However, traditional cccDNA-specific quantitative PCR (qPCR) has a narrow effective range, hindering a reliable comparison between the levels of biopsy-derived cccDNAs. Collaterally, the prognostic role of cccDNA in HBV-related hepatocellular carcinoma (HCC) cannot be clearly defined. Here, we developed a peptide nucleic acid (PNA)-clamping qPCR method to provide a wider range of specific cccDNA quantification (up to 5 logs of effective range). Extrachromosomal DNA was extracted from para-neoplastic tissues for cccDNA quantification. In total, 350 HBV-related HCC patients were included for an outcome analysis. Without differential pre-dilution, cccDNA levels in para-neoplastic liver tissues were determined, ranging from < 2 × 10³ to 123.0 × 10⁶ copies/gram. The multivariate linear regression analysis showed that cccDNA was independently correlated with the HBV e antigen (p < 0.001) and serum HBV-DNA levels (p = 0.012). The Cox proportional hazard model analysis showed that cccDNA independently predicted overall survival (p = 0.003) and extrahepatic metastasis-free survival (p = 0.001). In virologically suppressed HCC patients, cccDNA still effectively predicted intrahepatic recurrence-free (p = 0.003) and extrahepatic metastasis-free (p = 0.009) survivals. In conclusion, cccDNA independently predicted postoperative extrahepatic metastasis-free survival.

Early and late recurrence of surgically resected hepatitis B virus-related hepatocellular carcinoma on nucleos(t)ide analogues therapy

BACKGROUND/PURPOSE

Hepatocellular carcinoma (HCC) is a highly recurrent tumor. Antiviral therapy with nucleos(t)ide analogues (NUCs) may reduce the risk of recurrence in hepatitis B virus (HBV)-related HCC. The risk factors associated with recurrence in HCC patients after surgical resection and with NUCs treatment should be delineated.

METHODS

Consecutive 339 HBV-related HCC patients receiving surgical resection of HCC with NUCs therapy (including 256 entecavir, 36 tenofovir, and 18 lamivudine) after the surgery were retrospectively reviewed. Factors related to the recurrence-free survival (RFS) and overall survival (OS) were evaluated.

RESULTS

After a median of 48.5 months of follow-up, 183 (54%) patients developed HCC recurrence, with the 5-year RFS of 42.8% and OS of 79%. Male gender (HR = 1.736, p = 0.037), baseline HBsAg level >200 IU/ml (HR = 1.748, p = 0.008), platelet count ≦100 (10⁹/L) (HR = 1.592, p = 0.023), presence of microscopic vascular invasion (MVI) (HR = 1.499, p = 0.026), safety cut margin of ≦0.5 cm (HR = 1.507, p = 0.013), and Ishak fibrosis score 5-6 (HR = 1.579, p = 0.009) were independent factors associated with RFS in multivariate analysis. While tumor burden, platelet count, MVI, and safety cut margin were factors associated with early recurrence; baseline HBsAg level, and platelet count were independent factors associated with late recurrence. Ishak fibrosis score 5-6, poor differentiation, MVI, diabetes mellitus were factors associated with OS in multivariate analysis.

CONCLUSION

For HBV-HCC patients on NUCs treatment, tumor factors are associated with early recurrence, while HBsAg level and thrombocytopenia determines late recurrence. For patient with a high baseline HBsAg level, warning of higher risk of recurrence is required even under NUCs treatment.

Early and Late Recurrence of Hepatitis B Virus-Associated Hepatocellular Carcinoma

BACKGROUND

Survival after liver resection of hepatocellular carcinoma (HCC) remains poor because of a high incidence of recurrence. We sought to investigate risk factors, patterns, and long-term prognosis among patients with early and late recurrence after liver resection for hepatitis B virus (HBV)-associated HCC.

METHODS

Data of consecutive patients undergoing curative resection for HBV-associated HCC were analyzed. According to the time to recurrence after surgery, recurrence was divided into early (≤2 years) and late recurrence (>2 years). Characteristics, patterns of initial recurrence, and postrecurrence survival (PRS) were compared between patients with early and late recurrence. Risk factors of early and late recurrence and predictors of PRS were identified by univariable and multivariable Cox regression analyses.

RESULTS

Among 894 patients, 322 (36.0%) and 282 (31.5%) developed early and late recurrence, respectively. On multivariable analyses, preoperative HBV-DNA >104 copies/mL was associated with both early and late recurrence, whereas postoperative no/irregular antiviral therapy was associated with late recurrence. Compared with patients with late recurrence, patients with early recurrence had a lower proportion of intrahepatic-only recurrence (72.0% vs. 91.1%, p < .001), as well as a lower chance of receiving potentially curative treatments for recurrence (33.9% vs. 50.7%, p < .001) and a worse median PRS (19.1 vs. 37.5 months, p < .001). Multivariable analysis demonstrated that early recurrence was independently associated with worse PRS (hazard ratio, 1.361; 95% confidence interval, 1.094-1.692; p = .006).

CONCLUSION

Although risk factors associated with early recurrence and late recurrence were different, a high preoperative HBV-DNA load was an independent hepatitis-related risk for both early and late recurrence. Early recurrence was associated with worse postrecurrence survival among patients with recurrence.

IMPLICATIONS FOR PRACTICE

Liver resection is the main curative treatment for hepatocellular carcinoma (HCC), but postoperative survival remains poor because of high recurrence rates. This study investigated the risk factors and patterns of early and late recurrence and found that a high preoperative hepatitis B virus (HBV) DNA load was an independent hepatitis-related risk factor for both. Early recurrence was also independently associated with worse postrecurrence survival. These data may provide insights into different biological origin and behavior of early versus late recurrence after resection for HBV-associated HCC, which could be helpful to make individualized treatment decision for recurrent HCC, as well as strategies for surveillance recurrence after resection.

Effect of HBV-HDV co-infection on HBV-HCC co-recurrence in patients undergoing living donor liver transplantation

PURPOSE

To evaluate the effect of hepatitis D virus (HDV) on hepatitis B virus-hepatocellular carcinoma (HBV-HCC) co-recurrence in patients undergoing living donor liver transplantation (LDLT) for HBV alone or HBV-HDV coinfection.

METHODS

Between 2002 and 2019, 254 HBV-HCC patients underwent LDLT. The patients were divided into two groups after the application of the exclusion criteria: HBV-HCC (Group B; n = 163) and HBV-HDV-HCC (Group D; n = 31). First, the B and D groups were compared in terms of demographic and clinical parameters. Second, patients with (n = 16) and without (n = 178) post-transplant HBV-HCC co-recurrences were grouped and compared in terms of the same parameters.

RESULTS

Although the risk of HBV-HCC co-recurrence in group D was 4.99-fold higher than in group B, the risk of HBV recurrence alone in group D was 12.5-fold lower than in group B. The AFP (OR = 4.4), Milan criteria (beyond; OR = 18.8), and HDV (OR = 8.1) were identified as the independent risk factors affecting post-transplant HBV-HCC co-recurrence. The Milan criteria (OR = 2.1) and HBV-HCC co-recurrence (OR = 10.9) were identified as the risk factors affecting post-transplant mortality. HBV-HCC co-recurrence developed in 26.5% of patients in Group B and 100% in Group D (OR = 40; p = 0.001). HCC recurrence alone developed in 10% of patients without HBV recurrence in group B and 0% of patients without HBV recurrence in group D (OR = 5.7).

CONCLUSION

This study showed that the risk of HBV recurrence alone was reduced by 12.5-fold in the presence of HDV; however, the HCC recurrence occurred in all patients with HDV when HBV recurrence developed.

Emerging Role of Circular RNAs in Cancer

Circular RNAs (circRNAs), which are generated mainly from back-splicing of exons in precursor mRNAs (pre-mRNAs), are a novel class of endogenous covalently closed RNA molecules. Their functions as microRNA sponges, protein scaffolds, and modulators of transcription and splicing, as well as occasional templates for polypeptide production, are beginning to be recognized, though the investigation of circRNAs is in its infancy. circRNAs play critical roles in diverse cellular processes. Aberrant expression of circRNAs in malignancies sustains cellular growth and proliferation, promotes cellular invasiveness, and circumvents cellular senescence and death, suggesting their potential for exploitation as clinical biomarkers and therapeutic targets. In this review, we highlight recent progress in research on circRNAs in cancer, emphasizing the molecular mechanisms and potential clinical value of circRNAs.

The mechanistic, diagnostic and therapeutic novel nucleic acids for hepatocellular carcinoma emerging in past score years

Despite The Central Dogma states the destiny of gene as 'DNA makes RNA and RNA makes protein', the nucleic acids not only store and transmit genetic information but also, surprisingly, join in intracellular vital movement as a regulator of gene expression. Bioinformatics has contributed to knowledge for a series of emerging novel nucleic acids molecules. For typical cases, microRNA (miRNA), long noncoding RNA (lncRNA) and circular RNA (circRNA) exert crucial role in regulating vital biological processes, especially in malignant diseases. Due to extraordinarily heterogeneity among all malignancies, hepatocellular carcinoma (HCC) has emerged enormous limitation in diagnosis and therapy. Mechanistic, diagnostic and therapeutic nucleic acids for HCC emerging in past score years have been systematically reviewed. Particularly, we have organized recent advances on nucleic acids of HCC into three facets: (i) summarizing diverse nucleic acids and their modification (miRNA, lncRNA, circRNA, circulating tumor DNA and DNA methylation) acting as potential biomarkers in HCC diagnosis; (ii) concluding different patterns of three key noncoding RNAs (miRNA, lncRNA and circRNA) in gene regulation and (iii) outlining the progress of these novel nucleic acids for HCC diagnosis and therapy in clinical trials, and discuss their possibility for clinical applications. All in all, this review takes a detailed look at the advances of novel nucleic acids from potential of biomarkers and elaboration of mechanism to early clinical application in past 20 years.

SOX2 Represses Hepatitis B Virus Replication by Binding to the Viral EnhII/Cp and Inhibiting the Promoter Activation

Hepatitis B virus (HBV) replication is controlled by four promoters (preS1, preS2, Cp, and Xp) and two enhancers (EnhI and EnhII). EnhII stimulates Cp activity to regulate the transcriptions of precore, core, polymerase, and pregenomic RNAs, and therefore, EnhII/Cp is essential for the regulation of HBV replication. This study revealed a distinct mechanism underlying the suppression of EnhII/Cp activation and HBV replication. On the one hand, the sex determining region Y box2 (SOX2), a transcription factor, is induced by HBV. On the other hand, SOX2, in turn, represses the expression levels of HBV RNAs, HBV core-associated DNA, hepatitis B surface antigen (HBsAg), and hepatitis B e antigen (HBeAg), thereby playing an inhibitory role during HBV replication. Further studies indicated that SOX2 bound to the EnhII/Cp DNA and repressed the promoter activation. With the deletion of the high mobility group (HMG) domain, SOX2 loses the ability to repress EnhII/Cp activation, viral RNA transcription, HBV core-associated DNA replication, HBsAg and HBeAg production, as well as fails to enter the nucleus, demonstrating that the HMG domain is required for the SOX2-mediated repression of HBV replication. Moreover, SOX2 represses HBsAg and HBeAg secretion in BALB/c mice sera, and attenuates HBV 3.5 kb RNA transcription and hepatitis B virus core protein (HBc) production in the liver tissues, demonstrating that SOX2 suppresses HBV replication in mice. Furthermore, the results revealed that the HMG domain was required for SOX2-mediated repression of HBV replication in the mice. Taken together, the above facts indicate that SOX2 acts as a new host restriction factor to repress HBV replication by binding to the viral EnhII/Cp and inhibiting the promoter activation through the HMG domain.

Dynamic prediction of liver cirrhosis risk in chronic hepatitis B patients using longitudinal clinical data

OBJECTIVES

In longitudinal studies, serum biomarkers are often measured longitudinally which is valuable to predict the risk of disease progression. Previous risk prediction models for liver cirrhosis restrict data to baseline or baseline and a single follow-up time point, which failed to incorporate the time-dependent marker information. The aim of this study is to develop risk model in patients with chronic hepatitis B for dynamic prediction of cirrhosis by incorporating longitudinal clinical data.

METHODS

Data from the hospital-based retrospective cohort at the Third Affiliated Hospital of Sun Yat-sen University, from 2004 to 2016, were analyzed. Using the multilevel logistic regression model, the time-dependent marker information and individual characteristics were taken as input, and the risk of at different time as the output.

RESULTS

At the end of follow-up, 8.8% of patients progressed to cirrhosis, the average estimate values of hepatitis B virus DNA and alanine aminotransferase demonstrated a downward trend, the aspartate aminotransferase/alanine aminotransferase ratio showed a flat trend overall. The important predictors were as follows: age, oral antiviral treatment, hepatitis B virus DNA. This risk prediction model had an area under the receiver operator characteristic curve of 0.835 (95% confidence interval: 0.772-0.899) and 0.809 (95% confidence interval: 0.708-0.910) in the derivation and validation sets, respectively.

CONCLUSION

Longitudinal prediction model can be used for dynamic prediction of disease progression and identify changing high-risk patients.

Hepatitis B Virus cccDNA in Hepatocellular Carcinoma Tissue Increases the Risk of Recurrence After Liver Transplantation

BACKGROUND

High hepatitis B virus (HBV) DNA level is strongly associated with hepatocellular carcinoma (HCC) development in chronic HBV infection. The aim of this study was to investigate the association between intrahepatic HBV DNA titer and post-liver transplantation (LT) prognosis for HBV-related HCC (HBV-HCC) patients.

METHODS

A total of 60 patients with HBV-HCC who underwent LT were retrospectively studied. Using quantitative TaqMan fluorescent real-time polymerase chain reaction assay, HBV total DNA (tDNA) and covalently closed circular DNA (cccDNA) were both quantified in tumor tissue (TT) and adjacent non-tumor tissue (ANTT) from the explanted liver.

RESULTS

The loads of tDNA and cccDNA in ANTT were associated with serum HBV DNA levels. Multivariate analysis showed that the presence of vascular invasion and cccDNA in TT were independent risk factors for tumor recurrence. The group of patients with cccDNA titers ≥31og_l0 copies/μg in TT had significantly higher cumulative recurrence rates than those with <31og_l0 copies/μg group. The cccDNA titers predicted the tumor recurrence with an area under the receiver operating characteristic curve of 0.664.

CONCLUSIONS

Our findings would assist the clinical implementation of a more personalized therapy for tumor recurrence control and improve the prognosis of HBV-HCC patients.

Hepatitis B and hepatocellular carcinoma recurrence after living donor liver transplantation: The role of the Milan criteria

BACKGROUND/AIMS

The aim of this study was to evaluate the effect of the Milan criteria on the hepatitis B virus (HBV) and hepatocellular carcinoma (HCC) recurrence in patients who underwent living donor liver transplantation due to HBV-induced cirrhosis and HCC.

MATERIALS AND METHODS

We evaluated a total of 142 patients, 88 who underwent transplantation due to HBV-induced cirrhosis and 54 due to HCC, between 2009 and 2014. In the posttranplant period, after the HBsAg seroconversion, 400 IU of hepatitis B immunoglobulin were applied intramuscularly every 2 weeks, and daily nucleos(t)ide analogs were continued as prophylaxis. The HBV recurrence was defined as the presence of HBsAg in serum. Patients were screened for alpha-fetoprotein levels and imaging for evaluation of HCC recurrence.

RESULTS

The average follow-up period was 26 (2-65) months. Fifty-four patients had HCC. The HCC recurrence was observed in 12 patients during the follow-up period. The HBV recurrence was observed in four patients. Three of the patients who developed HBV recurrence had liver transplantation due to HCC. Tumor recurrence was observed 1.4-12 months following the HBV recurrence. The HCC recurrence within the Milan criteria and beyond the Milan criteria was 0% vs. 28.4 % in the first year and 3.4% vs. 47.5% in the third year. The cumulative incidence of the HBV recurrence was 2.8% and 3.7% for the first year and 3.7% for the third year. The HBV recurrence was more frequently detected in patients with HCC (p=0.048), especially with HCC beyond the Milan criteria (p=0.044).

CONCLUSION

The HBV recurrence should be evaluated as a predictor of the HCC recurrence in patients who underwent liver transplantation due to HCC with exceeding Milan criteria.

Proposed model for the prediction of intrahepatic covalently closed circular DNA level in patients with chronic hepatitis B

AIM

We sought to create a prediction model for intrahepatic covalently closed circular DNA (IH-cccDNA) level in chronic hepatitis B (CHB) patients and to validate the model's predictive accuracy.

METHODS

Patients who did not receive previous nucleoside analogue (NA) therapy were assigned to the training cohort (n = 57), and those who received previous NA therapy were assigned to the validation cohort (n = 69). Factors linked to IH-cccDNA levels in the training cohort were analyzed and a formula to predict IH-cccDNA levels was constructed. Next, the reproducibility of that formula was assessed.

RESULTS

In the multivariate analysis for the prediction of IH-cccDNA level in the training cohort, fasting blood sugar (FBS) (P = 0.0227), hepatitis B e antigen (HBeAg) (P = 0.0067) and log10 (HB surface antigen [HBsAg]) (P = 0.0497) were significant, whereas HB core-related antigen (HBcrAg) tended to be significant (P = 0.0562). The formula was constructed and named the FBS-cres score based on the variables used (FBS, HBcrAg, HBeAg, and HBsAg). The FBS-cres score was calculated as: 3.1686 - (0.0148 × FBS) + (0.1982 × HBcrAg) + (0.0008168 × HBeAg) + (0.1761 × log10 (HBsAg)). In the training cohort, a significant correlation was noted between HBcrAg and IH-cccDNA levels (P < 0.0001, r = 0.67), whereas the FBS-cres score was more closely correlated to IH-cccDNA level (P < 0.0001, r = 0.81). In the validation cohort, significant correlation was found between HBcrAg and IH-cccDNA levels (P = 0.0012, r = 0.38), whereas the FBS-cres score was more closely linked to IH-cccDNA levels (P < 0.0001, r = 0.51). Similar tendencies were observed in all subgroup analyses.

CONCLUSION

Our proposed model for the prediction of IH-cccDNA level could be helpful in CHB patients.

Sequence-encoded quantitative invader assay enables highly sensitive hepatitis B virus DNA quantification in a single tube without the use of a calibration curve

Absolute quantification of HBV-DNA by sequence-encoded Quantitative Invader assay in a single tube without using calibration curves.

Reduced HBV cccDNA and HBsAg in HBV-associated hepatocellular carcinoma tissues

Approximately 50% of hepatocellular carcinoma (HCC) is attributable to chronic infection with hepatitis B virus (HBV). Serum hepatitis B surface antigen (HBsAg) is an important diagnostic marker of HBV infection, whereas intrahepatic HBV covalently closed circular DNA (cccDNA) is a surrogate marker of HBV persistence. This study aimed to investigate relationships between serum HBsAg, intrahepatic HBsAg, and intrahepatic cccDNA in HBV-associated HCC. Intrahepatic HBsAg was determined by immunohistochemistry in matched non-cancerous and HCC tissues from 88 patients; 56 patients (63.64%) were serum HBsAg positive. In serum HBsAg-positive group, intrahepatic HBsAg was positive staining in 73.2% of non-cancerous tissues, but only in 10.7% of HCC tissues. Significant correlation between serum HBsAg and intrahepatic HBsAg was observed in non-cancerous tissues (p < 0.001), but not in HCC tissues (p = 0.415). Absolute quantification of intrahepatic cccDNA was performed by droplet digital PCR in tissues from 30 patients; 18 patients (60%) were serum HBsAg positive. In serum HBsAg-positive group, intrahepatic cccDNA was detected in 66.66% of non-cancerous tissues, but only in 5.55% of HCC tissue; intrahepatic cccDNA levels in non-cancerous tissues were significantly higher than those in HCC tissues (p < 0.001), and correlated with serum HBsAg (p < 0.01). Significant correlations between intrahepatic HBsAg and intrahepatic cccDNA were found in both non-cancerous tissues (p < 0.01) and HCC tissues (p < 0.05). We concluded that HBV cccDNA and intrahepatic HBsAg in HBV-associated HCC tissues were significantly reduced, as compared with matched non-cancerous tissues. This warrants further investigation into the impacts and the cause(s) of cccDNA reduction in HBV-associated HCC tissues, which might yield novel immune-related therapy for HBV-associated HCC.

A Highly Sensitive and Robust Method for Hepatitis B Virus Covalently Closed Circular DNA Detection in Single Cells and Serum

Despite implications of persistence of hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) in the development of hepatocellular carcinoma (HCC), little is known about serum cccDNA in HBV-infected diseases. We developed a cccDNA-selective droplet digital PCR (ddPCR) to assess cccDNA content and dynamics across different stages of HCC development. One hundred forty-seven serum samples and 35 formalin-fixed, paraffin-embedded tumor tissues were derived from patients with HCC or HBV hepatitis/cirrhosis. After specific amplification and selective digestion, probe-based ddPCR was used to quantify cccDNA copy numbers in single cells and clinical samples. The cccDNA in single HepG2.2.15 cells ranged from 0 to 10.8 copies/cell. Compared with non-HCC patients, HCC patients showed a higher cccDNA-positive rate (89.9% versus 53.2%; P = 4.22 × 10^-6) and increased serum cccDNA contents (P = 0.002 and P = 0.041 for hepatitis and cirrhosis patients, respectively). Serum cccDNA ranged from 84 to 1.07 × 10⁵ copies/mL. Quantification of serum cccDNA and HBV-DNA was an effective way to discriminate HCC patients from non-HCC patients, with areas under the curve of receiver operating characteristic of 0.847 (95% CI, 0.759-0.935; sensitivity, 74.5%; specificity, 93.7%). cccDNA-selective ddPCR is sensitive to detect cccDNA in single cells and different clinical samples. Combined analysis of serum cccDNA and HBV-DNA may be a promising strategy for HBV-induced HCC surveillance and antiviral therapy evaluation.

Prognosis of preoperative positron emission tomography uptake in hepatectomy patients

Purpose

Preoperative F-18-fluoro-2-deoxy-glucose positron emission tomography (18F-FDG PET) imaging results appear to predict tumor recurrence and patient survival. The present study compared outcomes between PET-positive and PET-negative groups with HBV-related hepatocellular carcinoma (HCC) who underwent curative hepatectomy and assessed the prognostic value of positive PET-CT for HCC recurrence and death.

Methods

This study included patients who underwent liver resection of solitary HCC between 2007 and 2014 based on preoperative radiological images. There were 133 patients in the PET-positive group and 93 in the PET-negative group.

Results

There were no statistically significant differences in baseline, perioperative, or pathologic characteristics between the 2 groups except HBsAg titer, tumor size, and presence of bile duct tumor thrombi. Multivariate analysis showed that tumor size >3.5 cm and HBsAg titer >1,000 cutoff index were predisposing factors of positive PET-CT. Disease-free survival and overall survival rate at 1, 3, and 5 years were 76.3%, 64.4%, 60.3% and 96.8%, 91.1%, 85.1% in the PET-negative group, respectively, compared with 70.7%, 62.2%, 58.9% and 98.5%, 97.0%, 97.0% in the PET-positive group (P = 0.547 and P = 0.046). Multivariate analysis showed that positive PET-CT was closely associated with increased patient survival, but was not related to HCC recurrence.

Conclusion

These results suggest that positive PET findings are not a predisposing factor for recurrence of HBV-related HCC patients, but appear to be associated with improved patient survival. Further prospective studies are needed to confirm the prognostic value of 18F-FDG PET in these patients.

Hepatitis B Virus Pregenomic RNA in Hepatocellular Carcinoma: A Nosological and Prognostic Determinant

Hepatitis B virus (HBV) is a major cause of hepatocellular carcinoma (HCC). However, very little is known about the replication of HBV in HCC tissues. We analyzed viral and cellular parameters in HCC (T) and nontumor liver (NT) samples from 99 hepatitis B surface antigen (HBsAg)-positive, virologically suppressed patients treated by tumor resection or liver transplantation. We examined total HBV DNA and RNA as well as covalently closed circular DNA (cccDNA) and pregenomic RNA (pgRNA), which are considered as markers of active HBV replication. Total HBV DNA and RNA were detected in both T and NT samples in a majority of cases, but only a subset of tumors harbored detectable levels of HBV cccDNA and pgRNA (39% and 67%) compared to NT livers (66% and 90%; P < 0.01). Further evidence for HBV replication in tumor tissues was provided by sequencing of the X gene derived from episomal forms, showing that HBV genotypes differed between T and matched NT samples in 11 cases. The detection of pgRNA and cccDNA in tumors was correlated to the absence of tumorous microvascular invasion and to better patient survival. Analysis of gene expression profiles by Agilent microarrays revealed that pgRNA-positive HCCs were characterized by low levels of cell cycle and DNA repair markers and expression of the HBV receptor, sodium taurocholate cotransporting polypeptide, indicating well-differentiated tumors.

CONCLUSION

HCC replicating HBV represents a subtype of weakly invasive HCC with a transcriptomic signature. pgRNA originating from nonintegrated, complete HBV genomes is a sensitive marker for viral replication and prognosis. (Hepatology 2018;67:86-96).

Detection of HBV DNA and antigens in HBsAg-positive patients with primary hepatocellular carcinoma

BACKGROUND

Hepatitis B virus (HBV) markers include HBV deoxyribonucleic acid (DNA) and HBV antigens. The former involves HBV covalently closed circular DNA (cccDNA) as well as total HBV DNA, whereas the latter involves HBsAg, HBcAg, and HBx.

METHODS

Samples of tumor and adjacent non-tumor liver tissue were collected from 28 HBV-associated HCC patients. Intrahepatic total HBV DNA and cccDNA were measured using the real-time PCR Taqman assay. HBV antigens in hepatocytes were detected using immunohistochemical staining. Intrahepatic levels of total HBV DNA or cccDNA in HCC patients with different intrahepatic HBV antigen expression patterns were compared, and the correlation between serum HBV DNA and intrahepatic HBV DNA was analyzed.

RESULTS

No significant differences in intrahepatic cccDNA levels were observed between tumor and non-tumor liver tissue (median -3.00 vs. -2.30 log copies/cell, P=0.298). However, the tumor tissue had significantly higher levels of total HBV DNA (median -0.60 vs. -1.24 log copies/cell, P=0.045) but significantly lower proportion of intrahepatic HBV DNA in the form of cccDNA (median 0.25% vs. 4%, P=0.023) than the corresponding values in the non-tumor tissue. Also, HBV antigen levels were lower in the tumor tissue than in the non-tumor tissue. Analysis of the correlation between serum HBV DNA and intrahepatic HBV DNA indicated that the viral status in the tumor tissue was more complicated in HBV-HCC patients-the detected serum HBV DNA failed to accurately reflect intrahepatic viral load.

CONCLUSION

HBV DNA may play an important role in hepatocarcinogenesis, and cccDNA was not the predominant form of HBV DNA in the tumor tissue.

Detection of HBV Covalently Closed Circular DNA

Chronic hepatitis B virus (HBV) infection affects approximately 240 million people worldwide and remains a serious public health concern because its complete cure is impossible with current treatments. Covalently closed circular DNA (cccDNA) in the nucleus of infected cells cannot be eliminated by present therapeutics and may result in persistence and relapse. Drug development targeting cccDNA formation and maintenance is hindered by the lack of efficient cccDNA models and reliable cccDNA detection methods. Southern blotting is regarded as the gold standard for quantitative cccDNA detection, but it is complicated and not suitable for high-throughput drug screening, so more sensitive and simple methods, including polymerase chain reaction (PCR)-based methods, Invader assays, in situ hybridization and surrogates, have been developed for cccDNA detection. However, most methods are not reliable enough, and there are no unified standards for these approaches. This review will summarize available methods for cccDNA detection. It is hoped that more robust methods for cccDNA monitoring will be developed and that standard operation procedures for routine cccDNA detection in scientific research and clinical monitoring will be established.

The relationship between HBcrAg and HBV reinfection in HBV related post-liver transplantation patients

BACKGROUND

Post-transplant hepatitis B virus (HBV) reinfection is one of the major problems facing patients who undergo HBV-related liver transplantation (LT). We analyzed the clinical impact of serum hepatitis B core-related antigen (HBcrAg) on HBV reinfection in post-LT patients with HBV-related liver diseases.

METHODS

Serum hepatitis B surface antigen (HBsAg), HBV DNA, and HBcrAg were measured over time in 32 post-LT patients. Twenty-one out of 32 patients had HCC at LT. The effects of HBcrAg, hepatocellular carcinoma (HCC) recurrence, and HBs gene mutation on HBV reinfection and withdrawal from hepatitis B immune globulin (HBIG) were analyzed.

RESULTS

Sixteen out of 32 patients (50 %) were positive for HBcrAg even though only six patients were thought to have experienced HBV reinfection based on reappearance of either HBV DNA or HBsAg during a median follow-up time of 75 months. Three of these six patients who became re-infected with HBV experienced HCC recurrence after LT. The HBV DNA reappearance rate was significantly higher in patients with HCC recurrence after LT (p < 0.001). Two HBV re-infected patients without HCC recurrence had HBs gene mutations G145R and G145A, respectively. Anti-HBs antibody development rate by HB vaccination was similar between HBcrAg-positive and negative patients (p = 0.325).

CONCLUSIONS

HBV reinfection is more common than is usually considered based on conventional measurement of HBsAg and HBV DNA. HCC recurrence and mutations in the HBV S gene were associated with HBV reinfection after LT.

Quantitative intrahepatic HBV cccDNA correlates with histological liver inflammation in chronic hepatitis B virus infection

BACKGROUND

The aim of this study was to determine the role of baseline hepatitis B virus (HBV) forming covalently closed circular DNA (HBV cccDNA) in liver inflammation in patients infected with HBV with serum alanine aminotransferase (ALT) levels under two times the upper limit of normal (2×ULN).

METHODS

After liver biopsy and serum virological and biochemical marker screening, patients diagnosed with chronic HBV infection with serum ALT levels under 2×ULN and histological liver inflammation of less than grade G2 were prospectively recruited into this study. Recruitment took place between March 2009 and November 2010 at the Center of Infectious Disease, Sichuan University. Patient virological and biochemical markers, as well as markers of liver inflammation, were monitored.

RESULTS

A total of 102 patients were recruited and 68 met the inclusion criteria; the median follow-up was 4.1 years (range 3.9-5.2 years). During follow-up, 41 patients (60.3%) exhibited signs of inflammation. Baseline HBV cccDNA >1 copy/cell (odds ratio 9.43, p=0.049) and liver inflammation grade ≥G1 (odds ratio 5.77, p=0.046) were both independent predictors of liver inflammation.

CONCLUSIONS

A higher baseline intrahepatic HBV cccDNA level may increase the risk of liver inflammation. Further investigations will be required to validate HBV cccDNA as an intrahepatic virological marker of patients who require extended outpatient management.

Hepatitis B virus full-length genomic mutations and quasispecies in hepatocellular carcinoma

BACKGROUND AND AIM

Hepatitis B virus (HBV) full-length genomic mutations and quasispecies characteristics in hepatocellular carcinoma (HCC) were investigated.

METHODS

Hepatitis B virus DNA was extracted from the tumor and non-tumor tissues of 16 HCC patients. Overlapping DNA fragments covering the entire HBV genome were amplified and sequenced. To study HBV sequence at the quasispecies level, the preS region was amplified and clonally sequenced. HBV mutation profiles, quasispecies complexity and diversity, and phylogenetic characteristics were assessed.

RESULTS

Fourteen patients had full-length HBV amplification. Hot-spot mutations at HBx aa130-131 and pre-S deletions were detected in 13 (93%) and 6 (43%) patients, respectively. Deletions in the X/preC/C regions were more frequently detected in the tumor than in the non-tumor tissues (P = 0.031). Compared with the non-tumor tissues, the tumor tissues had a lower quasispecies complexity (P = 0.014 and 0.043, at the nucleotide and amino acid levels, respectively) and diversity (P = 0.048 and 0.022, at the nucleotide and amino acid levels, respectively). Phylogenetic analysis showed that HBV sequences derived from tumor and non-tumor tissues were separately clustered, suggesting the occurrence of compartmentalization, which was confirmed by the correlation coefficient testing on both the number and length of branches of viral populations (all P < 0.02).

CONCLUSIONS

Hepatitis B virus mutation patterns in HCC tumor tissues and non-tumor tissues were different. HBV quasispecies within the preS region were compartmentalized, and tumor tissues had a lower genome complexity and diversity. Our study suggests HBV evolution is conditioned by the differential host cellular environment in HCC tumors.

Impact of non-neoplastic vs intratumoural hepatitis B viral DNA and replication on hepatocellular carcinoma recurrence

Background:

This study aims to determine the impact of intracellular hepatitis B virus (HBV) DNA, covalently closed circular DNA (cccDNA) and viral replicative activity in both tumour and non-neoplastic liver on prognosis and to determine the relationship of viral replicative activity and Ishak fibrosis in predicting outcome following resection.

Methods:

A total of 99 prospectively enrolled patients treated with primary liver resection for HBV-HCC are included. Intracellular HBV DNA and cccDNA were quantitated by real-time PCR. The RNA-sequencing (RNA-seq) was performed in a subset of 21 patients who had either minimal liver fibrosis (Ishak stages 0–2) or end-stage fibrosis (Ishak stage 6).

Results:

Tumour tissue contained a lower cccDNA copy number compared with paired non-neoplastic liver, and larger tumours (>3 cm) had less cccDNA compared with small tumours (⩽3 cm). High viral replicative activity in non-neoplastic liver was associated with higher HCC recurrence rate independent of Ishak fibrosis stage. Genes correlated with viral replicative activity in non-neoplastic liver (620 genes) were distinct from those associated with end-stage fibrosis (1226 genes). Genes associated with viral replicative activity were preferentially distributed in regions on chr3, chr16 and chr19.

Conclusions:

Viral replicative activity in non-neoplastic liver is associated with HCC recurrence through mechanisms that are distinct from and independent of Ishak fibrosis stage.

Association of Hepatitis B Virus Covalently Closed Circular DNA and Human APOBEC3B in Hepatitis B Virus-Related Hepatocellular Carcinoma

Chronic Hepatitis B Virus (HBV) infections can progresses to liver cirrhosis and hepatocellular carcinoma (HCC). The HBV covalently-closed circular DNA cccDNA is a key to HBV persistence, and its degradation can be induced by the cellular deaminase APOBEC3. This study aimed to measure the distribution of intrahepatic cccDNA levels and evaluate the association between levels of cccDNA and APOBEC3 in HCC patients. Among 49 HCC patients, 35 matched cancerous and contiguous noncancerous liver tissues had detectable cccDNA, and the median intrahepatic cccDNA in the cancerous tissues (CT) was significantly lower than in the contiguous noncancerous tissues (CNCT) (p = 0.0033). RCA (rolling circle amplification), followed by 3D-PCR identified positive amplification in 27 matched HCC patients. Sequence analysis indicated G to A mutations accumulated to higher levels in CT samples compared to CNCT samples, and the dinucleotide context showed preferred editing in the GpA context. Among 7 APOBEC3 genes, APOBEC3B was the only one up-regulated in cancerous tissues both at the transcriptional and protein levels (p < 0.05). This implies APOBEC3B may contribute to cccDNA editing and subsequent degradation in cancerous tissues.

Epigenetically regulated miR-449a enhances hepatitis B virus replication by targeting cAMP-responsive element binding protein 5 and modulating hepatocytes phenotype

Cellular microRNAs (miRNAs) are able to influence hepatitis B virus (HBV) replication directly by binding to HBV transcripts or indirectly by targeting cellular factors. Here, we investigate the effect of epigenetically regulated miR-449a on HBV replication and the underlying mechanisms. miR-449a expression was lower in human hepatocellular carcinoma (HCC) cells than in primary hepatocytes and could be induced by trichostatin A. Ectopic miR-449a expression in HCC cells strongly enhanced HBV replication, transcription, progeny virions secretion, and antigen expression in a dose-dependent manner. miR-449a directly targeted cAMP-responsive element binding protein 5 (CREB5), which in turn induced the expression of farnesoid X receptor α (FXRα), a transcription factor that facilitates HBV replication. CREB5 knockdown and overexpression demonstrated that it is a negative regulator of HBV replication. Additionally, miR-449a overexpression inhibited proliferation, caused cell cycle arrest, and promoted HCC cell differentiation. The results indicated that epigenetically regulated miR-449a targets CREB5 to increase FXRα expression, thereby promoting HBV replication and gene expression. Our findings provide a new understanding of the role of miRNAs in HBV replication.

Dynamic Characteristics of Serum Hepatitis B Surface Antigen in Chinese Chronic Hepatitis B Patients Receiving 7 Years of Entecavir Therapy

BACKGROUND

The ultimate goal of hepatitis B treatment is hepatitis B surface antigen (HBsAg) seroclearance. Several factors have been suggested to be associated with the rate of HBsAg reduction in antiviral-naive or lamivudine therapy cohorts. However, there are few studies evaluating the factors during long-term entecavir (ETV) therapy. In the present study, we aimed to evaluate the factors to predict the outcome of ETV therapy for 7 years.

METHODS

A total of 47 chronic hepatitis B (CHB) patients treated with ETV monotherapy were included in this study. Liver biochemistry, hepatitis B virus (HBV) serological markers, serum HBV DNA, and HBsAg titers were tested at baseline, 3 months, 6 months, and yearly from 1 to 7. The associations between factors and HBsAg reduction were assessed using multivariate tests with repeated measure analysis of variance.

RESULTS

At baseline, serum HBsAg levels showed a positive correlation with baseline HBV DNA levels (r = 0.625, P < 0.001). The mean HBsAg titers after ETV treatment were significantly lower than the baseline titers (P ranges from 0.025 to 0.000,000,6). The HBsAg reduction rate during the 1st year was greater compared to after 1 year of treatment (P < 0.05). Multivariate test showed that hepatitis B e antigen (HBeAg) seroclearance and/or HBsAg reduction ≥0.5 log10 IU/ml at 6 months had a high negative predictive value (96.77%) for HBsAg seroclearance (P = 0.002, P = 0.012, respectively).

CONCLUSIONS

The HBsAg reduction rate during the 1st year was greater than that after 1 year of treatment. Further, HBeAg status and HBsAg levels at month 6 are the optimal factors for the early prediction of HBsAg seroclearance after long-term ETV therapy in CHB patients.

Clinical relevance of the study of hepatitis B virus covalently closed circular DNA

Hepatitis B virus (HBV) remains a public health concern with 240 million people affected worldwide. HBV is an hepadnavirus that replicates its genome in hepatocytes. One of the key steps of the viral life cycle is the formation of cccDNA - covalently closed circular DNA - in the nucleus, the equivalent of a viral mini-chromosome that acts as a template for subsequent virus replication. Current antiviral medications are not effective in eradicating cccDNA, which can persist in the infected liver even in the absence of detectable HBV DNA or HBsAg in the blood. cccDNA cannot be measured in serum, and few surrogate markers have been proposed. Persistent cccDNA has been associated with various clinical events, including viral reactivation induced by immunosuppressive therapies, HBV recurrence after liver transplantation and hepatocellular carcinoma (HCC). cccDNA remains the main target to achieve a cure of HBV infection, thus extensive efforts are being made to develop new antiviral concepts to degrade or silence cccDNA.

Association between HBV Pre-S mutations and the intracellular HBV DNAs in HBsAg-positive hepatocellular carcinoma in China

This study aimed to investigate the association between HBV mutations and intrahepatic HBV status and to determine the clinical features and the contribution of HBV mutations to postoperative prognosis for hepatocellular carcinoma (HCC) patients with HBsAg (+) in China. Using TaqMan fluorescent real-time PCR, HBV covalently closed circular DNA (cccDNA) and total DNA (tDNA) were both quantified in 106 pairs of tumor tissues (TT) and adjacent non-tumor tissues (ANTT) obtained from HCC patients who received no antiviral treatment before surgical treatment. The prevalence of 19 hot spot mutations was evaluated by Sanger sequencing. HBV cccDNA and tDNA were lower in TT than in ANTT. The loads of cccDNA and tDNA in ANTT were associated with serum HBV DNA and HBeAg. Three Pre-S mutants (A2962G and C2964A in Pre-S1 and C105T in Pre-S2) were associated with higher tumor cccDNA levels (P < 0.05), and A2962G/C2964A mutants were associated with higher AFP levels. This would assist to disclose the virological features, to implement a more clinically personalized therapy and to improve the prognosis of HBV-related HCC patients.

The intracellular HBV DNAs as novel and sensitive biomarkers for the clinical diagnosis of occult HBV infection in HBeAg negative hepatocellular carcinoma in China

This study aimed to investigate the virological status in liver (both tumor and adjacent non-tumor tissue), the clinical features and the contribution of occult HBV infection (OBI) to postoperative prognosis in HBeAg-negative(−) hepatocellular carcinoma (HCC) patients in China. Using quantitative TaqMan fluorescent real-time PCR assays, HBV covalently closed circular DNA (cccDNA) and total DNA (tDNA) were both quantified in 11 (HBsAg(−)) and 57 (HBsAg-positive(+)) pairs of tumor tissue (TT) and adjacent non-tumor tissue (ANTT) obtained from HBeAg(−) HCC patients who received no antiviral treatment and were negative for anti-HCV before surgical treatment. Of 11 HBsAg(−) patients, 36% were with HBsAb(+) HBeAb(+) HBcAb(+). However, only 9% of the HBsAg(−) patients were HBsAb(−) HBeAb(+) HBcAb(+), which accounted for the majority (93%) in the HBsAg(+) group. TT and ANTT HBV tDNAs in 11 HCC patients with HBsAg (−) and HBeAg (−) were all detectable. HBV cccDNA and tDNA were all lower in the HBsAg(−) group than those in the HBsAg(+) group. By Kaplan-Meier analysis, patients with OBI were associated with a lower risk of cirrhosis and better overall survival (OS). The intracellular HBV DNAs, such as HBV cccDNA and tDNA are valuable biological markers for the diagnosis of occult HBV infection in HCC patients. This would assist the clinical implementation of a more personalized therapy for viral re-activation control and improve the survival rate of OBI patients.

Practical approach in hepatitis B e antigen-negative individuals to identify treatment candidates

The natural history of chronic hepatitis B is characterized by different phases of infection, and patients may evolve from one phase to another or may revert to a previous phase. The hepatitis B e antigen (HBeAg)-negative form is the predominant infection worldwide, which consists of individuals with a range of viral replication and liver disease severity. Although alanine transaminase (ALT) remains the most accessible test available to clinicians for monitoring the liver disease status, further evaluations are required for some patients to assess if treatment is warranted. Guidance from practice guidelines together with thorough investigations and classifications of patients ensure recognition of who needs which level of care. This article aims to assist physicians in the assessment of HBeAg-negative individuals using liver biopsy or non-invasive tools such as hepatitis B s antigen quantification and transient elastography in addition to ALT and hepatitis B virus DNA, to identify who will remain stable, who will reactivate or at risk of disease progression hence will benefit from timely initiation of anti-viral therapy.

Occult hepatitis B virus and hepatocellular carcinoma

Occult hepatitis B virus (HBV) infection (OBI) is a challenging pathobiological and clinical issue that has been widely debated for several decades. By definition, OBI is characterized by the persistence of HBV DNA in the liver tissue (and in some cases also in the serum) in the absence of circulating HBV surface antigen (HBsAg). Many epidemiological and molecular studies have indicated that OBI is an important risk factor for hepatocellular carcinoma (HCC) development. OBI may exert direct pro-oncogenic effects through the activation of the same oncogenic mechanisms that are activated in the course of an HBsAg-positive infection. Indeed, in OBI as in HBV-positive infection, HBV DNA can persist in the hepatocytes both integrated into the host genome as well as free episome, and may maintain the capacity to produce proteins-mainly X protein and truncated preS-S protein - provided with potential transforming properties. Furthermore, OBI may indirectly favor HCC development. It has been shown that the persistence of very low viral replicative activity during OBI may induce mild liver necro-inflammation continuing for life, and substantial clinical evidence indicates that OBI can accelerate the progression of liver disease towards cirrhosis that is considered the most important risk factor for HCC development.

Impact of postoperative hepatitis B virus reactivation in hepatocellular carcinoma patients who formerly had naturally suppressed virus

BACKGROUND AND AIM

Hepatitis B virus (HBV) replication detected before the resection of hepatocellular carcinoma (HCC) is to be controlled by antiviral agents. However, management strategy for patients with preoperatively undetectable HBV DNA without antiviral therapy is not clearly delineated. This study investigated viral reactivation after the liver resection in non-replicating HBV DNA-related HCC patients and its impact on the surgical outcome.

METHODS

From 198 patients that underwent liver resection due to HBV-related HCC, 101 patients who had serially checked serum HBV DNA were analyzed.

RESULTS

From 101 patients, 33 patients had baseline undetectable HBV DNA. Eleven patients (11/33, 33.3%) had viral replication after the liver resection. The postoperative viral reactivation (HR: 2.144; 95% CI: 1.122-4.097; P = 0.021), along with the existence of satellite nodules (HR: 3.034; 95% CI: 1.1.376-6.689; P = 0.006), existence of microvascular invasion (HR: 2.479; 95% CI: 1.303-4.718; P = 0.006), and HBeAg positivity (HR: 2.059; 95% CI: 1.155-3.670; P = 0.014) predicted recurrence after the surgery. Quantification of intrahepatic total and covalently closed circular DNA (cccDNA) was done in 14 patients whose baseline serum HBV DNA was undetectable without the use of antiviral agent. Amount of intrahepatic cccDNA expressed as copies/hepatocyte in patients with postoperative viral reactivation showed significantly higher than those in patients with sustained negative serum HBV DNA (P = 0.010).

CONCLUSIONS

This study shows that naturally suppressed preoperative HBV without application of antiviral agent does not ensure undetectable serum HBV after the surgery, and postoperative viral reactivation might be associated with HCC recurrence.

Prevention and risk factors of hepatitis B recurrence after living donor liver transplantation

BACKGROUND AND AIM

Without effective prophylaxis, liver transplantation (LT) for hepatitis B virus (HBV)-related liver disease is frequently complicated by severe and rapidly progressive HBV recurrence. The combination of low-dose hepatitis B immunoglobulin (HBIG) and the new nucleos(t)ide analog, entecavir, as prophylaxis for HBV recurrence after living-donor LT (LDLT) were analyzed.

METHODS

A total of 315 patients with positive hepatitis B surface antigen underwent LDLT at our transplant center between July 2003 and December 2011. Our protocol for post-transplantation HBV prophylaxis was a combination of low-dose HBIG and nucleos(t)ide analog.

RESULTS

During a median follow-up period of 49 months post-transplant, 10 patients (3.2%) had HBV recurrence, which was significantly related to hepatocellular carcinoma (HCC) at transplantation (P = 0.041) and post-LT antiviral agent (P < 0.001) in multivariate analysis. The level of HBV DNA and hepatitis B e antigen state at transplantation were not significant factors for HBV recurrence (P = 0.342 and P = 0.802, respectively). In 170 patients with HCC at LDLT, HCC recurrence was significantly related to HBV recurrence (P < 0.001). Among 10 patients with HBV recurrence, three are alive and two had lost hepatitis B surface antigen. The remaining seven patients died of HCC recurrence.

CONCLUSIONS

The combination of low-dose HBIG and nucleos(t)ide analogs is safe and effective for HBV prophylaxis after LDLT. As a post-LT antiviral treatment, entecavir is more effective than lamivudine. HCC at transplantation was significantly associated with HBV recurrence. HBV-related HCC patients who undergo LDLT require close virological monitoring.

Roles of microRNAs in the hepatitis B virus infection and related diseases

The hepatitis B virus (HBV) is a small enveloped DNA virus that belongs to the Hepadnaviridae family. HBV can cause acute and persistent infection which can lead to hepatocellular carcinoma (HCC). MicroRNAs (miRNAs) play a crucial role in the main cellular events. The dysregulation of their expression has been linked to the development of the cancer as well as to viral interference. This chapter will describe the involvement of miRNAs in the case of HBV infection and their implication in the development of the HBV-related diseases.

Comparison of hepatitis B prophylactic outcomes in living donor liver transplantation recipients who meet the Milan or UCSF criteria

BACKGROUND

The tumor burden before liver transplantation indicates that hepatitis B virus (HBV) may hide in the extrahepatic and micrometastatic sites which serve as a source of HBV replication. Currently, many liver transplant centers, especially in Western countries, use the Milan or UCSF criteria to select patients with hepatocellular carcinoma for liver transplantation. This study was undertaken to compare the HBV prophylactic outcomes in two groups of living donor liver transplantation (LDLT) recipients. Patients in group A met the Milan criteria and those in group B exceeded the Milan criteria but were within the UCSF criteria.

METHODS

A database of adult-to-adult right-lobe LDLT performed at our institution for HBV-related hepatocellular carcinoma within the Milan or UCSF criteria between June 2002 and May 2012 was used to compare the HBV prophylactic outcomes between patients within the Milan criteria (group A, 41 patients) and those exceeding the Milan criteria but within the UCSF criteria (group B, 19 patients).

RESULTS

The 1-, 3-, and 5-year survival rates were similar between groups A and B (87.8%, 85.1% and 74.0% vs 73.3%, 61.1% and 61.1%, respectively, P=0.067). HBV recurred in 1 patient in 3.1 months after LDLT in group A and in 2 patients in group B (1 in 11.9 months and 1 in 24.1 months after LDLT). The 1-, 3-, and 5-year HBV recurrence rates were 2.6%, 2.6% and 2.6% in group A, and 7.3%, 17.9% and 17.9% in group B, respectively (P=0.118).

CONCLUSION

LDLT recipients who exceed the Milan criteria but remain within the UCSF criteria may have post-transplant HBV prophylactic outcomes similar to those who meet the Milan criteria.

Hepatitis B surface antigen inhibits MICA and MICB expression via induction of cellular miRNAs in hepatocellular carcinoma cells

Hepatitis B surface antigen (HBsAg) seropositivity is an important risk factor for hepatocellular carcinoma (HCC), and HBsAg-transgenic mice have been reported to spontaneously develop HCC. The major histocompatibility complex class I-related molecules A and B (MICA and MICB) are NKG2D ligands that play important roles in tumor immune surveillance. In the present study, we found that HBsAg overexpression in HepG2 cells led to upregulation of 133 and downregulation of 9 microRNAs (miRNAs). Interestingly, several HBsAg-induced miRNAs repressed the expression of MICA and MICB via targeting their 3'-untranslated regions. In addition, the expression of MICA and MICB was significantly reduced upon HBsAg overexpression, which was partially restored by inhibiting the activities of HBsAg-induced miRNAs. Moreover, HBsAg-overexpressing HCC cells exhibited reduced sensitivity to natural killer cell-mediated cytolysis. Taken together, our data suggest that HBsAg supresses the expression of MICA and MICB via induction of cellular miRNAs, thereby preventing NKG2D-mediated elimination of HCC cells.

Long-term outcome of hepatitis B virus-related Chronic Hepatitis under protracted nucleos(t)ide analogues

Long-term outcome of patients with chronic hepatitis B virus (HBV) infection under continuous nucleos(t)ide analogues (NUCs) has been poorly elucidated. We enrolled 121 anti-HBe-positive patients into a prospective surveillance programme while on (>36 months) NUCs therapy. HBV-DNA clearance, add-on therapy and safety were evaluated. Development of cirrhosis, events of liver decompensation and hepatocellular carcinoma (HCC) during the follow-up were the main endpoints, as the complication-free survival. At baseline, 74 patients (61%) had chronic hepatitis, the remainders a cirrhotic liver. HBV-DNA levels >38 000 IU/mL were discovered in 103 patients. At enrolment, 79 patients were naïve to NUCs treatment. Lamivudine monotherapy (n = 70) or a different NUC (n = 51) was administered. At month 6 of therapy, HBV-DNA clearance was documented in 88 patients (73%). Treatment schedule was modified in 52 patients due to breakthrough or suboptimal response. During a mean follow-up of 6 ± 3 years, viral clearance was achieved in the majority of patients. Ten of 74 patients (13.5%) with chronic hepatitis progressed to cirrhosis, 1 patient developed a HCC. In the 47 patients with cirrhosis at presentation, HCC occurred in 14 (30%) and liver decompensation in 5 (11%). The 5 and 10-year event-free survivals were, respectively, 89.3% (95% CI, 81.7 -96.9) and 75.6% (95% CI, 61.5 -89.7) for patients with chronic hepatitis, and 70.2% (95% CI, 56.3 -84.1) and 40.4% (95% CI, 16.9 -63.9) for those with cirrhosis. Protracted, effective treatment with oral NUCs affects the natural history of chronic HBV infection by reducing the incidence of cirrhosis and risk of complications, but does not guarantee against the development of HCC in cirrhosis at presentation.

Quantification of periodontopathic bacteria in saliva using the invader assay

When quantifying periodontopathic bacteria, it is important to use a convenient method that does not produce false negative results. The Invader assay is a convenient method because it does not involve gene amplification. The purpose of this study was to evaluate the validity of the Invader assay to quantify periodontopathic bacteria. The Invader technology was applied in quantifying five periodontopathic bacteria (Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Prevotella intermedia, and Treponema denticola). The Invader assay produced a linear quantitative detection range over concentrations spanning seven exponential values, with a detection limit of 10(3.7) copies/tube and intra-day and inter-day variance of 0.1% to 4.7% and 0.1% to 3.4%, respectively, in quantifying five periodontopathic bacteria. We compared the results of the Invader assay with those of real-time polymerase chain reaction (PCR) performed for quantifying five periodontopathic bacteria in 22 patients with periodontitis. Among the Invader-detectable bacterial strains of each species, significant correlations were observed in the counts of concerned bacterial species between these two methods, with correlation coefficients ranging from 0.757 to 0.996. This study validated repeatability and reproducibility of the Invader assay in quantifying periodontopathic bacteria and demonstrated consistent agreement between the Invader assay and real-time PCR in quantifying periodontopathic bacteria.

FAM172A induces S phase arrest of HepG2 cells via Notch 3

Our previous results revealed that FAM172A was significantly downregulated in liver tissue from hepatocellular carcinoma or cirrhotic patients. The present study was designed to elucidate the regulatory role of FAM172A in HepG2 cells. In order to determine the expression of the FAM172A protein, western blot analysis was performed. Confocal laser scanning technique was used to observe the localization of FAM172A in HepG2 cells. Surface plasmon resonance experiments were used to determine the binding activity of FAM172A and active single sugar and Ca2+. The cell cycle progression of HepG2 cells was assessed by flow cytometry. The FAM172A protein was localized in the endoplasmic reticulum of HepG2 cells. This protein was moderately expressed in normal liver tissue, but was significantly decreased in liver tissue of patients with chronic hepatitis B When co-cultured with the FAM172A recombinant protein, HepG2 cells exhibited complete cell cycle arrest in the S phase at a high concentration (100 ng/ml). Proliferation of HepG2 cells treated with the FAM172A recombinant protein was prominently inhibited compared with that of the control cells. Western blot analysis showed that upregulation of Notch 3 and cyclin E may be related with the cell cycle control. Our results indicate that FAM172A may be a novel tumor-suppressor gene, which plays an important role in cell cycle control and tumor cell proliferation. G1/S phase arrest may be mediated, at least partially, by the Notch 3 signaling pathway.