Frequent integration of hepatitis B virus DNA in noncancerous liver tissue from hepatocellular carcinoma patients

To investigate the relationship between hepatocarcinogenesis and integration of hepatitis B virus (HBV) DNA in the cellular DNA of the liver, we studied the integration of HBV DNA in various noncancerous regions of the liver from 31 patients using Southern blot analysis. Of 13 patients without hepatocellular carcinoma (HCC), 4 had heterogeneously integrated HBV DNA. Of the latter four patients, two had chronic liver disease, and two had nonspecific histological changes. In contrast, integration of HBV DNA was found in noncancerous tissue from 11 of 18 patients with HCC. In eight patients, homogeneous integration was found in noncancerous tissue, and restriction fragments of integrated HBV DNA were different from those found in cancerous tissue. Moreover, integration of HBV DNA was found in all portions examined from the same liver, and homogeneously integrated HBV DNA showed different restriction patterns in different areas. These results suggest that integration of HBV DNA may occur in heterogeneous sites of cellular DNA before hepatocarcinogenesis. Subsequently, multi-focal clonal populations develop from these hepatocytes, especially frequently in the case of HCC. Integrated HBV DNA may play an important role in the clonal growth of hepatocytes, although the development of HCC requires additional factors.     

Frequent detection of hepatitis B virus DNA in hepatocellular carcinoma of patients with sustained virologic response for hepatitis C virus

Hepatocellular carcinoma (HCC) develops several years after the eradication of hepatitis C virus (HCV) by interferon therapy. Risk factors for the development of HCC are only partly understood. To elucidate the role of occult hepatitis B virus (HBV) infection in hepatocarcinogenesis in patients with sustained virologic response, the prevalences of HBV‐related makers were examined. Study group comprised 16 patients with sustained virologic response (group A) and 50 with HCV (group B). Anti‐HBc and anti‐HBs in serum were examined by enzyme‐linked immunoassay. HBV DNA in liver was examined by nested polymerase chain reaction, using primers specific for genes encoding for HBx, HBsAg, HBcAg, and HBV cccDNA. Sequence of the amplified HBV DNA for ‘a’ determinant of HBsAg was determined in HCC. Anti‐HBc was positive in 10 of 16 in group A and 25 of 50 in group B. HBV DNA in liver was detected in 12 of 16 in group A and 21 of 50 in group B (P = 0.044). In group A, HBV DNA in liver was detected frequently in patients without cirrhosis and in those with a longer period from the time of HCV eradication to the development of HCC. Mutation in ‘a’ determinant of HBsAg was found in three HCC of group A. Occult HBV infection may be one of the most important risk factors in hepatocarcinogenesis of Japanese patients with sustained virologic response. J. Med. Virol. 81:1009–1014, 2009. © 2009 Wiley‐Liss, Inc.     

慢性乙型肝炎患者HBV cccDNA定量方法的建立及应用

目的 建立慢性乙型肝炎患者HBV cccDNA荧光定量检测方法 ,并检测慢性乙型肝炎患者血清中HBV cccDNA含量.方法 根据HBV DNA结构特点,于HBV cicada缺口两侧高度保守区域设计巢式PCR引物和探针,并优化PCR反应条件;选取175例慢性乙型肝炎患者,提取抗病毒治疗前后血清DNA,以不降解质粒的ATP依赖的DNA酶(PSAD)进行酶切,进行rcDNA定量检测;分析影响血清HBV cccDNA检出率的相关因素,探讨血清HBV cccDNA载量与慢性乙型肝炎患者临床特征的关系.结果 慢性乙型肝炎患者血清中可检测到HBV cccDNA.血清HBV cccDNA检出率与血清HBV DNA载量相关.HBeAg阳性慢性乙肝患者血清HBV cccDNA载量高于HBeAg阴性慢性乙肝患者.结论 本方法 具有较好的敏感性,可用于HBV cccDNA的检测.     

Detection of hepatitis B virus DNA in hepatocellular carcinoma

DNA-DNA hybridization was used to examine tissue from 31 patients with hepatocellular carcinoma (HCC) in Taiwan for the presence of the hepatitis B virus genome. Twenty-four of the DNA samples had discrete high molecular weight bands when cut with HindIII and hybridized with a radiolabelled HBV DNA probe, and similar results were obtained with 25 of the samples when cut with EcoRI. Thus integrated HBV DNA was present in almost 80% of the specimens. None of the samples had a similar pattern and most contained HBV DNA integrated at multiple sites. Seventeen out of 19 HBsAg carriers and one out of two patients with anti-HBs were found to have integrated HBV DNA in the tumour tissue, providing further evidence of the strong association between HBV infection and development of hepatocellular carcinoma.     

Real-time PCR for detection and quantitation of hepatitis B virus DNA

A sensitive and reproducible real-time PCR assay based on TaqMan technology was developed for the detection and quantitation of hepatitis B virus (HBV) DNA in serum, and compared with an "in-house" qualitative PCR assay. HBV DNA was measured in 125 serum samples from 76 hepatitis B patients, consisting of 22 patients with an acute infection, 20 patients with a previous history of hepatitis B infection, and 34 patients with a chronic hepatitis B. Four patients with a chronic infection were treated with either an IFN-alpha monotherapy or a combination of IFN-alpha and lamivudine. Twenty-nine sera from healthy individuals and non-hepatitis B patients served as negative controls. The assay was validated by using a 10-fold dilution series of the World Virological Quality Control (VQC) sample containing 3.73 x 10(7) genome equivalents per ml. The detection limit for the real-time PCR was 3.73 x 10(2) genome equivalents per ml (geq/ml), while it was 3.73 x 10(3) geq/ml for the in-house PCR. The real-time PCR assay had an 8-logarithm dynamic range spanning from 10(2) to 10(10) geq/ml. In clinical serum samples, the real-time PCR and the in-house PCR detected HBV DNA in 81% (101/125) and 66% (83/125) of samples, respectively. HBV DNA was not detected among the negative controls by either of these assays. In conclusion, real-time PCR is a sensitive, specific, and a reproducible approach for the detection and quantitation of HBV DNA in clinical serum samples, useful also for monitoring the efficacy of antiviral treatment.     

Detection of hepatitis B virus DNA in sera from patients with chronic hepatitis B virus infection by DNA microarray method

We have developed a sensitive and quantitative assay using a DNA microarray for the detection of hepatitis B virus (HBV) DNA in serum. Fluorescently labeled target cDNA prepared from cloned HBV DNA or serum HBV DNA was hybridized to capture DNA on a slide. A linear relationship was obtained between the intensities of the array spot and the amount of the cloned or serum HBV DNA, indicating the quantitative accuracy of this assay system. In addition, there was a significant correlation between the number of molecules of serum HBV DNA determined by the DNA microarray and that determined by a branched-DNA assay (n = 21, r = 0.89). Given these results, we conclude that the DNA microarray assay system may be useful as a diagnostic technique in the clinical laboratory.     

Detection of hepatitis B virus DNA in hepatocellular carcinoma.

DNA-DNA hybridization was used to examine tissue from 31 patients with hepatocellular carcinoma (HCC) in Taiwan for the presence of the hepatitis B virus genome. Twenty-four of the DNA samples had discrete high molecular weight bands when cut with HindIII and hybridized with a radiolabelled HBV DNA probe, and similar results were obtained with 25 of the samples when cut with EcoRI. Thus integrated HBV DNA was present in almost 80% of the specimens. None of the samples had a similar pattern and most contained HBV DNA integrated at multiple sites. Seventeen out of 19 HBsAg carriers and one out of two patients with anti-HBs were found to have integrated HBV DNA in the tumour tissue, providing further evidence of the strong association between HBV infection and development of hepatocellular carcinoma.     

Dual-probe assay for detection of lamivudine-resistance hepatitis B virus by real-time PCR

A rapid and accurate minor groove binder (MGB) real-time PCR is described for detection lamivudine resistance mutations in hepatitis B virus. The real-time PCR was compared with direct Sanger sequencing in 53 clinical patients samples, the results of the real-time PCR correlate with the nucleotide sequence and the assay has the advantage of detecting a mixture of quasi-species with higher sensitivity than sequencing. As a simple, easy, rapid, accurate and high throughout method, MGB real-time PCR assay should be useful for detecting lamivudine resistance variants during lamivudine therapy in clinical settings.     

A genotype-independent real-time PCR assay for quantification of hepatitis B virus DNA

Accurate quantification of hepatitis B virus (HBV) DNA levels is important for monitoring patients with chronic HBV infection and for assessing their responses to antiviral therapy. This study aimed to develop a real-time PCR assay that is sensitive and can accurately quantify a wide range of HBV DNA levels across the known HBV genotypes. An "in-house" real-time PCR assay using primers and a TaqMan probe in a highly conserved region of the HBV surface gene was designed. The assay was standardized against a WHO standard and validated against plasmids of HBV genotypes A through H. The linear quantification range was approximately 5 x 10(0) to 2.0 x 10(9) IU/ml. Results of samples from patients infected with HBV genotypes A through H tested using our real-time "in-house" PCR assay showed an excellent correlation with those of the Cobas Amplicor HBV Monitor (R2=0.9435) and the Cobas TaqMan HBV (R2=0.9873) tests. We have established a real-time PCR assay that is genotype independent and can accurately quantify a wide range of HBV DNA levels. Further studies of additional samples are ongoing to validate the genotype independence of our assay.     

Role of hepatitis B virus genotypes and quantitative HBV DNA in metastasis and recurrence of hepatocellular carcinoma

Identification of risk factors for recurrence and metastasis of HCC is important for the prognosis of HCC surveillance in chronic HBV infection. In this article, 125 HCC patients recruited were followed up prospectively for tumor metastasis and recurrence for a median of 104 (10-130) weeks. HBV DNA level was detected by LightCycler-based real-time fluorescence quantitative polymerase chain reaction-restriction system. HBV genotypes were determined by using PCR restriction-fragment length polymorphism. BCP and PC mutations were performed by PCR and direct sequencing of amplified products. Among 125 HCC patients, 19 patients were excluded because of the lack of follow-up data and the remaining 106 patients were followed up of 2 years and entered into analysis. Sixty-nine patients had tumor metastasis or recurrence during the follow-up and the cumulative probability of HCC metastasis or recurrence was 65.1%. On multivariate analysis, genotype C and HBV DNA level were the risk factors for HCC recurrence or metastasis. The incidence of recurrence or metastasis increased with baseline HBV DNA level in a dose-response relationship ranging from 22% for HBV DNA level of less than 3 log10 copies/ml to 80% for HBV DNA level of 5 log10 copies/ml or greater (P = 0.012). Fifty-seven (74.0%) and 12 (41.4%) patients had metastasis or recurrence in patients with genotype C and B, respectively. The adjusted OR of recurrence or metastasis for genotype C compared with genotype B was 9.755 (P = 0.009). In conclusion, elevated HBV DNA level and genotype C are strong risk predictors of HCC metastasis or recurrence.     

Assessment of the target-capture PCR hepatitis B virus (HBV) DNA quantitative assay and comparison with commercial HBV DNA quantitative assays

Recent clinical studies suggest that hepatitis B virus (HBV) load and genotype may be independent predictors of responses to antiviral therapies. However, it is difficult for clinicians to accurately determine viral loads in patient samples because results--both the values and the units of measure--can vary greatly among different tests. Accordingly, the World Health Organization (WHO) has produced the first international standard for HBV DNA for nucleic acid amplification technology (NAT) assays. In the present study, we describe the performance of the target-capture PCR HBV DNA quantitative assay for the quantitation of HBV DNA in clinical samples and reference panels. The range of quantitation was between 50 and 10(10) IU/ml. The sensitivity and accuracy of the target-capture PCR assay were demonstrated by using the HBV panel from Quality Control for Medical Diagnostics (QCMD) and the WHO HBV DNA standard. The target-capture PCR assay quantitated the six genotype A members of the QCMD panel and dilutions of the WHO HBV DNA standard within an accuracy of 74 to 142%. Compared to current serological methods, the assay offers window period reductions of 19 days prior to HBV surface antigen and 26 days prior to HBV e antigen detection. The target-capture PCR assay was also compared with four commercially available NAT assays, and the various units of measure were standardized with respect to the international units of the WHO HBV DNA standard. The target-capture PCR assay is a sensitive, accurate, high-throughput, rapid, and reproducible assay for the determination of HBV loads.     

慢性肝炎和肝癌病人血清中乙型肝炎病毒DNA的检测

为了了解慢性肝炎和肝癌病人患者体内乙型肝炎病毒（ＨＢＶ）复制与ＨＢＶ血清标志之间的关系，用酶联免疫吸附实验（ＥＬＩＳＡ）、聚合酶链反应（ＰＣＲ）及斑点杂交方法对６１例慢性肝炎和４７例肝癌患者的ＨＢＶ表面抗原（ＨＢｓＡｇ）、相关ｅ抗原（ＨＢｅＡｇ）、表面抗体（抗－ＨＢｓ）、核心抗体（抗－ＨＢｃ）、相关ｅ抗体（抗－ＨＢｅ）进行了检测。结果表明：ＨＢＶＤＮＡ在ＨＢｓＡｇ、ＨＢｅＡｇ、／抗－ＨＢｃ阳性的慢性肝炎和肝癌患者血清中的检出率分别为９０．５０％和５０．００％；在ＨＢｓＡｇ／抗－ＨＢｅ、抗－ＨＢｃ阳性者的检出率分别为４５．４０％和７．１４％；在ＨＢｓＡｇ阳性、ＨＢｅＡｇ阴性／抗－ＨＢｅ阴性者中的检出率分别为６０．００％和４０．００％；ＨＢｓＡｇ阴性、／抗－ＨＢｃ阳性或／抗－ＨＢｅ阳性或／抗－ＨＢｓ阳性者中的检出率分别为２０．００％和２２．２２％；在血清学指标全阴性时，慢性肝炎和肝癌患者血清中ＨＢＶＤＮＡ的检出率均为０。实验提示：无论是肝炎或肝癌，在ＨＢｓＡｇ、ＨＢｅＡｇ同时阳性时，ＨＢＶ复制最为活跃；在单独ＨＢｓＡｇ阳性时，ＨＢＶ有一定程度的复制；ＨＢＶ复制在肝癌细胞中受到一定程度的抑制。     

Real-time PCR assay using molecular beacon for quantitation of hepatitis B virus DNA

Levels of hepatitis B virus (HBV) DNA in the blood serve as an important marker in monitoring the disease progression and treatment efficacy of chronic HBV infection. Several commercial assays are available for accurate measurement of HBV genomic DNA, but many of them are hampered by relatively low sensitivity and limited dynamic range. The aim of this study was to develop a sensitive and accurate assay for measuring HBV genomic DNA using real-time PCR with a molecular beacon (HBV beacon assay). The performance of this assay was validated by testing serial dilutions of the two EUROHEP HBV DNA standards (ad and ay subtypes) of known concentrations. The assay showed low intra-assay (<7%) and interassay (<5%) variations for both subtypes. Its dynamic range was found to be 10(1) to 10(7) copies per reaction (1.0 x 10(2) to 1.0 x 10(9) copies ml(-1)). The assay was further evaluated clinically using serum samples from 175 individuals with chronic hepatitis B. The HBV DNA level measured by this assay showed good correlation with that measured by the commercially available COBAS AMPLICOR HBV Monitor test (r = 0.901; P < 0.001). The higher sensitivity and broader dynamic range of this assay compared to the existing commercial assays will provide an ideal tool for monitoring disease progression and treatment efficacy in HBV-infected patients, in particular for those with low levels of HBV viremia.     

Development of a quantitative real-time detection assay for hepatitis B virus DNA and comparison with two commercial assays

A highly reproducible and sensitive real-time detection assay based on TaqMan technology was developed for the detection of hepatitis B virus (HBV) DNA and compared with two commercially available assays. The assay was validated with the Viral Quality Control panel, which also includes EUROHEP HBV DNA standards. This real-time PCR detection system had a dynamic range of 373 to 10(10) genome copies per ml and showed an excellent correlation with both the commercial HBV Digene Hybrid Capture II microplate assay (Digene Diagnostics) and the HBV MONITOR assay (Roche Diagnostics). To demonstrate its clinical utility, four chronically HBV-infected patients treated with lamuvidine were monitored using the three different assays. From the results we concluded that this assay is an excellent alternative for monitoring of HBV-infected patients in routine diagnostics and clinical practice, enabling the analysis of a large dynamic range of HBV DNA in a single, undiluted sample.     

Persistence of intrahepatic hepatitis B virus DNA integration in patients developing hepatocellular carcinoma after hepatitis B surface antigen seroclearance

Background/AimsThe role of hepatitis B virus (HBV) integration into the host genome in hepatocarcinogenesis following hepatitis B surface antigen (HBsAg) seroclearance remains unknown. Our study aimed to investigate and characterize HBV integration events in chronic hepatitis B (CHB) patients who developed hepatocellular carcinoma (HCC) after HBsAg seroclearance.MethodsUsing probe-based HBV capturing followed by next-generation sequencing technology, HBV integration was examined in 10 samples (seven tumors and three non-tumor tissues) from seven chronic carriers who developed HCC after HBsAg loss. Genomic locations and patterns of HBV integration were investigated.ResultsHBV integration was observed in six patients (85.7%) and eight (80.0%) of 10 tested samples. HBV integration breakpoints were detected in all of the non-tumor (3/3, 100%) and five of the seven (71.4%) tumor samples, with an average number of breakpoints of 4.00 and 2.43, respectively. Despite the lower total number of tumoral integration breakpoints, HBV integration sites in the tumors were more enriched within the genic area. In contrast, non-tumor tissues more often showed intergenic integration. Regarding functions of the affected genes, tumoral genes with HBV integration were mostly associated with carcinogenesis. At enrollment, patients who did not remain under regular HCC surveillance after HBsAg seroclearance had a large HCC, while those on regular surveillance had a small HCC.ConclusionsThe biological functions of HBV integration are almost comparable between HBsAg-positive and HBsAg-serocleared HCCs, with continuing pro-oncogenic effects of HBV integration. Thus, ongoing HCC surveillance and clinical management should continue even after HBsAg seroclearance in patients with CHB.     

Hepatitis B virus antigens in liver resections from patients with hepatocellular carcinoma

A high rate of hepatitis B virus (HBV) antigen carriers among patients with hepatocellular carcinoma (HCC) has been recorded from areas of endemic HBV infections in Africa and Asia, but there are only rare and contradictory data for Europe. 12 specimens of resected liver tissue were immunohistologically investigated for hepatitis B surface antigen (HBsAg) as well as for hepatitis B core antigen (HBcAg). HBsAg was contained in non-tumorous liver tissue in 66 per cent of these cases. In two cases detection of HBcAg in the liver provided evidence to replication of the virus. HBcAg plus HBsAg were present in tumour tissue in one case. All of the HBV antigen carriers did not have chronic hepatitis. On the other hand, all patients with chronic hepatitis had HBV antigens in their liver tissue. HBV antigens were detectable in 7 non-cirrhotic livers, but were contained in only one of two cirrhotic livers. These results are likely to suggest a possible relevance of HBV infection to the aetiology of HCC even in central Europe without customary liver cirrhosis.     

Characterization of a new sensitive PCR assay for quantification of viral DNA isolated from patients with hepatitis B virus infections

Sensitive and accurate quantification of hepatitis B virus (HBV) DNA is necessary for monitoring patients with chronic hepatitis receiving antiviral therapy in order to determine treatment response and to adapt therapy in case of inadequate virologic control. The development of quantitative PCR assays has been crucial in meeting these needs. The objective of this study was to compare the performance of a new real-time PCR assay (Abbott RealTime) for HBV DNA with that of three other commercial assays for the detection of HBV DNA. These were the Versant 3.0 branched-chain DNA assay, the Cobas Amplicor HBV Monitor test, and the Cobas AmpliPrep-Cobas TaqMan hepatitis B virus assay (CAP-CTM). HBV DNA was measured in blood samples taken from two cohorts of patients with chronic hepatitis. HBV DNA levels measured with the Abbott RealTime assay were highly correlated with those measured with the other three tests over their respective dynamic ranges (r, 0.88 to 0.96). The sensitivity (detection limit, 10 IU/ml) and dynamic range of the Abbott RealTime assay (10(1) to 10(9) IU/ml) was superior to that of the Versant assay. The RealTime assay recognized both HBV strains belonging to genotypes A to G and those bearing polymerase gene mutations equivalently. In conclusion, this study demonstrates the utility of the Abbott RealTime assay for monitoring HBV DNA levels in patients with chronic hepatitis B. Its sensitivity and wide dynamic range should allow optimal monitoring of antiviral therapy and timely treatment adaptation.     

Association of hepatitis B virus with chronic liver diseases and hepatocellular carcinoma

The idea of hepatitis-cirrhosis-hepatocellular carcinoma sequence in liver was proposed by the workers in tropical Africa, the homeland of hepatocellular carcinoma. The discovery of Australia antigen by Blumberg et al provided the missing link and it was observed by several workers as well as the present group that Hepatitis B surface antigen (HBSAg) and that to Hepatitis B Virus (HBV) is someway related with the incidence of chronic liver disease and hepatocellular carcinoma (HCC).