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At least 19 recordsLinked to original sources
PubMed2026

Genomic and transcriptomic features of HBV integration in treatment-naïve, HBeAg-positive children with chronic HBV infection.

BACKGROUND: Hepatitis B virus (HBV) integration represents a major obstacle to curing HBV; however, the landscape of HBV integration and local immune response to transcriptionally active viral integration in children with chronic HBV infection remain unclear. Herein, we aimed to elucidate this landscape in this population. METHODS: Genomic analyses using a probe-based capture strategy were performed on 18 children and 28 adults with chronic HBV infection. Spatial transcriptomics (ST) was performed on 12 children from our cohort and 3 adults from a public database. FINDINGS: All patients were hepatitis B e antigen (HBeAg)-positive and treatment-naïve. Genomically, children exhibited significantly lower clonal expansion level of HBV-integrated hepatocytes than adults, despite comparable unique breakpoint counts. After adjusting for confounding variables, age was identified as an independent risk factor for total frequency of unique integration breakpoints (b = 3.22, P = 0.005). Spatially, ST revealed that spots with transcriptionally active viral integration exhibited a sparse distribution and accounted for a low proportion of all spots in children. Notably, at these spots, children showed reduced adaptive immune cells (e.g., CD8+ T cells) but increased innate components (myeloid cells, Kupffer cells, activated dendritic cells) and APC co-stimulation, whereas adults exhibited a uniform reduction of immune cell populations. INTERPRETATION: Compared with adults, children exhibit lower clonal expansion of HBV-integrated hepatocytes and distinct immune profiles in response to transcriptionally active viral integration, offering new insights into their differing clinical course. FUNDING: Key Laboratory of Molecular Biology for Infectious Diseases (Ministry of Education).

Humans↗
PubMed2026

Sex Hormone Receptors, HBV Integrations and Their Prognostic Predictive Value Among Hepatocellular Carcinoma Patients.

Hepatocellular carcinoma (HCC) related to hepatitis B virus (HBV) infection predominantly affects males, yet few studies have investigated the association between sex hormones and HBV integrations, and their involvement in HCC prognosis. We assessed estrogen receptor alpha (ERα) and androgen receptor (AR) expression via immunohistochemistry on tissue microarrays constructed from 426 HBV-related HCC samples. HBV integration features were determined using HBV-captured sequencing data. Logistic regression models were utilized to evaluate the association between sex hormone receptor expression level and HBV integration features. Cox regression models, combined with machine learning (ML) methods, were implemented to investigate the prognostic value of sex hormone receptors and HBV integrations concerning overall survival. We found high AR expression level was significantly associated with higher HBV integration levels (adjusted odds ratio [aOR] = 1.84, 95% confidence interval [CI]: 1.09-3.11, P for trend = 0.012), TERT integration (aOR = 2.34, 95% CI: 1.16-4.74, P for trend = 0.047), intergenic integration (aOR = 2.25, 95% CI: 1.20-4.24, P for trend = 0.021), and promoter integration (aOR = 1.81, 95% CI: 1.00-3.31, P for trend = 0.034). The inclusion of sex hormone receptors and HBV integrations in the predictive models led to improvements across all performance metrics in the Cox regression analyses (AUC improvement: 0.014 [Training], 0.026 [Validation]) and the ML (AUC improvement: 0.022 [Training]), although a slight deterioration in performance was noted in the ML validation set. The results suggested a relationship between AR expression level and HBV integration events, as well as the potential utility of HBV integration biomarkers and sex hormone receptor profiles in assessing post-surgical prognosis among HCC patients.

Humans↗
PubMed1989

Features of two hepatitis B virus (HBV) DNA integrations suggest mechanisms of HBV integration.

Two integrated hepatitis B virus (HBV) DNA molecules were cloned from two primary hepatocellular carcinomas each containing only a single integration. One integration (C3) contained a single linear segment of HBV DNA, and the other integration (C4) contained a large inverted duplication of viral DNA at the site of a chromosome translocation (O. Hino, T.B. Shows, and C.E. Rogler, Proc. Natl. Acad. Sci. USA 83:8338-8342, 1986). Sequence analysis of the virus-cell junctions of C3 placed the left virus-cell junction at nucleotide 1824, which is at the 5' end of the directly repeated DR1 sequence and is 6 base pairs from the 3' end of the long (L) negative strand. The right virus-cell junction was at nucleotide 1762 in a region of viral DNA (within the cohesive overlap) which shared 5-base-pair homology with cellular DNA. Sequence analysis of the normal cellular DNA across the integration site showed that 11 base pairs of cellular DNA were deleted at the site of integration. On the basis of this analysis, we suggest a mechanism for integration of the viral DNA molecule which involves strand invasion of the 3' end of the L negative strand of an open circular or linear HBV DNA molecule (at the DR1 sequence) and base pairing of the opposite end of the molecule with cellular DNA, accompanied by the deletion of 11 base pairs of cellular DNA during the double recombination event. Sequencing across the inverted duplication of HBV DNA in clone C4 located one side of the inversion at nucleotide 1820, which is 2 base pairs from the 3' end of the L negative strand. Both this sequence and the left virus-cell junction of C3 are within the 9-nucleotide terminally redundant region of the HBV L negative strand DNA. We suggest that the terminal redundancy is a preferred topoisomerase I nicking region because of both its base sequence and forked structure. Such nicking would lead to integration and rearrangement of HBV molecules within the terminal redundancy, as we have observed in both our clones.

Base Sequence↗
PubMed1990

Different type of hepatitis B virus (HBV) DNA integrants that may reflect the integration process.

Through analyses of HBV DNA integratns in human cellular DNA, we identified three different integrant types, each of which may reflect the process of primary integrant formation by the viral DNA. The first type, which we call "simple type" consists of integrants found in some hepatocellular carcinomas (HCC's). The structure of the viral genome is simple, and part of it is deleted. The viral cohesive end sequence appears at one of the viral-cellular DNA junctions, and integration has elicited a microdeletion in the target cellular DNA sequence. This structure suggests viral DNA replication intermediates as substrates for integration. Judging from its frequency in HCC, this type may represent the most preferred one, if not all, among the primary integration products. The second type, which we call "complex type" is essentially the same as the first type, except tht the viral genome structure is complex. We considered the possibility that they may have been produced via the same process, using preformed complex viral genomes such as "novel form DNA's" (Rogler and Summers, 1982) as substrates. In cultured fetal hepatocytes, integration of HBV DNA can occur only a few days after infection. Among such integrants, we found a third type integrant, having a simple viral genome, but having a larger cellular DNA deletion. We propose that different forms of viral DNA may be used as substrates in the integration process, and the process is characterized by its eliciting of deletions of different size in the target cellular DNA. The most preferred substrate may be the one producing the simple type integrants, and the most frequently occurring deletion in the target DNA may be the microdeletion.(ABSTRACT TRUNCATED AT 250 WORDS)

Base Sequence↗
PubMed1992

Enhancement of hepatitis-B surface-antigen expression by 5-azacytidine in a hepatitis-B-virus-transfected cell line.

The human hepatoblastoma-derived cell line HB611 secretes hepatitis-B surface antigen (HBsAg) and hepatitis-B e antigen (HBeAg) into the medium. Hepatitis-B-virus (HBV) DNA integrated into the cellular genome was found to be hypermethylated. When the cells were treated with 5-azacytidine for 3 days, the level of HBsAg in the medium increased, while the level of HBeAg remained constant. The level of alpha-fetoprotein (AFP) decreased with the 5-azacytidine treatment. Southern blot analysis of DNA digested with HpaII or MspI showed that 5-azacytidine treatment resulted in hypomethylation of the integrated HBV DNA, suggesting that 5-azacytidine increased HBsAg production in the cells through hypomethylation of the HBV genomic DNA.

Azacitidine↗
PubMed1991

Chromosomal sites for hepatitis B virus integration in human hepatocellular carcinoma.

The discovery that hepatitis B virus (HBV) integrates into host chromosomes raises the question of whether such viral DNA integration correlates directly with the activation of specific oncogenes or the inactivation of anti-oncogenes. To obtain insight into this problem, we randomly collected HBV integrant samples from different human hepatocellular carcinomas and identified the site of chromosomal integration by using in situ hybridization and/or linkage analysis with the flanking cellular DNAs as probes. Our findings did not specifically identify particular HBV DNA integration sites in chromosomes, although chromosomes 11 and 17 seemed to have more than the average number of integrants.

Alleles↗
PubMed1990

Integrated structures of HBV DNA in chronic hepatitis and hepatoma tissues.

Cellular DNAs of chronically hepatitis B virus (HBV)-infected human livers were analysed by Southern blot hybridization for the presence of integrated HBV DNA. In 15 out of 16 tissue samples, random HBV DNA integration was evident. By molecular cloning and structural analyses of 19 integrants from 3 chronic hepatitis tissues, rearrangement of HBV DNA with inverted duplication or translocation of cellular flanking DNA at the virus-cell junction was noted. Thus, the rearrangement of HBV DNA or cellular flanking DNA not to be a specific incident of HCC formation. Analyses of various integrants bearing HBV DNA rearrangement and their cellular counterpart DNAs failed to indicate any gross structural alteration in cellular DNA except for a small deletion at the integration sites, indicating HBV DNA rearrangement with inverted duplication to possibly occur prior to integration. Based on nucleotide sequencing analyses of virus-virus junctions, a mechanism of this inverted duplication of HBV DNA is proposed, in which an illegitimate recombination may take place by means of a patchy homology on one side of adjoining viral sequences.

Base Sequence↗
PubMed1991

Chromosome deletions associated with hepatitis B virus integration.

Integrated hepatitis B virus (HBV) DNA is often found in hepatocellular carcinomas which develop in HBV carriers. We previously found that chromosomal abnormalities such as translocations and inversions are often associated with HBV integration. Here we report deletions that were found with three integrants, by comparing the physical maps of the flanking cellular DNA of the integrants with those of the unoccupied cellular sequences. The sizes of the deletions were 25, 12, and 11 kb, respectively. Each integrant carried only a small fragment of the viral genome, from which the cohesive end region, the preferred site of integration, was deleted. We speculate that these deletions were made from primary integrants by recombination of regions between the viral DNA and the flanking cellular sequence.

Base Sequence↗
PubMed1992

Hepatitis B virus replication in well differentiated mouse hepatocyte cell lines immortalized by plasmid DNA.

The primary hepatocytes cultured from adult BALB/c mice were readily transfected by plasmid DNA and could be immortalized at a frequency of approximately 0.1 to 0.6 x 10(-7) cells/micrograms of the transfected DNA. There was no detectable plasmid DNA at the tenth cell passages. A total of five mouse hepatocyte cell lines were established. Most of them were tumorigenic. Three of the established mouse hepatocyte cell lines were well differentiated, since they expressed liver-specific genes. Further transfection of these three well differentiated mouse hepatocyte cell lines with hepatitis B virus (HBV) DNA showed that the HBV-transfected cells had integrated HBV genomes, HBV-specific mRNA transcripts, and expression of hepatitis B surface and hepatitis B core antigens. One of the lines, ML-3Neo (HBV), even secreted HBV-like particles. Furthermore, circulating hepatitis B surface antigens were detected in the sera of BALB/c mice bearing ML-3Neo (HBV) tumors. These cell lines provide a convenient model for future studies on the host immune reaction against HBV and on the transformation of hepatocytes by HBV and other cellular oncogenes and the determination of their effects on hepatocellular differentiation.

Animals↗
PubMed1990

Hepatitis B virus as an insertional mutagene in a human hepatocellular carcinoma.

Chronic hepatitis B virus (HBV) infection is etiologically related to human hepatocellular carcinoma (HCC). Most HCCs contain integrated HBV DNA in the liver cellular DNA, suggesting that the integration may be involved in carcinogenesis. From a comparison of a single HBV integration site present in a hepatoma with the corresponding unoccupied site in the non-tumourous tissue of the same liver, we have shown that HBV DNA inserted in a putative cellular exon with striking similarity to the DNA-binding domain of the thyroid/steroid hormone receptors. The corresponding cDNA has been isolated (hap gene) and shown to encode the retinoic acid receptor. In the original patient, integration took place so that the first codons of the viral surface protein gene became fused in frame with most of the hap gene. Because retinoic acid is known to regulate the transcription of target genes crucial for cellular growth and differentiation, it is most probable that consequent to the HBV insertion, hap, usually transcribed at a very low level in normal hepatocytes, became inappropriately expressed as an altered chimaeric retinoic acid receptor, thus contributing to the cell transformation. These results strongly support the possibility that HBV may play a direct role in liver carcinogenesis by insertional mutagenesis.

Amino Acid Sequence↗
PubMed2026

Triple primary synchronous liver cancer in one patient: the first case report and origin speculation through bioinformatics.

INTRODUCTION: A diagnosis of multiple primary liver tumors is extremely rare. Preoperative diagnosis based on imaging findings is difficult. Moreover, the clinical benefits of treatment strategies for multiple liver cancers remain unclear. Here, we report a case of three synchronous primary liver tumors with three distinct pathological types-hepatocellular carcinoma (HCC), intrahepatic cholangiocarcinoma (ICC), and combined hepatocellular-cholangiocarcinoma (cHCC‑CCA)-in a single patient. Bioinformatics analysis supported at least two clonal origins, with cHCC‑CCA and ICC sharing a common lineage based on identical HBV integration sites. CASE PRESENTATION: A 63-year-old female with a history of hepatitis B for several years presented with three lesions in hepatic segment VIII. Multiphase magnetic resonance imaging with gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid revealed a diagnosis of multiple lesions, namely, cHCC‑CCA, with multiple intrahepatic metastases. The AFP level was normal, while the CA 19 - 9 level was mildly elevated (normal range ≤ 30.00 U/ml). Hepatectomy was performed, and postoperative assessment confirmed that the large lesion was cHCC‑CCA. However, the small lesions close to the large lesion were HCC and ICC. Gene testing revealed distinct mutational profiles among the three tumors. Similar gene mutations were detected in cHCC‑CCA and ICC. We also found that gene fragments of hepatitis B virus-C (HBV-C) were inserted into the genomes of ICC and cHCC‑CCA rather than that of HCC. The genomic integration site of HBV-C in cHCC‑CCA and ICC was the same. CONCLUSION: We report an extremely rare case of three synchronous primary liver tumors with three distinct pathological types (HCC, ICC, and cHCC‑CCA) in a single patient. Bioinformatics analysis supported at least two clonal origins, with cHCC‑CCA and ICC sharing a common lineage based on identical HBV integration sites. Hepatectomy represents a potential radical strategy for the treatment of multiple PLCs.

Humans↗
PubMed1990

Antisense oligodeoxyribonucleotides inhibit the expression of the gene for hepatitis B virus surface antigen.

The effect of a series of antisense oligodeoxyribonucleotide [oligo(dN)] on the expression of the surface antigen (HBsAg) gene of human hepatitis B virus (HBV) was examined using hepatocellular carcinoma cells that contain integrated HBV genomes. Of a number of antisense oligo(dN)s tested, synthetic 15-mers directed at the cap site of mRNA and regions of the translational initiation site of the HBsAg gene were found to be highly effective and inhibited viral gene expression by as much as 96%. The inhibition was specific to the HBsAg gene and appeared to be at the level of translation. These results suggest a therapeutic potential for antisense oligo(dN) in the treatment of patients who are chronically infected with HBV.

Base Sequence↗
PubMed1990

Persistence of hepatitis B virus DNA after serological clearance of hepatitis B virus.

Using Southern blot technique, the state of hepatitis B virus (HBV) DNA in liver tissue was investigated in 16 patients who were sero-negative for hepatitis B surface antigen (HBsAg) but positive for its antibody (anti-HBs). In only one case, was HBV DNA found in liver tissue in a heterogeneously integrated form. In this case, digestion with Taq I demonstrated integrated HBV DNA as two definite bands at 1.8 and 0.5 kbp. This suggests that HBV DNA in some cases persists even after HBV infection has been cleared serologically. It is possible that this persistence of HBV DNA plays an important role in hepatocarcinogenesis.

DNA Probes↗
PubMed1989

[Molecular aspects of human hepatocellular carcinoma].

It is now evident that development of hepatocellular carcinoma (HCC) in human is associated with a long series of cellular and tissue changes that precede the ultimate development of the cancer. During recent years, enormous progress in molecular research on HCC has been made, particularly in the area of integration of HBV DNA to host cell and oncogene association with carcinogenicity. A high ratio of HCCs from patients in endemic area has integrated HBV DNA in cellular DNA and in some cases, chromosomal translocations associated with HBV integration were observed, suggesting that the integration or the results thereof are connected with cancer development. Employing a DNA-mediated transfection assay using NIH3T3 mouse fibroblasts with high molecular weight DNA, we detected three cellular transforming genes (lca, N-ras, hst) in primary human HCC. However, little is known as to the linkage between the activation of these genes and liver carcinogenesis. In most human primary HCC tissues, at least two oncogenes, c-myc and N-ras are overexpressed, while in some cases other oncogenes c-fos or lca are overexpressed. It is likely that multiple c-oncogens are important in HCC, but specific transcripts for the malignancy of HCC were not detected. At present, we could not find any relationship between the expression of c-oncogenes and integration of HBV, serological markers or the degree of differentiation. Of the experimental animals most frequently used for studies of liver cancer, the rat is best understood and mimics closely many of the lesions in humans. It is of interest to consider that the identification and elucidation of the mechanisms underlying carcinogenic processes in the rat may offer testable hypotheses for steps in the human.

Adult↗
PubMed1990

Replication of hepatitis B virus in transfected nonhepatic cells.

Permanent murine fibroblasts (LTK-) were transfected with a dimer of hepatitis B virus (HBV) DNA and a neomycin resistance gene which were both linked to the simian virus 40 (SV40) early promoter/enhancer. One of the stably transfected clones, LTK4/36, which secreted HBsAg, HBeAg, and HBV DNA was further analyzed. It contained eight to nine copies of integrated HBV DNA per haploid genome and low amounts of episomal HBV DNA. The secreted viral DNA was covalently linked to protein and was associated with particles which had the characteristic density of natural virions from serum of human viremic carriers. The particles contained an endogenous DNA polymerase, small and middle surface proteins, but in contrast to natural virions very little core protein and large surface protein. Instead of core protein, they contained incompletely processed HBe protein which is colinear to core protein. The fibroblast-derived virions were less stable than virions from human carriers or from transfected hepatoma cells. After several days of storage, their DNA was only partially protected against DNase. Obviously, nonhepatic cells can express HBV-like particles, even if liver-dependent gene products like large surface protein and core protein are missing.

Animals↗
PubMed1992

[Significance of detailed Hepatitis B virus marker studies in chronic liver diseases].

The hepatitis B virus (HBV) markers were studied by Sorin RIA kits in the sera of 390 patients suffered from histologically confirmed chronic liver disease. On the base of HBsAg, anti-HBs, anti-HBc seronegativity the HBV infection was excluded in 235 cases. In most HBV negative cases the diagnosis was fatty liver and alcoholic hepatitis (52%), while chronic active hepatitis and/or liver cirrhosis occurred only in 21.7% of patients. Past or present HBV infection was proved in 155 patients. The diagnosis of 52.9% of cases in this group was chronic active hepatitis and/or liver cirrhosis, while fatty liver and alcoholic hepatitis occurred in 27.7%. The detailed HBV marker analysis was performed in 76 patients. Previous infection without replication (anti-HBs and/or anti-HBc and/or anti-HBe positivity) was proved in 48 cases, 12 patients have active HBV infection (HBsAg, HBe, IgM anti--HBc, positivity), while in 16 cases integrated HBV infection (HBsAg, anti-HBc, anti-HBe positivity) was proved. The HBsAg--IgM complex seropositivity was detected in every case with active HBV replication. Because of therapeutic, prognostic and epidemiologic significances the detailed HBV serology in chronic liver diseases is stressed.

Adolescent↗
PubMed1991

Hepatitis B x antigen in hepatitis B virus carrier patients with liver cancer.

Formalin-fixed, paraffin-embedded specimens from 110 cases of primary hepatocellular carcinoma were stained for hepatitis B x antigen (HBxAg), hepatitis B surface antigen (HBsAg), and hepatitis B core antigen (HBcAg). Eighty-four % of these patients were HBxAg positive in their tumor cells. Among the 110 cases studied, 80 had adjacent nontumorous tissue in the same block, and 65 of these nontumorous liver tissues stained positive for HBxAg (81%). HBsAg was positive in 19% of cases within tumor tissue and 61% in surrounding nontumorous tissue. HBcAg was positive in 11% of cases within tumor tissue and 26% in surrounding nontumorous tissue. These findings show that HBxAg is a common marker in the liver of patients with hepatitis B virus (HBV)-associated primary hepatocellular carcinoma and that it is closely associated with tumor cells in these individuals. In addition, the finding of HBxAg in the absence of detectable HBsAg and HBcAg in the liver tissues of many HBsAg carriers suggests that HBxAg could be expressed independent of HBV replication and implies that the synthesis of this antigen may be directed from integrated HBV DNA templates. The finding of HBxAg in the nucleus of hepatocytes from primary hepatocellular carcinoma patients with dysplasia, combined with the known trans-activating properties of HBxAg, implies that HBxAg plays one or more important roles in hepatocarcinogenesis. The finding of HBxAg in bile duct epithelium and cholangiocarcinoma tissues is compatible with the hypothesis that HBV may contribute to this other primary tumor type in the liver. Together, these results further implicate HBxAg in the pathogenesis of primary liver cancers.

Carcinoma, Hepatocellular↗