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Background: SARS-CoV-2 began spreading in December 2019 and has since become a pandemic that has impacted many aspects of human society. Several issues concerning the origin, time of introduction to humans, evolutionary patterns, and underlying force driving the SARS-CoV-2 outbreak remain unclear. Method: Genetic variation in 137 SARS-CoV-2 genomes and related coronaviruses as of 2/23/2020 was analyzed. Result: After correcting for mutational bias, the excess of low frequency mutations on both synonymous and nonsynonymous sites was revealed which is consistent with the recent outbreak of the virus. In contrast to adaptive evolution previously reported for SARS-CoV during its brief epidemic in 2003, our analysis of SARS-CoV-2 genomes shows signs of relaxation. The sequence similarity in the spike receptor binding domain between SARS-CoV-2 and a sequence from pangolin is probably due to an ancient intergenomic introgression that occurred approximately 40 years ago. The current outbreak of SARS-CoV-2 was estimated to have originated on 12/11/2019 (95% HPD 11/13/2019–12/23/2019). The effective population size of the virus showed an approximately 20-fold increase from the onset of the outbreak to the lockdown of Wuhan (1/23/2020) and ceased to increase afterwards, demonstrating the effectiveness of social distancing in preventing its spread. Two mutations, 84S in orf8 protein and 251 V in orf3 protein, occurred coincidentally with human intervention. The former first appeared on 1/5/2020 and plateaued around 1/23/2020. The latter rapidly increased in frequency after 1/23/2020. Thus, the roles of these mutations on infectivity need to be elucidated. Genetic diversity of SARS-CoV-2 collected from China is two times higher than those derived from the rest of the world. A network analysis found that haplotypes collected from Wuhan were interior and had more mutational connections, both of which are consistent with the observation that the SARS-CoV-2 outbreak originated in China. Conclusion: SARS-CoV-2 might have cryptically circulated within humans for years before being discovered. Data from the early outbreak and hospital archives are needed to trace its evolutionary path and determine the critical steps required for effective spreading. [ABSTRACT FROM AUTHOR]

The telomerase-specific oncolytic adenovirus Telomelysin and the histone deacetylase inhibitor AR42 have demonstrated anticancer effects in preclinical models of human hepatocellular carcinoma (HCC). However, the clinical development of Telomelysin may be hindered by human antiviral immunity and tumor resistance. Combining oncolytic and epigenetic therapies is a viable approach for treating various cancers. This study investigated the potential synergism of Telomelysin and AR42 and the relevant underlying mechanisms. Telomelysin and AR42 exhibited synergistic antiproliferative effects in human HCC models in vitro and in vivo. Apoptosis induced by Telomelysin was significantly enhanced by AR42 in both PLC5 and Hep3B HCC cells. AR42 treatment unexpectedly attenuated the expression of the coxsackievirus and adenovirus receptor and the mRNA levels of human telomerase reverse transcriptase, which may be positively associated with the cytotoxicity of Telomelysin. Meanwhile, the cellular antiviral interferon response was not altered by AR42 treatment. Further, we found that Telomelysin enhanced Akt phosphorylation in HCC cells. AR42 reduced Telomelysin-induced phospho-Akt activation and enhanced Telomelysin-induced apoptosis. The correlation of Akt phosphorylation with drug-induced apoptosis was validated in HCC cells with upregulated or downregulated Akt signaling. Combination therapy with Telomelysin and AR42 demonstrated synergistic anti-HCC efficacy. Clinical trials investigating this new combination regimen are warranted. • Tumor resistance and human antiviral immunity impede oncolytic adenovirus development. • Telomelysin and AR42 had demonstrated anticancer effects in preclinical HCC models respectively. • Telomelysin plus AR42 exhibited synergistic efficacy in human HCC models. • Akt signaling contributes crucially to these synergistic effects. • This adenovirus-based combination therapy for human HCC warrants clinical validation. [ABSTRACT FROM AUTHOR]

Background: In regions with a high prevalence of chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infections, coinfected patients face a heightened risk of developing hepatocellular carcinoma (HCC), termed HBV/HCV-related HCC (HBCV-HCC). We aimed to investigate the contribution of preexisting chronic hepatitis B (CHB) and subsequent chronic hepatitis C (CHC) to the development of HBCV-HCC., Methods: We examined HBV's involvement in 93 HBCV-HCC cases by analyzing HBV DNA integration as an indicator of HCC originating from HBV-infected hepatocytes, compared with 164 HBV-HCCs and 56 HCV-HCCs as controls., Results: Next generation sequencing revealed that 55% of HBCV-HCCs exhibited clonal HBV integration, which falls between the rates observed in HBV-HCCs (88%) and HCV-HCCs (7%), with similar integration patterns to HBV-HCCs. Common HCC somatic mutation analysis indicated HCV superinfection in HBCV-HCCs correlated with increased mutation rates in the telomerase reverse transcriptase (TERT) promoter and beta-catenin genes. Transcriptome analysis showed a prevalence of replicating HCV over HBV in HBCV-HCCs, with preexisting HBV exerting a proliferative role. The comparison of clinical characteristics revealed similarities between HBCV-HCC and HCV-HCC patients, including later onset for HBCV-HCC, possibly due to HCV superinfection slowing carcinogenesis. Notably, HBCV-HCCs with the same driver mutation, HBV integration at the TERT promoter, tended to develop later and showed a better prognosis post-tumor resection than HBV-HCCs., Conclusions: Our findings shed light on the interplay between preexisting CHB and subsequent CHC in elevating the risk of HBCV-HCC. These insights are crucial for understanding viral etiology-specific carcinogenesis and guiding surveillance policies for HBCV-HCC post-antiviral therapy., Competing Interests: Declarations. Ethics approval and consent to participate: The clinical samples and data were collected according to the protocol approved by the National Taiwan University Hospital Research Ethics Committee (201701026RINA) with written informed consent. Consent for publication: Not applicable. Competing interests: PJC is the consultant and received a grant from TCM Biotech. STT and YCW are TCM Biotech employees. YT received research funding from AbbVie, Gilead Sciences, Sysmex, Janssen, GlaxoSmithKline and FUJIREBIO. YT received lecture fee from Gilead Sciences, GlaxoSmithKline and HU frontier. YYL, YCW, and STT are the inventors for the probe design used in the current study., (© 2025. The Author(s).)

Background: Studies have shown that hepatitis B virus (HBV)-associated B-cell non-Hodgkin lymphoma (NHL) constitutes a unique subgroup with distinct clinical features. It still leaves open the question of whether the integration of HBV DNA into the B-cell genome is a causal mechanism in the development of lymphoma., Methods: Using the hybridisation capture-based next generation sequencing and RNA sequencing, we characterised the HBV integration pattern in 45 HBV-associated B-cell NHL tumour tissues., Results: A total of 354 HBV integration sites were identified in 13 (28.9%) samples, indicating the relatively low integration frequency in B-cell NHLs. High plasma HBV DNA loads were not associated with the existence of HBV integration. The insertion sites distributed randomly across all the lymphoma genome without any preferential hotspot neither at the chromosomal level nor at the genetic level. Intriguingly, most HBV integrations were nonclonal in B-cell NHLs, implying that they did not confer a survival advantage. Analysis of the paired diagnosis-relapse samples showed the unstable status of HBV integrations during disease progression. Furthermore, transcriptomic analysis revealed the limited biological impact of HBV integration., Conclusion: Our study provides an unbiased HBV integration map in B-cell NHLs, revealing the insignificant role of HBV DNA integration in B-cell lymphomagenesis., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

The proto-oncogene MYCN expression marked a cancer stem-like cell population in hepatocellular carcinoma (HCC) and served as a therapeutic target of acyclic retinoid (ACR), an orally administered vitamin A derivative that has demonstrated promising efficacy and safety in reducing HCC recurrence. This study investigated the role of MYCN as a predictive biomarker for therapeutic response to ACR and prognosis of HCC. MYCN gene expression in HCC was analyzed in the Cancer Genome Atlas and a Taiwanese cohort (N = 118). Serum MYCN protein levels were assessed in healthy controls (N = 15), patients with HCC (N = 116), pre- and post-surgical patients with HCC (N = 20), and a subset of patients from a phase 3 clinical trial of ACR (N = 68, NCT01640808). The results showed increased MYCN gene expression in HCC tumors, which positively correlated with HCC recurrence in non-cirrhotic or single-tumor patients. Serum MYCN protein levels were higher in patients with HCC, decreased after surgical resection of HCC, and were associated with liver functional reserve and fibrosis markers, as well as long-term HCC prognosis (>4 years). Subgroup analysis of a phase 3 clinical trial of ACR identified serum MYCN as the risk factor most strongly associated with HCC recurrence. Patients with HCC with higher serum MYCN levels after a 4-week treatment of ACR exhibited a significantly higher risk of recurrence (hazard ratio 3.27; p = .022). In conclusion, serum MYCN holds promise for biomarker-based precision medicine for the prevention of HCC, long-term prognosis of early-stage HCC, and identification of high-response subgroups for ACR-based treatment., (© 2024 The Authors. International Journal of Cancer published by John Wiley & Sons Ltd on behalf of UICC.)

Background & Aims: HBV expresses more than 10 spliced RNAs from the viral pregenomic RNA, but their functions remain elusive and controversial. To address the function of HBV spliced RNAs, we generated splicing-deficient HBV mutants and conducted experiments to assess the impact of these mutants on HBV infection., Methods: HepG2-NTCP cells, human hepatocyte chimeric FRG mice (hu-FRG mice), and serum from patients with chronic hepatitis B were used for experiments on HBV infection. Additionally, SHifter assays and cryo-electron microscopy were performed., Results: We found the infectivity of splicing-deficient HBV was decreased 100-1,000-fold compared with that of wild-type HBV in hu-FRG mice. Another mutant, A487C, which loses the most abundant spliced RNA (SP1), also exhibits severely impaired infectivity. SP1 hypothetically encodes a novel protein HBc SP1 (HBc -Cys ) that lacks the C-terminal cysteine from full-length HBc. In the SHifter assay, HBc SP1 was detected in wild-type viral particles at a ratio of about 20-100% vs. conventional HBc, as well as in the serum of patients with chronic hepatitis B, but not in A487C particles. When infection was conducted with a shorter incubation time of 4-8 h at lower PEG concentrations in HepG2-NTCP cells, the entry of the A487C mutant was significantly slower. SP1 cDNA complementation of the A487C mutant succeeded in rescuing its infectivity in hu-FRG mice and HepG2-NTCP cells. Moreover, cryo-electron microscopy revealed a disulfide bond between HBc cysteine 183 and 48 in the HBc intradimer of the A487C capsid, leading to a locked conformation that disfavored viral entry in contrast to the wild-type capsid., Conclusions: Prior studies unveiled the potential integration of the HBc -Cys protein into the HBV capsid. We confirmed the proposal and validated its identity and function during infection., Impact and Implications: HBV SP1 RNA encodes a novel HBc protein (HBc SP1 ) that lacks the C-terminal cysteine from conventional HBc (HBc -Cys ). HBc SP1 was detected in cell culture-derived HBV and confirmed in patients with chronic infection by both immunological and chemical modification assays at 10-50% of capsid. The splicing-deficient mutant HBV (A487C) impaired infectivity in human hepatocyte chimeric mice and viral entry in the HepG2-NTCP cell line. Furthermore, these deficiencies of the splicing-deficient mutant could be rescued by complementation with the SP1-encoded protein HBc SP1 . We confirmed and validated the identity and function of HBc SP1 during infection, building on the current model of HBV particles., (Copyright © 2024 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.)

Since its discovery in 1965, our understanding of the hepatitis B virus (HBV) replication cycle and host immune responses has increased markedly. In contrast, our knowledge of the molecular biology of hepatitis delta virus (HDV), which is associated with more severe liver disease, is less well understood. Despite the progress made, critical gaps remain in our knowledge of HBV and HDV replication and the mechanisms underlying viral persistence and evasion of host immunity. The International HBV Meeting is the leading annual scientific meeting for presenting the latest advances in HBV and HDV molecular virology, immunology, and epidemiology. In 2023, the annual scientific meeting was held in Kobe, Japan and this review summarises some of the advances presented at the Meeting and lists gaps in our knowledge that may facilitate the development of new therapies.

Introduction: A set of genetic mutations to classify hepatocellular carcinoma (HCC) useful to clinical studies is an unmet need. Hepatitis B virus-related HCC (HBV-HCC) harbors a unique genetic mutation, namely, the HBV integration, among other somatic endogenous gene mutations. We explored a combination of HBV DNA integrations and common somatic mutations to classify HBV-HCC by using a capture-sequencing platform., Methods: A total of 153 HBV-HCCs after surgical resection were subjected to capture sequencing to identify HBV integrations and three common somatic mutations in genomes. Three mutually exclusive mutations, HBV DNA integration into the TERT promoter, HBV DNA integration into MLL4, or TERT promoter point mutation, were identified in HBV-HCC., Results: They were used to classify HBV-HCCs into four groups: G1 with HBV-TERT integration (25.5%); G2 with HBV-MLL4 integration (10.5%); G3 with TERT promoter mutation (30.1%); and G4 without these three mutations (34.0%). Clinically, G3 has the highest male-to-female ratio, cirrhosis rate, and associated with higher early recurrence and mortality after resection, but G4 has the best outcome. Transcriptomic analysis revealed a grouping different from the published ones and G2 with an active immune profile related to immune checkpoint inhibitor response. Analysis of integrated HBV DNA provided clues for HBV genotype and variants in carcinogenesis of different HCC subgroup. This new classification was also validated in another independent cohort., Conclusion: A simple and robust genetic classification was developed to aid in understanding HBV-HCC and in harmonizing clinical studies., Competing Interests: P.J.C. is the consultant and received a grant from TCM Biotech. S.T.T., C.F.H., and Y.C.W. are employees of TCM Biotech., (© 2023 The Author(s). Published by S. Karger AG, Basel.)

Hepatitis B virus (HBV) DNA integration is an incidental event in the virus replication cycle and occurs in less than 1% of infected hepatocytes during viral infection. However, HBV DNA is present in the genome of approximately 90% of HBV-related HCCs and is the most common somatic mutation. Whole genome sequencing of liver tissues from chronic hepatitis B patients showed integration occurring at random positions in human chromosomes; however, in the genomes of HBV-related HCC patients, there are integration hotspots. Both the enrichment of the HBV-integration proportion in HCC and the emergence of integration hotspots suggested a strong positive selection of HBV-integrated hepatocytes to progress to HCC. The activation of HBV integration hotspot genes, such as telomerase (TERT) or histone methyltransferase (MLL4/KMT2B), resembles insertional mutagenesis by oncogenic animal retroviruses. These candidate oncogenic genes might shed new light on HBV-related HCC biology and become targets for new cancer therapies. Finally, the HBV integrations in individual HCC contain unique sequences at the junctions, such as virus-host chimera DNA (vh-DNA) presumably being a signature molecule for individual HCC. HBV integration may thus provide a new cell-free tumor DNA biomarker to monitor residual HCC after curative therapies or to track the development of de novo HCC., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Although the impact of hepatic androgen receptor (AR) pathway on liver pathogenesis was documented, its physiological function in normal liver is remained unclear. This study aims to investigate if hepatic AR acts on metabolism, the major liver function, using a hepatic-specific AR-transgenic (H-ARTG) mouse model., Methods: We established the albumin promoter driven H-ARTG mice and included wild type (WT) and H-ARKO mice for study. The body weight, specific metabolic parameters and results from various tolerance tests were compared in different groups of mice fed a chow diet, from 2 to 18 months of age. Glucose feeding and insulin treatment were used to study the expression and zonal distribution pattern of AR and related genes in liver at different prandial stages., Results: The body weight of H-ARTG mice fed a chow diet was 15 % lower than that of wild-type mice, preceded by lower blood glucose and liver triglyceride levels caused by AR reduced hepatic gluconeogenesis. The opposite phenotypes identified in H-ARKO and castrated H-ARTG mice support the critical role of activated AR in decreasing gluconeogenesis and triglyceride levels in liver. Hepatic AR acting by enhancing the expression of cytosolic glycerol-3-phosphate dehydrogenase (cGPDH), a key of glycerophosphate shuttle, was identified as one mechanism to decrease gluconeogenesis from glycerol. We further found AR normally expressed in zone 3 of hepatic lobules. Its level fluctuates dependent on the demand of glucose, decreased by fasting but increased by glucose uptake or insulin stimulation., Conclusion: AR is a newly identified zone 3 hepatic gene with function in reducing blood glucose and body weight in mice. It suggests that stabilization of hepatic AR is a new direction to prevent hyperglycemia, obesity and nonalcoholic fatty liver disease (NAFLD) in males., Competing Interests: Declaration of competing interest Nothing to report., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Development of specific antiviral agents is an urgent unmet need for SARS-coronavirus 2 (SARS-CoV-2) infection. This study focuses on host proteases that proteolytically activate the SARS-CoV-2 spike protein, critical for its fusion after binding to angiotensin-converting enzyme 2 (ACE2), as antiviral targets. We first validate cleavage at a putative furin substrate motif at SARS-CoV-2 spikes by expressing it in VeroE6 cells and find prominent syncytium formation. Cleavage and the syncytium are abolished by treatment with the furin inhibitors decanoyl-RVKR-chloromethylketone (CMK) and naphthofluorescein, but not by the transmembrane protease serine 2 (TMPRSS2) inhibitor camostat. CMK and naphthofluorescein show antiviral effects on SARS-CoV-2-infected cells by decreasing virus production and cytopathic effects. Further analysis reveals that, similar to camostat, CMK blocks virus entry, but it further suppresses cleavage of spikes and the syncytium. Naphthofluorescein acts primarily by suppressing viral RNA transcription. Therefore, furin inhibitors may be promising antiviral agents for prevention and treatment of SARS-CoV-2 infection., Competing Interests: Declaration of Interests The authors declare no competing interests., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

Most hepatocellular carcinomas (HCCs) develop in patients with chronic hepatitis, which creates a microenvironment for the growth of hepatic progenitor cells (HPCs) at the periportal area and subsequent development of HCCs. We investigated the signal from the inflammatory liver for this pathogenic process in the hepatic conditional β-catenin knockout mouse model. Senescent β-catenin-depleted hepatocytes in aged mice create an inflammatory microenvironment that stimulates periportal HPC expansion but arrests differentiation, which predisposes mice to the development of liver tumors. The release of complement C1q from macrophages in the inflammatory niche was identified as the unorthodox signal that activated the β-catenin pathway in periportal HPCs and was responsible for their expansion and de-differentiation. C1q inhibitors blocked the β-catenin pathway in both the expanding HPCs and the liver tumors but spared its orthodox pathway in pericentral normal hepatocytes. This mechanism has been validated in human liver specimens from patients with chronic hepatitis. Taken together, these results demonstrate that C1q- mediated activation of β-catenin pathway in periportal HPCs is a previously unrecognized mechanism for replenishing hepatocytes in the inflammatory liver and, if unchecked, for promoting hepatocarcinogenesis. C1q may become a new target for blocking carcinogenesis in patients with chronic hepatitis., Competing Interests: The authors declare no competing interest.

Background: Obesity-induced hepatocellular carcinoma (HCC) is more prevalent in males than in females, but the underlying mechanism remains unclear. The influence of hepatic androgen receptor (AR) pathway on the gender difference of HCC has been well documented. Here we investigated the role of hepatic lipogenesis, which is elevated in the livers of obese and nonalcoholic fatty liver disease (NAFLD) patients, in stimulating the AR pathway for the male preference of obesity induced HCC., Methods: Male C57BL/6J mice were fed a fructose-rich high carbohydrate diet (HCD) to induce hepatic lipogenesis. The effect of hepatic lipogenesis on AR was examined by the expression of hydrodynamically injected AR reporter and the endogenous AR target gene; the mechanism was delineated in hepatoma cell lines and validated in male mice., Results: The hepatic lipogenesis induced by a fructose-rich HCD enhanced the transcriptional activity of hepatic AR in male mice, which did not happen when fed a high fat diet. This AR activation was blocked by sh-RNAs or inhibitors targeting key enzymes in lipogenesis, either acetyl-CoA carboxylase subunit alpha (ACCα), or fatty acid synthase (FASN), in vivo and in vitro. Further mechanistic study identified that specific unsaturated fatty acid, the oleic acid (C18:1 n-9), incorporated DAGs produced by hepatic lipogenesis are the key molecules to enhance the AR activity, through activation of Akt kinase, and this novel mechanism is targeted by metformin., Conclusions: Our study elucidates a novel mechanism underlying the higher risk of HCC in obese/NAFLD males, through specific DAGs enriched by hepatic lipogenesis to increase the transcriptional activity of hepatic AR, a confirmed risk factor for male HCC.

To understand the mechanism(s) of age-dependent outcomes of hepatitis B virus (HBV) infection in humans, we previously established an age-related HBV mouse model in which 6-week-old (N6W) C3H/HeN mice exhibited virus tolerance whereas 12-week-old (N12W) counterparts presented virus clearance. By investigating the hepatic myeloid cell dynamics in mice of these two ages, we aim to identify factors associated with HBV clearance. C3H/HeN mice were transfected with an HBV plasmid by hydrodynamic injection. Serum HBV markers were monitored weekly. Hepatic leucocyte populations and their cytokine/chemokine productions were examined at baseline, day 3 (D3), day 7 (D7), and day 14 after injection. C-C chemokine receptor type 2 (CCR2) antagonist and clodronate (CLD) were respectively administered to N12W and N6W mice to study the roles of lymphocyte antigen 6 complex, locus C (Ly6C) + monocytes and Kupffer cells (KCs) in viral clearance. N12W mice had a significantly higher number of TNF-α-secreting Ly6C + monocytes and fewer IL-10-secreting KCs at D3 in the liver than their younger N6W counterparts after HBV transfection. In addition, the elevated number of interferon-γ + TNF-α + CD8 + T cells at D7 was only seen in the older cohort. The enhanced Ly6C + monocyte induction in N12W mice resulted from elevated C-C motif chemokine ligand 2 (CCL2) secretion by hepatocytes. CCR2 antagonist administration hampered Ly6C + monocyte recruitment and degree of KC reduction and delayed HBV clearance in N12W animals. Depletion of KCs by CLD liposomes enhanced Ly6C + monocyte recruitment and accelerated HBV clearance in N6W mice. Conclusions: Ly6C + monocytes and KCs may, respectively, represent the resistance and tolerance arms of host defenses. These two cell types play an essential role in determining HBV clearance/tolerance. Manipulation of these cells is a promising avenue for immunotherapy of HBV-related liver diseases., (© 2019 by the American Association for the Study of Liver Diseases.)

Background/purpose: Daclatasvir is a nonstructural protein 5A inhibitor with potent activity against hepatitis C virus genotypes 1-6 in vitro, and asunaprevir is a nonstructural protein 3 protease inhibitor with activity against genotypes 1, 4, 5, and 6. Despite a 90% sustained virologic response (SVR) rate, the SVR rate in patients with baseline NS5A-L31/Y93H polymorphisms decreased to around 40%. Therefore, an alternative regimen under the consideration of cost-effectiveness would be important. Whether the addition of ribavirin could improve the SVR rate among this group of patients remains unknown and hence our case series was reported., Methods: For six adult chronic hepatitis C 1b patients with a pre-existing NS5A-Y93H (>20%) polymorphism, we added ribavirin (800 mg/d) to daclatasvir/asunaprevir for 24 weeks and followed through 12-weeks post-treatment. Four of these patients received interferon/ribavirin treatment before but relapsed, while the other two were naïve cases. Two of them had liver cirrhosis and one had hepatocellular carcinoma postcurative therapy. The primary efficacy end-point was undetectable hepatitis C virus RNA (hepatitis C virus RNA level of<25 IU/mL) at 12 weeks after the end of the treatment (SVR12)., Results: In total, five cases reached SVR12 eventually (SVR rate: 83%; 95% confidence interval: 18.6-99.1%). However, the viral load of one remaining patient rebounded from the 24 th week of treatment. No patients developed significant adverse effects during and after the treatment., Conclusion: In genotype 1b chronic hepatitis C patients with NS5A-Y93H polymorphism, the addition of ribavirin to daclatasvir/asunaprevir may increase the SVR12 rate with minimal side effects, and thus deserves more comprehensive trials in resource-limited areas., (Copyright © 2016. Published by Elsevier B.V.)

Aim: The aim of this study was to explore the community-level risk factors, such as high hepatitis C viruse (HCV)-RNA positive rate and limited medical resources in a township, for HCV infection, one major cause of liver cirrhosis and hepatocellular carcinoma., Methods: This study enrolled 23,820 residents living in 155 villages of seven townships in Taiwan in 1991-2 to explore both individual and community risk factors for HCV infection. Antibodies against HCV (anti-HCV), HCV-RNA and HCV genotype in serum samples were determined by enzyme immunoassay, PCR and melting curve analysis, respectively., Results: The overall anti-HCV seroprevalence was 5.5%, HCV-RNA was detectable in 68.1% of the seropositives of anti-HCV, and genotype 1 was the most prevalent genotype (54.6%). Personal risk factors for the seropositivity of anti-HCV included older age, female gender, low educational level and history of blood transfusion. Based on the multilevel analysis, persons living in villages with high HCV-RNA-positive rates and limited healthcare resources had an increased seroprevalence of anti-HCV after adjustment for individual risk factors. The multivariate-adjusted prevalence OR (95% CI) was 3.49 (1.80 to 6.76) and 8.48 (5.07 to 14.20) for villages with medium and high HCV-RNA positive rate, respectively. The multivariate-adjusted OR (95% CI) was was 1.75 (0.76 to 4.01) and 3.91 (2.25 to 6.80), respectively, for villages with medium and poor healthcare resources., Conclusions: This study suggests that community risk factors contribute significantly to the variation in anti-HCV seroprevalence. It implies both the adequacy of healthcare resources and the treatment of patients positive for HCV-RNA may prevent individual residents from the acquisition of HCV infection from the community.

Purpose: Hepatitis C virus (HCV) contributes to one third of hepatocellular carcinoma cases worldwide. Long-term predictors for HCV-related hepatocellular carcinoma are essential for early intervention. Serum HCV RNA and ALT levels and HCV genotype were assessed for their predictability of hepatocellular carcinoma risk., Methods: A prospective cohort of 925 participants positive for antibodies against HCV and age 30 to 65 years was recruited and followed from 1991 to 2006. Serum HCV RNA and ALT levels and HCV genotypes at enrollment and during follow-up were examined. Newly developed hepatocellular carcinoma was identified by health examination and computerized linkage with national cancer registration and death certification profiles. Multivariate adjusted hazard ratios with 95% CIs were estimated using Cox regression models., Results: Fifty-five participants newly developed hepatocellular carcinoma during 8,476 person-years of follow-up, giving an incidence rate of 648.9 per 100,000 person-years. The cumulative hepatocellular carcinoma risk increased from 1.1% for HCV RNA seronegative status to 6.4% for low HCV RNA levels and to 14.7% for high HCV RNA levels (P < .001). The cumulative risk also increased with elevated serum ALT levels from 1.7% for persistently ≤ 15 U/L to 4.2% for ever more than 15 U/L but never more than 45 U/L and to 13.8% for ALT ever ≥ 45 U/L (P < .001). Having HCV genotype 1 was associated with a higher cumulative hepatocellular carcinoma risk (12.6%) than not having HCV genotype 1 (4.5%; P < .001)., Conclusion: Elevated serum levels of HCV RNA and ALT and HCV genotype 1 infection are independent risk predictors of hepatocellular carcinoma. These findings have strong implications for the management of chronic HCV.

Men have a higher incidence of hepatocellular carcinoma (HCC) than women. Epidemiologic and animal studies have suggested that it might be due to the stimulatory effects of androgen and the protective effects of estrogen. Recently, increasing molecular mechanisms underlying the carcinogenic effect of both sex hormones were reported. Knockout of androgen receptor (AR) expression in hepatocytes delayed the development of N',N'-diethylnitrosamine (DEN)-induced HCC, suggesting the active AR pathway in augmenting the HCC risk. Moreover, an intriguing interaction between the viral protein of hepatitis B virus X protein (HBx) and the androgen pathway was established. HBx can enhance the transcriptional activity of AR in a ligand concentration-dependent manner, mainly through its effects on the c-Src and GSK-3beta kinase pathways. The studies from the DEN-induced HCC mouse model further provided a mechanism for the protective role of estrogen in female HCC. Estrogen can protect hepatocytes from malignant transformation via downregulation of IL-6 release from Kupffer cells, a critical process in this mouse model. Intriguingly, suppression of the ERalpha protein by overexpression of miR-18a, which occurs preferentially in female HCC, was identified as a novel mechanism to block the tumor-protective function of estrogen in female HCC. In conclusion, the current studies demonstrated that the gender disparity of HCC is attributed by both androgen and estrogen sex hormone pathways, with distinct roles in each gender. Therefore, the ligand and the receptor factors of both sex hormones need to be included for assessing the relative risk of HCC patients of each gender., (Copyright (c) 2010 S. Karger AG, Basel.)

Allelic loss of chromosome 4q is one of the most frequent genetic aberrations found in human hepatocellular carcinoma (HCC) and suggests the presence of putative tumor suppressor genes within this region. To precisely define the region containing these tumor suppressor genes for further positional cloning, we tried a detailed deletion mapping strategy in 149 HCCs by using 49 microsatellite markers covering 4q12 approximately 25. A common region with allelic loss has been identified based on the interstitial deletions occurring within it; this region is found between D4S1534 and D4S1572 (a 17.5-cM genetic interval). When we included all cases with limited aberration regions for comparison, 2 smaller regions were derived: 1 between D4S1534 and D4S2460 (3.52 cM) and 1 between D4S2433 and D4S1572 (8.44 cM). A few candidate genes were found to be down-regulated in HCCs, but without sequence mutations. In these HCCs, 4q alleleic loss was associated with hepatitis B virus infection status and the elevation of serum alpha-fetoprotein (>/=400 ng/mL). In conclusion, the current study not only mapped a common allelic loss region on chromosome 4q, but it also revealed that its loss may be involved in hepatitis B virus-related hepatocarcinogenesis and the elevation of serum alpha-fetoprotein.

Since early March 2003, the severe acute respiratory syndrome (SARS) coronavirus (CoV) infection has claimed 346 cases and 37 deaths in Taiwan. The epidemic occurred in two stages. The first stage caused limited familial or hospital infections and lasted from early March to mid-April. All cases had clear contact histories, primarily from Guangdong or Hong Kong. The second stage resulted in a large outbreak in a municipal hospital, and quickly spread to northern and southern Taiwan from late April to mid-June. During this stage, there were some sporadic cases with untraceable contact histories. To investigate the origin and transmission route of SARS-CoV in Taiwan's epidemic, we conducted a systematic viral lineage study by sequencing the entire viral genome from ten SARS patients. SARS-CoV viruses isolated from Taiwan were found closely related to those from Guangdong and Hong Kong. In addition, all cases from the second stage belonged to the same lineage after the municipal hospital outbreak, including the patients without an apparent contact history. Analyses of these full-length sequences showed a positive selection occurring during SARS-CoV virus evolution. The mismatch distribution indicated that SARS viral genomes did not reach equilibrium and suggested a recent introduction of the viruses into human populations. The estimated genome mutation rate was approximately 0.1 per genome, demonstrating possibly one of the lowest rates among known RNA viruses.

The CAG polymorphism in exon 1 of the androgen receptor (AR) gene has been shown associated with the development of human male hepatocellular carcinoma (HCC) with the shorter AR alleles conferring a higher risk. However, the significance of AR-CAG repeats in female hepatocarcinogenesis remains to be addressed. In this study, seventy-six pairs of female HCCs and corresponding nontumorous tissues were collected, and 180 cirrhotic nodules were microdissected from 7 cirrhotic livers. The clonality status, functional AR alleles, and CAG repeat number of each sample were determined by AR methylation analysis. In a total of 44 monoclonal HCCs, the mean of CAG repeats in the active alleles was significantly longer than that in the inactive alleles (22.0 +/- 2.8 versus 20.7 +/- 3.6; P = 0.047). When we divided HCCs into hepatitis B virus-positive [HBV(+)] and HBV(-) subgroups, the long AR allele dominance was found only in HBV(+) ones (P = 0.006 versus P = 0.923). Notably, the preference of long CAG repeat has also been found in the 100 monoclonal nodules (P = 0.013). For comparison of monoclonal nodules obtained from the same individual, a dominant long AR allele was found in 6 patients. The proportion of monoclonal cirrhotic nodules and HCCs expressing longer AR allele, 69 and 68%, are both significantly higher than 50%, the assumed value in normal liver (P < 0.001 for cirrhotic nodules and P = 0.005 for HCC). The dominance is again only prominent in HBV-infected HCCs [85% for HBV(+) HCC; P < 0.001 but 54% for HBV(-) HCC; P = 0.27]. The results indicated that in female hepatocarcinogenesis, hepatocytes expressing the longer AR allele seem to be favorably selected for autonomous growth and transformation, especially in synergy with HBV infection.