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1.
Hepatology ; 64(3): 720-31, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27228506

RESUMO

UNLABELLED: To evaluate how hepatitis B virus (HBV) genetic variation affected progression from chronic carrier state to hepatocellular carcinoma (HCC), we analyzed HBV full-length sequences in blood obtained <1-20 years before diagnosis from 117 HCC cases and 118 controls nested in a cohort of 4,841 HBV carriers, for whom HBV genotypes B and C are predominant. The relationship between each viral single-nucleotide polymorphism (SNP) and HCC development was assessed using ordinal logistic models according to five periods of time to diagnosis (TTD). Thirty-one HBV-SNPs showed significant association with TTD after adjustment for HBV genotype, 24 of which could also be analyzed with an extended analysis on the full-length data in conjunction with 512 partial sequences (nucleotides 2,436-1,623) from the cohort. The obtained 10 robust candidate HBV-SNPs (P ≤ 0.0304), which showed odds ratios ranging from 1.89 to 8.68, were further confirmed in 163 GenBank HBV-HCC sequences from nine Asia regions, assayed after HCC diagnosis, representing the end stage of progressive hepatic diseases. The prevalence of these HBV-SNPs and their cumulative number, presented in terms of mutation score, increased with time approaching HCC diagnosis, with an odds ratio of 2.17, 4.21, 8.15, and 19.15, respectively, for the mutation score of 1, 2, 3, and ≥4 versus 0. The mutation score for predicting short-term HCC risk outperformed other factors, including HBV-DNA levels, viral genotype, and various combinations of risk factors, and revealed increasing accuracy with shorter TTD (<4.5 years before diagnosis: area under the curve = 0.83-0.89; sensitivity = 72.7%-94.1%; specificity = 58.3%-70.5%; conditioned on optimized cutoff for genotype B and C, respectively). CONCLUSIONS: Identifying and tracking viral mutations is important for monitoring hepatitis B progression and early detection of HCC. (Hepatology 2016;64:720-731).


Assuntos
Carcinoma Hepatocelular/virologia , Vírus da Hepatite B/genética , Neoplasias Hepáticas/virologia , Acúmulo de Mutações , Adulto , Carcinoma Hepatocelular/diagnóstico , Estudos de Casos e Controles , Estudos de Coortes , Genoma Viral , Humanos , Neoplasias Hepáticas/diagnóstico , Masculino , Pessoa de Meia-Idade , Mutação
2.
PLoS One ; 8(7): e70169, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23936156

RESUMO

OBJECTIVE: The hepatitis B virus (HBV)-polymerase region overlaps pre-S/S genes with high epitope density and plays an essential role in viral replication. We investigated whether genetic variation in the polymerase region determined long-term dynamics of viral load and the risk of hepatitis B progression in a population-based cohort study. METHODS: We sequenced the HBV-polymerase region using baseline plasma from treatment-naïve individuals with HBV-DNA levels≥1000 copies/mL in a longitudinal viral-load study of participants with chronic HBV infection followed-up for 17 years, and obtained sequences from 575 participants (80% with HBV genotype Ba and 17% with Ce). RESULTS: Patterns of viral sequence diversity across phases (i.e., immune-tolerant, immune-clearance, non/low replicative, and hepatitis B e antigen (HBeAg)-negative hepatitis phases) of HBV-infection, which were associated with viral and clinical features at baseline and during follow-up, were similar between HBV genotypes, despite greater diversity for genotype Ce vs. Ba. Irrespective of genotypes, however, HBeAg-negative participants had 1.5-to-2-fold higher levels of sequence diversity than HBeAg-positive participants (P<0.0001). Furthermore, levels of viral genetic divergence from the population consensus sequence, estimated by numbers of nucleotide substitutions, were inversely associated with long-term viral load even in HBeAg-negative participants. A mixed model developed through analysis of the entire HBV-polymerase region identified 153 viral load-associated single nucleotide polymorphisms in overall and 136 in HBeAg-negative participants, with distinct profiles between HBV genotypes. These polymorphisms were most evident at sites within or flanking T-cell epitopes. Seven polymorphisms revealed associations with both enhanced viral load and a more than 4-fold increased risk of hepatocellular carcinoma and/or liver cirrhosis. CONCLUSIONS: The data highlight a role of viral genetic divergence in the natural course of HBV-infection. Interindividual differences in the long-term dynamics of viral load is not only associated with accumulation of mutations in HBV-polymerase region, but differences in specific viral polymorphisms which differ between genotypes.


Assuntos
Genes Virais , Heterogeneidade Genética , Vírus da Hepatite B/genética , Hepatite B Crônica/virologia , Carga Viral , Adulto , Carcinoma Hepatocelular/etiologia , Progressão da Doença , Genótipo , Vírus da Hepatite B/enzimologia , Vírus da Hepatite B/patogenicidade , Hepatite B Crônica/complicações , Humanos , Cirrose Hepática/etiologia , Pessoa de Meia-Idade , Mutação , Polimorfismo de Nucleotídeo Único , Virulência/genética
3.
Atherosclerosis ; 219(1): 349-54, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21840004

RESUMO

Polymorphisms of the apolipoprotein E gene (ApoE) have been associated with health and longevity. Numerous studies have linked ApoE to health outcomes including cardiovascular disease and mortality, but far fewer studies have examined the relationship of ApoE to other biological markers of health. This study investigates the relationship between ApoE and mortality, as well as ApoE and a set of biomarkers related to cardiovascular and immune function, in a population-based sample of Taiwanese adults ages 54+. ApoE £2 carriers were less likely to have at-risk levels of high-density lipoprotein (HDL-C) and total cholesterol (total-C) than non-carriers (odds ratio [OR] 0.45, 95% confidence interval [CI] 0.25-0.83 and OR 0.45, 95% CI 0.29-0.71, respectively). ApoE £4 carriers were less likely to have elevated levels of C-reactive protein (CRP) than non-carriers (OR 0.62, 95% CI 0.39-0.96). ApoE genotype was not, however, associated with mortality after 8 years of follow-up. Our findings confirm the association between ApoE £2and cholesterol levels, suggesting a potential protective effect of ApoE £2 on blood lipids. They also contribute to reports on the relationship between ApoE £4 carrier status and lower CRP levels.


Assuntos
Apolipoproteínas E/genética , Inflamação/genética , Lipídeos/sangue , Idoso , Idoso de 80 Anos ou mais , Apolipoproteínas E/sangue , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Colesterol/sangue , Feminino , Seguimentos , Genótipo , Humanos , Inflamação/sangue , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Fatores de Risco , Análise de Sobrevida , Taiwan/epidemiologia
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