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1.
Clin Cancer Res ; 15(9): 3205-13, 2009 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-19383824

RESUMO

PURPOSE: Hepatitis C virus (HCV) infection can promote the development of hepatocellular carcinoma (HCC). Published data implicate the HCV core gene in oncogenesis. We tested the hypothesis that core gene sequences from HCC patients differ from those of patients without cirrhosis/HCC. EXPERIMENTAL DESIGN: Full-length HCV sequences from HCC patients and controls were obtained from the investigators and GenBank and compared with each other. A logistic regression model was developed to predict the HCC risk of individual point mutations and other sequence features. Mutations in partial sequences (bases 36-288) from HCC patients and controls were also analyzed. The first base of the AUG start codon was designated position 1. RESULTS: A logistic regression model developed through analysis of full-length core gene sequences identified seven polymorphisms significantly associated with increased HCC risk (36G/C, 209A, 271U/C, 309A/C, 435A/C, 481A, and 546A/C) and an interaction term (for 209A-271U/C) that had an odds ratio <1.0. Three of these polymorphisms could be analyzed in the partial sequences. Two of them, 36G/C and 209A, were again associated with increased HCC risk, but 271U/C was not. The odds ratio of 209A-271U/C was not significant. CONCLUSIONS: HCV core genes from patients with and without HCC differ at several positions. Of interest, 209A has been associated with IFN resistance and HCC in previous studies. Our findings suggest that HCV core gene sequence data might provide useful information about HCC risk. Prospective investigation is needed to establish the temporal relationship between appearance of the viral mutations and development of HCC.


Assuntos
Carcinoma Hepatocelular/etiologia , Hepacivirus/genética , Cirrose Hepática/etiologia , Neoplasias Hepáticas/etiologia , Mutação/genética , Proteínas do Core Viral/genética , Carcinoma Hepatocelular/patologia , Estudos de Casos e Controles , Hepatite C/complicações , Hepatite C/genética , Hepatite C/virologia , Humanos , Cirrose Hepática/patologia , Neoplasias Hepáticas/patologia , Proteínas do Core Viral/metabolismo
2.
J Hepatol ; 51(1): 11-20, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19345439

RESUMO

BACKGROUND/AIMS: In the GLOBE trial, telbivudine treatment was identified as a significant, independent predictor of better outcomes at 2 years. We analyzed all telbivudine recipients in this trial to determine the predictors of optimal outcomes. METHODS: The intent-to-treat population comprised 458 HBeAg-positive and 222 HBeAg-negative telbivudine-treated patients. Multivariate logistic regression analyses were employed to evaluate baseline and/or early on-treatment variables. RESULTS: Baseline HBV DNA<9 log(10)copies/mL, or ALT levels > or = 2x above normal were strong pretreatment predictors for HBeAg-positive, but not for HBeAg-negative patients. However, non-detectable serum HBV DNA at treatment week 24 (TW24) was the strongest predictor for better outcomes for both groups. A combination of pretreatment characteristics plus TW24 response identified subgroups with the best outcomes: (1) HBeAg-positive patients with baseline HBV DNA<9 log(10)copies/mL, ALT > or = 2x above normal and non-detectable HBV DNA at TW24 achieved at 2 years: non-detectable HBV DNA in 89%, HBeAg seroconversion in 52%, telbivudine resistance in 1.8%; and (2) HBeAg-negative patients with baseline HBV DNA<7 log(10)copies/mL and non-detectable serum HBV DNA at TW24 achieved at 2 years: non-detectable HBV DNA in 91%, telbivudine resistance in 2.3%. CONCLUSION: During telbivudine treatment, non-detectable serum HBV DNA at treatment week 24 is the strongest predictor for optimal outcomes at 2 years.


Assuntos
Antivirais/uso terapêutico , Nucleosídeos/uso terapêutico , Pirimidinonas/uso terapêutico , Adolescente , Adulto , Idoso , Alanina Transaminase/sangue , DNA Viral/sangue , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/virologia , Humanos , Pessoa de Meia-Idade , Telbivudina , Timidina/análogos & derivados , Resultado do Tratamento
3.
J Virol ; 79(5): 3071-83, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15709027

RESUMO

A series of 29 patients undergoing treatment for chronic hepatitis C virus (HCV) genotype 1 infection with pegylated alpha-2a interferon plus ribavirin were studied for patterns of response to antiviral therapy and viral quasispecies evolution. All patients were treatment naive and had chronic inflammation and fibrosis on biopsy. As part of an analysis of pretreatment variables that might affect the outcome of treatment, genetic heterogeneity within the viral E1-E2 glycoprotein region (nucleotides 851 to 2280) was assessed by sequencing 10 to 15 quasispecies clones per patient from serum-derived PCR products. Genetic parameters were examined with respect to response to therapy based on serum viral RNA loads at 12 weeks (early viral response) and at 24 weeks posttreatment (sustained viral response). Nucleotide and amino acid quasispecies complexities of the hypervariable region 1 (HVR-1) were less in the responder group in comparison to the nonresponder group at 12 weeks, and genetic diversity was also less both within and outside of the HVR-1, with the difference being most pronounced for the non-HVR-1 region of E2. However, these genetic parameters did not distinguish responders from nonresponders for sustained viral responses. Follow-up studies of genetic heterogeneity based on the HVR-1 in selected responders and nonresponders while on therapy revealed greater evolutionary drift in the responder subgroup. The pretreatment population sequences for the NS5A interferon sensitivity determinant region were also analyzed for all patients, but no correlations were found between treatment response and any distinct genetic markers. These findings support previous studies indicating a high level of genetic heterogeneity among chronically infected HCV patients. One interpretation of these data is that early viral responses are governed to some extent by viral factors, whereas sustained responses may be more influenced by host factors, in addition to effects of viral complexity and diversity.


Assuntos
Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Proteínas do Envelope Viral/genética , Adolescente , Adulto , Idoso , Sequência de Aminoácidos , Sequência de Bases , DNA Viral/genética , Feminino , Variação Genética , Hepacivirus/classificação , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Filogenia , RNA Viral/sangue , RNA Viral/genética , Proteínas Recombinantes , Homologia de Sequência de Aminoácidos , Fatores de Tempo , Proteínas não Estruturais Virais/genética
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