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1.
Hepatol Res ; 43(8): 865-75, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23279319

RESUMO

AIM: Prediction of treatment responses to pegylated interferon (PEG IFN) plus ribavirin (RBV) therapy is uncertain for genotype 1b chronic hepatitis C. METHODS: In this study, 96 patients were investigated for the correlation between 36 pretreatment serum chemokine/cytokine levels and PEG IFN/RBV treatment efficacy by a sandwich enzyme-linked immunoassay (ELISA) and a bead array. RESULTS: First, chemokines/cytokines were measured semiquantitatively by sandwich ELISA in 31 randomly-selected patients and the serum regulated on activation normal T-cell expressed and secreted (RANTES) level was found to be significantly higher in the sustained virological response (SVR) group than the non-SVR group (P = 0.048). Precise RANTES measurement in all 96 patients using a bead array confirmed this correlation (P = 0.002). However, the genetic RANTES haplotype was not significantly related to the serum level. The serum RANTES level was extracted by multivariate analysis (odds ratio = 4.09, 95% confidence interval = 1.02-16.5, P = 0.048) as an independent variable contributing to SVR. CONCLUSION: The serum RANTES level is an important determinant influencing the virological response to PEG IFN/RBV therapy in chronic hepatitis C.

2.
J Med Virol ; 84(9): 1360-8, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22825814

RESUMO

The emergence of amino acid or nucleotide substitutions leads to lamivudine resistance in hepatitis B virus (HBV) infected patients. The aim of this study was to investigate whether viral sequences help predict the emergence of lamivudine resistance. The study subjects comprised 59 consecutive patients infected with HBV treated with daily therapy of 100 mg lamivudine. Among those, 32 patients with adequate pretreatment serum preservation were investigated for the correlation between viral amino acid substitutions and the appearance of lamivudine resistance with consideration of clinical background by determining dominant HBV full open reading frames. Viral resistance to lamivudine emerged in 28 of 59 patients (47%) in a median period of 2.45 years. Sequence comparisons of HBV genomes between patients who later developed lamivudine resistance and patients who did not revealed the existence of significant differences between the two groups in the pre-S1 84 (P = 0.042), pre-S2 1 (P = 0.017) and 22 (P = 0.015), and polymerase tp 95 (P = 0.046), judged by a log-rank test. Viral sequence analyses revealed the presence of amino acid substitutions in HBV pre-S1 and pre-S2 that may be associated with the emergence of lamivudine resistance during chronic HBV infection.


Assuntos
Farmacorresistência Viral/genética , Vírus da Hepatite B/genética , Hepatite B Crônica/virologia , Lamivudina/farmacologia , Inibidores da Transcriptase Reversa/farmacologia , Adulto , Idoso , Alanina Transaminase/sangue , Sequência de Aminoácidos , Substituição de Aminoácidos , DNA Viral/sangue , DNA Viral/genética , Feminino , Produtos do Gene pol/genética , Genes Virais , Vírus da Hepatite B/enzimologia , Hepatite B Crônica/sangue , Hepatite B Crônica/enzimologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Análise Multivariada , Fases de Leitura Aberta , Análise de Sequência de DNA , Estatísticas não Paramétricas
3.
Hepatology ; 56(5): 1611-21, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22577043

RESUMO

UNLABELLED: To comprehensively characterize the contribution of virological factors as well as interleukin-28B (IL28B) single-nucleotide polymorphisms (SNPs) in determining treatment responses in pegylated-interferon plus ribavirin (Peg-IFN/RBV) therapy for chronic hepatitis C virus (HCV)-1b infection, we undertook a retrospective cohort analysis for the pretreatment dominant complete HCV open reading frame (ORF) amino-acid (aa) sequence study in 103 consecutive HCV-1b Japanese patients. The dominant HCV sequences classified by the response were subjected to systematic sliding-window comparison analysis to characterize response-specific viral sequences, along with IL28B SNP analyses (rs8099917). In each comparison of the patients between with and without rapid viral response (RVR), nonearly viral response (nEVR), sustained virological response (SVR), or relapse, the following regions were extracted as most significantly associated with the different responses respectively: nonstructural protein 5A (NS5A) aa.2224-2248 (P = 1.2E-07); core aa.70 (P = 4E-04); NS5A aa.2340-2382 (P = 7.0E-08); and NS5A aa.2360-2377 (P = 1.1E-05). Those NS5A regions nearly coincided with the interferon (IFN) sensitivity-determining region (NS5A aa.2209-2248) and the IFN/RBV resistance-determining region (NS5A aa.2339-2379). In a multivariate analysis, the IL28B SNP (odds ratio [OR] = 16.8; P = 0.009) and NS5A aa.2340-2382 (OR = 13.8; P = 0.0003) were extracted as the two most-significant independent variables contributing to the final outcome. CONCLUSION: In Peg-IFN/RBV therapy, polymorphisms in IL28B, NS5A aa.2224-2248, core aa.70, and, most important, NS5A aa.2340-2382 have a tremendous influence on treatment response in association with viral kinetics, resulting in significantly different outcomes in chronic HCV-1b infection.


Assuntos
Antivirais/uso terapêutico , Farmacorresistência Viral/genética , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/genética , Interleucinas/genética , Proteínas não Estruturais Virais/genética , Adolescente , Adulto , Idoso , Alelos , Feminino , Genótipo , Humanos , Interferons/uso terapêutico , Japão , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Fases de Leitura Aberta , Polietilenoglicóis/uso terapêutico , Polimorfismo de Nucleotídeo Único , Recidiva , Estudos Retrospectivos , Ribavirina/uso terapêutico , Resultado do Tratamento
4.
Hepatol Int ; 6(2): 482-90, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22020822

RESUMO

BACKGROUND AND AIMS: Protease inhibitor (PI)-resistant hepatitis C virus (HCV) variants may be present in substantial numbers in PI-untreated patients according to recent reports. However, influence of these viruses in the clinical course of chronic hepatitis C has not been well characterized. METHODS: The dominant HCV nonstructural 3 (NS3) amino acid sequences were determined in 261 HCV genotype 1b-infected Japanese patients before pegylated interferon plus ribavirin (PEG-IFN/RBV) therapy, and investigated the patients' clinical characteristics as well as treatment responses including sustained virological response (SVR) rate. HCV-NS3 sequences were also determined in 39 non-SVR patients after completion of the therapy. RESULTS: Four single mutations (T54S, Q80K, I153V, and D168E) known to confer PI resistance were found in 35 of 261 patients (13.4%), and double mutations (I153V plus T54S/D168E) were found in 6 patients (2.3%). Responses to PEG-IFN/RBV therapy did not differ between patients with and without PI-resistance mutations (mutation group, SVR 48%; wild-type group, SVR 40%; P = 0.38). On the other hand, two mutations appeared in two non-SVR patients after PEG-IFN/RBV therapy (I153V and E168D, 5.1%). CONCLUSIONS: PI-resistance-associated NS3 mutations exist in a substantial proportion of untreated HCV-1b-infected patients. The impact of these mutations in the treatment of PIs is unclear, but clinicians should pay attention to avoid further development of PI resistance.

5.
Hepatol Int ; 6(1): 386-96, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22020823

RESUMO

BACKGROUND AND AIMS: The association between hepatitis C virus (HCV) sequences with interleukin 28B (IL28B) single-nucleotide polymorphism (SNP) in the development of hepatocellular carcinoma (HCC) has not been well clarified. METHODS: Complete HCV open-reading frame sequences were determined in 20 patients developing HCC and 23 non-HCC patients with HCV-1b infection in two distant time points. An additional 230 patients were studied cross-sectionally for core and NS5A sequences with HCC development. Among them, 98 patients with available samples were investigated for changes in viral core sequences over time. Finally, IL28B SNPs and HCC development were investigated in 228 patients. RESULTS: During observation period (HCC for 10.8 years, and non-HCC for 11.1 years), changes in core a.a. 70 and three amino acid positions in NS5A were characteristics of the patients developing HCC. In 230 patients, Q (glutamine) or H (histidine) to R (arginine) ratio at core a.a. 70 was significantly higher in the HCC group (HCC group 43:22 vs. non-HCC group 66:99, p = 0.001). A change in core R70Q was observed over time in 11 patients associated with a decrease in platelets (p = 0.005) and albumin (p = 0.005), while a Q70R change was observed in 4 patients without associated changes in platelets (nonsignificant) and albumin (nonsignificant). IL28B SNP showed significant correlation with the core a.a. 70 residue. There was no evident link between IL28B SNPs and the occurrence of HCC. CONCLUSIONS: Hepatitis C virus core a.a. 70 residue is associated with liver disease progression and is independent factor for HCC development in genotype-1b infection. IL28B SNPs are related to core a.a. 70 residue, but not to HCC. The functional relevance of core a.a. 70 residue in hepatitis C pathogenesis should be further investigated.

6.
PLoS One ; 6(9): e24514, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21935415

RESUMO

BACKGROUND AND AIMS: Patients infected with genotype 2b hepatitis C virus (HCV) generally can achieve favorable responses to pegylated-interferon plus ribavirin therapy (PEG-IFN/RBV). However, a proportion of patients show poorer responses and the correlation between viral sequence variation and treatment outcome remains unclear. METHODS: The pretreatment complete open reading frame (ORF) sequences of genotype 2b HCV determined by direct sequencing were investigated for correlation with the final outcome in a total of 60 patients. RESULTS: In this study group, 87.5% (14/16) of non-sustained virological response (non-SVR) patients (n = 16) were relapsers. Compared to sustained virological response (SVR) patients (n = 44), non-SVR patients were older and could not achieve prompt viral clearance after the therapy induction. Comparing each viral protein between the two groups, viral sequences were more diverse in SVR patients and that diversity was found primarily in the E1, p7, and NS5A proteins. In searching for specific viral regions associated with the final outcome, several regions in E2, p7, NS2, NS5A, and NS5B were extracted. Among these regions, part of the interferon sensitivity determining region (ISDR) was included. In these regions, amino acid substitutions were associated with the final outcome in an incremental manner, depending upon the number of substitutions. CONCLUSIONS: Viral sequences are more diverse in SVR patients than non-SVR patients receiving PEG-IFN/RBV therapy for genotype-2b HCV infection. Through systematic comparison of viral sequences, several specific regions, including part of the ISDR, were extracted as having significant correlation with the final outcome.


Assuntos
Antivirais/farmacologia , Hepacivirus/genética , Hepacivirus/patogenicidade , Interferon-alfa/farmacologia , Fases de Leitura Aberta/genética , Ribavirina/farmacologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Genótipo , Hepacivirus/classificação , Hepacivirus/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Filogenia , Proteínas Virais/genética , Proteínas Virais/metabolismo , Adulto Jovem
7.
Hepatol Int ; 5(3): 789-99, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21484117

RESUMO

PURPOSE: A proportion of patients infected with genotype 2a hepatitis C virus (HCV) cannot achieve a sustained virological response (SVR) to pegylated-interferon plus ribavirin therapy (PEG-IFN/RBV) but the reason remains unclear. The present study aimed to clarify the possible correlation between viral sequence variations and final outcome. METHODS: The pretreatment complete open reading frame (ORF) sequences of genotype 2a HCV were determined by direct sequencing for two independent groups of patients (43 patients as test; group 1 and 35 as validation; group 2), and the correlation with the final outcome was explored. RESULTS: Patients with SVR (n = 58) and with non-SVR (n = 20) differed significantly in pretreatment HCV RNA level (p = 0.002), fibrosis score (p = 0.047), and cumulative RBV dosage (p = 0.003). By comparison of all amino acid positions in the complete HCV ORFs, threonine at amino acid (aa) 110 in the core region was remarkably frequent in SVR (p = 0.01 for group 1, p = 0.004 for group 2, and p = 5E-05 for combined). A sliding window analysis revealed that the total number of amino acid variations within the NS5A aa 2258-2306 region were significantly high in SVR compared to non-SVR patients (p = 0.01 for group 1, p = 0.006 for group 2, and p = 0.0006 for combined). Multivariate analyses revealed that core aa 110 (p = 0.02), NS5A aa 2258-2306 (p = 0.03), and cumulative RBV dosage (p = 0.02) were identified as independent variables associated with the final outcome. CONCLUSIONS: The outcome of PEG-IFN/RBV therapy is significantly influenced by variation in the core and NS5A regions in genotype 2a HCV infection.

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