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1.
J Virol ; 88(11): 6394-402, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24672032

RESUMO

UNLABELLED: The microRNA miR-122 is highly expressed in the liver and stimulates hepatitis C virus (HCV) replication in vitro. IFNL3 (lambda-3 interferon gene) polymorphisms and the expression of miR-122 have been associated with sustained virological response (SVR) to treatment with pegylated interferon plus ribavirin in patients with chronic hepatitis C (CHC). We investigated, in vivo, the relationship between miR-122 expression, IFNL3 polymorphism, fibrosis, and response to PEG-IFN plus ribavirin. Pretreatment liver biopsy specimens and serum samples from 133 patients with CHC were included. Sixty-six patients achieved SVR, and 64 failed to respond to the treatment (43 nonresponders [NR] and 21 relapsers [RR]). All stages of fibrosis were represented, with 39, 50, 23, and 19 patients, respectively, having Metavir scores of F1, F2, F3, and F4. miR-122 expression was assessed by real-time quantitative PCR (RT-qPCR) and IFNL3 rs12979860 by direct sequencing. Hepatic miR-122 expression was higher in patients with the IFNL3 CC genotype than in those with the IFNL3 CT or TT genotype, in all patients (P = 0.025), and in NRs plus RRs (P = 0.013). Increased hepatic miR-122 was more strongly associated with complete early virological response (cEVR) (P = 0.003) than with SVR (P = 0.016). In multivariate analysis, increased hepatic miR-122 was only associated with the IFNL3 CC genotype. miR-122 was decreased in patients with advanced fibrosis (Metavir scores of F3 and F4) compared to its levels in patients with mild and moderate fibrosis (F1 and F2) (P = 0.01). Serum and hepatic expression of miR-122 were not associated. The association between miR-122 and IFNL3 was stronger than the association between miR-122 and response to treatment. miR-122 may play a role in the early viral decline that is dependent on IFNL3 and the innate immune response. IMPORTANCE: miR-122 plays a crucial role during HCV infection. Moreover, it was reported that miR-122 binding within the HCV genome stimulates its replication. Moreover, miR-122 is highly expressed within hepatocytes, where it regulates many cellular pathways. A reduction of miR-122 expression has been suggested to be associated with responsiveness to IFN-based therapy in patients with chronic hepatitis C. Several independent genome-wide association studies reported a strong association between IFNL3 polymorphism and responsiveness to IFN-based therapy. We report here a strong association between the expression of miR-122 and IFNL3 polymorphism that is independent of the response to the treatment. Our data suggest that modification of miR-122 expression may play an important role in the molecular mechanism associated with IFNL3 polymorphism. Moreover, we report a reduction of miR-122 at more advanced stages of fibrosis in patients with chronic hepatitis C.


Assuntos
Regulação da Expressão Gênica/genética , Hepatite C Crônica/complicações , Interleucinas/genética , Cirrose Hepática/metabolismo , MicroRNAs/metabolismo , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Quimioterapia Combinada , Genótipo , Hepatite C Crônica/tratamento farmacológico , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Interferons , Modelos Lineares , Cirrose Hepática/etiologia , Polietilenoglicóis/uso terapêutico , Polimorfismo de Nucleotídeo Único/genética , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Recombinantes/uso terapêutico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ribavirina/uso terapêutico , Estatísticas não Paramétricas , Carga Viral
2.
Antimicrob Agents Chemother ; 58(9): 5332-41, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24982076

RESUMO

Triple therapy combining a protease inhibitor (PI) (telaprevir or boceprevir), pegylated interferon (PEG-IFN), and ribavirin (RBV) has dramatically increased the chance of eradicating hepatitis C virus (HCV). However, the efficacy of this treatment remains suboptimal in cirrhotic treatment-experienced patients. Here, we aimed to better understand the origin of this impaired response by estimating the antiviral effectiveness of each drug. Fifteen HCV genotype 1-infected patients with compensated cirrhosis, who were nonresponders to prior PEG-IFN/RBV therapy, were enrolled in a nonrandomized study. HCV RNA and concentrations of PIs, PEG-IFN, and RBV were frequently assessed in the first 12 weeks of treatment and were analyzed using a pharmacokinetic/viral kinetic model. The two PIs achieved similar levels of molar concentrations (P=0.5), but there was a significant difference in the 50% effective concentrations (EC50) (P=0.008), leading to greater effectiveness for telaprevir than for boceprevir in blocking viral production (99.8% versus 99.0%, respectively, P=0.002). In all patients, the antiviral effectiveness of PEG-IFN was modest (43.4%), and there was no significant contribution of RBV exposure to the total antiviral effectiveness. The second phase of viral decline, which is attributed to the loss rate of infected cells, was slow (0.19 day(-1)) and was higher in patients who subsequently eradicated HCV (P=0.03). The two PIs achieved high levels of antiviral effectiveness. However, the suboptimal antiviral effectiveness of PEG-IFN/RBV and the low loss of infected cells suggest that a longer treatment duration might be needed in cirrhotic treatment-experienced patients and that a future IFN-free regimen may be particularly beneficial in these patients.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/efeitos dos fármacos , Hepatite C/tratamento farmacológico , Interferon-alfa/uso terapêutico , Oligopeptídeos/uso terapêutico , Polietilenoglicóis/uso terapêutico , Prolina/análogos & derivados , Adulto , Antivirais/farmacocinética , Antivirais/farmacologia , Quimioterapia Combinada , Feminino , Humanos , Interferon-alfa/administração & dosagem , Interferon-alfa/farmacocinética , Interferon-alfa/farmacologia , Cinética , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Oligopeptídeos/administração & dosagem , Oligopeptídeos/farmacocinética , Oligopeptídeos/farmacologia , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/farmacocinética , Polietilenoglicóis/farmacologia , Prolina/administração & dosagem , Prolina/farmacocinética , Prolina/farmacologia , Prolina/uso terapêutico , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacocinética , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Resultado do Tratamento
3.
Hepatology ; 49(4): 1151-7, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19115222

RESUMO

UNLABELLED: Pegylated interferon alfa-2a (PEG-IFN) may induce sustained virological response (SVR) in 20% of hepatitis B e antigen (HBeAg)-negative chronic hepatitis B (CHB) patients. In addition, loss of hepatitis B surface antigen (HBsAg) is achieved with a 10% yearly rate after treatment cessation in sustained responders. The aim of this study was to assess on-treatment serum HBsAg kinetics to predict SVR in HBeAg-negative patients treated with PEG-IFN. Forty-eight consecutive patients were treated with PEG-IFN (180 microg/week) for 48 weeks. Serum hepatitis B virus (HBV) DNA (COBAS TaqMan) and HBsAg (Abbott Architect HBsAg QT assay) were assessed at baseline, during treatment (weeks 12, 24, and 48), and during follow-up (weeks 72 and 96). SVR was defined as undetectable serum HBV DNA (<70 copies/mL) 24 weeks after treatment cessation. Twenty-five percent of patients achieved SVR. They were not different from those who failed treatment regarding age, sex, ethnicity, HBV genotype, baseline serum HBV DNA and HBsAg levels, or liver histology. During treatment, serum HBsAg levels decreased only in patients who developed SVR, with mean decreases of 0.8 +/- 0.5, 1.5 +/- 0.6, and 2.1 +/- 1.2 log(10) IU/mL at weeks 12, 24, and 48, respectively. A decrease of 0.5 and 1 log(10) IU/mL in serum HBsAg levels at weeks 12 and 24 of therapy, respectively, had high predictive values of SVR (negative predictive value [NPV] 90%, positive predictive value [PPV] 89% for week 12; NPV 97%, PPV 92% for week 24). HBsAg loss was observed in three patients, all with SVR. CONCLUSION: Early serum HBsAg drop has high predictive values of SVR to PEG-IFN in HBeAg-negative CHB patients. Serum quantitative HBsAg may be a useful tool to optimize the management of PEG-IFN therapy in these patients.


Assuntos
Antivirais/uso terapêutico , DNA Viral/sangue , Antígenos de Superfície da Hepatite B/sangue , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Adulto , Feminino , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/imunologia , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Proteínas Recombinantes
4.
Clin Liver Dis ; 11(4): 839-49, viii, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17981231

RESUMO

This article summarizes the results obtained with interferon alfa and pegylated interferon alfa, as monotherapy and in combination with lamivudine, in the treatment of chronic hepatitis B.


Assuntos
Antivirais/farmacologia , Vírus da Hepatite B/crescimento & desenvolvimento , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/farmacologia , Antivirais/uso terapêutico , Quimioterapia Combinada , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Polietilenoglicóis , Proteínas Recombinantes
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