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1.
Hepatology ; 55(4): 1038-47, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22095909

RESUMEN

UNLABELLED: Elevated serum ferritin levels may reflect a systemic inflammatory state as well as increased iron storage, both of which may contribute to an unfavorable outcome of chronic hepatitis C (CHC). We therefore performed a comprehensive analysis of the role of serum ferritin and its genetic determinants in the pathogenesis and treatment of CHC. To this end, serum ferritin levels at baseline of therapy with pegylated interferon-alpha and ribavirin or before biopsy were correlated with clinical and histological features of chronic hepatitis C virus (HCV) infection, including necroinflammatory activity (N = 970), fibrosis (N = 980), steatosis (N = 886), and response to treatment (N = 876). The association between high serum ferritin levels (> median) and the endpoints was assessed by logistic regression. Moreover, a candidate gene as well as a genome-wide association study of serum ferritin were performed. We found that serum ferritin ≥ the sex-specific median was one of the strongest pretreatment predictors of treatment failure (univariate P < 0.0001, odds ratio [OR] = 0.45, 95% confidence interval [CI] = 0.34-0.60). This association remained highly significant in a multivariate analysis (P = 0.0002, OR = 0.35, 95% CI = 0.20-0.61), with an OR comparable to that of interleukin (IL)28B genotype. When patients with the unfavorable IL28B genotypes were stratified according to high versus low ferritin levels, SVR rates differed by > 30% in both HCV genotype 1- and genotype 3-infected patients (P < 0.001). Serum ferritin levels were also independently associated with severe liver fibrosis (P < 0.0001, OR = 2.67, 95% CI = 1.68-4.25) and steatosis (P = 0.002, OR = 2.29, 95% CI = 1.35-3.91), but not with necroinflammatory activity (P = 0.3). Genetic variations had only a limited impact on serum ferritin levels. CONCLUSION: In patients with CHC, elevated serum ferritin levels are independently associated with advanced liver fibrosis, hepatic steatosis, and poor response to interferon-alpha-based therapy.


Asunto(s)
Ferritinas/sangre , Hepatitis C Crónica/sangre , Hepatitis C Crónica/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Fenotipo , Polietilenglicoles/uso terapéutico , Ribavirina/uso terapéutico , Adolescente , Adulto , Anciano , Antivirales/uso terapéutico , Biomarcadores/sangre , Quimioterapia Combinada , Hígado Graso/epidemiología , Femenino , Genotipo , Hepacivirus/genética , Hepatitis C Crónica/complicaciones , Humanos , Incidencia , Cirrosis Hepática/epidemiología , Masculino , Persona de Mediana Edad , Proteínas Recombinantes/uso terapéutico , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento , Adulto Joven
2.
Gastroenterology ; 140(3): 1021-31, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21111740

RESUMEN

BACKGROUND & AIMS: The host immune response during the chronic phase of hepatitis C virus infection varies among individuals; some patients have a no interferon (IFN) response in the liver, whereas others have full activation of IFN-stimulated genes (ISGs). Preactivation of this endogenous IFN system is associated with nonresponse to pegylated IFN-α (pegIFN-α) and ribavirin. Genome-wide association studies have associated allelic variants near the IL28B (IFNλ3) gene with treatment response. We investigated whether IL28B genotype determines the constitutive expression of ISGs in the liver and compared the abilities of ISG levels and IL28B genotype to predict treatment outcome. METHODS: We genotyped 109 patients with chronic hepatitis C for IL28B allelic variants and quantified the hepatic expression of ISGs and of IL28B. Decision tree ensembles, in the form of a random forest classifier, were used to calculate the relative predictive power of these different variables in a multivariate analysis. RESULTS: The minor IL28B allele was significantly associated with increased expression of ISG. However, stratification of the patients according to treatment response revealed increased ISG expression in nonresponders, irrespective of IL28B genotype. Multivariate analysis of ISG expression, IL28B genotype, and several other factors associated with response to therapy identified ISG expression as the best predictor of treatment response. CONCLUSIONS: IL28B genotype and hepatic expression of ISGs are independent predictors of response to treatment with pegIFN-α and ribavirin in patients with chronic hepatitis C. The most accurate prediction of response was obtained with a 4-gene classifier comprising IFI27, ISG15, RSAD2, and HTATIP2.


Asunto(s)
Antivirales/uso terapéutico , Regulación de la Expresión Génica/efectos de los fármacos , Hepatitis C Crónica/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Interleucinas/genética , Hígado/efectos de los fármacos , Polietilenglicoles/uso terapéutico , Ribavirina/uso terapéutico , Acetiltransferasas/genética , Adulto , Biopsia , Citocinas/genética , Técnicas de Apoyo para la Decisión , Árboles de Decisión , Quimioterapia Combinada , Femenino , Genotipo , Hepatitis C Crónica/diagnóstico , Hepatitis C Crónica/genética , Hepatitis C Crónica/inmunología , Humanos , Interferón alfa-2 , Interferones , Hígado/inmunología , Hígado/metabolismo , Hígado/virología , Modelos Logísticos , Masculino , Proteínas de la Membrana/genética , Persona de Mediana Edad , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH , Fenotipo , Proteínas/genética , ARN Mensajero/metabolismo , Proteínas Recombinantes , Medición de Riesgo , Factores de Riesgo , Suiza , Factores de Transcripción/genética , Resultado del Tratamiento , Ubiquitinas/genética
3.
J Hepatol ; 55(2): 322-7, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21147186

RESUMEN

BACKGROUND & AIMS: Recent studies have described a major impact of genetic variations near the IL28B gene on the natural course and outcome of antiviral therapy in chronic hepatitis C. We therefore, aimed to explore the impact of donor and recipient genotypes of these polymorphisms on hepatitis C virus (HCV) liver graft reinfection. METHODS: Donor and recipient genotypes of IL28B rs12979860C>T single nucleotide polymorphism were determined in 91 patients with HCV liver graft reinfection, 47 of whom were treated with pegylated interferon-α (PEG-IFN-α) and ribavirin. IL28B genetic polymorphisms were correlated with the natural course and treatment outcome of recurrent hepatitis C. RESULTS: Patients requiring liver transplantation due to end-stage chronic hepatitis C appeared to be selected toward the adverse genotypes rs12979860 CT/TT compared to non-transplanted HCV-infected patients (p=0.046). Patients with the donor genotype rs12979860 CC had higher peak ALT and HCV RNA serum concentrations than those with CT/TT (p=0.04 and 0.06, respectively). No association was observed between ALT/HCV RNA serum concentrations and recipient genotypes (p>0.3). More important, donor IL28B rs12979860 CC vs. CT/TT genotypes were associated with rapid, complete early, and sustained virologic response (RVR, cEVR, SVR) to treatment with PEG-IFN-α and ribavirin (p=0.003, 0.0012, 0.008, respectively), but weaker associations of recipient genotypes with RVR, cEVR, and SVR were observed as well (p=0.0046, 0.115, 0.118, respectively). CONCLUSIONS: We provide evidence for a dominant, but not exclusive impact of the donor rather than the recipient IL28B genetic background on the natural course and treatment outcome of HCV liver graft reinfection.


Asunto(s)
Hepatitis C Crónica/genética , Hepatitis C Crónica/cirugía , Interleucinas/genética , Trasplante de Hígado/efectos adversos , Adulto , Anciano , Alanina Transaminasa/sangre , Antivirales/administración & dosificación , Femenino , Genotipo , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C Crónica/fisiopatología , Humanos , Interferón alfa-2 , Interferón-alfa/administración & dosificación , Interferones , Cirrosis Hepática/etiología , Trasplante de Hígado/fisiología , Masculino , Persona de Mediana Edad , Polietilenglicoles/administración & dosificación , Polimorfismo de Nucleótido Simple , ARN Viral/sangre , Proteínas Recombinantes/administración & dosificación , Recurrencia , Ribavirina/administración & dosificación , Donantes de Tejidos , Resultado del Tratamiento
4.
Gastroenterology ; 138(4): 1338-45, 1345.e1-7, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20060832

RESUMEN

BACKGROUND & AIMS: Hepatitis C virus (HCV) induces chronic infection in 50% to 80% of infected persons; approximately 50% of these do not respond to therapy. We performed a genome-wide association study to screen for host genetic determinants of HCV persistence and response to therapy. METHODS: The analysis included 1362 individuals: 1015 with chronic hepatitis C and 347 who spontaneously cleared the virus (448 were coinfected with human immunodeficiency virus [HIV]). Responses to pegylated interferon alfa and ribavirin were assessed in 465 individuals. Associations between more than 500,000 single nucleotide polymorphisms (SNPs) and outcomes were assessed by multivariate logistic regression. RESULTS: Chronic hepatitis C was associated with SNPs in the IL28B locus, which encodes the antiviral cytokine interferon lambda. The rs8099917 minor allele was associated with progression to chronic HCV infection (odds ratio [OR], 2.31; 95% confidence interval [CI], 1.74-3.06; P = 6.07 x 10(-9)). The association was observed in HCV mono-infected (OR, 2.49; 95% CI, 1.64-3.79; P = 1.96 x 10(-5)) and HCV/HIV coinfected individuals (OR, 2.16; 95% CI, 1.47-3.18; P = 8.24 x 10(-5)). rs8099917 was also associated with failure to respond to therapy (OR, 5.19; 95% CI, 2.90-9.30; P = 3.11 x 10(-8)), with the strongest effects in patients with HCV genotype 1 or 4. This risk allele was identified in 24% of individuals with spontaneous HCV clearance, 32% of chronically infected patients who responded to therapy, and 58% who did not respond (P = 3.2 x 10(-10)). Resequencing of IL28B identified distinct haplotypes that were associated with the clinical phenotype. CONCLUSIONS: The association of the IL28B locus with natural and treatment-associated control of HCV indicates the importance of innate immunity and interferon lambda in the pathogenesis of HCV infection.


Asunto(s)
Estudio de Asociación del Genoma Completo , Hepatitis C Crónica/genética , Interleucinas/genética , Polimorfismo de Nucleótido Simple , Adulto , Anciano , Femenino , Variación Genética , Genotipo , Haplotipos , Hepatitis C Crónica/tratamiento farmacológico , Humanos , Interferón alfa-2 , Interferón-alfa/administración & dosificación , Interferones , Masculino , Persona de Mediana Edad , Polietilenglicoles/administración & dosificación , Proteínas Recombinantes , Ribavirina/administración & dosificación , Insuficiencia del Tratamiento
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