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1.
Clin Microbiol Infect ; 25(7): 906.e1-906.e7, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30472417

RESUMO

OBJECTIVE: We aimed to investigate HBx genetic elements correlated with hepatitis B virus (HBV) -related hepatocellular carcinoma (HCC) and their impact on (a) HBV replicative efficiency, (b) HBx binding to circular covalently closed DNA (cccDNA), (c) apoptosis and cell-cycle progression, and (d) HBx structural stability. METHODS: This study included 123 individuals chronically infected with HBV: 27 with HCC (77.9% (21/27) genotype D; 22.1% (6/27) genotype A) and 96 without HCC (75% (72/96) genotype D; 25.0% (24/96) genotype A). HepG2 cells were transfected by wild-type or mutated linear HBV genome to assess pre-genomic RNA (pgRNA) and core-associated HBV-DNA levels, HBx-binding onto cccDNA by chromatin immunoprecipitation-based quantitative assay, and rate of apoptosis and cell-cycle progression by cytofluorimetry. RESULTS: F30V was the only HBx mutation correlated with HCC (18.5% (5/27) in HCC patients versus 1.0% (1/96) in non-HCC patients, p 0.002); a result confirmed by multivariate analysis. In vitro, F30V determined a 40% and 60% reduction in pgRNA and core-associated HBV-DNA compared with wild-type (p <0.05), in parallel with a significant decrease of HBx binding to cccDNA and decreased HBx stability. F30V also decreased the percentage of apoptotic cells compared with wild-type (14.8 ± 6.8% versus 19.1 ± 10.1%, p <0.01, without affecting cell-cycle progression) and increased the probability of HBx-Ser-31 being phosphorylated by PI3K-Akt kinase (known to promote anti-apoptotic activity). CONCLUSIONS: F30V was closely correlated with HBV-induced HCC in vivo, reduced HBV replicative efficiency by affecting HBx-binding to cccDNA and increased anti-apoptotic HBx activity in vitro. This suggests that F30V (although hampering HBV's replicative capacity) may promote hepatocyte survival, so potentially allowing persistent production of viral progeny and initiating HBV-driven hepatocarcinogenesis. Investigation of viral genetic markers associated with HCC is crucial to identify those patients at higher risk of HCC, who hence deserve intensive liver monitoring and/or early anti-HBV therapy.


Assuntos
Apoptose , Carcinoma Hepatocelular/virologia , Vírus da Hepatite B/genética , Neoplasias Hepáticas/virologia , Transativadores/genética , Replicação Viral , Adulto , Idoso , DNA Viral/genética , Feminino , Genótipo , Células Hep G2 , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/virologia , Humanos , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Homologia Estrutural de Proteína , Transativadores/química , Proteínas Virais Reguladoras e Acessórias
2.
Clin Microbiol Infect ; 23(10): 777.e1-777.e4, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28412381

RESUMO

OBJECTIVES: First-generation protease-inhibitors (PIs) have suboptimal efficacy in GT-1 patients with advanced liver disease, and patients experiencing treatment failure may require urgent retreatment. Our objective was to analyse the real-life efficacy of interferon (IFN)-free retreatment after PI-failure, and the role of genotypic-resistance-testing (GRT) in guiding retreatment choice. METHODS: In this multi-centre observational study, patients retreated with IFN-free regimens after first-generation PI-failure (telaprevir-boceprevir-simeprevir) were included. Sustained-virological-response (SVR) was evaluated at week 12 of follow-up. GRT was performed by population-sequencing. RESULTS: After PI-failure, 121 patients (cirrhotic=86.8%) were retreated following three different strategies: A) with 'GRT-guided' regimens (N=18); B) with 'AASLD/EASL recommended, not GRT-guided' regimens (N=72); C) with 'not recommended, not GRT-guided' regimens (N=31). Overall SVR rate was 91%, but all 18 patients treated with 'GRT-guided' regimens reached SVR (100%), despite heterogeneity in treatment duration, use of PI and ribavirin, versus 68/72 patients (94.4%) receiving 'AASLD/EASL recommended, not GRT-guided' regimens. SVR was strongly reduced (77.4%) among the 31 patients who received a 'not recommended, not GRT-guided regimen' (p <0.01). Among 37 patients retreated with a PI, SVR rate was 89.2% (33/37). Four GT-1a cirrhotic patients failed an option (C) simeprevir-containing treatment; three out of four had a baseline R155K NS3-RAS. All seven patients treated with paritaprevir-containing regimens reached SVR, regardless of treatment duration and performance of a baseline-GRT. CONCLUSION: Retreatment of PI-experienced patients can induce maximal SVR rates in real life. Baseline-GRT could help to optimize retreatment strategy, allowing PIs to be reconsidered when chosen after a RASs evaluation.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Inibidores de Proteases/uso terapêutico , Adulto , Idoso , Feminino , Técnicas de Genotipagem , Hepacivirus/genética , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Retratamento , Análise de Sequência de DNA , Resposta Viral Sustentada , Falha de Tratamento
3.
J Antimicrob Chemother ; 71(3): 739-50, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26679249

RESUMO

OBJECTIVES: This study aims to evaluate the reliability and clinical utility of NS3 sequencing in hepatitis C virus (HCV) 1-infected patients who were candidates to start a PI-containing regimen. METHODS: NS3 protease sequencing was performed by in-house-developed HCV-1 subtype-specific protocols. Phylogenetic analysis was used to test sequencing reliability and concordance with previous genotype/subtype assignment by commercial genotyping assays. RESULTS: Five hundred and sixty-seven HCV plasma samples with quantifiable HCV-RNA from 326 HCV-infected patients were collected between 2011 and 2014. Overall, the success rate of NS3 sequencing was 88.9%. The success rate between the two subtype protocols (HCV-1a/HCV-1b) was similarly high for samples with HCV-RNA >3 log IU/mL (>92% success rate), while it was slightly lower for HCV-1a samples with HCV-RNA ≤3 log IU/mL compared with HCV-1b samples. Phylogenetic analysis confirmed the genotype/subtype given by commercial genotyping assays in 92.9% (303/326) of cases analysed. In the remaining 23 cases (7.1%), 1 was HCV-1g (previously defined as subtype 1a), 1 was HCV-4d (previously defined as genotype 1b) and 1 was HCV-1b (previously defined as genotype 2a/2c). In the other cases, NS3 sequencing precisely resolved the either previous undetermined/discordant subtype 1 or double genotype/subtype assignment by commercial genotyping assays. Resistance-associated variants (RAVs) to PI were detected in 31.0% of samples. This prevalence changed according to PI experience (17.1% in PI-naive patients versus 79.2% in boceprevir/telaprevir/simeprevir-failing patients). Among 96 patients with available virological outcome following boceprevir/telaprevir treatment, a trend of association between baseline NS3 RAVs and virological failure was observed (particularly for HCV-1a-infected patients: 3/21 failing patients versus 0/22 achieving sustained virological response; P = 0.11). CONCLUSIONS: HCV-NS3 sequencing provides reliable results and at the same time gives two clinically relevant pieces of information: a correct subtype/genotype assignment and the detection of variants that may interfere with the efficacy of PI.


Assuntos
Farmacorresistência Viral , Técnicas de Genotipagem/métodos , Hepacivirus/classificação , Hepacivirus/efeitos dos fármacos , Hepatite C/virologia , Mutação , Proteínas não Estruturais Virais/genética , Genótipo , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Humanos , RNA Viral/genética , Estudos Retrospectivos , Análise de Sequência de DNA
4.
J Viral Hepat ; 13(12): 821-7, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17109681

RESUMO

The alpha-defensin genes promoter regions contain a putative nuclear factors of activated T cells (NFAT)-binding site and it is known that hepatitis C virus (HCV) core protein activates the interleukin (IL)-2 gene transcription through the NFAT pathway. The aims of this study were to investigate if HCV affects the alpha-defensin expression in peripheral human mononuclear cells (PBMCs) and to evaluate the existence of a correlation between alpha-defensins and liver damage in patients with chronic hepatitis C. Ninety patients with chronic hepatitis C, 30 with chronic hepatitis B and 25 healthy controls were enrolled. Alpha-defensins were identified and quantified in PBMCs by mass spectrometry, enzyme-linked immunosorbent assay, antibacterial activity and mRNA levels. PBMCs from three patients and controls were stimulated with HCV core protein, hepatitis B virus core antigen and the alpha-defensin mRNAs level was quantified. We found that HCV core protein activates in vitro the alpha-defensin transcription. Alpha-defensin levels in patients with chronic hepatitis C (mean +/- SD = 1.103 +/- 0.765 ng/10(6) cells), chronic hepatitis B (0.53 +/- 0.15) and healthy controls (0.217 +/- 0.09) resulted significantly different (P < 0.001). In patients with chronic hepatitis C, the alpha-defensin levels and antibacterial activity correlate with the liver fibrosis. Our data suggest that HCV induces alpha-defensin expression. The high linear correlation of alpha-defensin levels with advancing fibrosis makes the measure of these peptides a reliable marker to evaluate fibrosis stage.


Assuntos
Anti-Infecciosos/imunologia , Hepatite C Crônica/imunologia , Leucócitos Mononucleares/imunologia , alfa-Defensinas/sangue , Adulto , Anti-Infecciosos/metabolismo , Feminino , Expressão Gênica , Hepatite C Crônica/sangue , Hepatite C Crônica/patologia , Hepatite C Crônica/virologia , Humanos , Cirrose Hepática/sangue , Cirrose Hepática/imunologia , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Regiões Promotoras Genéticas , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , alfa-Defensinas/biossíntese , alfa-Defensinas/genética , alfa-Defensinas/imunologia
5.
J Viral Hepat ; 8(4): 284-6, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11454180

RESUMO

The optimal therapy for patients with chronic hepatitis C who have not responded to interferon (IFN) is still an unsolved issue. The aim of this study was to evaluate the efficacy and tolerability of a high dose of IFN-alpha2a plus amantadine for chronic hepatitis C patients who were non-responders to a previous course of IFN. Forty consecutive patients with chronic hepatitis C, genotype 1b, who had not responded to IFN-alpha, were randomized to receive: (i) IFN 4.5 MU daily plus amantadine 200 mg/day for 4 weeks and then IFN 6 MU thrice weekly plus amantadine 200 mg/day for an additional 5 months (group A) or (ii) IFN alone at the same dosage and duration (group B). After 1 month of therapy, normal alanine aminotransferase (ALT) values were observed in three of 21 (14.3%) patients in group A and in three of 19 (15.8%) in group B; serum hepatitis C virus (HCV)-RNA clearance was observed in one patient (4.8%) in group A and in six (31.6%) in group B. At the end of treatment, six patients (28.6%) in group A and three (15.8%) in group B had normal ALT levels; however, HCV-RNA in serum was detectable in all of them at levels comparable to the basal values; an ALT relapse occurred within 3 months of stopping therapy. The combination of daily IFN plus amantadine was ineffective in this setting.


Assuntos
Amantadina/uso terapêutico , Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Resistência Microbiana a Medicamentos , Quimioterapia Combinada , Feminino , Seguimentos , Hepatite C Crônica/sangue , Hepatite C Crônica/metabolismo , Humanos , Interferon-alfa/sangue , Masculino , Projetos Piloto
6.
J Viral Hepat ; 7(3): 184-95, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10849260

RESUMO

We conducted an analytical review of 194 full papers on interferon (IFN) therapy for chronic hepatitis C to evaluate current methodology (i.e. study design, criteria for evaluating the efficacy of therapy and predictors of response). Of the papers evaluated, 64 were randomized controlled trials (RCT), 40 were non-randomized controlled trials (NRCT) and 90 were observational studies (OS). The methodological analysis was focused mainly on clinical trials. The number of patients enrolled in RCT was higher compared with the number enrolled in NRCT. Uniform enrolment criteria were used in less than 50% of the trials. Only 20% of RCT and 2.5% of NRCT used criteria for defining sample size. The response rate was calculated on an intention-to-treat basis in 36 of the RCT and in 14 of the NRCT. The outcome of treatment and the criteria employed to define the response to treatment were found to be far from standardized. In 51.5% of the RCT and 42.5% of the NRCT, normalization of alanine aminotransferase (ALT) level at the end of follow-up was the only marker of response studied. Only 57.6% of the trials considered histological evidence as an important outcome. Among the clinical trials, 71.1% evaluated predictors of good response to IFN therapy. In 51% of the OS, ALT normalization by the end of follow-up was the only criterion for defining response. In conclusion, to ensure a high level of reliability in comparing or combining the results of different studies, some basic general requirements must be followed when planning trials on antiviral therapy.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interferons/uso terapêutico , Ensaios Clínicos como Assunto/normas , Hepatite C Crônica/virologia , Humanos , Metanálise como Assunto , Projetos de Pesquisa , Resultado do Tratamento , Viremia
8.
Res Virol ; 148(2): 139-42, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9108615

RESUMO

In order to improve our knowledge of the incidence of liver cirrhosis in Italy, we conducted two epidemiological studies. The first study showed that about 15% of asymptomatic subjects with persistent increase in alanine aminotransferase had histological evidence of cirrhosis. In this setting, cirrhosis was associated with viral aetiology in 91.4% of cases. In the second study, which enrolled cirrhosis patients from 13 centres from all regions of the country, viral infections were detected in 82.6% of patients, the large majority of whom, 71.2%, were positive for hepatitis C virus (HCV). Alcohol abuse was present in 8.7% of cases as exclusive aetiological factor. All the patients were classified according to Child-Pugh and were scored as class A in 62.4%, as class B in 23.8% and as class C in 13.8% of cases. The age distribution showed that about 55% of cirrhosis patients were under 60 years of age; 34.3% of them had a Child-Pugh score of class B or C. These data show that HCV infection represents the predominant aetiological factor of cirrhosis in Italy and that cirrhosis can be found frequently in asymptomatic subjects.


Assuntos
Cirrose Hepática/epidemiologia , Alcoolismo/complicações , Feminino , Hepacivirus/isolamento & purificação , Hepatite C/complicações , Humanos , Itália/epidemiologia , Cirrose Hepática/virologia , Masculino
9.
Arch Virol ; 142(3): 557-65, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9349301

RESUMO

Serum levels of soluble intercellular adhesion molecule-1 (sICAM-1) have been examined in 38 patients with chronic hepatitis C liver disease treated with interferon. The sICAM-1 values were found to correlate significantly with the ALT values. Pre-treatment sICAM-1 values of responder and nonresponder patients were not significantly different while, by the end of the treatment, the values of responders were significantly lower compared to those of nonresponders. However, no difference could be found between sustained and relapse responders. Of the 21 patients examined for PBMC HCV-RNA, 15 (71.4%) were found to be positive. Neither the rate of responsivity to interferon treatment, nor the mean sICAM-1 values correlated with the positivity of PBMC HCV-RNA. However, the clearance of serum and PBMC HCV-RNA was associated to a significant decrease of sICAM-1 and ALT levels. In conclusion, sICAM-1 values were found to correlate with ongoing viral replication and liver cytonecrosis, but were not influenced by the concomitant HCV infection of PBMC.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/terapia , Molécula 1 de Adesão Intercelular/sangue , Interferon-alfa/uso terapêutico , Leucócitos Mononucleares/virologia , Adulto , Idoso , Alanina Transaminase/metabolismo , Feminino , Seguimentos , Hepatite C Crônica/sangue , Hepatite C Crônica/virologia , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , RNA Viral , Proteínas Recombinantes , Solubilidade
10.
J Med Virol ; 47(1): 16-22, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8551253

RESUMO

The polymerase chain reaction (PCR) was used to investigate the presence of positive and negative hepatitis C virus (HCV) RNA strands in serum and peripheral blood mononuclear cells (PBMC) of 20 patients with histologically proven HCV-related chronic liver disease. All patients completed a course of interferon (IFN) treatment (6 MU of IFN-alpha 2b three times a week for 24 weeks) and were followed-up for 12 months after treatment was discontinued. Pre-treatment, end-treatment and 6-month follow-up serum and PBMC samples were examined. At enrollment, the positive strand of HCV-RNA was detected in serum of 18 patients (90%), the negative strand in none. Positive-stranded HCV-RNA was detected in PBMC of 15 patients (75%), 13 of whom also had detectable levels of negative-stranded HCV-RNA in PBMC. By the end of the treatment, 12 patients (60%) were responders. The pre-treatment HCV infection of PBMC, indicated by the presence of both RNA strands, was found in 8 (66.7%) responders compared to 5 (62.5%) non-responders (P = n.s.). End-treatment loss of PBMC HCV-RNA correlated significantly with the response since it occurred in all responders compared to 2 non-responders (P = 0.02). However, end-treatment-negative serum and PBMC HCV-RNA did not predict the occurrence of a sustained response, which was observed at month 12 in 5 of 12 responders (P = n.s.). On the other hand, the persistent absence of HCV RNA in serum and PBMC at the end of the 6-month follow-up was significantly associated with the occurrence of a sustained response (P < 0.0001).


Assuntos
Hepacivirus/isolamento & purificação , Hepatite C/virologia , Interferon-alfa/uso terapêutico , Leucócitos Mononucleares/virologia , RNA Viral/sangue , Adulto , Idoso , Sequência de Bases , Doença Crônica , Primers do DNA , Feminino , Seguimentos , Hepacivirus/genética , Hepatite C/terapia , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Proteínas Recombinantes , Resultado do Tratamento
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