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1.
J Hepatol ; 73(3): 549-558, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32294532

RESUMO

BACKGROUND & AIMS: HCV is a positive-strand RNA virus that primarily infects human hepatocytes. Recent studies have reported that C19orf66 is expressed as an interferon (IFN)-stimulated gene; however, the intrinsic regulation of this gene within the liver as well as its antiviral effects against HCV remain elusive. METHODS: Expression of C19orf66 was quantified in both liver biopsies and primary human hepatocytes, with or without HCV infection. Mechanistic studies of the potent anti-HCV phenotype mediated by C19orf66 were conducted using state-of-the-art virological, biochemical and genetic approaches, as well as correlative light and electron microscopy and transcriptome and proteome analysis. RESULTS: Upregulation of C19orf66 mRNA was observed in both primary human hepatocytes upon HCV infection and in the livers of patients with chronic hepatitis C (CHC). In addition, pegIFNα/ribavirin therapy induced C19orf66 expression in patients with CHC. Transcriptomic profiling and whole cell proteomics of hepatoma cells ectopically expressing C19orf66 revealed no induction of other antiviral genes. Expression of C19orf66 restricted HCV infection, whereas CRIPSPR/Cas9 mediated knockout of C19orf66 attenuated IFN-mediated suppression of HCV replication. Co-immunoprecipitation followed by mass spectrometry identified a stress granule protein-dominated interactome of C19orf66. Studies with subgenomic HCV replicons and an expression system revealed that C19orf66 expression impairs HCV-induced elevation of phosphatidylinositol-4-phosphate, alters the morphology of the viral replication organelle (termed the membranous web) and thereby targets viral RNA replication. CONCLUSION: C19orf66 is an IFN-stimulated gene, which is upregulated in hepatocytes within the first hours post IFN treatment or HCV infection in vivo. The encoded protein possesses specific antiviral activity against HCV and targets the formation of the membranous web. Our study identifies C19orf66 as an IFN-inducible restriction factor with a novel antiviral mechanism that specifically targets HCV replication. LAY SUMMARY: Interferon-stimulated genes are thought to be important to for antiviral immune responses to HCV. Herein, we analysed C19orf66, an interferon-stimulated gene, which appears to inhibit HCV replication. It prevents the HCV-induced elevation of phosphatidylinositol-4-phosphate and alters the morphology of HCV's replication organelle.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/metabolismo , Interferons/uso terapêutico , Organelas/virologia , Proteínas de Ligação a RNA/metabolismo , Compartimentos de Replicação Viral/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Adulto , Linhagem Celular Tumoral , Feminino , Técnicas de Inativação de Genes , Genótipo , Células HEK293 , Hepatite C Crônica/patologia , Hepatite C Crônica/virologia , Hepatócitos/metabolismo , Humanos , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Organelas/efeitos dos fármacos , Organelas/metabolismo , RNA Viral/metabolismo , Proteínas de Ligação a RNA/genética , Replicon/efeitos dos fármacos , Replicon/genética , Ribavirina/uso terapêutico , Resultado do Tratamento , Replicação Viral/genética
2.
Gastroenterology ; 156(8): 2313-2329.e7, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30836093

RESUMO

BACKGROUND & AIMS: Chronic hepatitis C virus (HCV) infection is an important risk factor for hepatocellular carcinoma (HCC). Despite effective antiviral therapies, the risk for HCC is decreased but not eliminated after a sustained virologic response (SVR) to direct-acting antiviral (DAA) agents, and the risk is higher in patients with advanced fibrosis. We investigated HCV-induced epigenetic alterations that might affect risk for HCC after DAA treatment in patients and mice with humanized livers. METHODS: We performed genome-wide ChIPmentation-based ChIP-Seq and RNA-seq analyses of liver tissues from 6 patients without HCV infection (controls), 18 patients with chronic HCV infection, 8 patients with chronic HCV infection cured by DAA treatment, 13 patients with chronic HCV infection cured by interferon therapy, 4 patients with chronic hepatitis B virus infection, and 7 patients with nonalcoholic steatohepatitis in Europe and Japan. HCV-induced epigenetic modifications were mapped by comparative analyses with modifications associated with other liver disease etiologies. uPA/SCID mice were engrafted with human hepatocytes to create mice with humanized livers and given injections of HCV-infected serum samples from patients; mice were given DAAs to eradicate the virus. Pathways associated with HCC risk were identified by integrative pathway analyses and validated in analyses of paired HCC tissues from 8 patients with an SVR to DAA treatment of HCV infection. RESULTS: We found chronic HCV infection to induce specific genome-wide changes in H3K27ac, which correlated with changes in expression of mRNAs and proteins. These changes persisted after an SVR to DAAs or interferon-based therapies. Integrative pathway analyses of liver tissues from patients and mice with humanized livers demonstrated that HCV-induced epigenetic alterations were associated with liver cancer risk. Computational analyses associated increased expression of SPHK1 with HCC risk. We validated these findings in an independent cohort of patients with HCV-related cirrhosis (n = 216), a subset of which (n = 21) achieved viral clearance. CONCLUSIONS: In an analysis of liver tissues from patients with and without an SVR to DAA therapy, we identified epigenetic and gene expression alterations associated with risk for HCC. These alterations might be targeted to prevent liver cancer in patients treated for HCV infection.


Assuntos
Antivirais/uso terapêutico , Carcinoma Hepatocelular/virologia , Hepatite C Crônica/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/virologia , Adulto , Animais , Carcinoma Hepatocelular/genética , Estudos de Casos e Controles , Estudos de Coortes , Modelos Animais de Doenças , Epigênese Genética , Europa (Continente) , Feminino , Regulação Neoplásica da Expressão Gênica , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Humanos , Japão , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos SCID , Distribuição Aleatória , Resposta Viral Sustentada
3.
Gastroenterology ; 154(6): 1778-1790, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29408639

RESUMO

BACKGROUND & AIMS: Most viruses are detected at early stages of cell infection and induce an innate immune response mediated by production of interferons (IFNs). IFNs induce expression of hundreds of IFN-stimulated genes (ISGs). Infection of chimpanzees with hepatitis C virus, but not hepatitis B virus (HBV), induces ISG expression in the liver. HBV might not induce an innate immune response because it is not detected by pattern recognition receptors (the stealth properties of HBV) or because HBV suppresses IFN production or signaling despite detection by pattern recognition receptors. We studied innate immune signaling in liver biopsies from patients with different stages of chronic HBV infection and uninfected individuals (controls). METHODS: We obtained liver within 10 minutes after collection from 30 patients with chronic HBV infection (hepatitis B e antigen-positive or -negative, with or without hepatitis) and 42 controls (most with fatty liver disease). The liver tissues were analyzed by histology, immunohistochemistry, quantitative reverse-transcription polymerase chain reaction, in situ hybridization, HBV RNA quantification, and HBV genotyping; some specimens were incubated with toll-like receptor (TLR) ligands (polyinosinic-polycytidylic acid) or infected with Sendai virus and then analyzed. RESULTS: Liver specimens from patients with HBV infection were not expressing more IFN or ISGs than those from control patients, indicating that chronic HBV infection did not activate an innate immune response. However, liver specimens from patients with HBV infection did produce IFN and induce expression of ISGs following activation of TLR3 with poly(I:C) or Sendai virus infections, so the innate immune response is not suppressed in these tissues. CONCLUSION: Liver tissues from patients with chronic HBV infection do not have induction of an innate immune response, but this response can be activated by other factors (TLR3 binding, Sendai virus infection) in HBV-infected liver tissue. These findings support the hypothesis that HBV is invisible to pattern recognition receptors.


Assuntos
Vírus da Hepatite B/imunologia , Hepatite B/imunologia , Hepatócitos/imunologia , Imunidade Inata/imunologia , Fígado/imunologia , Adulto , Biópsia , Estudos de Casos e Controles , Feminino , Hepatite B/patologia , Hepatite B/virologia , Hepatócitos/virologia , Humanos , Fatores Reguladores de Interferon/metabolismo , Interferons/biossíntese , Fígado/patologia , Fígado/virologia , Masculino
4.
Proc Natl Acad Sci U S A ; 113(5): 1381-6, 2016 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-26787912

RESUMO

Compensatory signaling pathways in tumors confer resistance to targeted therapy, but the pathways and their mechanisms of activation remain largely unknown. We describe a procedure for quantitative proteomics and phosphoproteomics on snap-frozen biopsies of hepatocellular carcinoma (HCC) and matched nontumor liver tissue. We applied this procedure to monitor signaling pathways in serial biopsies taken from an HCC patient before and during treatment with the multikinase inhibitor sorafenib. At diagnosis, the patient had an advanced HCC. At the time of the second biopsy, abdominal imaging revealed progressive disease despite sorafenib treatment. Sorafenib was confirmed to inhibit MAPK signaling in the tumor, as measured by reduced ribosomal protein S6 kinase phosphorylation. Hierarchical clustering and enrichment analysis revealed pathways broadly implicated in tumor progression and resistance, such as epithelial-to-mesenchymal transition and cell adhesion pathways. Thus, we describe a protocol for quantitative analysis of oncogenic pathways in HCC biopsies and obtained first insights into the effect of sorafenib in vivo. This protocol will allow elucidation of mechanisms of resistance and enable precision medicine.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Niacinamida/análogos & derivados , Compostos de Fenilureia/uso terapêutico , Fosfoproteínas/metabolismo , Proteômica , Biópsia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Niacinamida/uso terapêutico , Fosforilação , Sorafenibe
5.
Hepatology ; 62(3): 702-14, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25999047

RESUMO

UNLABELLED: Hepatitis C virus (HCV) is a positive-strand RNA virus that primarily infects human hepatocytes. Infections with HCV constitute a global health problem, with 180 million people currently chronically infected. Recent studies have reported that cholesterol 25-hydroxylase (CH25H) is expressed as an interferon-stimulated gene and mediates antiviral activities against different enveloped viruses through the production of 25-hydroxycholesterol (25HC). However, the intrinsic regulation of human CH25H (hCH25H) expression within the liver as well as its mechanistic effects on HCV infectivity remain elusive. In this study, we characterized the expression of hCH25H using liver biopsies and primary human hepatocytes. In addition, the antiviral properties of this protein and its enzymatic product, 25HC, were further characterized against HCV in tissue culture. Levels of hCH25H messenger RNA were significantly up-regulated both in HCV-positive liver biopsies and in HCV-infected primary human hepatocytes. The expression of hCH25H in primary human hepatocytes was primarily and transiently induced by type I interferon. Transient expression of hCH25H in human hepatoma cells restricted HCV infection in a genotype-independent manner. This inhibition required the enzymatic activity of CH25H. We observed an inhibition of viral membrane fusion during the entry process by 25HC, which was not due to a virucidal effect. Yet the primary effect by 25HC on HCV was at the level of RNA replication, which was observed using subgenomic replicons of two different genotypes. Further analysis using electron microscopy revealed that 25HC inhibited formation of the membranous web, the HCV replication factory, independent of RNA replication. CONCLUSION: Infection with HCV causes up-regulation of interferon-inducible CH25H in vivo, and its product, 25HC, restricts HCV primarily at the level of RNA replication by preventing formation of the viral replication factory.


Assuntos
Hepacivirus/genética , Interferons/farmacologia , Esteroide Hidroxilases/genética , Internalização do Vírus/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Biópsia por Agulha , Células Cultivadas , Replicação do DNA/efeitos dos fármacos , Regulação Viral da Expressão Gênica , Hepatite C Crônica/patologia , Hepatócitos/metabolismo , Humanos , Sensibilidade e Especificidade , Regulação para Cima/efeitos dos fármacos
6.
Hepatology ; 59(3): 911-23, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24114970

RESUMO

UNLABELLED: Hepatocellular carcinoma (HCC) is among the leading causes of cancer-related death. Despite the advances in diagnosis and management of HCC, the biology of this tumor remains poorly understood. Recent evidence highlighted long noncoding RNAs (lncRNAs) as crucial determinants of HCC development. In this study we report the lncRNA HOXA transcript at the distal tip (HOTTIP) as significantly up-regulated in HCC specimens. The HOTTIP gene is located in physical contiguity with HOXA13 and directly controls the HOXA locus gene expression by way of interaction with the WDR5/MLL complex. HOX genes encode transcription factors regulating embryonic development and cell fate. We previously described HOX genes deregulation to be involved in hepatocarcinogenesis. Indeed, we observed the marked up-regulation of HOXA13 in HCC. Here, by correlating clinicopathological and expression data, we demonstrate that the levels of HOTTIP and HOXA13 are associated with HCC patients' clinical progression and predict disease outcome. In contrast to the majority of similar studies, our data were obtained from snap-frozen needle HCC biopsies (n=52) matched with their nonneoplastic counterparts collected from patients who had not yet received any HCC-tailored therapeutic treatments at the time of biopsy. In addition, taking advantage of gain and loss of function experiments in liver cancer-derived cell lines (HuH-6 and HuH-7), we uncover a novel bidirectional regulatory loop between HOTTIP/HOXA13. CONCLUSION: Our study highlights the key role of HOTTIP and HOXA13 in HCC development by associating their expression with metastasis and survival in HCC patients, provides novel insights on the function of lncRNA-driven hepatocarcinogenesis, and paves the way for further investigation about the possible role of HOTTIP as a predictive biomarker of HCC.


Assuntos
Carcinoma Hepatocelular/genética , Proteínas de Homeodomínio/genética , Neoplasias Hepáticas/genética , RNA Longo não Codificante/genética , Idoso , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/secundário , Linhagem Celular Transformada , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Gradação de Tumores , Valor Preditivo dos Testes , RNA Interferente Pequeno/genética
7.
J Gen Virol ; 94(Pt 10): 2208-2214, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23907395

RESUMO

Infectious hepatitis C virus (HCV) particle assembly starts at the surface of lipid droplets, cytoplasmic organelles responsible for neutral fat storage. We analysed the relationship between HCV and seipin, a protein involved in lipid droplet maturation. Although seipin overexpression did not affect the total mean volume occupied by lipid droplets nor the total triglyceride and cholesterol ester levels per cell, it caused an increase in the mean diameter of lipid droplets by 60 %, while decreasing their total number per cell. The latter two effects combined resulted in a 34 % reduction of the total outer surface area of lipid droplets per cell, with a proportional decrease in infectious viral particle production, probably due to a defect in particle assembly. These results suggest that the available outer surface of lipid droplets is a critical factor for HCV release, independent of the neutral lipid content of the cell.


Assuntos
Subunidades gama da Proteína de Ligação ao GTP/metabolismo , Hepacivirus/fisiologia , Lipídeos/química , Linhagem Celular Tumoral , Subunidades gama da Proteína de Ligação ao GTP/genética , Regulação da Expressão Gênica/fisiologia , Humanos , Internalização do Vírus , Replicação Viral/fisiologia
8.
Mol Oncol ; 16(3): 665-682, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34863035

RESUMO

Hepatocellular carcinomas (HCCs) usually arise from chronic liver disease (CLD). Precancerous cells in chronically inflamed environments may be 'epigenetically primed', sensitising them to oncogenic transformation. We investigated whether epigenetic priming in CLD may affect HCC outcomes by influencing the genomic and transcriptomic landscapes of HCC. Analysis of DNA methylation arrays from 10 paired CLD-HCC identified 339 shared dysregulated CpG sites and 18 shared differentially methylated regions compared with healthy livers. These regions were associated with dysregulated expression of genes with relevance in HCC, including ubiquitin D (UBD), cytochrome P450 family 2 subfamily C member 19 (CYP2C19) and O-6-methylguanine-DNA methyltransferase (MGMT). Methylation changes were recapitulated in an independent cohort of nine paired CLD-HCC. High CLD methylation score, defined using the 124 dysregulated CpGs in CLD and HCC in both cohorts, was associated with poor survival, increased somatic genetic alterations and TP53 mutations in two independent HCC cohorts. Oncogenic transcriptional and methylation dysregulation is evident in CLD and compounded in HCC. Epigenetic priming in CLD sculpts the transcriptional landscape of HCC and creates an environment favouring the acquisition of genetic alterations, suggesting that the extent of epigenetic priming in CLD could influence disease outcome.


Assuntos
Carcinoma Hepatocelular , Epigênese Genética , Hepatopatias , Neoplasias Hepáticas , Carcinoma Hepatocelular/patologia , Doença Crônica , Metilação de DNA/genética , Redes Reguladoras de Genes , Humanos , Hepatopatias/complicações , Hepatopatias/metabolismo , Neoplasias Hepáticas/patologia , Oncogenes
9.
Cell Mol Gastroenterol Hepatol ; 9(2): 195-218, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31445190

RESUMO

BACKGROUND & AIMS: The characterization of T cells infiltrating hepatocellular carcinoma (HCC) provides information on cancer immunity and also on selection of patients with precise indication of immunotherapy. The aim of the study was to characterize T-cell populations within tumor tissue and compare them with non-neoplastic liver tissue as well as circulating cells of the same patients. METHODS: The presence of unique cell populations was investigated in 36 HCC patients by multidimensional flow cytometry followed by t-distributed stochastic neighbor embedding analysis. Functional activity of tumor-infiltrating T cells was determined after activation by phorbol 12-myristate 13-acetate and ionomycin. RESULTS: Within the tumor there were more cells expressing CD137 and ICOS than in non-neoplastic liver tissue, possibly after recent antigenic activation. These cells contained several populations, including the following: (1) functionally impaired, proliferating CD4+ cells co-expressing Inducible T-cell costimulator (ICOS) and T cell immunoreceptor with Ig and ITIM domains (TIGIT); (2) functionally active CD8+ cells co-expressing CD38 and Programmed cell-death protein 1 (PD1); and (3) CD4-CD8 double-negative T-cell receptor αß and γδ cells (both non-major histocompatibility complex-restricted T cells). When the identified clusters were compared with histologic classification performed on the same samples, an accumulation of activated T cells was observed in immune-inflamed HCC. The same analyses performed in 7 patients receiving nivolumab treatment showed a remarkable reduction in the functionally impaired CD4+ cells, which returned to almost normal activity over time. CONCLUSIONS: Unique populations of activated T cells are present in HCC tissue, whose antigen specificity remains to be investigated. Some of these cell populations are functionally impaired and nivolumab treatment restores their responsiveness. The finding of ongoing immune response within the tumor shows which lymphocyte populations are impaired within the HCC and identifies the patients who might take benefit from immunotherapy.


Assuntos
Carcinoma Hepatocelular/imunologia , Neoplasias Hepáticas/imunologia , Fígado/imunologia , Linfócitos do Interstício Tumoral/imunologia , Linfócitos T/imunologia , Idoso , Idoso de 80 Anos ou mais , Biópsia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Estudos de Coortes , Feminino , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Proteína Coestimuladora de Linfócitos T Induzíveis/metabolismo , Fígado/citologia , Fígado/patologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Linfócitos do Interstício Tumoral/metabolismo , Masculino , Pessoa de Meia-Idade , Nivolumabe/farmacologia , Nivolumabe/uso terapêutico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/metabolismo , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo
10.
Hepatol Commun ; 3(7): 971-986, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31334445

RESUMO

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related deaths worldwide. Treatment options for patients with advanced-stage disease are limited. A major obstacle in drug development is the lack of an in vivo model that accurately reflects the broad spectrum of human HCC. Patient-derived xenograft (PDX) tumor mouse models could overcome the limitations of cancer cell lines. PDX tumors maintain the genetic and histologic heterogeneity of the originating tumors and are used for preclinical drug development in various cancers. Controversy exists about their genetic and molecular stability through serial passaging in mice. We aimed to establish PDX models from human HCC biopsies and to characterize their histologic and molecular stability during serial passaging. A total of 54 human HCC needle biopsies that were derived from patients with various underlying liver diseases and tumor stages were transplanted subcutaneously into immunodeficient, nonobese, diabetic/severe combined immunodeficiency gamma-c mice; 11 successfully engrafted. All successfully transplanted HCCs were Edmondson grade III or IV. HCC PDX tumors retained the histopathologic, transcriptomic, and genomic characteristics of the original HCC biopsies over 6 generations of retransplantation. These characteristics included Edmondson grade, expression of tumor markers, tumor gene signature, tumor-associated mutations, and copy number alterations. Conclusion: PDX mouse models can be established from undifferentiated HCCs, with an overall success rate of approximately 20%. The transplanted tumors represent the entire spectrum of the molecular landscape of HCCs and preserve the characteristics of the originating tumors through serial passaging. HCC PDX models are a promising tool for preclinical personalized drug development.

11.
Cell Rep ; 24(5): 1363-1376, 2018 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-30067989

RESUMO

Hepatocellular carcinoma (HCC) is the most common primary liver cancer and the second most frequent cause of cancer-related mortality worldwide. The multikinase inhibitor sorafenib is the only treatment option for advanced HCC. Due to tumor heterogeneity, its efficacy greatly varies between patients and is limited due to adverse effects and drug resistance. Current in vitro models fail to recapitulate key features of HCCs. We report the generation of long-term organoid cultures from tumor needle biopsies of HCC patients with various etiologies and tumor stages. HCC organoids retain the morphology as well as the expression pattern of HCC tumor markers and preserve the genetic heterogeneity of the originating tumors. In a proof-of-principle study, we show that liver cancer organoids can be used to test sensitivity to sorafenib. In conclusion, organoid models can be derived from needle biopsies of liver cancers and provide a tool for developing tailored therapies.


Assuntos
Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Organoides/patologia , Idoso , Idoso de 80 Anos ou mais , Animais , Células Cultivadas , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Técnicas de Cultura de Tecidos/métodos
12.
EMBO Mol Med ; 9(6): 816-834, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28360091

RESUMO

Hepatitis C virus (HCV) is widely used to investigate host-virus interactions. Cellular responses to HCV infection have been extensively studied in vitro However, in human liver, interferon (IFN)-stimulated gene expression can mask direct transcriptional responses to infection. To better characterize the direct effects of HCV infection in vivo, we analyze the transcriptomes of HCV-infected patients lacking an activated endogenous IFN system. We show that expression changes observed in these patients predominantly reflect immune cell infiltrates rather than cell-intrinsic pathways. We also investigate the transcriptomes of patients with endogenous IFN activation, which paradoxically cannot eradicate viral infection. We find that most IFN-stimulated genes are induced by both recombinant IFN therapy and the endogenous IFN system, but with lower induction levels in the latter, indicating that the innate immune response in chronic hepatitis C is too weak to clear the virus. We show that coding and non-coding transcripts have different expression dynamics following IFN treatment. Several microRNA primary transcripts, including that of miR-122, are significantly down-regulated in response to IFN treatment, suggesting a new mechanism for IFN-induced expression fine-tuning.


Assuntos
Antivirais/administração & dosagem , Perfilação da Expressão Gênica , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/patologia , Fatores Imunológicos/análise , Interferon-alfa/administração & dosagem , Fígado/patologia , Biópsia , Hepatite C Crônica/imunologia , Humanos , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/genética , MicroRNAs/análise , MicroRNAs/genética , Patologia Molecular
13.
J Pathol Clin Res ; 2(2): 80-92, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27499918

RESUMO

Molecular classification of hepatocellular carcinomas (HCC) could guide patient stratification for personalized therapies targeting subclass-specific cancer 'driver pathways'. Currently, there are several transcriptome-based molecular classifications of HCC with different subclass numbers, ranging from two to six. They were established using resected tumours that introduce a selection bias towards patients without liver cirrhosis and with early stage HCCs. We generated and analyzed gene expression data from paired HCC and non-cancerous liver tissue biopsies from 60 patients as well as five normal liver samples. Unbiased consensus clustering of HCC biopsy profiles identified 3 robust classes. Class membership correlated with survival, tumour size and with Edmondson and Barcelona Clinical Liver Cancer (BCLC) stage. When focusing only on the gene expression of the HCC biopsies, we could validate previously reported classifications of HCC based on expression patterns of signature genes. However, the subclass-specific gene expression patterns were no longer preserved when the fold-change relative to the normal tissue was used. The majority of genes believed to be subclass-specific turned out to be cancer-related genes differentially regulated in all HCC patients, with quantitative rather than qualitative differences between the molecular subclasses. With the exception of a subset of samples with a definitive ß-catenin gene signature, biological pathway analysis could not identify class-specific pathways reflecting the activation of distinct oncogenic programs. In conclusion, we have found that gene expression profiling of HCC biopsies has limited potential to direct therapies that target specific driver pathways, but can identify subgroups of patients with different prognosis.

14.
Swiss Med Wkly ; 145: w14200, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26588016

RESUMO

QUESTIONS: Regular surveillance of patients at risk for hepatocellular carcinoma (HCC) has been recommended by international guidelines and is practiced in many hepatology clinics. However, little is known about the effectiveness and the costs of 6 monthly ultrasound surveillance. METHODS: Clinical charts, ultrasound reports and reports of additional examinations (computed tomography, magnetic resonance imaging, liver biopsy) were systematically reviewed. The tumour stage of HCC detected in the surveillance programme was compared with stages of patients not surveyed. The number needed to survey to detect a HCC and the costs per detected HCC were calculated. RESULTS: In the 2-year period 2011-2012, 696 ultrasound examinations in 285 patients were performed in the hepatology outpatient clinic of the University Hospital Basel, Switzerland. Focal lesions were detected by ultrasound in 88 of the 285 patients. Nine of them had a newly diagnosed HCC. All of them were at early stage (Barcelona Clinic Liver Cancer staging 0 or A) and 8 of 9 fulfilled Milan Criteria. In this 2-year surveillance period, the number needed to screen was 32 patients. The calculated costs per detected HCC were 29 701 Swiss francs. CONCLUSIONS: In this retrospective analysis, HCC surveillance resulted in the detection of HCCs in an early stage. The number needed to screen and the costs of the surveillance are reasonably low.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Hepatite B Crônica/diagnóstico por imagem , Cirrose Hepática/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Povo Asiático , Biópsia , População Negra , Carcinoma Hepatocelular/etnologia , Detecção Precoce de Câncer , Feminino , Humanos , Neoplasias Hepáticas/etnologia , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Suíça/epidemiologia , Tomografia Computadorizada por Raios X , Ultrassonografia , alfa-Fetoproteínas/análise
15.
Swiss Med Wkly ; 144: w13911, 2014 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-24496744

RESUMO

BACKGROUND: Delayed recognition of sepsis and inappropriate initial antibiotic therapy are associated with increased mortality and morbidity. The early detection of the causative organism in sepsis is an unmet clinical need. A novel multiplex real-time polymerase chain reaction (MRT-PCR) (SeptiFast®) technique may provide the microbiological diagnosis within six hours. METHODS: We assessed the diagnostic accuracy of blood cultures and MRT-PCR in a comparative diagnostic cohort study in 110 consecutive adult patients presenting to the emergency department (ED) with suspected sepsis. RESULTS: We collected 205 corresponding PCR samples and blood culture (BC) pairs from the 110 patients. There was moderate to high concordance between PCR and BC with 181 (88%) matching and 24 (12%) mismatching samples. The diagnostic accuracy of MRT-PCR in detecting sepsis and its causative organism was comparable to that of BCs. The additional use of MRT-PCR significantly reduced the time to microbiological diagnosis as compared to the use of conventional microbiological methods alone (mean time gained 3.9 hours, range 0-66 hours, p <0.001). CONCLUSION: Diagnostic accuracy of BCs and MRT-PCR in the early diagnosis of sepsis and its causative organism in the ED are comparable. However, MRT-PCR reduces the time to microbiological diagnosis. Whether a more rapid detection of the organism by MRT-PCR could improve the outcome of patients has to be assessed in large prospective randomised trials.


Assuntos
Bacteriemia/diagnóstico , DNA Bacteriano/análise , DNA Fúngico/análise , Serviço Hospitalar de Emergência , Fungemia/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real , Idoso , Bacteriemia/sangue , Bacteriemia/microbiologia , Sangue/microbiologia , Análise Química do Sangue , Diagnóstico Precoce , Feminino , Fungemia/sangue , Fungemia/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Método Simples-Cego , Fatores de Tempo
16.
J Exp Med ; 211(5): 857-68, 2014 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-24752298

RESUMO

The molecular mechanisms that link IFN-λ3 genotypes to differential induction of interferon (IFN)-stimulated genes (ISGs) in the liver of patients with chronic hepatitis C (CHC) are not known. We measured the expression of IFN-λ and of the specific IFN-λ receptor chain (IFN-λR1) in 122 liver biopsies of patients with CHC and 53 control samples. The IFN-λ3 genotype was not associated with differential expression of IFN-λ, but rather IFN-λR1. In a series of 30 primary human hepatocyte (PHH) samples, IFN-λR1 expression was low but could be induced with IFN-α. IFN-α-induced IFN-λR1 expression was significantly stronger in PHHs carrying the minor IFN-λ3 allele. The analysis of liver biopsies of patients with CHC revealed a strong association of high IFN-λR1 expression with elevated ISG expression, with IFN-λ3 minor alleles, and with nonresponse to pegylated IFN-α and ribavirin. The findings provide a missing link between the IFN-λ3 genotype and the associated phenotype of treatment nonresponse.


Assuntos
Hepatite C Crônica/metabolismo , Interferons/metabolismo , Fígado/metabolismo , Receptores de Interferon/metabolismo , Biópsia , Western Blotting , Estudos de Casos e Controles , Primers do DNA/genética , Imunofluorescência , Genótipo , Humanos , Hibridização in Situ Fluorescente , Interferon-alfa/uso terapêutico , Microscopia Confocal , Polimorfismo de Nucleotídeo Único/genética , Reação em Cadeia da Polimerase em Tempo Real , Suíça
17.
Int J Cardiol ; 142(3): 265-72, 2010 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-19185372

RESUMO

OBJECTIVES: This study aimed to examine the influence of history of heart failure (HF) on circulating levels, diagnostic accuracy and prognostic value of B-type natriuretic peptide (BNP) in patients presenting with all cause dyspnea at the emergency department. BACKGROUND: BNP has been shown to be very helpful in diagnosis and prognosis of HF. Due to chronically elevated cardiac filling pressures, patients with a history of HF might have higher BNP levels and therefore diagnostic and prognostic properties of BNP may be affected. METHODS: We analyzed circulating levels, diagnostic accuracy and prognostic value of BNP in 388 patients without a previous history of HF and compared these to data to 64 patients with a history of HF included in the B-type Natriuretic Peptide for Acute Shortness of Breath Evaluation (BASEL) Study. RESULTS: Baseline BNP levels were higher in patients with a history of HF (median 814 pg/ml [353-1300 pg/ml] vs. 216 pg/ml [45-801 pg/ml], p<0.001). Diagnostic accuracy of BNP to identify HF was comparable in patients with (AUC=0.804; 95% CI 0.628-0.980) and in patients without history of HF (AUC=0.883; 95% CI 0.848-0.919, p=0.389). Prognostic ability of BNP to predict one-year mortality was lower in overall patients with history of HF (AUC=0.458; 95%CI 0.294-0.622) compared to patients without history of HF (AUC=0.710; 95% CI 0.653-0.768, p<0.05). CONCLUSIONS: In patients with history of HF, BNP levels retain diagnostic accuracy. Ability to predict one-year mortality was decreased in unselected patients, but not in patients with acute HF-induced dyspnea.


Assuntos
Dispneia/sangue , Dispneia/mortalidade , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/mortalidade , Peptídeo Natriurético Encefálico/sangue , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Dispneia/diagnóstico , Feminino , Testes Genéticos , Insuficiência Cardíaca/diagnóstico , Humanos , Estimativa de Kaplan-Meier , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Prognóstico , Curva ROC , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
J Am Coll Cardiol ; 54(1): 60-8, 2009 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-19555842

RESUMO

OBJECTIVES: The purpose of this study was to examine the incremental value of copeptin for rapid rule out of acute myocardial infarction (AMI). BACKGROUND: The rapid and reliable exclusion of AMI is a major unmet clinical need. Copeptin, the C-terminal part of the vasopressin prohormone, as a marker of acute endogenous stress may be useful in this setting. METHODS: In 487 consecutive patients presenting to the emergency department with symptoms suggestive of AMI, we measured levels of copeptin at presentation, using a novel sandwich immunoluminometric assay in a blinded fashion. The final diagnosis was adjudicated by 2 independent cardiologists using all available data. RESULTS: The adjudicated final diagnosis was AMI in 81 patients (17%). Copeptin levels were significantly higher in AMI patients compared with those in patients having other diagnoses (median 20.8 pmol/l vs. 6.0 pmol/l, p < 0.001). The combination of troponin T and copeptin at initial presentation resulted in an area under the receiver-operating characteristic curve of 0.97 (95% confidence interval: 0.95 to 0.98), which was significantly higher than the 0.86 (95% confidence interval: 0.80 to 0.92) for troponin T alone (p < 0.001). A copeptin level <14 pmol/l in combination with a troponin T < or =0.01 microg/l correctly ruled out AMI with a sensitivity of 98.8% and a negative predictive value of 99.7%. CONCLUSIONS: The additional use of copeptin seems to allow a rapid and reliable rule out of AMI already at presentation and may thereby obviate the need for prolonged monitoring and serial blood sampling in the majority of patients. (Advantageous Predictors of Acute Coronary Syndromes Evaluation [APACE]; NCT00470587).


Assuntos
Glicopeptídeos/sangue , Infarto do Miocárdio/diagnóstico , Troponina T/sangue , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Estudos Prospectivos
19.
Heart ; 93(9): 1093-7, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17395674

RESUMO

OBJECTIVES: To quantify the prognostic utility of QRS and QTc interval prolongation in patients presenting with acute destabilised heart failure (ADHF) to the emergency department (ED). DESIGN: Prospective cohort study among patients enrolled in the B-Type Natriuretic Peptide for Acute Shortness of Breath Evaluation (BASEL) study. QRS and QT intervals were measured in 173 consecutive patients with ADHF. QT interval was corrected using the Bazett formula. The primary end point was all-cause mortality during the 720-day follow-up. RESULTS: QRS interval was prolonged (> or =120 ms) in 27% of patients, and QTc interval was prolonged (> or =440 ms) in 72% of patients. Baseline demographic and clinical characteristics were comparable in patients with normal and prolonged QRS or QTc intervals. A total of 78 patients died during follow-up. Interestingly, the 720-day mortality was similar in patients with prolonged and normal QTc (44% vs 42%, p = 0.546), but was significantly higher in patients with prolonged QRS interval than in those with normal QRS (59% vs 37%, p = 0.004). In Cox proportional hazards analysis, prolonged QRS interval was associated with a nearly twofold increase in mortality (HR 1.94, 95% CI 1.22 to 3.07; p = 0.005). This association persisted after adjustment for variables routinely available in the ED. CONCLUSIONS: Prolonged QRS interval, but not prolonged QTc interval, is associated with increased long-term mortality in patients with ADHF.


Assuntos
Arritmias Cardíacas/etiologia , Insuficiência Cardíaca/complicações , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Eletrocardiografia , Serviço Hospitalar de Emergência , Métodos Epidemiológicos , Feminino , Insuficiência Cardíaca/fisiopatologia , Humanos , Síndrome do QT Longo/etiologia , Masculino , Pessoa de Meia-Idade , Prognóstico
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