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1.
Hepatology ; 77(4): 1348-1365, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35971873

RESUMO

BACKGROUND AND AIMS: Hepatitis B virus (HBV) infection causes oxidative stress (OS) and alters mitochondria in experimental models. Our goal was to investigate whether HBV might alter liver mitochondria also in humans, and the resulting mitochondrial stress might account for the progression of fibrosis in chronic hepatitis B (CHB). APPROACH AND RESULTS: The study included 146 treatment-naïve CHB mono-infected patients. Patients with CHB and advanced fibrosis (AF) or cirrhosis (F3-F4) were compared to patients with no/mild-moderate fibrosis (F0-F2). Patients with CHB were further compared to patients with chronic hepatitis C (CHC; n = 33), nonalcoholic steatohepatatis (NASH; n = 12), and healthy controls ( n = 24). We detected oxidative damage to mitochondrial DNA (mtDNA), including mtDNA strand beaks, and identified multiple mtDNA deletions in patients with F3-F4 as compared to patients with F0-F2. Alterations in mitochondrial function, mitochondrial unfolded protein response, biogenesis, mitophagy, and liver inflammation were observed in patients with AF or cirrhosis associated with CHB, CHC, and NASH. In vitro , significant increases of the mitochondrial formation of superoxide and peroxynitrite as well as mtDNA damage, nitration of the mitochondrial respiratory chain complexes, and impairment of complex I occurred in HepG2 cells replicating HBV or transiently expressing hepatitits B virus X protein. mtDNA damage and complex I impairment were prevented with the superoxide-scavenging Mito-Tempo or with inducible nitric oxide synthase (iNOS)-specific inhibitor 1400 W. CONCLUSIONS: Our results emphasized the importance of mitochondrial OS, mtDNA damage, and associated alterations in mitochondrial function and dynamics in AF or cirrhosis in CHB and NASH. Mitochondria might be a target in drug development to stop fibrosis progression.


Assuntos
Hepatite B Crônica , Hepatite B , Hepatite C Crônica , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatite C Crônica/complicações , Hepatite C Crônica/genética , Superóxidos , Cirrose Hepática/complicações , Fibrose , Vírus da Hepatite B/genética , Hepatite B/complicações , DNA Mitocondrial , Mitocôndrias
2.
Gut ; 70(12): 2373-2382, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34535538

RESUMO

Regulation of alternative splicing is one of the most efficient mechanisms to enlarge the proteomic diversity in eukaryotic organisms. Many viruses hijack the splicing machinery following infection to accomplish their replication cycle. Regarding the HBV, numerous reports have described alternative splicing events of the long viral transcript (pregenomic RNA), which also acts as a template for viral genome replication. Alternative splicing of HBV pregenomic RNAs allows the synthesis of at least 20 spliced variants. In addition, almost all these spliced forms give rise to defective particles, detected in the blood of infected patients. HBV-spliced RNAs have long been unconsidered, probably due to their uneasy detection in comparison to unspliced forms as well as for their dispensable role during viral replication. However, recent data highlighted the relevance of these HBV-spliced variants through (1) the trans-regulation of the alternative splicing of viral transcripts along the course of liver disease; (2) the ability to generate defective particle formation, putative biomarker of the liver disease progression; (3) modulation of viral replication; and (4) their intrinsic propensity to encode for novel viral proteins involved in liver pathogenesis and immune response. Altogether, tricky regulation of HBV alternative splicing may contribute to modulate multiple viral and cellular processes all along the course of HBV-related liver disease.


Assuntos
Processamento Alternativo , Vírus da Hepatite B/genética , Splicing de RNA , Genoma Viral , Humanos , Proteômica
3.
Int J Gynecol Cancer ; 31(6): 920-924, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33262113

RESUMO

BACKGROUND: Patients undergoing neoadjuvant chemotherapy before surgery for advanced ovarian cancer may have impaired functional capacity, nutritional status, and emotional well-being. PRIMARY OBJECTIVES: TRAINING-01 aims to determine if a connected pre-habilitation program during neoadjuvant chemotherapy for patients treated for an advanced ovarian cancer will improve physical capacity before major abdomino-pelvic surgery. STUDY HYPOTHESIS: A pre-habilitation program during neoadjuvant chemotherapy will bring a fitter patient to surgery and will decrease treatment morbidity and improve oncological outcomes. TRIAL DESIGN: This study is a prospective, multi-center, phase III study. The pre-habilitation program consists of providing multi-dimensional support during neoadjuvant chemotherapy using connected devices. The control group will receive usual care. MAJOR INCLUSION/EXCLUSION CRITERIA: Eligible patients will be women with International Federation of Gynecology and Obstetrics stage III-IV advanced ovarian cancer undergoing neoadjuvant chemotherapy. Patients must be able to perform a cardiopulmonary exercise test. PRIMARY ENDPOINTS: The primary endpoint will be the comparison of the variation in maximum oxygen uptake (VO2 max) between baseline and surgery in the pre-habilitation group and control groups. SAMPLE SIZE: 136 patients (68 per arm) will be recruited to demonstrate a medium standardized effect d=0.5 in the variations of VO2 max between baseline and surgery. ESTIMATED DATES FOR COMPLETING ACCRUAL AND PRESENTING RESULTS: The duration of the study includes 24 months of recruitment and 5 years of follow up. We anticipate reporting primary endpoint results in 2024. TRIAL REGISTRATION: TRAINING-01-IPC 2018-039 (NCT04451369).


Assuntos
Terapia Neoadjuvante/métodos , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/terapia , Exercício Pré-Operatório/psicologia , Feminino , Humanos , Estudos Prospectivos
4.
Carcinogenesis ; 41(3): 358-367, 2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31175830

RESUMO

The hepatitis B virus X protein (HBx) has pleiotropic biological effects, which underlies its potential role in cell transformation. However, its involvement in hepatic fibrosis remains unclear. In this study, we wanted to clarify, in vivo, the role of HBx protein in the development of liver fibrosis. Mice transgenic for the full-length HBx (FL-HBx) were used. To create liver fibrosis, FL-HBx transgenic and control mice were chronically exposed to carbon tetrachloride (CCl4). Modulation of the expression of proteins involved in matrix remodeling, hepatic metabolism and epithelial-mesenchymal transition (EMT) were investigated. In transgenic mice, FL-HBx expression potentiates CCl4-induced liver fibrosis with increased expression of proteins involved in matrix remodeling (Collagen1a, α-Sma, PdgfR-ß, MMP-13). In FL-HBx transgenic mice, an increase in EMT was observed with a higher transcription of two inflammatory cytokines (TNF-α and TGF-ß) and a decrease of glutamine synthetase expression level. This was associated with a sustained cell cycle and hepatocyte polyploidy alteration consistent with p38 and ERK1/2 overactivation, increase of PLK1 transcription, accumulation of SQSTM1/p62 protein and increase expression of Beclin-1. This correlates with a higher expression of tumor progenitor cell markers (AFP, Ly6D and EpCam), indicating a higher risk of progression from fibrosis to hepatocellular carcinoma (HCC) in the presence of FL-HBx protein. In conclusion, our results show that FL-HBx protein enhances the development of liver fibrosis and contributes to the progression of liver disease from chronic hepatitis to HCC.


Assuntos
Carcinoma Hepatocelular/genética , Cirrose Hepática/genética , Neoplasias Hepáticas/genética , Transativadores/genética , Animais , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/virologia , Proliferação de Células/genética , Transformação Celular Neoplásica/genética , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Regulação Viral da Expressão Gênica/genética , Vírus da Hepatite B/genética , Vírus da Hepatite B/patogenicidade , Humanos , Cirrose Hepática/patologia , Cirrose Hepática/virologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Sistema de Sinalização das MAP Quinases , Camundongos , Camundongos Transgênicos , Células-Tronco Neoplásicas/patologia , Células-Tronco Neoplásicas/virologia , Proteína Sequestossoma-1/genética , Proteínas Virais Reguladoras e Acessórias
5.
Haematologica ; 105(1): 47-58, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31537691

RESUMO

Donor lymphocyte infusion has been used in the management of relapsed hematologic malignancies after allogeneic hematopoietic cell transplantation. It can eradicate minimal residual disease or be used to rescue a hematologic relapse, being able to induce durable remissions in a subset of patients. With the increased use of haploidentical hematopoietic cell transplantation, there is renewed interest in the use of donor lymphocytes to either treat or prevent disease relapse post transplant. Published retrospective and small prospective studies have shown encouraging results with therapeutic donor lymphocyte infusion in different haploidentical transplantation platforms. In this consensus paper, finalized on behalf of the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation, we summarize the available evidence on the use of donor lymphocyte infusion from haploidentical donor, and provide recommendations on its therapeutic, pre-emptive and prophylactic use in clinical practice.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Consenso , Humanos , Linfócitos , Estudos Prospectivos , Estudos Retrospectivos
7.
Gastroenterology ; 153(6): 1647-1661.e9, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28851562

RESUMO

BACKGROUND & AIMS: Hepatitis B virus (HBV) infects hepatocytes, but the mechanisms of the immune response against the virus and how it affects disease progression are unclear. METHODS: We performed studies with BALB/c Rag2-/-Il2rg-/-SirpaNODAlb-uPAtg/tg mice, stably engrafted with human hepatocytes (HUHEP) with or without a human immune system (HIS). HUHEP and HIS-HUHEP mice were given an intraperitoneal injection of HBV. Mononuclear cells were isolated from spleen and liver for analysis by flow cytometry. Liver was analyzed by immunohistochemistry and mRNA levels were measured by quantitative reverse transcription polymerase chain reaction (PCR). Plasma levels of HBV DNA were quantified by PCR reaction, and antigen-specific antibodies were detected by immunocytochemistry of HBV-transfected BHK-21 cells. RESULTS: Following HBV infection, a complete viral life cycle, with production of HBV DNA, hepatitis B e (HBe), core (HBc) and surface (HBs) antigens, and covalently closed circular DNA, was observed in HUHEP and HIS-HUHEP mice. HBV replicated unrestricted in HUHEP mice resulting in high viral titers without pathologic effects. In contrast, HBV-infected HIS-HUHEP mice developed chronic hepatitis with 10-fold lower titers and antigen-specific IgGs, (anti-HBs, anti-HBc), consistent with partial immune control. HBV-infected HIS-HUHEP livers contained infiltrating Kupffer cells, mature activated natural killer cells (CD69+), and PD-1+ effector memory T cells (CD45RO+). Reducing the viral inoculum resulted in more efficient immune control. Plasma from HBV-infected HIS-HUHEP mice had increased levels of inflammatory and immune-suppressive cytokines (C-X-C motif chemokine ligand 10 and interleukin 10), which correlated with populations of intrahepatic CD4+ T cells (CD45RO+PD-1+). Mice with high levels of viremia had HBV-infected liver progenitor cells. Giving the mice the nucleoside analogue entecavir reduced viral loads and decreased liver inflammation. CONCLUSION: In HIS-HUHEP mice, HBV infection completes a full life cycle and recapitulates some of the immunopathology observed in patients with chronic infection. Inoculation with different viral loads led to different immune responses and levels of virus control. We found HBV to infect liver progenitor cells, which could be involved in hepatocellular carcinogenesis. This is an important new system to study anti-HBV immune responses and screen for combination therapies against hepatotropic viruses.


Assuntos
Vírus da Hepatite B/crescimento & desenvolvimento , Hepatite B Crônica/virologia , Hepatócitos/virologia , Fígado/virologia , Baço/virologia , Carga Viral , Replicação Viral , Animais , DNA Viral/sangue , DNA Viral/genética , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/genética , Feminino , Regulação da Expressão Gênica , Predisposição Genética para Doença , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Hepatite B Crônica/genética , Hepatite B Crônica/imunologia , Hepatite B Crônica/metabolismo , Hepatócitos/imunologia , Hepatócitos/metabolismo , Interações Hospedeiro-Patógeno , Humanos , Imunidade Celular , Subunidade gama Comum de Receptores de Interleucina/deficiência , Subunidade gama Comum de Receptores de Interleucina/genética , Fígado/imunologia , Fígado/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Camundongos Knockout , Camundongos Transgênicos , Fenótipo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores Imunológicos/deficiência , Receptores Imunológicos/genética , Albumina Sérica Humana/genética , Albumina Sérica Humana/metabolismo , Baço/imunologia , Baço/metabolismo , Fatores de Tempo , Ativador de Plasminogênio Tipo Uroquinase/genética , Ativador de Plasminogênio Tipo Uroquinase/metabolismo
8.
Br J Cancer ; 116(3): 362-369, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28072763

RESUMO

BACKGROUND: Human Papillomavirus (HPV) infection is recognised as aetiological factor of carcinogenesis in oropharyngeal squamous cell carcinomas (OPC). HPV-related OPC respond better to treatments and have a significantly favourable outcome. Epithelial to mesenchymal transition (EMT) implicated in tumour invasion, is a hallmark of a poor prognosis in carcinomas. METHODS: We have studied the relationship of EMT markers (E-cadherin, ß-catenin and vimentin) with HPV infection (DNA and E6/E7 mRNA detection), p16INK4a expression and survival outcomes in a cohort of 296 patients with OPC. RESULTS: Among the 296 OPSSC, 26% were HPV positive, 20.3% had overt EMT (>25% of vimentin positive tumour cells). Lower E-cadherin expression was associated with a higher risk of distant metastasis in univariate (P=0.0110) and multivariate analyses (hazard ratios (HR)=6.86 (1.98; 23.84)). Vimentin expression tends towards worse metastasis-free survival (MFS; HR=2.53 (1.00; 6.41)) and was an independent prognostic factor of progression-free survival (HR=1.55 (1.03; 2.34)). CONCLUSIONS: There was a non significant association of EMT with HPV status. This may be explained by a mixed subpopulation of patients HPV positive with associated risk factors (HPV, tobacco and alcohol). Thus, the detection of EMT in OPC represents another reliable approach in the prognosis and the management of OPC whatever their HPV status.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma de Células Escamosas/diagnóstico , Transição Epitelial-Mesenquimal/fisiologia , Neoplasias Orofaríngeas/diagnóstico , Infecções por Papillomavirus/diagnóstico , Adulto , Idoso , Carcinoma de Células Escamosas/complicações , Carcinoma de Células Escamosas/terapia , Carcinoma de Células Escamosas/virologia , DNA Viral/análise , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Orofaríngeas/complicações , Neoplasias Orofaríngeas/terapia , Neoplasias Orofaríngeas/virologia , Papillomaviridae/genética , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/genética , Prognóstico
9.
J Hepatol ; 67(4): 687-699, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28600137

RESUMO

BACKGROUND & AIMS: Hepatitis B virus (HBV) RNA can undergo alternative splicing, but the relevance of this post-transcriptional regulation remains elusive. The mechanism of HBV alternative splicing regulation and its impact on liver pathogenesis were investigated. METHODS: HBV RNA-interacting proteins were identified by RNA pull-down, combined with mass spectrometry analysis. HBV splicing regulation was investigated in chemically and surgically induced liver damage, in whole HBV genome transgenic mice and in hepatoma cells. Viral and endogenous gene expression were quantified by quantitative reverse transcription polymerase chain reaction, Western blot and enzyme-linked immunosorbent assay. Resident liver immune cells were studied by fluorescence-activated cell sorting. RESULTS: HBV pregenomic RNA-interacting proteins were identified and 15% were directly related to the splicing machinery. Expression of these splicing factors was modulated in HBV transgenic mice with liver injuries and contributed to an increase of the HBV spliced RNA encoding for HBV splicing-generated protein (HBSP). HBSP transgenic mice with chemically induced liver fibrosis exhibited attenuated hepatic damage. The protective effect of HBSP resulted from a decrease of inflammatory monocyte/macrophage recruitment through downregulation of C-C motif chemokine ligand 2 (CCL2) expression in hepatocytes. In human hepatoma cells, the ability of HBSP to control CCL2 expression was confirmed and maintained in a whole HBV context. Finally, viral spliced RNA detection related to a decrease of CCL2 expression in the livers of HBV chronic carriers underscored this mechanism. CONCLUSION: The microenvironment, modified by liver injury, increased HBSP RNA expression through splicing factor regulation, which in turn controlled hepatocyte chemokine synthesis. This feedback mechanism provides a novel insight into liver immunopathogenesis during HBV infection. Lay summary: Hepatitis B virus persists for decades in the liver of chronically infected patients. Immune escape is one of the main mechanisms developed by this virus to survive. Our study highlights how the crosstalk between virus and liver infected cells may contribute to this immune escape.


Assuntos
Processamento Alternativo , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Processamento Alternativo/imunologia , Animais , Quimiocina CCL2/metabolismo , Vírus da Hepatite B/patogenicidade , Hepatite B Crônica/imunologia , Hepatite B Crônica/virologia , Humanos , Evasão da Resposta Imune/genética , Fígado/imunologia , Fígado/lesões , Fígado/virologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fatores de Processamento de RNA/metabolismo , RNA Viral/genética , RNA Viral/metabolismo
10.
Transpl Infect Dis ; 19(1)2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27775205

RESUMO

Hepatitis E virus (HEV) can cause chronic infection among immunocompromised patients, especially solid organ transplant recipients, and can evolve to cirrhosis. Several modes of transmission are known. Here we describe the first two cases, to our knowledge, of HEV infection transmitted by a kidney graft from the same infected donor that led to chronic hepatitis. Consequently, systematic screening of donors by HEV serology and HEV RNA detection by polymerase chain reaction, particularly in endemic regions, should be considered.


Assuntos
Aloenxertos/virologia , Vírus da Hepatite E/isolamento & purificação , Hepatite E/transmissão , Terapia de Imunossupressão/efeitos adversos , Transplante de Rim/efeitos adversos , RNA Viral/isolamento & purificação , Idoso , Hepatite E/sangue , Hepatite E/diagnóstico , Hepatite E/virologia , Hepatite Crônica/sangue , Hepatite Crônica/diagnóstico , Hepatite Crônica/virologia , Humanos , Hospedeiro Imunocomprometido , Masculino , Nefroesclerose/cirurgia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
11.
FASEB J ; 29(5): 1879-89, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25630972

RESUMO

Hepatitis B splicing-regulated protein (HBSP) of the hepatitis B virus (HBV) was uncovered a few years ago but its function remains unknown. HBSP expression occurs from a spliced viral transcript that increases during the course of liver disease. This study aimed at characterizing the impact of HBSP on cellular signaling pathways in vitro and on liver pathogenesis in transgenic (Tg) mice. By RT-qPCR array, NF-κB-inducible genes appeared modulated in HepG2 cells transduced with a HBSP-encoding lentivirus. Using luciferase and Western blot assays, we observed a decreased activation of the NF-κB pathway in HBSP-expressing cells following TNF-α treatment, as illustrated by lower levels of phosphorylated IκB-α. Meanwhile, the level of phosphorylated JNK increased together with the sensitivity to apoptosis. The contrasting effects on JNK and IκB-α activation upon TNF-α stimulation matched with a modulated maturation of TGF-ß-activated kinase 1 (TAK1) kinase, assessed by 2-dimensional SDS-PAGE. Inhibition of the NF-κB pathway by HBSP was confirmed in the liver of HBSP Tg mice and associated with a significant decrease of chemically induced chronic liver inflammation, as assessed by immunohistochemistry. In conclusion, HBSP contributes to limit hepatic inflammation during chronic liver disease and may favor HBV persistence by evading immune response.


Assuntos
Processamento Alternativo , Carcinoma Hepatocelular/metabolismo , Hepatite B/metabolismo , Inflamação/prevenção & controle , Neoplasias Hepáticas/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Proteínas Virais/genética , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Western Blotting , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/patologia , Proliferação de Células , Perfilação da Expressão Gênica , Hepatite B/imunologia , Hepatite B/virologia , Vírus da Hepatite B/fisiologia , Humanos , Inflamação/induzido quimicamente , Inflamação/imunologia , Inflamação/metabolismo , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , NF-kappa B/genética , NF-kappa B/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas , Proteínas Virais/metabolismo
12.
J Gen Virol ; 96(Pt 3): 614-625, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25519169

RESUMO

Hepatitis B virus X protein (HBx) is involved in the development of hepatocellular carcinoma (HCC). The HBx sequence is a preferential site of integration into the human genome, leading to the formation of C-terminal-truncated HBx proteins (Ct-HBx). We previously reported that Ct-HBx proteins were able to potentiate cell transformation in vitro. Our present goal was to compare the ability of Ct-HBx and full-length HBx (FL-HBx) proteins to develop or enhance HCC in transgenic mice. In the absence of treatment, neither Ct-HBx- nor FL-HBx-transgenic mice developed HCC. In young mice treated with diethylnitrosamine (DEN) at 8 months of age, a significantly higher incidence and number of liver lesions were observed in Ct-HBx mice than in FL-HBx and control mice. The earlier development of tumours in Ct-HBx-transgenic mice was associated with increased liver inflammation. At 10 months, macroscopic and microscopic analyses showed that, statistically, FL-HBx mice developed more liver lesions with a larger surface area than control mice. Furthermore, during DEN-induced initiation of HCC, Ct-HBx- and FL-HBx-transgenic mice showed higher expression of IL-6, TNF-α and IL-1ß transcripts, activation of STAT3, ERK and JNK proteins and an increase in cell apoptosis. In conclusion, in DEN-treated transgenic mice, the expression of Ct-HBx protein causes a more rapid onset of HCC than does FL-HBx protein. HBV genome integration leading to the expression of a truncated form of HBx protein may therefore facilitate HCC development in chronically infected patients.


Assuntos
Carcinoma Hepatocelular/virologia , Vírus da Hepatite B/patogenicidade , Neoplasias Hepáticas/virologia , Transativadores/metabolismo , Sequência de Aminoácidos , Animais , Apoptose , Carcinoma Hepatocelular/induzido quimicamente , Proliferação de Células , Dietilnitrosamina/toxicidade , Regulação Viral da Expressão Gênica , Hepatócitos/citologia , Hepatócitos/fisiologia , Hepatócitos/virologia , Neoplasias Hepáticas/induzido quimicamente , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Proteínas Virais Reguladoras e Acessórias
13.
J Proteome Res ; 13(2): 1002-11, 2014 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-24405156

RESUMO

The prevalence of head and neck squamous cell carcinoma (HNSCC) related to human papillomavirus (HPV) is increasing, unlike tobacco- and alcohol-associated cancers. To gain a clearer understanding of the molecular mechanisms implicated in HNSCC, depending on the presence or not of a viral sequence, we investigated the expression of proteins detected in the tumor regions of HNSCC patients. Twenty-two untreated HNSCC patients were selected according to the presence of HPV-16. For six patients, tumor and controlateral healthy tissues were tested for viral detection before quantitative proteomic analysis. After confirmation by Western blot, proteins were connected into a network, leading to investigate interleukin-6 (IL-6) by immunocytochemistry and ELISA. 41 ± 5% of proteins quantified by proteomics were differentially expressed in tumor compared with healthy regions. Among them, 36 proteins were retained as modulated in HPV-16 positive or negative tumors, including cytokeratins, tubulins, annexin A1, and serpin B1. Network analysis suggested a central role of IL-6, confirmed by overexpression of IL-6 in tumor tissues as in sera of HPV-negative HNSCC compared with HPV-16-positive tumors. This modulation may contribute to the survival and proliferation of cancer cells, although it was not related to tumor stage or to the level of HPV-16 DNA.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , Interleucina-6/metabolismo , Infecções por Papillomavirus/metabolismo , Idoso , Sequência de Bases , Western Blotting , Carcinoma de Células Escamosas/complicações , Carcinoma de Células Escamosas/virologia , Estudos de Casos e Controles , Estudos de Coortes , Primers do DNA , Ensaio de Imunoadsorção Enzimática , Feminino , Neoplasias de Cabeça e Pescoço/complicações , Neoplasias de Cabeça e Pescoço/virologia , Papillomavirus Humano 16/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/virologia , Reação em Cadeia da Polimerase em Tempo Real , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Carga Viral
14.
J Autoimmun ; 52: 29-35, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24440286

RESUMO

Myasthenia gravis (MG) is an autoimmune disease mainly mediated by anti-acetylcholine receptor (AChR) antibodies. In the late onset, a thymoma, tumor of the thymus, is quite frequent. However, the events leading to thymoma and MG are not understood. As thymoma-associated MG (MG-T) patients also display anti-interferon type I (IFN-I) neutralizing antibodies, we investigated if MG-T could be associated with an anti-viral signature. RT-PCR analyses demonstrated huge increases of IFN-I subtypes, IFN-α2, -α8, -ω and -ß, in thymoma-associated MG but not in thymomas without MG or in control thymuses. Next, we investigated if dsRNA signaling pathway involvement could be observed in MG-T, as recently observed in early-onset MG. We observed an abnormal regulation of dsRNA-sensing molecules with an increase of toll-like receptor 3 (TLR3), and a decrease of protein kinase R (PKR) and dsRNA helicases (RIG-I and MDA5) in thymoma from MG patients. We also detected a decreased expression of p53, the tumor suppressor that is known to be down-regulated by dsRNA. Altogether, these results strongly suggest that MG-T could be linked to a viral infection. As p16 (CDKN2A), a marker of HPV infections, was up-regulated in MG-T, we thus screened DNA from thymomas for human papillomavirus (HPV) by real-time PCR using HPV consensus SPF10 primers. RT-PCR results were negative for all samples tested. We confirmed the absence of HPV DNA detection by end point PCR using FAP primers to amplify a larger panel of HPV genotypes. Our data clearly demonstrate INF-I overexpression together with the activation of innate immunity pathways in thymoma-associated MG suggesting that MG might develop after a pathogen infection. We were not able to relate thymoma to HPV infections and the implication of other pathogens is discussed.


Assuntos
Alphapapillomavirus/imunologia , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Interferon Tipo I/metabolismo , Miastenia Gravis/imunologia , Infecções por Papillomavirus/imunologia , Timoma/imunologia , Neoplasias do Timo/imunologia , Adulto , Idoso , Alphapapillomavirus/genética , Anticorpos Antivirais/metabolismo , Autoanticorpos/metabolismo , Células Cultivadas , Pré-Escolar , Inibidor p16 de Quinase Dependente de Ciclina/genética , DNA Viral/análise , Feminino , Regulação da Expressão Gênica , Humanos , Imunidade Inata , Lactente , Recém-Nascido , Interferon Tipo I/genética , Interferon Tipo I/imunologia , Masculino , Pessoa de Meia-Idade , Miastenia Gravis/etiologia , Miastenia Gravis/genética , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/genética , Receptores Colinérgicos/imunologia , Timoma/etiologia , Timoma/genética , Neoplasias do Timo/etiologia , Neoplasias do Timo/genética , Adulto Jovem
15.
Proc Natl Acad Sci U S A ; 108(15): 6217-22, 2011 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-21444793

RESUMO

Cytokine immunotherapies targeting T lymphocytes are attractive clinical interventions against viruses and tumors. In the mouse, the homeostasis of memory α/ß CD8(+) T cells and natural killer (NK) cells is significantly improved with increased IL-15 bioavailability. In contrast, the role of "transpresented" IL-15 on human T-cell development and homeostasis in vivo is unknown. We found that both CD8 and CD4 T cells in human immune system (HIS) mice are highly sensitive to transpresented IL-15 in vivo, with both naïve (CD62L(+)CD45RA(+)) and memory phenotype (CD62L(-)CD45RO(+)) subsets being significantly increased following IL-15 "boosting." The unexpected global improvement in human T-cell homeostasis involved enhanced proliferation and survival of both naïve and memory phenotype peripheral T cells, which potentiated B-cell responses by increasing the frequency of antigen-specific responses following immunization. Transpresented IL-15 did not modify T-cell activation patterns or alter the global T-cell receptor (TCR) repertoire diversity. Our results indicate an unexpected effect of IL-15 on human T cells in vivo, in particular on CD4(+) T cells. As IL-15 promotes human peripheral T-cell homeostasis and increases the frequency of neutralizing antibody responses in HIS mice, IL-15 immunotherapy could be envisaged as a unique approach to improve vaccine responses in the clinical setting.


Assuntos
Formação de Anticorpos/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Interleucina-15/imunologia , Animais , Proliferação de Células , Humanos , Camundongos , Camundongos Mutantes , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Receptores de Interleucina-15/antagonistas & inibidores
16.
Methods Mol Biol ; 2769: 15-25, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38315386

RESUMO

Diethylnitrosamine (DEN) is a chemical hepatocarcinogenic agent that triggers a large array of oncogenic mutations after a single injection. Initiated hepatocytes subsequently undergo clonal expansion within a proliferative environment, rendering the DEN model a comprehensive carcinogen. In rodent studies, DEN finds extensive utility in experimental liver cancer research, mimicking several aspects of human hepatocellular carcinoma (HCC), including angiogenesis, metabolic reprogramming, immune exhaustion, and the ability to metastasize. Beyond the wealth of scientific insights gleaned from this model, the objective of this chapter is to review morphological, genomic, and immunological characteristics associated to DEN-induced HCC. Furthermore, this chapter provides a detailed procedural guide to effectively induce hepatocarcinogenesis in mice through a single intraperitoneal injection of DEN.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Camundongos , Humanos , Animais , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Dietilnitrosamina/toxicidade , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Carcinogênese/induzido quimicamente , Carcinogênese/genética , Hepatócitos/patologia , Camundongos Endogâmicos C57BL
17.
Methods Mol Biol ; 2769: 129-141, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38315394

RESUMO

Tissue-resident and recruited immune cells are essential mediators of natural and therapy-induced immunosurveillance of liver neoplasia. This idea has been recently reinforced by the clinical approval of immune checkpoint inhibitors for the immunotherapy of hepatocellular carcinoma and cholangiocarcinoma. Such research progress relies on the in-depth characterization of the immune populations that are present in pre-neoplastic and neoplastic hepatic lesions. A convenient technology for advancing along this path is high-dimensional cytometry.In this chapter, we present a protocol to assess the subtype and differentiation state of hepatic lymphocyte populations by multicolor immunofluorescence staining and flow cytometry. We detail the steps required for viability assessment and immune cell phenotyping of single-cell suspensions of liver cells by means of surface and intracellular staining of more than a dozen markers of interest. This protocol does not require prior removal of debris and dead cells and allows to process multiple samples in parallel. The procedure includes the use of a fixative-resistant viability dye that allows cell fixation and permeabilization after cell surface staining and before intracellular staining and data acquisition on a flow cytometer. Moreover, we provide a panel of fluorochrome-labeled antibodies designed for the characterization of lymphocytic subsets that can be adapted to distinct experimental settings. Finally, we present an overview of the post-staining pipeline, including data acquisition on a flow cytometer and tools for post-acquisition analyses.


Assuntos
Neoplasias dos Ductos Biliares , Neoplasias Hepáticas , Humanos , Citometria de Fluxo/métodos , Subpopulações de Linfócitos , Ductos Biliares Intra-Hepáticos
18.
J Hepatol ; 59(2): 285-91, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23542345

RESUMO

BACKGROUND & AIMS: Conflicting results have been reported regarding the impact of hepatitis B virus X protein (HBx) expression on liver regeneration triggered by partial hepatectomy (PH). In the present report we investigated the mechanisms by which HBx protein alters hepatocyte proliferation after PH. METHODS: PH was performed on a transgenic mouse model in which HBx expression is under the control of viral regulatory elements and liver regeneration was monitored. LPS, IL-6 neutralizing antibody, and SB203580 were injected after PH to evaluate IL-6 participation during liver regeneration. RESULTS: Cell cycle progression of hepatocytes was delayed in HBx transgenic mice compared to WT animals. Moreover, HBx induced higher secretion of IL-6 soon after PH. Upregulation of IL-6 was associated with an elevation of STAT3 phosphorylation, SOCS3 transcript accumulation and a decrease in ERK1/2 phosphorylation in the livers of HBx transgenic mice. The involvement of IL-6 overexpression in cell cycle deregulation was confirmed by the inhibition of liver regeneration in control mice after the upregulation of IL-6 expression using LPS. In addition, IL-6 neutralization with antibodies was able to restore liver regeneration in HBx mice. Finally, the direct role of p38 in IL-6 secretion after PH was demonstrated using SB203580, a pharmacological inhibitor. CONCLUSIONS: HBx is able to induce delayed hepatocyte proliferation after PH, and HBx-induced IL-6 overexpression is involved in delayed liver regeneration. By modulating IL-6 expression during liver proliferation induced by stimulation of the cellular microenvironment, HBx may participate in cell cycle deregulation and progression of liver disease.


Assuntos
Interleucina-6/fisiologia , Regeneração Hepática/fisiologia , Transativadores/fisiologia , Animais , Anticorpos Neutralizantes/administração & dosagem , Ciclo Celular , Proliferação de Células , Elementos Facilitadores Genéticos , Hepatectomia , Vírus da Hepatite B/genética , Vírus da Hepatite B/patogenicidade , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/imunologia , Hepatite B Crônica/patologia , Hepatite B Crônica/virologia , Hepatócitos/imunologia , Hepatócitos/patologia , Hepatócitos/virologia , Interações Hospedeiro-Patógeno , Humanos , Imidazóis/administração & dosagem , Interleucina-6/antagonistas & inibidores , Regeneração Hepática/genética , Regeneração Hepática/imunologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Modelos Animais , Regiões Promotoras Genéticas , Piridinas/administração & dosagem , Transativadores/genética , Proteínas Virais Reguladoras e Acessórias
19.
J Clin Microbiol ; 51(5): 1428-33, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23426922

RESUMO

Hepatitis C virus (HCV) protease inhibitor resistance-associated substitutions are selected during triple-therapy breakthrough. This multicenter quality control study evaluated the expertise of 23 French laboratories in HCV protease inhibitor resistance genotyping. A panel of 12 well-defined blinded samples comprising two wild-type HCV strains, nine transcripts from synthetic NS3 mutant samples or from clinical strains, and one HCV RNA-negative sample was provided to the participating laboratories. The results showed that any laboratory with expertise in sequencing techniques should be able to provide reliable HCV protease inhibitor resistance genotyping. Only a 0.7% error rate was reported for the amino acid sites studied. The accuracy of substitution identification ranged from 75% to 100%, depending on the laboratory. Incorrect results were mainly related to the methodology used. The results could be improved by changing the primers and modifying the process in order to avoid cross-contamination. This study underlines the value of quality control programs for viral resistance genotyping, which is required prior to launching observational collaborative multicenter studies on HCV resistance to direct-acting antiviral agents.


Assuntos
Antivirais/farmacologia , Farmacorresistência Viral/genética , Hepacivirus/efeitos dos fármacos , Hepacivirus/genética , Inibidores de Proteases/farmacologia , Proteínas não Estruturais Virais/genética , Sequência de Aminoácidos , Antivirais/química , Sequência de Bases , Genótipo , Hepacivirus/enzimologia , Mutação , Inibidores de Proteases/química , Controle de Qualidade , Análise de Sequência de DNA
20.
Clin Exp Med ; 23(1): 87-96, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35199231

RESUMO

The incidence of oropharyngeal cancers (OPC) is increasing in the world. Among OPC, those induced by human papillomaviruses have a better prognosis than non-HPV-associated OPC. The objective of this study was to highlight the relevance of HPV16 load, HPV16 DNA integration and HPV16-L1 serology on progression-free survival and overall survival of OPC patients. The PAPILLOPHAR cohort consists of 362 patients with oropharyngeal squamous cell carcinomas prospectively followed up for 5 years after treatment. Tumor biopsies and sera were collected at inclusion to investigate tumor HPV DNA/RNA characteristics and HPV16 L1 serology, respectively. Twenty-seven percent of tumor biopsies were HPV DNA- and RNA-positive and HPV16 represented 93% of HPV-positive cases. Among them, neither HPV16 viral load nor HPV16 DNA integration was associated with overall survival (OS) or progression-free survival (PFS). In contrast, high anti-HPV16 L1 antibody titers were significantly associated with a better OS and PFS. This study reveals that HPV16 load and integration are not relevant prognosis biomarkers in OPC patients.Clinical Relevance: High levels of HPV16 L1 antibodies may be useful to predict OPC patient outcome following treatment.ClinicalTrials.gov Identifier: NCT00918710, May 2017.


Assuntos
Papillomavirus Humano 16 , Neoplasias Orofaríngeas , Humanos , Papillomavirus Humano 16/genética , Anticorpos Antivirais , Neoplasias Orofaríngeas/patologia , Prognóstico , DNA Viral/genética
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