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1.
J Hepatol ; 54(6): 1185-94, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21145827

ABSTRACT

BACKGROUND & AIMS: C/EBPbeta is an important mediator of several cellular processes, such as differentiation, proliferation, and survival of hepatic cells. However, a complete catalog of the targets of C/EBPbeta or the mechanism by which this transcription factor regulates certain liver-dependent pathways has not been clearly determined. Two major natural isoforms of this transcription factor exist: the liver-enriched activating protein (LAP) and the liver-enriched inhibitory protein (LIP), a functional LAP antagonist. In this study, we used the opposing transcriptional effects driven by LAP and LIP to determine the genuine C/EBPbeta molecular signature in the Hep3B human hepatoma cell line. We subsequently investigated the role of each of the LAP and LIP isoforms in drug-induced Hep3B cell death. METHODS: We engineered Hep3B cells with regulated LAP or LIP expression using the Tet-off expression system. The genes that showed inverse regulation by LAP and LIP were identified by cDNA array analysis. The cohort of direct-C/EBPbeta-targets was distinguished from indirect-targets by ChIP-on-chip analysis. RESULTS: We characterized 676 genes by this approach. Among these genes, 39 are novel direct targets of C/EBPbeta. Eleven of these new direct targets are involved in cell survival, suggesting critical roles for LAP/LIP isoforms in this cellular process. Therefore, we examined the effects of LAP and LIP over-expression on cell survival. We show that LIP promotes survival in staurosporine- or taxol-induced Hep3B cell death. CONCLUSIONS: Our study provides new molecular and cellular insights into the role of C/EBPbeta in cells of hepatic origin.


Subject(s)
CCAAT-Enhancer-Binding Protein-beta/genetics , Carcinoma, Hepatocellular/genetics , Liver Neoplasms/genetics , CCAAT-Enhancer-Binding Protein-beta/physiology , Carcinoma, Hepatocellular/pathology , Cell Death/drug effects , Cell Death/genetics , Cell Death/physiology , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Cell Survival/genetics , Cell Survival/physiology , Gene Expression Profiling , Genetic Engineering , Humans , Liver Neoplasms/pathology , Models, Biological , Oligonucleotide Array Sequence Analysis , Paclitaxel/pharmacology , Protein Isoforms/genetics , Protein Isoforms/physiology , Staurosporine/pharmacology , Transcription, Genetic
2.
Rheumatology (Oxford) ; 50(2): 283-92, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21059672

ABSTRACT

OBJECTIVES: The overall non-response rate to biologics remains 30-40% for patients with RA resistant to MTX. The objective of this study was to predict responsiveness to the anakinra-MTX combination by peripheral blood mononuclear cell gene profiling in order to optimize treatment choice. METHODS: Thirty-two patients treated with anakinra (100 mg/day s.c.) and MTX were categorized as responders when their 28-joint DAS (DAS-28) had decreased by ≥1.2 at 3 months. Pre-treatment blood samples had been drawn. RESULTS: For seven responders and seven non-responders, 52 microarray-identified mRNAs were expressed as a function of the response to treatment, and unsupervised hierarchical clustering correctly separated responders from non-responders. The levels of seven of these 52 transcripts, as assessed by real-time, quantitative RT-PCR, were able to accurately classify 15 of 18 other patients (8 responders and 10 non-responders), with 87.5% specificity and 77.8% negative-predictive value for responders. Among the 52 genes, 56% were associated with IL-1ß. CONCLUSION: This predictive gene expression profile was obtained with a non-invasive procedure. After further validation in other cohorts of patients, it could be proposed and used on a large scale to select likely RA responders to combined anakinra-MTX. Trial registration. Clinical Trials; NCT00213538 (http://www.clinicaltrials.gov).


Subject(s)
Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/drug therapy , Gene Expression Profiling , Interleukin 1 Receptor Antagonist Protein/administration & dosage , Methotrexate/administration & dosage , Adult , Aged , Arthritis, Rheumatoid/genetics , Drug Therapy, Combination , Female , Humans , Male , Middle Aged , Treatment Outcome , Validation Studies as Topic
3.
Arthritis Res Ther ; 11(3): R99, 2009.
Article in English | MEDLINE | ID: mdl-19563633

ABSTRACT

INTRODUCTION: Rheumatoid arthritis (RA) is a heterogeneous disease and its underlying molecular mechanisms are still poorly understood. Because previous microarray studies have only focused on long-standing (LS) RA compared to osteoarthritis, we aimed to compare the molecular profiles of early and LS RA versus control synovia. METHODS: Synovial biopsies were obtained by arthroscopy from 15 patients (4 early untreated RA, 4 treated LS RA and 7 controls, who had traumatic or mechanical lesions). Extracted mRNAs were used for large-scale gene-expression profiling. The different gene-expression combinations identified by comparison of profiles of early, LS RA and healthy synovia were linked to the biological processes involved in each situation. RESULTS: Three combinations of 719, 116 and 52 transcripts discriminated, respectively, early from LS RA, and early or LS RA from healthy synovia. We identified several gene clusters and distinct molecular signatures specifically expressed during early or LS RA, thereby suggesting the involvement of different pathophysiological mechanisms during the course of RA. CONCLUSIONS: Early and LS RA have distinct molecular signatures with different biological processes participating at different times during the course of the disease. These results suggest that better knowledge of the main biological processes involved at a given RA stage might help to choose the most appropriate treatment.


Subject(s)
Arthritis, Rheumatoid/genetics , Arthritis, Rheumatoid/pathology , Gene Expression Profiling/methods , Synovial Fluid/chemistry , Synovial Fluid/physiology , Adult , Arthritis, Rheumatoid/metabolism , Female , Genetic Markers/genetics , Humans , Male , Microarray Analysis/methods , Middle Aged , Synovial Fluid/metabolism , Time Factors , Young Adult
4.
Rheumatology (Oxford) ; 48(9): 1021-8, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19483089

ABSTRACT

This review briefly recapitulates the existing markers predictive of RA responsiveness to treatment, focusing on MTX alone or combined with a biologic. In addition to the demographic and clinical factors, an update is provided of the predictive biomarkers identified by large-scale gene and protein analyses that generated new insights into the ability of high-throughput analysis of biological systems to select new potential indicators. Among the large-scale analysis tools now available, pharmacogenetics and pharmacogenomics (including transcriptomic and proteomic approaches) have been shown to provide such new putative biomarkers of therapeutic responses.


Subject(s)
Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/drug therapy , Immunologic Factors/therapeutic use , Methotrexate/therapeutic use , Arthritis, Rheumatoid/genetics , Biomarkers/blood , Drug Therapy, Combination , Humans , Pharmacogenetics , Prognosis , Treatment Outcome
5.
Am J Pathol ; 175(1): 46-53, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19477948

ABSTRACT

Liver biopsy is considered the gold-standard method for the assessment of liver fibrosis during follow-up of hepatitis C virus-infected patients, but this invasive procedure is not devoid of complications. The aim of the present study was to identify novel non-invasive markers of fibrosis progression. By microarray analysis, we compared transcript levels in two extreme stages of fibrosis from 16 patients. Informative transcripts were validated by real-time PCR and used for the assessment of fibrosis in 23 additional patients. Sixteen transcripts were found to be dysregulated during the fibrogenesis process. Among them, some were of great interest because their corresponding proteins could be serologically measured. Thus, the protein levels of inter-alpha inhibitor H1, serpin peptidase inhibitor clade F member 2, and transthyretin were all significantly different according to the four Metavir stages of fibrosis. In conclusion, we report here that dysregulation, at both the transcriptional and protein levels, exists during the fibrogenesis process. Our description of three novel serum markers and their potential use as serological tests for the non-invasive diagnosis of liver fibrosis open new opportunities for better follow-up of hepatitis C virus-infected patients.


Subject(s)
Biomarkers/blood , Hepatitis C/blood , Hepatitis C/pathology , Liver Cirrhosis/blood , Liver Cirrhosis/pathology , Alpha-Globulins/biosynthesis , Alpha-Globulins/genetics , Blotting, Western , Disease Progression , Female , Hepacivirus , Hepatitis C/genetics , Humans , Liver Cirrhosis/virology , Male , Middle Aged , Oligonucleotide Array Sequence Analysis , Prealbumin/biosynthesis , Prealbumin/genetics , Reverse Transcriptase Polymerase Chain Reaction , Transcription, Genetic , alpha-2-Antiplasmin/biosynthesis , alpha-2-Antiplasmin/genetics
6.
Histopathology ; 54(3): 319-27, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19236508

ABSTRACT

AIMS: Hepatocellular carcinoma (HCC) results from cirrhosis and, in Western Europe, hepatitis C virus and alcoholism are the predominant causes of this disease. We recently documented a global transcript repression in hepatocarcinoma nodules. The tumour suppressor activated pathway-6 (TSAP6) transcript codes for a transmembrane molecule that is an inducer of a caspase-3-dependent apoptotic pathway. The down-regulation of TSAP6 transcripts in HCC and perinodular cirrhosis, which contrasts with a sustained transcript level in HCC-free cirrhosis, has suggested that this hepatic protein level may provide a prognostic marker for HCC occurrence. METHODS AND RESULTS: This protein was quantified by semiquantitative assessment of immunohistochemistry on samples from 42 cases HCC-free cirrhosis, 49 cases cirrhosis with HCC, 43 HCC associated with healthy liver and 31 controls. TSAP6 expression was linked to the liver state, healthy or cirrhotic without or with an HCC and to tumour grade. CONCLUSIONS: With biopsies periodically performed for surveillance purposes, the decreased expression of TSAP6 in cirrhotic tissue could reflect a decrease in the apoptotic process and could be interpreted as a warning sign. This evaluation of the TSAP6 level in cirrhotic liver conveys predictive information for the development of HCC.


Subject(s)
Carcinoma, Hepatocellular/pathology , Down-Regulation/genetics , Liver Cirrhosis/pathology , Liver Neoplasms/pathology , Liver/pathology , Oncogene Proteins/genetics , Carcinoma, Hepatocellular/genetics , Cell Cycle Proteins , Gene Expression , Immunohistochemistry , Liver/metabolism , Liver Cirrhosis/genetics , Liver Neoplasms/genetics , Oncogene Proteins/metabolism , Oxidoreductases
7.
World J Gastroenterol ; 15(3): 300-9, 2009 Jan 21.
Article in English | MEDLINE | ID: mdl-19140229

ABSTRACT

AIM: To search for transcription dysregulation that could (1) differentiate hepatocellular carcinoma (HCC)-free from HCC-related cirrhosis (2) differentiate HCC-free cirrhosis related to HCV from that related to alcohol intake. METHODS: Using microarray analysis, we compared transcript levels in HCC-free cirrhosis (alcoholism: 7; hepatitis C: 7), HCC-associated cirrhosis (alcoholism: 10; hepatitis C: 10) and eight control livers. The identified transcripts were validated by qRT-PCR in an independent cohort of 45 samples (20 HCC-free cirrhosis; 15 HCC-associated cirrhosis and 10 control livers). We also confirmed our results by immunohistochemistry. RESULTS: In HCC-free livers, we identified 70 transcripts which differentiated between alcoholic-related cirrhosis, HCV-related cirrhosis and control livers. They mainly corresponded to down-regulation. Dysregulation of Signal Transduction and Activator of Transcription-3 (STAT-3) was found along with related changes in STAT-3 targets which occurred in an etiology-dependent fashion in HCC-free cirrhosis. In contrast, in HCC, such transcription dysregulations were not observed. CONCLUSION: We report that transcriptional dysregulations exist in HCC-free cirrhosis, are transiently observed prior to detectable HCC onset and may be appear like markers from cirrhosis to HCC transition.


Subject(s)
Carcinoma, Hepatocellular/genetics , Gene Expression Regulation, Neoplastic , Liver Cirrhosis/etiology , Liver Cirrhosis/genetics , Liver Neoplasms/genetics , Transcription, Genetic , Adult , Aged , Carcinoma, Hepatocellular/pathology , Female , Gene Expression Profiling , Gene Regulatory Networks , Humans , Liver Cirrhosis/pathology , Liver Neoplasms/pathology , Male , Middle Aged , Oligonucleotide Array Sequence Analysis , Plasminogen/genetics , Plasminogen/metabolism
8.
World J Gastroenterol ; 14(11): 1749-58, 2008 Mar 21.
Article in English | MEDLINE | ID: mdl-18350606

ABSTRACT

AIM: To look at a comprehensive picture of etiology-dependent gene abnormalities in hepatocellular carcinoma in Western Europe. METHODS: With a liver-oriented microarray, transcript levels were compared in nodules and cirrhosis from a training set of patients with hepatocellular carcinoma (alcoholism, 12; hepatitis C, 10) and 5 controls. Loose or tight selection of informative transcripts with an abnormal abundance was statistically valid and the tightly selected transcripts were next quantified by qRTPCR in the nodules from our training set (12 + 10) and a test set (6 + 7). RESULTS: A selection of 475 transcripts pointed to significant gene over-representation on chromosome 8 (alcoholism) or -2 (hepatitis C) and ontology indicated a predominant inflammatory response (alcoholism) or changes in cell cycle regulation, transcription factors and interferon responsiveness (hepatitis C). A stringent selection of 23 transcripts whose differences between etiologies were significant in nodules but not in cirrhotic tissue indicated that the above dysregulations take place in tumor but not in the surrounding cirrhosis. These 23 transcripts separated our test set according to etiologies. The inflammation-associated transcripts pointed to limited alterations of free iron metabolism in alcoholic vs hepatitis C tumors. CONCLUSION: Etiology-specific abnormalities (chromo-some preference; differences in transcriptomes and related functions) have been identified in hepatocellular carcinoma driven by alcoholism or hepatitis C. This may open novel avenues for differential therapies in this disease.


Subject(s)
Carcinoma, Hepatocellular/genetics , Gene Expression Regulation, Neoplastic , Hepatitis C/complications , Liver Cirrhosis, Alcoholic/complications , Liver Cirrhosis/complications , Liver Neoplasms/genetics , Adult , Aged , Carcinoma, Hepatocellular/virology , Chromosomes, Human, Pair 2 , Chromosomes, Human, Pair 8 , Cluster Analysis , Female , Gene Expression Profiling/methods , Hepatitis C/genetics , Humans , Liver Cirrhosis/genetics , Liver Cirrhosis/virology , Liver Cirrhosis, Alcoholic/genetics , Liver Neoplasms/virology , Male , Middle Aged , Oligonucleotide Array Sequence Analysis , Polymerase Chain Reaction , RNA, Messenger/analysis , Reproducibility of Results
9.
World J Gastroenterol ; 13(20): 2833-40, 2007 May 28.
Article in English | MEDLINE | ID: mdl-17569119

ABSTRACT

AIM: To evaluate the effect of glutamine on intestinal mucosa integrity, glutathione stores and acute phase response in protein-depleted rats during an inflammatory shock. METHODS: Plasma acute phase proteins (APP), jejunal APP mRNA levels, liver and jejunal glutathione concentrations were measured before and one, three and seven days after turpentine injection in 4 groups of control, protein-restricted, protein-restricted rats supplemented with glutamine or protein powder. Bacterial translocation in mesenteric lymph nodes and intestinal morphology were also assessed. RESULTS: Protein deprivation and turpentine injection significantly reduced jejunal villus height, and crypt depths. Mucosal glutathione concentration significantly decreased in protein-restricted rats. Before turpentine oil, glutamine supplementation restored villus heights and glutathione concentration (3.24 +/- 1.05 vs 1.72 +/- 0.46 mumol/g tissue, P<0.05) in the jejunum, whereas in the liver glutathione remained low. Glutamine markedly increased jejunal alpha1-acid glycoprotein mRNA level after turpentine oil but did not affect its plasma concentration. Bacterial translocation in protein-restricted rats was not prevented by glutamine or protein powder supplementation. CONCLUSION: Glutamine restored gut glutathione stores and villus heights in malnourished rats but had no preventive effect on bacterial translocation in our model.


Subject(s)
Acute-Phase Reaction/metabolism , Glutamine/metabolism , Glutathione/metabolism , Inflammatory Bowel Diseases/metabolism , Intestinal Mucosa/drug effects , Malnutrition/metabolism , Acute-Phase Proteins/genetics , Acute-Phase Proteins/metabolism , Animals , Bacterial Translocation/drug effects , Blood Proteins/genetics , Blood Proteins/metabolism , Dietary Supplements , Disease Models, Animal , Glutamine/administration & dosage , Glutathione/administration & dosage , Glycoproteins/genetics , Glycoproteins/metabolism , Inflammatory Bowel Diseases/microbiology , Intestinal Mucosa/metabolism , Intestinal Mucosa/pathology , Irritants/adverse effects , Liver/metabolism , Male , Orosomucoid , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rats , Rats, Sprague-Dawley , Turpentine/adverse effects
10.
Arthritis Res Ther ; 8(4): R105, 2006.
Article in English | MEDLINE | ID: mdl-16817978

ABSTRACT

As indicators of responsiveness to a tumour necrosis factor (TNF)alpha blocking agent (infliximab) are lacking in rheumatoid arthritis, we have used gene profiling in peripheral blood mononuclear cells to predict a good versus poor response to infliximab. Thirty three patients with very active disease (Disease Activity Score 28 >5.1) that resisted weekly methotrexate therapy were given infliximab at baseline, weeks 2 and 6, and every 8th week thereafter. The patients were categorized as responders if a change of Disease Activity Score 28 = 1.2 was obtained at 3 months. Mononuclear cell RNAs were collected at baseline and at three months from responders and non-responders. The baseline RNAs were hybridised to a microarray of 10,000 non-redundant human cDNAs. In 6 responders and 7 non-responders, 41 mRNAs identified by microarray analysis were expressed as a function of the response to treatment and an unsupervised hierarchical clustering perfectly separated these responders from non-responders. The informativeness of 20 of these 41 transcripts, as measured by qRT-PCR, was re-assessed in 20 other patients. The combined levels of these 20 transcripts properly classified 16 out of 20 patients in a leave-one-out procedure, with a sensitivity of 90% and a specificity of 70%, whereas a set of only 8 transcripts properly classified 18/20 patients. Trends for changes in various transcript levels at three months tightly correlated with treatment responsiveness and a down-regulation of specific transcript levels was observed in non-responders only. Our gene profiling obtained by a non-invasive procedure should now be used to predict the likely responders to an infliximab/methotrexate combination.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/blood , Arthritis, Rheumatoid/drug therapy , Gene Expression Profiling , Monocytes/metabolism , Adult , Aged , Female , Follow-Up Studies , Humans , Infliximab , Male , Middle Aged , Oligonucleotide Array Sequence Analysis , Predictive Value of Tests , RNA, Messenger/blood , Time Factors , Treatment Outcome , Tumor Necrosis Factor-alpha/antagonists & inhibitors
11.
Hepatology ; 42(4): 946-55, 2005 Oct.
Article in English | MEDLINE | ID: mdl-16175611

ABSTRACT

Given the unknown timing of the onset of an acute systemic inflammation in humans, the fine tuning of cascades and pathways involved in the associated hepatocyte response cannot be appraised in vivo. Therefore, the authors used a genome-wide and kinetic analysis in the human Hep3B hepatoma cell line challenged with a conditioned medium from bacterial lipopolysaccharide-stimulated macrophages. A complete coverage of the liver transcriptome disclosed 648 mRNAs whose change in abundance allowed for their clustering in mRNA subsets with an early, intermediate, or late regulation. The contribution of transcription, stability, or translation was appraised with genome-wide studies of the changes in nuclear primary transcripts, mRNA decay, or polysome-associated mRNAs. A predominance of mRNAs with decreased stability and the fact that translation alone controls a significant number of acute phase-associated proteins are prominent findings. Transcription and stability act independently or, more rarely, cooperate or even counteract in a gene-by-gene manner, which results in a unidirectional change in mRNA abundance. Waves of mRNAs for groups of functionally related proteins are up- or downregulated in an ordered fashion. This includes an early regulation of transcription-associated proteins, an intermediate repression of detoxication and metabolism proteins, and finally an enhanced translation and transport of a number of membranous or secreted proteins along with an enhanced protein degradation. In conclusion, this study provides a comprehensive and simultaneous overview of events in the human hepatocyte during the inflammatory acute phase.


Subject(s)
Cytokines/immunology , Genomics , Hepatocytes/immunology , Hepatocytes/physiology , Oligonucleotide Array Sequence Analysis , Acute-Phase Reaction/genetics , Carcinoma, Hepatocellular , Cell Line, Tumor , Genome, Human , Humans , Kinetics , Liver Neoplasms , Polyribosomes/physiology , Protein Biosynthesis/genetics , Protein Biosynthesis/immunology , RNA Stability , RNA, Messenger/metabolism , Transcription, Genetic/genetics , Transcription, Genetic/immunology
12.
J Hepatol ; 42(6): 860-9, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15885357

ABSTRACT

BACKGROUND/AIMS: Whether the transcriptional reprogramming process induced by hepatocellular carcinoma recapitulates that of the developing liver is at present unclear. METHODS: With a complete coverage of the liver transcriptome by microarray using adult livers as controls, we searched for similarities and differences in mRNA abundances between hepatocellular carcinoma nodules and fetal livers taken before (early) or after (late) the 22-24th week of gestation. Changes in some mRNA levels were studied in further liver samples by quantitative RT-PCR. RESULTS: Altered gene expression in hepatocellular carcinoma mostly results in down-regulated mRNAs which largely overlap with those repressed in the late fetal liver. Different frequencies of transcription factor binding sites in the down-regulated genes vs control genes as well as changes in abundance of mRNAs for relevant transcription factors point to a transcriptional repression. The down-regulated mRNAs code for proteins involved in (i) transcription and translation, (ii) specific functions of the differentiated hepatocyte or (iii) activation of proliferation and apoptosis. CONCLUSIONS: Apoptosis limitation is likely to predominate over active proliferation during liver development and hepatocellular carcinoma. Repression of the apoptosis-associated dudulin-2 mRNA points to a potential marker for the transition from a carcinoma-free to carcinoma-associated cirrhosis.


Subject(s)
Carcinoma, Hepatocellular/genetics , Gene Expression Regulation, Developmental , Gene Expression Regulation, Neoplastic , Liver Neoplasms/genetics , Liver/physiology , Oncogene Proteins/genetics , Aged , Aged, 80 and over , Binding Sites/genetics , Biomarkers, Tumor/genetics , Cell Cycle Proteins , Down-Regulation/genetics , Female , Humans , Liver/embryology , Liver Cirrhosis/genetics , Male , Middle Aged , Oligonucleotide Array Sequence Analysis , Oxidoreductases , RNA, Messenger/analysis , Reverse Transcriptase Polymerase Chain Reaction
13.
JPEN J Parenter Enteral Nutr ; 29(1): 48-55, 2005.
Article in English | MEDLINE | ID: mdl-15715274

ABSTRACT

BACKGROUND: Kupffer cells (KCs) are the resident macrophages of the liver. KCs have an enormous endotoxin eliminating capacity. Endotoxins play an important role in the development of systemic complications after partial hepatectomy by activating KCs. The role of KCs and endotoxins after partial hepatectomy is investigated. METHODS: Wistar rats (n = 16, 250-275 g) were randomly assigned to have 1 mL dichloromethylene-diphosphonate (CL2MDP) or 1 mL NaCl 0.9% i.v. Forty-eight hours later, all rats received a two-thirds liver resection. Twenty-four hours later, rats received at random 50 microg/kg endotoxin (LPS) in 1 mL or 1 mL of NaCl 0.9% IV. The rats were killed 4 hours after LPS or SAL infusion. RESULTS: CL2MDP infusion resulted in a complete KC elimination. KC-depleted rats had the lowest mean arterial pressure, the highest heart and ventilatory rate after endotoxemia. All rats were able to maintain pH in normal ranges. The KC-depleted rats after partial hepatectomy had the lowest CO2 levels and the highest levels of lactate during endotoxemia. Oxygen levels were similar in all groups. Hepatic, pulmonary, and renal mRNA expression of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta were decreased in KC-depleted rats. Plasma levels of TNF-alpha were significantly decreased in KC-depleted rats. Furthermore, the highest influx of macrophages and polymorphonuclear cells in the lung and kidney were measured in KC-depleted rats during endotoxemia. CONCLUSIONS: Partial hepatectomy in KC-depleted rats result in a more pronounced endotoxin-mediated systemic inflammation and decreased synthesis of cytokines.


Subject(s)
Endotoxins/administration & dosage , Hepatectomy , Kupffer Cells/physiology , Liver/immunology , Liver/surgery , Animals , Clodronic Acid/pharmacology , Cytokines/biosynthesis , Endotoxins/toxicity , Kupffer Cells/immunology , Macrophages/drug effects , Macrophages/immunology , Male , Postoperative Complications , Random Allocation , Rats , Rats, Wistar , Specific Pathogen-Free Organisms
14.
J Immunol ; 173(5): 3418-24, 2004 Sep 01.
Article in English | MEDLINE | ID: mdl-15322206

ABSTRACT

Activation of the complement system generates the anaphylatoxin C5a whose activities are mediated through its binding to the widely expressed C5aR. C5aR mRNA and protein expressions are known to be induced in rat hepatocytes under inflammatory conditions. However, little is known about the role of the C5a/C5aR complex in liver and its involvement during a proliferative process. We have evaluated the expression of C5aR in regenerating rat hepatocytes following a partial hepatectomy and in hepatocyte cultures. C5aR induction was observed in hepatocytes from regenerating liver, as well as in normal hepatocytes under a culture-induced stress. The effect of a stimulation by a C5a agonist upon the synthesis of a growth factor/receptor pair (hepatocyte growth factor/c-Met) was also evaluated. Our data demonstrated an up-regulated expression of hepatocyte growth factor and c-Met mRNAs, but we failed to observe a direct mitogenic effect of C5a in culture. However, a significantly increased expression of cyclin E and D1mRNA levels, as well as an increased BrdU incorporation, were observed in rats given an i.v. C5a agonist injection following an 80% partial hepatectomy. These studies demonstrate for the first time that: 1) C5aR is up-regulated during liver regeneration, 2) the binding of C5a to C5aR promotes a growth response, and 3) C5aR is involved in a cell cycle signaling pathway. Taken together, these findings point to a novel role for the hepatic C5aR implicating this complement system in the context of normal or abnormal proliferative pathways.


Subject(s)
Hepatocytes/metabolism , Liver Regeneration/physiology , Receptor, Anaphylatoxin C5a/metabolism , Signal Transduction/physiology , Animals , Cell Division/physiology , Complement C5a/metabolism , Hepatocyte Growth Factor/metabolism , Hepatocytes/cytology , Hepatocytes/immunology , Inflammation/immunology , Liver/immunology , Liver/surgery , Proto-Oncogene Proteins c-met/metabolism , RNA, Messenger/metabolism , Rats , Receptor, Anaphylatoxin C5a/genetics , Receptor, Anaphylatoxin C5a/immunology
15.
Shock ; 21(6): 561-5, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15167686

ABSTRACT

Partial hepatectomy (PH)-induced Kupffer cell (KC) activation results in a rapid release of cytokines inducing the acute-phase response (APR). This study was done to evaluate the role of Kupffer cells (KCs) in the course of the APR following PH and a consecutive endotoxin challenge. KC depletion was performed in rats by i.v. administration of 1 mL liposome-encapsulated dichloromethylene diphosohonate (Cl2MDP). Control rats received 1 mL NaCl 0.9%. Forty-eight hours later, PH was performed. At 24 h after PH, rats were randomized to receive either 1 mL NaCl 0.9% (saline) or 50 microg/kg LPS i.v. in 1 mL. Animals were sacrificed at 4 h after LPS or saline infusion. The APR was determined by measuring hepatic gene expression of alpha 2-macroglobulin, alpha 1-acid glycoprotein, and IL-6 and expression of hepatic albumin. The APR was significantly depressed in KC-depleted rats. Despite increased IL-6 mRNA synthesis in response to low-dose LPS, no enhancement of acute-phase protein synthesis (APP) was found in KC-depleted rats. Hepatic failure was most profound in KC-depleted rats, as indicated by elevated plasma levels of liver transaminases and ammonia. We conclude that after PH, KC function in the remnant liver is important for the acute-phase reaction and reduces endotoxin-induced hepatocyte damage.


Subject(s)
Acute-Phase Reaction/pathology , Kupffer Cells/physiology , Liver/pathology , Liver/surgery , Acute-Phase Proteins/genetics , Acute-Phase Proteins/metabolism , Albumins/genetics , Albumins/metabolism , Animals , Aspartate Aminotransferases/blood , Clodronic Acid/pharmacology , Dose-Response Relationship, Drug , Endotoxins/administration & dosage , Endotoxins/toxicity , Hepatectomy/methods , Interleukin-6/genetics , Interleukin-6/metabolism , Kupffer Cells/drug effects , Macrophages/drug effects , Male , Orosomucoid/drug effects , Orosomucoid/genetics , Orosomucoid/metabolism , Postoperative Complications/pathology , Quaternary Ammonium Compounds/blood , Rats , Rats, Wistar , Surgical Wound Infection/pathology , alpha-Macroglobulins/drug effects , alpha-Macroglobulins/genetics , alpha-Macroglobulins/metabolism
16.
Hepatology ; 39(2): 353-64, 2004 Feb.
Article in English | MEDLINE | ID: mdl-14767988

ABSTRACT

The goal of the current study was to provide complete coverage of the liver transcriptome with human probes corresponding to every gene expressed in embryonic, adult, and/or cancerous liver. We developed dedicated tools, namely, the Liverpool nylon array of complementary DNA (cDNA) probes for approximately 10,000 nonredundant genes and the LiverTools database. Inflammation-induced transcriptome changes were studied in liver tissue samples from patients with an acute systemic inflammation and from control subjects. One hundred and fifty-four messenger RNAs (mRNA) correlated statistically with the extent of inflammation. Of these, 134 mRNA samples were not associated previously with an acute-phase (AP) response. The hepatocyte origin and proinflammatory cytokine responsiveness of these mRNAs were confirmed by quantitative reverse-transcription polymerase chain reaction (Q-RT-PCR) in cytokine-challenged hepatoma cells. The corresponding gene promoters were enriched in potential binding sites for inflammation-driven transcription factors in the liver. Some of the corresponding proteins may provide novel blood markers of clinical relevance. The mRNAs whose level is most correlated with the AP extent (P <.05) were enriched in intracellular signaling molecules, transcription factors, glycosylation enzymes, and up-regulated plasma proteins. In conclusion, the hepatocyte responded to the AP extent by fine tuning some mRNA levels, controlling most, if not all, intracellular events from early signaling to the final secretion of proteins involved in innate immunity. Supplementary material for this article can be found on the HEPATOLOGY website (http://interscience.wiley.com/jpages/0270-9139/suppmat/index.html).


Subject(s)
Hepatitis/genetics , Oligonucleotide Array Sequence Analysis/methods , Acute Disease , Adult , Aged , Aged, 80 and over , Cytokines/genetics , Databases, Genetic , Female , Gene Expression , Genetic Markers , Hepatitis/immunology , Hepatitis/physiopathology , Hepatocytes/immunology , Hepatocytes/physiology , Humans , Male , Middle Aged , Promoter Regions, Genetic , RNA, Messenger/analysis , Signal Transduction/genetics
17.
Nucleic Acids Res ; 31(20): 5957-70, 2003 Oct 15.
Article in English | MEDLINE | ID: mdl-14530444

ABSTRACT

Fetuin-A is an hepatic protein whose mRNA transiently falls during the inflammatory acute phase via unknown transcriptional mechanisms. Various FETUA promoter/cat constructs transiently transfected in the Hep3B hepatoma cell line allowed us to identify four NF-1 and C/EBP binding sites (N, C) arranged in a 5'-N2-C2-N1-C1-3' order and required for basal promoter activity. Mutant constructs demonstrated that C1 and C2 but not N1 nor N2 are required for the cytokine-driven down-regulation of the promoter. A variable spacing between C2 and N1 showed that the alignment of the (C1+N1) and (C2+N2) areas is critical for the promoter activity in quiescent but not cytokine-stimulated cells. Co-transfection of a plasmid only producing either a long or short C/EBPbeta isoform prevented FETUA regulation by cytokines. Electromobility shift assays with liver nuclear extracts showed that during the acute phase the complexes formed over N1 and N2 are not modified whereas short C/EBPalpha and -beta isoforms replace the long isoforms bound to C1 and C2 in the quiescent liver. Therefore the basal promoter activity requires an interaction between the long C/EBP isoforms bound to C1 and C2 whereas the inflammation-induced down-regulation results from the loss of interaction between the cytokine-induced, short C/EBP isoforms.


Subject(s)
Blood Proteins/metabolism , CCAAT-Enhancer-Binding Proteins/metabolism , Inflammation/physiopathology , Liver/metabolism , Animals , Base Sequence , Binding Sites/genetics , Blood Proteins/genetics , CCAAT-Enhancer-Binding Proteins/genetics , Cell Line, Tumor , Chloramphenicol O-Acetyltransferase/genetics , Chloramphenicol O-Acetyltransferase/metabolism , Cytokines/pharmacology , DNA-Binding Proteins/metabolism , Down-Regulation/drug effects , Humans , Lipopolysaccharides/pharmacology , Liver/drug effects , Mice , Mice, Inbred C57BL , Molecular Sequence Data , NFI Transcription Factors , Promoter Regions, Genetic/genetics , Protein Binding , Protein Isoforms/genetics , Protein Isoforms/metabolism , RNA, Messenger/drug effects , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rats , Rats, Sprague-Dawley , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Response Elements/drug effects , Response Elements/genetics , Sequence Homology, Nucleic Acid , Transcription Factors/metabolism , Transfection , alpha-2-HS-Glycoprotein
18.
Joint Bone Spine ; 70(4): 248-56, 2003 Aug.
Article in English | MEDLINE | ID: mdl-12951306

ABSTRACT

Large-scale analysis of gene expression with cDNA arrays is spreading over many biological fields, including rheumatology. In this report, we wish to explain the principle and main advantages of this tool in the context of our discipline. Until 1995, analysis of gene expression was conducted for a few genes at a time but DNA chips now allow one to monitor the expression of thousands of genes in a single experiment and analyze the transcriptome, i.e. the whole of the transcripts in a given cell or tissue. Whatever the platform used (macro- or microarrays, oligo-chips), this technology rests upon the hybridization of i) a set of cDNA clones tethered to a solid support (nylon or glass) as probes, and ii) labelled cDNAs that are reverse-transcribed from bulk mRNAs extracted from a cell or tissue sample as a target. The end result is information on the relative abundance of every mRNA between two or more samples. The transcriptome analysis has two main objectives in rheumatology: i) identifying a gene expression profile that is a hallmark of a pathology and using it for a diagnostic or prognostic purpose, and ii) gathering genes with similar changes of expression, which allows one to specify the identity of novel proteins involved in a well-known intracellular cascade of regulation or even to identify new cascades.


Subject(s)
Arthritis, Rheumatoid/genetics , Gene Expression Profiling , Oligonucleotide Array Sequence Analysis , Rheumatology/methods , Arthritis, Rheumatoid/diagnosis , Humans , Protein Biosynthesis , Proteomics , Transcription, Genetic
19.
Mol Carcinog ; 36(3): 130-41, 2003 Mar.
Article in English | MEDLINE | ID: mdl-12619035

ABSTRACT

A change in the balance between proliferation and apoptosis in the course of hepatocellular carcinoma (HCC) development and progression has been suspected. We wanted to identify related genes whose mRNA levels could provide markers of severity and prognosis after resection. The extent of cell apoptosis, proliferation, and differentiation was measured with a terminal deoxynucleotidyl transferase-mediated deoxyuridine 5-triphosphate-biotin nick-end labeling assay, and the Ki-67 index was determined in paired tumor and cirrhotic tissue samples from patients who had undergone HCC resection after diagnosis of hepatitis C-related or alcoholism-related cirrhosis. These patients included two groups with highly versus poorly differentiated tumor cells, and the latter was split into two subgroups of those with versus without early recurrence. The mRNA levels for various apoptosis-related or proliferation-related genes and those for the growth factor/receptor systems were measured by quantitative reverse transcriptase-polymerase chain reaction in paired tumor and cirrhotic liver samples from every patient, and some of the corresponding proteins were detected by immunohistochemistry. In all instances, protein expression was highly heterogeneous within groups and similar between groups. In contrast, some differences in mRNA level between tumor and cirrhotic tissues were quite informative. Low levels of hepatocyte growth factor and transforming growth factor alpha mRNAs were found concomitantly in highly differentiated tumors, whereas overexpression of mRNAs for the cognate receptors c-met and epidermal growth factor receptor were found in poorly differentiated tumors and primarily in patients with early tumor recurrence. These results argue for growth factor-dependent HCC development and provide novel and combined prognosis markers after HCC surgery.


Subject(s)
Carcinoma, Hepatocellular/genetics , ErbB Receptors/genetics , Hepatocyte Growth Factor/genetics , Liver Neoplasms/genetics , Proto-Oncogene Proteins c-met/genetics , Transforming Growth Factor alpha/genetics , Aged , Apoptosis/genetics , Biomarkers, Tumor/analysis , Carcinoma, Hepatocellular/diagnosis , Carcinoma, Hepatocellular/pathology , Carcinoma, Hepatocellular/surgery , Female , Gene Expression Regulation , Hepatitis C/complications , Humans , Liver Cirrhosis/etiology , Liver Cirrhosis/pathology , Liver Neoplasms/diagnosis , Liver Neoplasms/pathology , Liver Neoplasms/surgery , Male , Middle Aged , Oncogenes , Prognosis
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