Biomedical subjects

Bruno Mougin

Publications and source records attributed to Bruno Mougin.

12 recordsLinked to original sources

PubMed2006

Rheumatoid arthritis and genetic markers in Syrian and French populations: different effect of the shared epitope.

OBJECTIVE: To investigate whether ethnic differences exist in the effect of the shared epitope and selected cytokine gene polymorphisms on the susceptibility and severity of rheumatoid arthritis in Syria (Damascus) and France (Rhône-Alpes area). METHODS: 156 patients with rheumatoid arthritis and 120 healthy controls from Syria were compared with 512 patients with rheumatoid arthritis and 471 healthy controls from France. Shared epitope status, cytokine gene polymorphisms interleukin (IL)-1B +3954, IL-1RN +2018 and tumour necrosis factor alpha promoter (-238 and -308) were analysed by enzyme-linked oligosorbent assay. Joint destruction was defined by a right wrist Larsen score > or =2. Odds ratios (ORs) were calculated. RESULTS: In both countries, a dose effect was observed between the shared epitope copy number and rheumatoid arthritis (Syria: OR 1 v 0 copies = 1.6, p = NS; OR 2 v 0 = 15.3, p<0.01; and France: OR 1 v 0 = 2.3, p<0.001; OR 2 v 0 = 7.2, p<0.001). A dose effect was also observed between the shared epitope copy number and joint destruction in Syria (OR 1 v 0 = 2.2, p = NS; OR 2 v 0 = 9.9, p<0.01) and France (OR 1 v 0 = 1.8, p<0.01; OR 2 v 0 = 4.8, p = 0.001). The dose effect of the shared epitope was greater in Syria than in France. Only the -238 tumour necrosis factor alpha polymorphism was associated with joint destruction in the Syrian population (p<0.05). However, after adjustment for age, sex, disease duration and rheumatoid factor for severity, this association disappeared. CONCLUSION: The frequency of the shared epitope was increased in the French population with rheumatoid arthritis and in controls, but the association between the shared epitope and joint destruction was more pronounced in the Syrian population, with an OR of almost 10 for the homozygotes.

Adult↗

PubMed2006

Prognostic significance of urokinase plasminogen activator and plasminogen activator inhibitor-1 mRNA expression in lymph node- and hormone receptor-positive breast cancer.

BACKGROUND: One of the most thoroughly studied systems in relation to its prognostic relevance in patients with breast cancer, is the plasminogen activation system that comprises of, among others, the urokinase Plasminogen Activator (uPA) and its main inhibitor, the Plasminogen Activator Inhibitor-1 (PAI-1). In this study, we investigated the prognostic value of uPA and PAI-1 at the mRNA level in lymph node- and hormone receptor-positive breast cancer. METHODS: The study included a retrospective series of 87 patients with hormone-receptor positive and axillary lymph node-positive breast cancer. All patients received radiotherapy, adjuvant anthracycline-based chemotherapy and five years of tamoxifen treatment. The median patient age was 54 and the median follow-up time was 79 months. Distant relapse occurred in 30 patients and 22 patients died from breast cancer during follow-up. We investigated the prognostic value of uPA and PAI-1 at the mRNA level as measured by real-time quantitative RT-PCR. RESULTS: uPA and PAI-1 gene expression was not found to be correlated with any of the established clinical and pathological factors. Metastasis-free Survival (MFS) and Breast Cancer specific Survival (BCS) were significantly shorter in patients expressing high levels of PAI-1 mRNA (p < 0.0001; p < 0.0001; respectively). In Cox multivariate analysis, the level of PAI-1 mRNA appeared to be the strongest prognostic factor for MFS (Hazard Ratio (HR) = 10.12; p = 0.0002) and for BCS (HR = 13.17; p = 0.0003). Furthermore, uPA gene expression was not significantly associated neither with MFS (p = 0.41) nor with BCS (p = 0.19). In a Cox-multivariate regression analysis, uPA expression did not demonstrate significant independent prognostic value. CONCLUSION: These findings indicate that high PAI-1 mRNA expression represents a strong and independent unfavorable prognostic factor for the development of metastases and for breast cancer specific survival in a population of hormone receptor- and lymph node-positive breast cancer patients.

Breast Neoplasms↗

PubMed2006

Systemic transcriptional analysis in survivor and non-survivor septic shock patients: a preliminary study.

The second phase of septic shock is characterized by an anti-inflammatory state and patients rapidly develop features consistent with immunosuppression. The mechanisms sustaining this disease step are far from being well understood. The objective of the present study was to perform a genome-wide survey of mRNA expression in septic shock patients in order to investigate the bases of sepsis-induced immunoparalysis. We used Affymetrix HG-U133A oligonucleotide arrays to compare systemic gene expression patterns of survivors and non-survivors after the first 24 h of the syndrome (n = 38 patients). Supervised analysis identified a set of 28 genes efficiently discriminating non-survivors from survivors with a sensitivity of 100% and a specificity of 86%. The microarray findings were confirmed by qRT-PCR and the ability of the selected probe sets to function as a classifier of outcome was verified with an independent set of additional microarray analyses. Noteworthy, of gene overexpressed in survivors, many are known to participate in innate immunity (cytokine, chemokine receptor, effectors of the Toll-receptor pathways). It supports the hypothesis that restoration of inflammatory/immune functions is a key step for survival after septic shock. The consistency of our results into the context of sepsis-induced immunoparalysis tends to indicate that blood transcriptional profiling is a valuable approach not only for patients stratification but also to identity new genes possibly involved in sepsis pathophysiology.

Aged↗

PubMed2006

Lack of association of IL-10 promoter gene variants with type 1 diabetes in a French population.

Although genetic predisposition to type 1 diabetes shows a strong association with human leukocyte antigen (HLA) class II alleles, additional genes may influence the immune process and the progression of beta cell loss. Preliminary reports suggested that IL-10 gene polymorphisms contribute to susceptibility to type 1 diabetes. We analyzed the frequencies of three main variants of the promoter region of the IL-10 gene at the positions -1082, -819, and -592 in a cohort of 358 type 1 diabetic patients representing the same regional population pattern and 519 controls from the same region using an enzyme-linked oligonucleotide sorbent assay. We did not find any statistical association in the entire cohort or after stratification for high-risk HLA-DQ alleles. However, the IL-10 -1082 polymorphism was significantly associated with GAD and IA-2 antibodies at clinical onset. Such polymorphism is known to be associated with the reduction of secreted IL-10 which may support the concept of accelerated Th-1 T-cell reactivity. In conclusion, IL-10 promoter gene variants may contribute, but to a minor extent, to disease susceptibility in juvenile type 1 diabetes and should not be included in the routine genetic screening of high-risk individuals.

Adolescent↗

PubMed2006

Overexpression of synoviolin in peripheral blood and synoviocytes from rheumatoid arthritis patients and continued elevation in nonresponders to infliximab treatment.

OBJECTIVE: Synoviolin is a novel E3 ubiquitin ligase that has been implicated in the pathogenesis of rheumatoid arthritis (RA). The purpose of this study was to examine the expression and regulation of synoviolin by tumor necrosis factor alpha (TNFalpha), both in vivo and in vitro. METHODS: A total of 54 RA patients and 23 healthy control subjects were analyzed before, 4 hours after the first infusion, and at week 22 of infliximab treatment. Clinical response was assessed by the American College of Rheumatology criteria for 20% improvement and the Disease Activity Score in 28 joints (DAS28) at 6 months. Synoviolin messenger RNA expression was measured by real-time reverse transcription-polymerase chain reaction in peripheral blood (PB) and fibroblast-like synoviocytes (FLS) and with and without TNFalpha or interleukin-1beta (IL-1beta) stimulation. RESULTS: Synoviolin expression was increased in whole PB obtained from RA patients as compared with that from healthy controls and was significantly reduced early and late after infliximab treatment in responders, but in not nonresponders. Reduction in synoviolin expression was associated with reduced levels of markers of disease activity, including C-reactive protein levels. Nonresponders to infliximab therapy had significantly higher synoviolin expression at baseline as compared with responders, and this elevation persisted despite infliximab therapy. PB CD14+ monocytes expressed increased synoviolin levels compared with CD3+ lymphocytes, and TNFalpha or IL-1beta induced a further increase in expression in CD3+ cells. TNFalpha or IL-1beta induced sustained synoviolin expression in RA FLS. CONCLUSION: Elevated PB levels of synoviolin were identified in circulating PB mononuclear cells and were associated with nonresponse to infliximab treatment. Sustained up-regulation of synoviolin by IL-lbeta and TNFalpha may contribute to prolonged survival of immune cells and dysregulated FLS proliferation, leading to RA chronicity.

Antibodies, Monoclonal↗

PubMed2006

NASBA: a novel approach to assess hormonal receptors and ERBB2 status in breast cancer.

In human breast cancer, estrogen receptor-alpha (ERalpha), progesterone receptor (PR) and human epidermal growth factor receptor (ERBB2) status are currently determined using different techniques. We propose to assess the mRNA expression of these three clinically relevant markers using a unique technique, real-time nucleic acid sequence-based amplification (NASBA). Gene expression of hormone receptors was analyzed and compared to the cytosolic functional protein content as determined with a ligand binding assay (LBA), while ERBB2 mRNA expression was compared to quantitative PCR and ELISA. We observed that the three markers are significantly overexpressed at the mRNA level in positive tumors, as measured by DNA- or protein-based techniques. Biostatistical analysis of the receiver operating characteristic (ROC) curve demonstrated high concordance between NASBA and LBA [area under the curve (AUC) for ROC of 0.899] and showed that ERalpha status could be predicted using the molecular assay with a sensitivity of 72.7% and a specificity of 93.5%. Similar results were obtained for PR (AUC ROC 0.938, sensitivity 75.3%, specificity 100%). Moreover, excellent concordance was observed between NASBA, quantitative PCR and ELISA with respect to ERBB2 (AUC ROC 0.92, sensitivity 90%, specificity 89.7%; and AUC ROC 0.98, sensitivity 100%, specificity 91.5%, respectively). These results suggest that NASBA is well suited for assessing ER, PR and ERBB2 status in breast tumor samples. This approach is rapid, highly sensitive and a standardized method that could be complementary to the existing techniques, especially for small tumors.

Adult↗

PubMed2005

Longitudinal study of cytokine and immune transcription factor mRNA expression in septic shock.

Success in treating severe sepsis will require relevant tools to monitor the patient immunoinflammatory status. This study aimed to investigate the feasibility of measuring a panel of immunological mediator mRNAs in whole blood and to study their prognostic values in septic shock patients. At the onset of shock, compared to healthy volunteers, mRNA levels in septic shock patients were increased for IL-10, IL-1beta, and high mobility group B1 (HMGB1) and decreased for transforming growth factor beta 1, the Th1, and Th2 transcription factors, T-bet and GATA-3, respectively. Single parameter analysis highlighted an increased expression of IL-10 and HMGB1 mRNA in nonsurvivors and a significant rise over time of GATA3 in survivors. Combining the expression levels of four genes, hierarchical cluster analysis showed that up to 95% of the patients with a similar outcome displayed transcriptional similarities. These results illustrate both the potential of whole blood mRNA quantification assays and the interest of a multiparametric strategy to better stratify septic patients.

Aged↗

PubMed2005

Messenger RNA expression of major histocompatibility complex class II genes in whole blood from septic shock patients.

OBJECTIVE: The decreased expression of human leukocyte antigen (HLA)-DR on monocytes is proposed as a major feature of sepsis-induced immunodepression. The objective of the present study was to investigate, in whole blood from septic shock patients, the messenger RNA (mRNA) expression of a gene panel, which is essential to ensure major histocompatibility complex class II protein structure, transport, and peptide loading. DESIGN: The authors conducted a cohort study. SETTING: This study was conducted in intensive care units at a university hospital. SUBJECTS: The study included septic shock patients (n = 41) and healthy volunteers (n = 15). MEASUREMENTS AND MAIN RESULTS: Using quantitative reverse transcriptase-polymerase chain reaction, we found that the highly polymorphic HLA-DRB1 and nonpolymorphic-DRA mRNA levels were significantly decreased in whole blood from patients with septic shock compared with healthy volunteer both on days 1-3 and 4-10 after the onset of shock. This profile was also observed for genes encoding the invariant chain, the transcription factor class II transactivator (CIITA), and the enzymes involved in the peptide loading cathepsin S, HLA-DMA, and -DMB. The monocyte surface expression of HLA-DR measured by flow cytometry was significantly correlated with the whole-blood mRNA levels of HLA-DRB1 and -DRA and to a lesser extent with the other CIITA-regulated genes HLA-DMA and invariant chain. The correlation between HLA-DRB mRNA and cell-surface expression levels was also observed in a small subset of purified monocyte samples. Regarding the temporal relationship, a significant increase of whole-blood HLA-DRA, -DMA, -DMB, invariant chain, and CIITA mRNA level was observed in survivors (p = .001), whereas expressions remained low in nonsurvivors. CONCLUSIONS: A global transcriptional down regulation of a gene panel required for MHC II-restricted antigen presentation may occur in the course of septic shock. Our results suggest that the transcriptional resumption of CIITA-regulated genes might contribute to the recovery of membrane HLA-DR expression observed in survivors. These results obtained at the mRNA level support previous reports describing the loss of monocyte HLA-DR at the protein level and thus confirm the potential of measuring monocyte HLA-DR in septic patient followup.

Adult↗

PubMed2004

Genome-wide analysis of gene expression in neuroblastomas detected by mass screening.

Neuroblastoma (NB) is the most common extracranial solid tumor of childhood and the third most common pediatric cancer. Although numerous factors including patient age, disease stage and genetic abnormalities have been shown to be predictive of outcome, the mechanisms responsible for the highly variable clinical behavior of this tumor remain largely unknown. In order to gain new insights into the biology of this tumor, we performed microarray analysis and compared the gene expression patterns of NB detected by mass screening, characterized by highly probable spontaneous regression, versus stage 4 NB with poor prognosis. The bioinformatics analysis revealed a set of 19 discriminatory genes that may play a significant role in the natural progression of the disease. Validation of these results and further mechanistic studies would shed new light on the biology of tumor progression, and provide new tools to predict clinical outcome in children with NB.

Child, Preschool↗

PubMed2004

Peptidylpropyl isomerase B (PPIB): a suitable reference gene for mRNA quantification in peripheral whole blood.

Quantitative real-time RT-PCR is a very powerful technique for measuring gene expression at the mRNA level. In order to compare mRNA expression in different experimental or clinical conditions, expression of a target gene has to be normalized to an appropriate internal standard, which is generally a housekeeping gene. In our study, we have tested several housekeeping genes in peripheral whole blood of healthy volunteers and patients suffering from inflammatory diseases. A first analysis of 91 samples illustrated that the mRNA expression of peptidylpropyl isomerase B (PPIB) encoding for cyclophilin B protein, is more stable than beta actin and glyceraldehyde-3-phosphate dehydrogenase, which are both commonly selected as internal standard. Among the three genes tested, beta actin displayed the highest inter-sample variation of expression. The constancy of PPIB mRNA expression was further confirmed by 214 additional samples. In conclusion, we showed that PPIB, in contrast to beta actin and glyceraldehyde-3-phosphate dehydrogenase, is a suitable housekeeping gene in human peripheral blood.

Benchmarking↗

PubMed2004

Multiparametric duplex real-time nucleic acid sequence-based amplification assay for mRNA profiling.

Nucleic acid sequence-based amplification (NASBA) is a sensitive isothermal transcription-based amplification method. We have developed real-time NASBA assays to detect mRNA coding for the estrogen receptor alpha (ESR1) and the progesterone receptor (PGR) in breast tumors by means of duplex reactions using cyclophilin B (PPIB) as the normalizing gene. Both the ESR1/PPIB and PGR/PPIB duplex NASBA assays are highly sensitive, specific, and reproducible. Quantification is determined using external standard calibration curves and the ratio between the number of target and housekeeping gene mRNA copies. Amplification of the target gene in the duplex NASBA assay was disrupted when this latter was mixed with a large amount of the housekeeping PPIB gene, suggesting that it is preferable for the normalizing gene chosen to have an expression level comparable to the target gene. Sensitivity and robustness of the duplex NASBA assays were assessed in breast cancer cell lines. Such a rapid and easy-to-use multiparametric duplex real-time NASBA assay could also advantageously be set up for other mRNA profiling applications.

Biological Assay↗

PubMed2004

DNA nucleic acid sequence-based amplification-based genotyping for polymorphism analysis.

Nucleic acid sequence-based amplification (NASBA) is a sensitive isothermal transcription-based amplification method known to be a suitable tool for RNA research. We demonstrate that NASBA technology can be applied to single nucleotide polymorphism (SNP) analysis using human genomic DNA as a template. Combination of DNA NASBA with multiplex hybridization of specific molecular beacons makes it possible to unambiguously discriminate the presence of the SNP of interest. This protocol is easy-to-use, robust, and makes it possible to rapidly detect single nucleotide substitutions in clinical or cell line DNA sequences using a large range of DNA input. Such a real-time genotyping DNA NASBA assay can find broad application in clinical diagnostics.

Base Sequence↗