37 results on '"Bigot N"'
Search Results
2. P226 Disability in Crohn’s Disease Patients at diagnosis: Findings from the CROCO (Crohn´s Disease Cohort) study
- Author
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Revés, J, primary, Roager Madsen, G, additional, Burisch, J, additional, Wong, C, additional, Arebi, N, additional, Bonnet-Dodel, M, additional, Buisson, A, additional, Gatt, K, additional, Ellul, P, additional, Vieujean, S, additional, Ordas, I, additional, Duricova, D, additional, Rodríguez-Lago, I, additional, Sebastian, S, additional, Mocanu, I, additional, Kaimakliotis, I, additional, Goldis, A, additional, Hernandez, V, additional, Nachury, M, additional, Fumery, M, additional, Alloca, M, additional, Pedersen, N, additional, Barberio, B, additional, Guedes, A, additional, Ribeiro, R, additional, Ungaro, R, additional, Mary, J Y, additional, Bigot, N, additional, Lambert, J, additional, Colombel, J F, additional, and Torres, J, additional
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- 2024
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3. Simulation within simulation for agent decision-making: Theoretical foundations from cognitive science to operational computer model
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Buche, C., Le Bigot, N., and Polceanu, M.
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- 2016
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4. 4-Hexyl-1,3-phenylenediol, a nuclear factor-κB inhibitor, improves photodamaged skin and clinical signs of ageing in a double-blinded, randomized controlled trial
- Author
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Kaur, S., Kizoulis, M., Fantasia, J., Oddos, T., Bigot, N., Galera, P., Tucker-Samaras, S., Leyden, J. J., and Southall, M. D.
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- 2015
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5. ING3 is required for ATM signaling and DNA repair in response to DNA double strand breaks
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Mouche, A., primary, Archambeau, J., additional, Ricordel, C., additional, Chaillot, L., additional, Bigot, N., additional, Guillaudeux, T., additional, Grenon, M., additional, and Pedeux, R., additional
- Published
- 2019
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6. ING1b negatively regulates HIF1α protein levels in adipose-derived stromal cells by a SUMOylation-dependent mechanism
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Bigot, N, Guérillon, C, Loisel, S, Bertheuil, N, Sensebé, L, Tarte, K, Pedeux, R, Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES), Microenvironnement et cancer (MiCa), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Structure Fédérative de Recherche en Biologie et Santé de Rennes ( Biosit : Biologie - Santé - Innovation Technologique ), Etablissement Français du Sang Bretagne, EFS, Centre Hospitalier Universitaire [Rennes], Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, STROMALab, Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Vétérinaire de Toulouse (ENVT), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Etablissement Français du Sang-Institut National de la Santé et de la Recherche Médicale (INSERM), Etablissement Français du Sang Pyrénées Méditerranée, This work was supported by the ANR program (SAFE 2012) (ANR-11-RPIB-0012) whose recipients are NBi, SL, LS, KT and RP. NBi, SL, RP and KT are also supported with grants from the Université Rennes 1 (emerging scientific challenges 2013). CG is recipient of a doctoral fellowship from the French Ministry of Education and Research and from the FRM (Fondation pour la Recherche Médicale, FDT20130928015). KT and LS are also supported by ECELLFRANCE (ANR-11-INSB-005) and the European Center for Transplantation Sciences and Immunotherapy (IHU CESTI, ANR-10-IBHU-0005). RP is supported by AIS Rennes Métropole, INSERM (Institut National de la Santé et de la Recherche Médicale) and La Ligue Contre le Cancer (Grand Ouest)., ANR-11-RPIB-0012,SAFE,Production sécurisée de Cellules stromales du tissu adipeux pour la thérapie cellulaire(2011), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Ecole Nationale Vétérinaire de Toulouse (ENVT), Université Fédérale Toulouse Midi-Pyrénées-Institut National de la Santé et de la Recherche Médicale (INSERM)-Etablissement Français du Sang-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR), Université de Rennes (UR)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Structure Fédérative de Recherche en Biologie et Santé de Rennes ( Biosit : Biologie - Santé - Innovation Technologique ), Université de Toulouse (UT), Université de Toulouse (UT)-Université de Toulouse (UT)-Ecole Nationale Vétérinaire de Toulouse (ENVT), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National Polytechnique (Toulouse) (Toulouse INP), and Université de Toulouse (UT)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Etablissement Français du Sang-Centre National de la Recherche Scientifique (CNRS)
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Protein Stability ,[SDV]Life Sciences [q-bio] ,Tumor Suppressor Proteins ,Intracellular Signaling Peptides and Proteins ,Nuclear Proteins ,Sumoylation ,Hypoxia-Inducible Factor 1, alpha Subunit ,Models, Biological ,Protein Inhibitors of Activated STAT ,Cell Hypoxia ,Adipose Tissue ,Proteolysis ,Humans ,Cell Lineage ,Original Article ,Gene Silencing ,Stromal Cells ,Poly-ADP-Ribose Binding Proteins ,Cells, Cultured ,Inhibitor of Growth Protein 1 ,DNA Damage - Abstract
International audience; Hypoxic niches help maintain mesenchymal stromal cell properties, and their amplification under hypoxia sustains their immature state. However, how MSCs maintain their genomic integrity in this context remains elusive, since hypoxia may prevent proper DNA repair by downregulating expression of BRCA1 and RAD51. Here, we find that the ING1b tumor suppressor accumulates in adipose-derived stromal cells (ADSCs) upon genotoxic stress, owing to SUMOylation on K193 that is mediated by the E3 small ubiquitin-like modifier (SUMO) ligase protein inhibitor of activated STAT protein γ (PIAS4). We demonstrate that ING1b finely regulates the hypoxic response by triggering HIF1α proteasomal degradation. On the contrary, when mutated on its SUMOylation site, ING1b failed to efficiently decrease HIF1α levels. Consistently, we observed that the adipocyte differentiation, generally described to be downregulated by hypoxia, was highly dependent on ING1b expression, during the early days of this process. Accordingly, contrary to what was observed with HIF1α, the absence of ING1b impeded the adipogenic induction under hypoxic conditions. These data indicate that ING1b contributes to adipogenic induction in adipose-derived stromal cells, and thus hinders the phenotype maintenance of ADSCs.
- Published
- 2014
7. Studying the function of mitochondrial ING2, a tumor suppressor protein frequently lost in non-small cell lung cancer
- Author
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Ricordel, C., primary, Labalette-Tiercin, M., additional, Guerillon, C., additional, Bigot, N., additional, Mouche, A., additional, Burel, A., additional, Lena, H., additional, Guillaudeux, T., additional, and Pedeux, R., additional
- Published
- 2015
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8. ING1b negatively regulates HIF1α protein levels in adipose-derived stromal cells by a SUMOylation-dependent mechanism
- Author
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Bigot, N, primary, Guérillon, C, additional, Loisel, S, additional, Bertheuil, N, additional, Sensebé, L, additional, Tarte, K, additional, and Pedeux, R, additional
- Published
- 2015
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9. Involvement and alteration of the Sonic Hedgehog pathway is associated with decreased cholesterol level in trisomy 18 and SLO amniocytes
- Author
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Gruchy, N., primary, Bigot, N., additional, Jeanne Pasquier, C., additional, Read, M.H., additional, Odent, S., additional, Galera, P., additional, and Leporrier, N., additional
- Published
- 2014
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10. SNORC, a new specific marker of human differentiated articular chondrocytes
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Ollitrault, D., primary, Legendre, F., additional, Gomez-Leduc, T., additional, Bigot, N., additional, Leclercq, S., additional, Bauge, C., additional, Boumediene, K., additional, Demoor, M., additional, and Galera, P., additional
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- 2012
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11. 568 MODULATION OF CHONDROCYTE METABOLIC PATHWAYS BY NSAIDS AND THE CYCLOOXYGENASE-INHIBITING NITRIC OXIDE DONATOR (CINOD) NCX 429
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Maneix, L., primary, Ollitrault, D., additional, Bigot, N., additional, Duval, E., additional, Bolla, M., additional, Viappiani, S., additional, and Boumediene, K., additional
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- 2010
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12. Author Correction: PARP14 and PARP9/DTX3L regulate interferon-induced ADP-ribosylation.
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Kar P, Chatrin C, Đukić N, Suyari O, Schuller M, Zhu K, Prokhorova E, Bigot N, Baretić D, Ahel J, Elsborg JD, Nielsen ML, Clausen T, Huet S, Niepel M, Sanyal S, Ahel D, Smith R, and Ahel I
- Published
- 2024
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13. French early nationwide idecabtagene vicleucel chimeric antigen receptor T-cell therapy experience in patients with relapsed/refractory multiple myeloma (FENIX): A real-world IFM study from the DESCAR-T registry.
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Ferment B, Lambert J, Caillot D, Lafon I, Karlin L, Lazareth A, Touzeau C, Leleu X, Moya N, Harel S, Perrot A, Bories P, Vincent L, Lamure S, Mohty M, Malard F, Manier S, Yakoub-Agha I, Schiano De Colella JM, Brisou G, Talbot A, Decaux O, Houot R, Le Gouill S, Bigot N, Facon T, Corre J, Moreau P, and Arnulf B
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- Humans, Male, Female, Middle Aged, Aged, France, Adult, B-Cell Maturation Antigen immunology, Aged, 80 and over, Receptors, Chimeric Antigen therapeutic use, Multiple Myeloma therapy, Registries, Immunotherapy, Adoptive adverse effects, Immunotherapy, Adoptive methods
- Abstract
Idecabtagene vicleucel (ide-cel), a chimeric antigen receptor T-cell therapy targeting B-cell maturation antigen (BCMA), received early access program (EAP) authorization in France in April 2021 for relapsed/refractory multiple myeloma (RRMM). We conducted a real-world registry-based multicentre observational study in 11 French hospitals to evaluate ide-cel outcomes. Data from 176 RRMM patients who underwent apheresis between June 2021 and November 2022 were collected from the French national DESCAR-T registry. Of these, 159 patients (90%) received ide-cel. Cytokine release syndrome occurred in 90% with 2% grade ≥3, and neurotoxicity occurred in 12% with 3% grade ≥3. Over the first 6 months, the best overall response and ≥complete response rates were 88% and 47% respectively. The median progression-free survival (PFS) from the ide-cel infusion was 12.5 months, the median overall survival (OS) was 20.8 months and the estimated OS rate at 12 months was 73.3%. Patients with extra-medullary disease (EMD) had impaired PFS (6.2 months vs. 14.8 months). On multivariable analysis, EMD and previous exposure to BCMA-targeted immunoconjugate or T-cell-redirecting GPRC5D bispecific antibody were associated with inferior PFS. Our study supports ide-cel's feasibility, safety and efficacy in real-life settings, emphasizing the importance of screening for EMD and considering prior treatments to optimize patient selection., (© 2024 The Authors. British Journal of Haematology published by British Society for Haematology and John Wiley & Sons Ltd.)
- Published
- 2024
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14. Isatuximab, lenalidomide, dexamethasone and bortezomib in transplant-ineligible multiple myeloma: the randomized phase 3 BENEFIT trial.
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Leleu X, Hulin C, Lambert J, Bobin A, Perrot A, Karlin L, Roussel M, Montes L, Cherel B, Chalopin T, Slama B, Chretien ML, Laribi K, Dingremont C, Roul C, Mariette C, Rigaudeau S, Calmettes C, Dib M, Tiab M, Vincent L, Delaunay J, Santagostino A, Macro M, Bourgeois E, Orsini-Piocelle F, Gay J, Bareau B, Bigot N, Vergez F, Lebreton P, Tabrizi R, Waultier-Rascalou A, Frenzel L, Le Calloch R, Chalayer E, Braun T, Lachenal F, Corm S, Kennel C, Belkhir R, Bladé JS, Joly B, Richez-Olivier V, Gardeney H, Demarquette H, Robu-Cretu D, Garderet L, Newinger-Porte M, Kasmi A, Royer B, Decaux O, Arnulf B, Belhadj K, Touzeau C, Mohty M, Manier S, Moreau P, Avet-Loiseau H, Corre J, and Facon T
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- Humans, Aged, Male, Female, Antibodies, Monoclonal, Humanized administration & dosage, Antibodies, Monoclonal, Humanized therapeutic use, Antibodies, Monoclonal, Humanized adverse effects, Neoplasm, Residual, Treatment Outcome, Multiple Myeloma drug therapy, Multiple Myeloma pathology, Bortezomib administration & dosage, Bortezomib therapeutic use, Lenalidomide administration & dosage, Lenalidomide therapeutic use, Dexamethasone administration & dosage, Dexamethasone therapeutic use, Antineoplastic Combined Chemotherapy Protocols therapeutic use
- Abstract
CD38-targeting immunotherapy is approved in combination with lenalidomide and dexamethasone in patients with newly diagnosed multiple myeloma (NDMM) that are transplant ineligible (TI) and is considered the best standard of care (SOC). To improve current SOC, we evaluated the added value of weekly bortezomib (V) to isatuximab plus lenalidomide and dexamethasone (IsaRd versus Isa-VRd). This Intergroupe Francophone of Myeloma phase 3 study randomized 270 patients with NDMM that were TI, aged 65-79 years, to IsaRd versus Isa-VRd arms. The primary endpoint was a minimal residual disease (MRD) negativity rate at 10
-5 by next-generation sequencing at 18 months from randomization. Key secondary endpoints included response rates, MRD assessment rates, survival and safety. The 18-month MRD negativity rates at 10-5 were reported in 35 patients (26%, 95% confidence interval (CI) 19-34) in IsaRd versus 71 (53%, 95% CI 44-61) in Isa-VRd (odds ratio for MRD negativity 3.16, 95% CI 1.89-5.28, P < 0.0001). The MRD benefit was consistent across subgroups at 10-5 and 10-6 , and was already observed at month 12. The proportion of patients with complete response or better at 18 months was higher with Isa-VRd (58% versus 33%; P < 0.0001), as was the proportion of MRD negativity and complete response or better (37% versus 17%; P = 0.0003). At a median follow-up of 23.5 months, no difference was observed for survival times (immature data). The addition of weekly bortezomib did not significantly affect the relative dose intensity of IsaRd. Isa-VRd significantly increased MRD endpoints, including the 18-month negativity rate at 10-5 , the primary endpoint, compared with IsaRd. This study proposes Isa-VRd as a new SOC for patients with NDMM that are TI. ClinicalTrials.gov identifier: NCT04751877 ., (© 2024. The Author(s).)- Published
- 2024
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15. Dynamic BTB-domain filaments promote clustering of ZBTB proteins.
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Mance L, Bigot N, Zhamungui Sánchez E, Coste F, Martín-González N, Zentout S, Biliškov M, Pukało Z, Mishra A, Chapuis C, Arteni AA, Lateur A, Goffinont S, Gaudon V, Talhaoui I, Casuso I, Beaufour M, Garnier N, Artzner F, Cadene M, Huet S, Castaing B, and Suskiewicz MJ
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- Animals, Humans, Cell Nucleus metabolism, Cell Nucleus genetics, Crystallography, X-Ray, HEK293 Cells, Models, Molecular, Protein Binding, Protein Multimerization, Repressor Proteins metabolism, Repressor Proteins genetics, Repressor Proteins chemistry, Xenopus laevis, BTB-POZ Domain, Transcription Factors metabolism, Transcription Factors genetics, Xenopus Proteins genetics, Xenopus Proteins metabolism, Xenopus Proteins chemistry
- Abstract
The formation of dynamic protein filaments contributes to various biological functions by clustering individual molecules together and enhancing their binding to ligands. We report such a propensity for the BTB domains of certain proteins from the ZBTB family, a large eukaryotic transcription factor family implicated in differentiation and cancer. Working with Xenopus laevis and human proteins, we solved the crystal structures of filaments formed by dimers of the BTB domains of ZBTB8A and ZBTB18 and demonstrated concentration-dependent higher-order assemblies of these dimers in solution. In cells, the BTB-domain filamentation supports clustering of full-length human ZBTB8A and ZBTB18 into dynamic nuclear foci and contributes to the ZBTB18-mediated repression of a reporter gene. The BTB domains of up to 21 human ZBTB family members and two related proteins, NACC1 and NACC2, are predicted to behave in a similar manner. Our results suggest that filamentation is a more common feature of transcription factors than is currently appreciated., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 Elsevier Inc. All rights reserved.)
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- 2024
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16. PARP14 and PARP9/DTX3L regulate interferon-induced ADP-ribosylation.
- Author
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Kar P, Chatrin C, Đukić N, Suyari O, Schuller M, Zhu K, Prokhorova E, Bigot N, Baretić D, Ahel J, Elsborg JD, Nielsen ML, Clausen T, Huet S, Niepel M, Sanyal S, Ahel D, Smith R, and Ahel I
- Subjects
- Humans, Ubiquitination, HEK293 Cells, SARS-CoV-2 metabolism, Signal Transduction, COVID-19 virology, COVID-19 metabolism, Neoplasm Proteins, ADP-Ribosylation, Poly(ADP-ribose) Polymerases metabolism, Poly(ADP-ribose) Polymerases genetics, Ubiquitin-Protein Ligases metabolism, Ubiquitin-Protein Ligases genetics, Interferons metabolism
- Abstract
PARP-catalysed ADP-ribosylation (ADPr) is important in regulating various cellular pathways. Until recently, PARP-dependent mono-ADP-ribosylation has been poorly understood due to the lack of sensitive detection methods. Here, we utilised an improved antibody to detect mono-ADP-ribosylation. We visualised endogenous interferon (IFN)-induced ADP-ribosylation and show that PARP14 is a major enzyme responsible for this modification. Fittingly, this signalling is reversed by the macrodomain from SARS-CoV-2 (Mac1), providing a possible mechanism by which Mac1 counteracts the activity of antiviral PARPs. Our data also elucidate a major role of PARP9 and its binding partner, the E3 ubiquitin ligase DTX3L, in regulating PARP14 activity through protein-protein interactions and by the hydrolytic activity of PARP9 macrodomain 1. Finally, we also present the first visualisation of ADPr-dependent ubiquitylation in the IFN response. These approaches should further advance our understanding of IFN-induced ADPr and ubiquitin signalling processes and could shed light on how different pathogens avoid such defence pathways., (© 2024. The Author(s).)
- Published
- 2024
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17. Low non-relapse mortality and good haematological and renal responses after autologous haematopoietic stem cell transplantation in multiple myeloma patients with renal insufficiency at transplant: A prospective Société Francophone de Greffe de Moelle-Thérapie Cellulaire observational study.
- Author
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Garderet L, Ouldjeriouat H, Bekadja MA, Daguenet E, Bigot N, Vincent L, Roos-Weil D, Vignon M, Ikhlef S, Abraham J, Escoffre-Barbe M, Lioure B, Nacer RA, Lafon I, Mariette C, Karlin L, Morel P, Gilis L, Le Ray E, Blouet A, Nguyen Quoc S, Boffa JJ, Ronco P, Lambert J, and Cornillon J
- Subjects
- Humans, Transplantation, Autologous, Melphalan, Treatment Outcome, Prospective Studies, Neoplasm Recurrence, Local drug therapy, Transplantation Conditioning, Retrospective Studies, Multiple Myeloma drug therapy, Hematopoietic Stem Cell Transplantation adverse effects, Renal Insufficiency etiology, Renal Insufficiency therapy
- Abstract
High-dose melphalan followed by autologous haematopoietic stem cell transplantation is widely used in newly diagnosed multiple myeloma (MM) patients as upfront therapy. However, the safety and efficacy of transplantation in patients with renal insufficiency (RI) are controversial. We followed a multicentre (16 SFGM-TC centres) prospective cohort of 50 newly diagnosed MM patients with a serum creatinine clearance of <40 mL/min at transplantation. Patients received a recommended dose of melphalan of 140 mg/m
2 . The primary end-point was the non-relapse mortality at Day 100. One death occurred during the first 100 days post-transplant. The median time to neutrophil engraftment was 12 days and to platelet engraftment was 13 days. The haematological response improved in 69% of patients, with best responses from partial response (PR) to very good partial response (VGPR) (10%), from PR to complete response (CR)/stringent complete response (sCR) (16%), from VGPR to CR/sCR (39%) and from CR to sCR (2%). At 2 years, the overall survival was 84%, the progression-free survival was 70% and the cumulative incidence of relapse was 20%. The renal response improved in 59% of patients, with the best renal responses post-transplant being minimal (9%), partial (2%) and complete (48%). Autologous transplantation was safe and effective in myeloma patients with RI at transplant., (© 2023 The Authors. British Journal of Haematology published by British Society for Haematology and John Wiley & Sons Ltd.)- Published
- 2024
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18. The recruitment of ACF1 and SMARCA5 to DNA lesions relies on ADP-ribosylation dependent chromatin unfolding.
- Author
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Pinto Jurado E, Smith R, Bigot N, Chapuis C, Timinszky G, and Huet S
- Subjects
- DNA metabolism, Adenosine Triphosphatases metabolism, DNA Repair, ADP-Ribosylation, Chromatin, DNA Damage
- Abstract
ADP-ribosylation signaling orchestrates the recruitment of various repair actors and chromatin remodeling processes promoting access to lesions during the early stages of the DNA damage response. The chromatin remodeler complex ACF, composed of the ATPase subunit SMARCA5/SNF2H and the cofactor ACF1/BAZ1A, is among the factors that accumulate at DNA lesions in an ADP-ribosylation dependent manner. In this work, we show that each subunit of the ACF complex accumulates to DNA breaks independently from its partner. Furthermore, we demonstrate that the recruitment of SMARCA5 and ACF1 to sites of damage is not due to direct binding to the ADP-ribose moieties but due to facilitated DNA binding at relaxed ADP-ribosylated chromatin. Therefore, our work provides new insights regarding the mechanisms underlying the timely accumulation of ACF1 and SMARCA5 to DNA lesions, where they contribute to efficient DNA damage resolution.
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- 2024
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19. HPF1-dependent histone ADP-ribosylation triggers chromatin relaxation to promote the recruitment of repair factors at sites of DNA damage.
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Smith R, Zentout S, Rother M, Bigot N, Chapuis C, Mihuț A, Zobel FF, Ahel I, van Attikum H, Timinszky G, and Huet S
- Subjects
- Poly(ADP-ribose) Polymerases chemistry, Poly (ADP-Ribose) Polymerase-1 genetics, ADP-Ribosylation, DNA Damage, DNA Repair, DNA metabolism, Histones metabolism, Chromatin
- Abstract
Poly(ADP-ribose) polymerase 1 (PARP1) activity is regulated by its co-factor histone poly(ADP-ribosylation) factor 1 (HPF1). The complex formed by HPF1 and PARP1 catalyzes ADP-ribosylation of serine residues of proteins near DNA breaks, mainly PARP1 and histones. However, the effect of HPF1 on DNA repair regulated by PARP1 remains unclear. Here, we show that HPF1 controls prolonged histone ADP-ribosylation in the vicinity of the DNA breaks by regulating both the number and length of ADP-ribose chains. Furthermore, we demonstrate that HPF1-dependent histone ADP-ribosylation triggers the rapid unfolding of chromatin, facilitating access to DNA at sites of damage. This process promotes the assembly of both the homologous recombination and non-homologous end joining repair machineries. Altogether, our data highlight the key roles played by the PARP1/HPF1 complex in regulating ADP-ribosylation signaling as well as the conformation of damaged chromatin at early stages of the DNA damage response., (© 2023. The Author(s), under exclusive licence to Springer Nature America, Inc.)
- Published
- 2023
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20. Augmented reality on industrial assembly line: Impact on effectiveness and mental workload.
- Author
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Drouot M, Le Bigot N, Bricard E, Bougrenet JL, and Nourrit V
- Subjects
- Humans, Task Performance and Analysis, Workload, Augmented Reality
- Abstract
Studies examining the potential of augmented reality (AR) to improve assembly tasks are often unrepresentative of real assembly line conditions and assess mental workload only through subjective measurements and leads to conflicting results. We proposed a study directly carried out in industrial settings, to compare the impact of AR-based instructions to computerized instructions, on assembly effectiveness (completion time and errors) and mental workload using objective (eye tracking), subjective (NASA-TLX) and behavioral measurements (dual task paradigm). According to our results, AR did not improve effectiveness (increased assembly times and no decrease in assembly errors). Two out of three measurements indicated that AR led to more mental workload for simple assembly workstation, but equated computer instructions for complex workstation. Our data also suggest that, AR users were less able to detect external events (danger, alert), which may play an important role in the occurrence of work accidents., (Copyright © 2022 Elsevier Ltd. All rights reserved.)
- Published
- 2022
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21. ING3 is required for ATM signaling and DNA repair in response to DNA double strand breaks.
- Author
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Mouche A, Archambeau J, Ricordel C, Chaillot L, Bigot N, Guillaudeux T, Grenon M, and Pedeux R
- Subjects
- A549 Cells, Acetyltransferases genetics, Animals, Antibiotics, Antineoplastic pharmacology, BRCA1 Protein metabolism, Cell Line, Tumor, DNA genetics, DNA metabolism, DNA Breaks, Double-Stranded, DNA-Binding Proteins metabolism, Doxorubicin pharmacology, Enzyme Activation genetics, Homeodomain Proteins genetics, Humans, Immunoglobulin Class Switching genetics, Lysine Acetyltransferase 5 genetics, Mice, RNA Interference, RNA, Small Interfering genetics, Saccharomyces cerevisiae genetics, Saccharomyces cerevisiae Proteins genetics, Signal Transduction genetics, Tumor Suppressor Proteins metabolism, Tumor Suppressor p53-Binding Protein 1 metabolism, Ubiquitin-Protein Ligases metabolism, Ataxia Telangiectasia Mutated Proteins metabolism, DNA End-Joining Repair genetics, Genomic Instability genetics, Homeodomain Proteins metabolism, Tumor Suppressor Proteins genetics
- Abstract
Inhibitor of Growth 3 (ING3) is a candidate tumor suppressor gene whose expression is lost in tumors such as hepatocellular carcinoma, head and neck squamous cell carcinoma and melanoma. In the present study, we show that ING3-depleted human cells and yeast cells deleted for its ortholog YNG2 are sensitive to DNA damage suggesting a conserved role in response to such stress. In human cells, ING3 is recruited to DNA double strand breaks and is required for ATM activation. Remarkably, in response to doxorubicin, ATM activation is dependent on ING3 but not on TIP60, whose recruitment to DNA breaks also depends on ING3. These events lead to ATM-mediated phosphorylation of NBS1 and the subsequent recruitment of RNF8, RNF168, 53BP1, and BRCA1, which are major mediators of the DNA damage response. Accordingly, upon genotoxic stress, DNA repair by non-homologous end joining (NHEJ) or homologous recombination (HR) were impaired in absence of ING3. Finally, immunoglobulin class switch recombination (CSR), a physiological mechanism requiring NHEJ repair, was impaired in the absence of ING3. Since deregulation of DNA double strand break repair is associated with genomic instability, we propose a novel function of ING3 as a caretaker tumor suppressor involved in the DNA damage signaling and repair.
- Published
- 2019
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22. Phosphorylation-mediated interactions with TOPBP1 couple 53BP1 and 9-1-1 to control the G1 DNA damage checkpoint.
- Author
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Bigot N, Day M, Baldock RA, Watts FZ, Oliver AW, and Pearl LH
- Subjects
- Ataxia Telangiectasia Mutated Proteins chemistry, Ataxia Telangiectasia Mutated Proteins genetics, Carrier Proteins genetics, Cell Cycle Checkpoints genetics, Checkpoint Kinase 1 chemistry, Checkpoint Kinase 1 genetics, DNA Replication genetics, DNA-Binding Proteins genetics, HeLa Cells, Humans, Methylation, Multiprotein Complexes genetics, Nuclear Proteins genetics, Phosphorylation, Protein Binding genetics, Protein Conformation, Protein Domains genetics, Protein Processing, Post-Translational genetics, S Phase genetics, Tumor Suppressor p53-Binding Protein 1 genetics, Ubiquitination genetics, Carrier Proteins chemistry, DNA Damage genetics, DNA-Binding Proteins chemistry, Multiprotein Complexes chemistry, Nuclear Proteins chemistry, Tumor Suppressor p53-Binding Protein 1 chemistry
- Abstract
Coordination of the cellular response to DNA damage is organised by multi-domain 'scaffold' proteins, including 53BP1 and TOPBP1, which recognise post-translational modifications such as phosphorylation, methylation and ubiquitylation on other proteins, and are themselves carriers of such regulatory signals. Here we show that the DNA damage checkpoint regulating S-phase entry is controlled by a phosphorylation-dependent interaction of 53BP1 and TOPBP1. BRCT domains of TOPBP1 selectively bind conserved phosphorylation sites in the N-terminus of 53BP1. Mutation of these sites does not affect formation of 53BP1 or ATM foci following DNA damage, but abolishes recruitment of TOPBP1, ATR and CHK1 to 53BP1 damage foci, abrogating cell cycle arrest and permitting progression into S-phase. TOPBP1 interaction with 53BP1 is structurally complimentary to its interaction with RAD9-RAD1-HUS1, allowing these damage recognition factors to bind simultaneously to the same TOPBP1 molecule and cooperate in ATR activation in the G1 DNA damage checkpoint., Competing Interests: NB, MD, RB, FW, AO, LP No competing interests declared, (© 2019, Bigot et al.)
- Published
- 2019
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23. Exogenous and endogenous shifts of attention in perihand space.
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Le Bigot N and Grosjean M
- Subjects
- Discrimination, Psychological, Female, Functional Laterality physiology, Humans, Male, Reaction Time physiology, Task Performance and Analysis, Young Adult, Attention physiology, Cues, Orientation, Spatial physiology, Space Perception physiology
- Abstract
While some studies have found that attentional orienting is altered in perihand space, most have not. One reason for such discrepancies may be related to the types of cues (uninformative and informative) that have been used, as they are known to induce different types of shifts of attention (exogenous and endogenous, respectively). To systematically address this question, two experiments were performed in which an uninformative peripheral cue (Experiment 1) or an informative central cue (Experiment 2) preceded a peripheral target with a short (100-150 ms) stimulus-onset asynchrony. Participants performed the task with their left hand, right hand, both hands, or no hands near the display. Cueing effects were obtained in both experiments, but they were only modulated by hand position in Experiment 1, with larger effects observed in the right- and both-hand conditions. These findings suggest that exogenous attention shifts are affected by hand proximity, while endogenous shifts are not.
- Published
- 2016
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24. Reply: Standardized procedure for bone marrow MSCs preparation for clinical use.
- Author
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Bigot N, Sensebé L, Tarte K, and Pedeux R
- Subjects
- Bone Marrow Cells, Humans, Hypoxia, Bone Marrow, Mesenchymal Stem Cells
- Published
- 2016
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25. Reduced NF-κB activity is observed in dermal fibroblasts from black-skinned African individuals.
- Author
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Bigot N, Gomez-Leduc T, Hervieu M, Gallienne F, Oddos T, Legendre F, Demoor M, and Galéra P
- Subjects
- Adult, Female, Humans, Middle Aged, Black People statistics & numerical data, Fibroblasts metabolism, NF-kappa B metabolism, Skin metabolism, White People statistics & numerical data
- Published
- 2016
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26. Hypoxia Differentially Modulates the Genomic Stability of Clinical-Grade ADSCs and BM-MSCs in Long-Term Culture.
- Author
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Bigot N, Mouche A, Preti M, Loisel S, Renoud ML, Le Guével R, Sensebé L, Tarte K, and Pedeux R
- Subjects
- Adipose Tissue pathology, Adult, Cell Culture Techniques, Cell Hypoxia, Female, Humans, Mesenchymal Stem Cells pathology, Time Factors, Adipose Tissue metabolism, DNA Damage, Genomic Instability, Mesenchymal Stem Cells metabolism, Recombinational DNA Repair
- Abstract
Long-term cultures under hypoxic conditions have been demonstrated to maintain the phenotype of mesenchymal stromal/stem cells (MSCs) and to prevent the emergence of senescence. According to several studies, hypoxia has frequently been reported to drive genomic instability in cancer cells and in MSCs by hindering the DNA damage response and DNA repair. Thus, we evaluated the occurrence of DNA damage and repair events during the ex vivo expansion of clinical-grade adipose-derived stromal cells (ADSCs) and bone marrow (BM)-derived MSCs cultured with platelet lysate under 21% (normoxia) or 1% (hypoxia) O2 conditions. Hypoxia did not impair cell survival after DNA damage, regardless of MSC origin. However, ADSCs, unlike BM-MSCs, displayed altered γH2AX signaling and increased ubiquitylated γH2AX levels under hypoxic conditions, indicating an impaired resolution of DNA damage-induced foci. Moreover, hypoxia specifically promoted BM-MSC DNA integrity, with increased Ku80, TP53BP1, BRCA1, and RAD51 expression levels and more efficient nonhomologous end joining and homologous recombination repair. We further observed that hypoxia favored mtDNA stability and maintenance of differentiation potential after genotoxic stress. We conclude that long-term cultures under 1% O2 were more suitable for BM-MSCs as suggested by improved genomic stability compared with ADSCs., (© AlphaMed Press.)
- Published
- 2015
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27. Up-regulation of type II collagen gene by 17β-estradiol in articular chondrocytes involves Sp1/3, Sox-9, and estrogen receptor α.
- Author
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Maneix L, Servent A, Porée B, Ollitrault D, Branly T, Bigot N, Boujrad N, Flouriot G, Demoor M, Boumediene K, Moslemi S, and Galéra P
- Subjects
- Animals, Binding Sites, Cartilage, Articular cytology, Cell Differentiation, Collagen Type II genetics, Humans, Male, Phenotype, Promoter Regions, Genetic, RNA, Small Interfering metabolism, Rabbits, Transcriptional Activation, Up-Regulation, Chondrocytes cytology, Collagen Type II metabolism, Estradiol pharmacology, Estrogen Receptor alpha metabolism, SOX9 Transcription Factor metabolism, Sp1 Transcription Factor metabolism, Sp3 Transcription Factor metabolism
- Abstract
Unlabelled: The existence of a link between estrogen deprivation and osteoarthritis (OA) in postmenopausal women suggests that 17β-estradiol (17β-E2) may be a modulator of cartilage homeostasis. Here, we demonstrate that 17β-E2 stimulates, via its receptor human estrogen receptor α 66 (hERα66), type II collagen expression in differentiated and dedifferentiated (reflecting the OA phenotype) articular chondrocytes. Transactivation of type II collagen gene (COL2A1) by ligand-independent transactivation domain (AF-1) of hERα66 was mediated by "GC" binding sites of the -266/-63-bp promoter, through physical interactions between ERα, Sp1/Sp3, Sox9, and p300, as demonstrated in chromatin immunoprecipitation (ChIP) and Re-Chromatin Immuno-Precipitation (Re-ChIP) assays in primary and dedifferentiated cells. 17β-E2 and hERα66 increased the DNA-binding activities of Sp1/Sp3 and Sox-9 to both COL2A1 promoter and enhancer regions. Besides, Sp1, Sp3, and Sox-9 small interfering RNAs (siRNAs) prevented hERα66-induced transactivation of COL2A1, suggesting that these factors and their respective cis-regions are required for hERα66-mediated COL2A1 up-regulation. Our results highlight the genomic pathway by which 17β-E2 and hERα66 modulate Sp1/Sp3 heteromer binding activity and simultaneously participate in the recruitment of the essential factors Sox-9 and p300 involved respectively in the chondrocyte-differentiated status and COL2A1 transcriptional activation. These novel findings could therefore be attractive for tissue engineering of cartilage in OA, by the fact that 17β-E2 could promote chondrocyte redifferentiation., Key Messages: 17β-E2 up-regulates type II collagen gene expression in articular chondrocytes. An ERα66/Sp1/Sp3/Sox-9/p300 protein complex mediates this stimulatory effect. This heteromeric complex interacts and binds to Col2a1 promoter and enhancer in vivo. Our findings highlight a new regulatory mechanism for 17β-E2 action in chondrocytes. 17β-E2 might be an attractive candidate for cartilage engineering applications.
- Published
- 2014
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28. SUMOylation of the ING1b tumor suppressor regulates gene transcription.
- Author
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Satpathy S, Guérillon C, Kim TS, Bigot N, Thakur S, Bonni S, Riabowol K, and Pedeux R
- Subjects
- Amino Acid Motifs, Cytokines genetics, Gene Expression Regulation, Genes, Tumor Suppressor, HEK293 Cells, Humans, Lysine metabolism, Poly-ADP-Ribose Binding Proteins, Promoter Regions, Genetic, Protein Inhibitors of Activated STAT metabolism, RNA-Binding Proteins metabolism, Ubiquitin-Conjugating Enzymes metabolism, Ubiquitins genetics, Homeodomain Proteins genetics, Homeodomain Proteins metabolism, Receptors, Cytoplasmic and Nuclear genetics, Receptors, Cytoplasmic and Nuclear metabolism, Sumoylation, Tumor Suppressor Proteins genetics, Tumor Suppressor Proteins metabolism
- Abstract
The INhibitor of Growth (ING) proteins are encoded as multiple isoforms in five ING genes (ING1 -5) and act as type II tumor suppressors. They are growth inhibitory when overexpressed and are frequently mislocalized or downregulated in several forms of cancer. ING1 and ING2 are stoichiometric members of histone deacetylase complexes, whereas ING3-5 are stoichiometric components of different histone acetyltransferase complexes. The INGs target these complexes to histone marks, thus acting as epigenetic regulators. ING proteins affect angiogenesis, apoptosis, DNA repair, metastasis and senescence, but how the proteins themselves are regulated is not yet clear. Here, we find a small ubiquitin-like modification (SUMOylation) of the ING1b protein and identify lysine 193 (K193) as the preferred ING1b SUMO acceptor site. We also show that PIAS4 is the E3 SUMO ligase responsible for ING1b SUMOylation on K193. Sequence alignment reveals that the SUMO consensus site on ING1b contains a phosphorylation-dependent SUMOylation motif (PDSM) and our data indicate that the SUMOylation on K193 is enhanced by the S199D phosphomimic mutant. Using an ING1b protein mutated at the major SUMOylation site (ING1b E195A), we further demonstrate that ING1b SUMOylation regulates the binding of ING1b to the ISG15 and DGCR8 promoters, consequently regulating ISG15 and DGCR8 transcription. These results suggest a role for ING1b SUMOylation in the regulation of gene transcription., (© The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)
- Published
- 2014
- Full Text
- View/download PDF
29. Shell extracts from the marine bivalve Pecten maximus regulate the synthesis of extracellular matrix in primary cultured human skin fibroblasts.
- Author
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Latire T, Legendre F, Bigot N, Carduner L, Kellouche S, Bouyoucef M, Carreiras F, Marin F, Lebel JM, Galéra P, and Serpentini A
- Subjects
- Animals, Fibroblasts drug effects, Humans, Primary Cell Culture, Skin drug effects, Tissue Extracts chemistry, Animal Shells chemistry, Extracellular Matrix drug effects, Pecten chemistry, Tissue Extracts pharmacology
- Abstract
Mollusc shells are composed of more than 95% calcium carbonate and less than 5% of an organic matrix consisting mostly of proteins, glycoproteins and polysaccharides. Previous studies have elucidated the biological activities of the shell matrices from bivalve molluscs on skin, especially on the expression of the extracellular matrix components of fibroblasts. In this work, we have investigated the potential biological activities of shell matrix components extracted from the shell of the scallop Pecten maximus on human fibroblasts in primary culture. Firstly, we demonstrated that shell matrix components had different effects on general cellular activities. Secondly, we have shown that the shell matrix components stimulate the synthesis of type I and III collagens, as well as that of sulphated GAGs. The increased expression of type I collagen is likely mediated by the recruitment of transactivating factors (Sp1, Sp3 and human c-Krox) in the -112/-61 bp COL1A1 promoter region. Finally, contrarily to what was obtained in previous works, we demonstrated that the scallop shell extracts have only a small effect on cell migration during in vitro wound tests and have no effect on cell proliferation. Thus, our research emphasizes the potential use of shell matrix of Pecten maximus for dermo-cosmetic applications.
- Published
- 2014
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30. The ING tumor suppressor genes: status in human tumors.
- Author
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Guérillon C, Bigot N, and Pedeux R
- Subjects
- Animals, Humans, Inhibitor of Growth Protein 1, Intracellular Signaling Peptides and Proteins metabolism, Nuclear Proteins metabolism, Tumor Suppressor Proteins metabolism, Genes, Tumor Suppressor, Intracellular Signaling Peptides and Proteins genetics, MicroRNAs genetics, Neoplasms genetics, Nuclear Proteins genetics, Tumor Suppressor Proteins genetics
- Abstract
ING genes (ING1-5) were identified has tumor suppressor genes. ING proteins are characterized as Type II TSGs since they are involved in the control of cell proliferation, apoptosis and senescence. They may also function as Type I TSGs since they are also involved in DNA replication and repair. Most studies have reported that they are frequently lost in human tumors and epigenetic mechanisms or misregulation of their transcription may be involved. Recently, studies have described that this loss may be caused by microRNA inhibition. Here, we summarize the current knowledge on ING functions, their involvement in tumor suppression and, in order to give a full assessment of the current knowledge, we review all the studies that have examined ING status in human cancers., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)
- Published
- 2014
- Full Text
- View/download PDF
31. NF-κB accumulation associated with COL1A1 transactivators defects during chronological aging represses type I collagen expression through a -112/-61-bp region of the COL1A1 promoter in human skin fibroblasts.
- Author
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Bigot N, Beauchef G, Hervieu M, Oddos T, Demoor M, Boumediene K, and Galéra P
- Subjects
- Adolescent, Adult, Aged, CCAAT-Binding Factor metabolism, Cells, Cultured, Cellular Senescence, Collagen Type I, alpha 1 Chain, Extracellular Matrix metabolism, Female, Fibroblasts cytology, Humans, Middle Aged, Phenotype, Skin cytology, Sp1 Transcription Factor metabolism, Sp3 Transcription Factor metabolism, Young Adult, Aging metabolism, Collagen Type I metabolism, Fibroblasts metabolism, NF-kappa B metabolism, Promoter Regions, Genetic physiology, Skin metabolism, Trans-Activators metabolism
- Abstract
The aging process, especially of the skin, is governed by changes in the epidermal, dermo-epidermal, and dermal compartments. Type I collagen, which is the major component of dermis extracellular matrix (ECM), constitutes a prime target for intrinsic and extrinsic aging-related alterations. In addition, under the aging process, pro-inflammatory signals are involved and collagens are fragmented owing to enhanced matrix metalloproteinase activities, and fibroblasts are no longer able to properly synthesize collagen fibrils. Here, we demonstrated that low levels of type I collagen detected in aged skin fibroblasts are attributable to an inhibition of COL1A1 transcription. Indeed, on one hand, we observed decreased binding activities of specific proteins 1 and 3, CCAAT-binding factor, and human collagen-Krüppel box, which are well-known COL1A1 transactivators acting through the -112/-61-bp promoter sequence. On the other hand, the aging process was accompanied by elevated amounts and binding activities of NF-κB (p65 and p50 subunits), together with an increased number of senescent cells. The forced expression of NF-κB performed in young fibroblasts was able to establish an old-like phenotype by repressing COL1A1 expression through the short -112/-61-bp COL1A1 promoter and by elevating the senescent cell distribution. The concomitant decrease of transactivator functions and increase of transinhibitor activity is responsible for ECM dysfunction, leading to aging/senescence in dermal fibroblasts.
- Published
- 2012
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- View/download PDF
32. Sox9/Sox6 and Sp1 are involved in the insulin-like growth factor-I-mediated upregulation of human type II collagen gene expression in articular chondrocytes.
- Author
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Renard E, Porée B, Chadjichristos C, Kypriotou M, Maneix L, Bigot N, Legendre F, Ollitrault D, De Crombrugghe B, Malléin-Gérin F, Moslemi S, Demoor M, Boumediene K, and Galéra P
- Subjects
- Animals, Blotting, Western, Cells, Cultured, Collagen Type II metabolism, Humans, Immunoglobulins genetics, Polymerase Chain Reaction, Rabbits, SOX9 Transcription Factor genetics, SOXD Transcription Factors genetics, Up-Regulation, Cartilage, Articular metabolism, Chondrocytes metabolism, Collagen Type II genetics, Gene Expression Regulation, Immunoglobulins metabolism, Insulin-Like Growth Factor I metabolism, SOX9 Transcription Factor metabolism, SOXD Transcription Factors metabolism
- Abstract
Type II collagen is a marker of articular cartilage encoded by the COL2A1 gene. The nature of the trans factors involved in the upregulation of this gene by insulin-like growth factor-I (IGF-I) remains unclear. We found that IGF-I increased type II collagen synthesis by a transcriptional control mechanism involving a 715-bp region within the COL2A1 first-intron specific enhancer. The overproduction of L-Sox5/Sox6/Sox9 and Sp1 and decoy experiments targeting these factors demonstrated their action in concert in IGF-I trans-activation. These results were supported by the data obtained in knockdown experiments in which siRNA against Sox9/Sox6 and Sp1 prevented the IGF-I-induced increase in collagen II production. Indeed, each of these trans-activators increased the expression of others. IGF-I increased the binding of Sox9 and Sp1/Sp3 to their cis elements in the enhancer, and we provide the first evidence of Sox9 interaction with the promoter by chromatin immunoprecipitation. Interactions with COL2A1 were also observed for Sp1, p300/CBP, and Tip60. Finally, a physical interaction between Sox9, p300, Sp3, and Sp1 was detected. These data demonstrate the role of Sox9, Sp1/Sp3, and euchromatin-associated factors (p300, Tip60) in the IGF-I-induced upregulation of COL2A1, indicating possible use of this growth factor in articular cartilage engineering applications to promote repair in patients with degenerative diseases, such as osteoarthritis.
- Published
- 2012
- Full Text
- View/download PDF
33. The p65 subunit of NF-κB inhibits COL1A1 gene transcription in human dermal and scleroderma fibroblasts through its recruitment on promoter by protein interaction with transcriptional activators (c-Krox, Sp1, and Sp3).
- Author
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Beauchef G, Bigot N, Kypriotou M, Renard E, Porée B, Widom R, Dompmartin-Blanchere A, Oddos T, Maquart FX, Demoor M, Boumediene K, and Galera P
- Subjects
- Adult, Child, Child, Preschool, Collagen Type I genetics, Collagen Type I, alpha 1 Chain, DNA-Binding Proteins genetics, Dermis pathology, Fibroblasts pathology, Gene Expression Regulation genetics, Humans, Male, Scleroderma, Localized pathology, Sp1 Transcription Factor genetics, Sp3 Transcription Factor genetics, Transcription Factor RelA genetics, Transcription Factors genetics, Collagen Type I biosynthesis, DNA-Binding Proteins metabolism, Dermis metabolism, Fibroblasts metabolism, Response Elements, Scleroderma, Localized metabolism, Sp1 Transcription Factor metabolism, Sp3 Transcription Factor metabolism, Transcription Factor RelA metabolism, Transcription Factors metabolism, Transcription, Genetic
- Abstract
Transcriptional mechanisms regulating type I collagen genes expression in physiopathological situations are not completely known. In this study, we have investigated the role of nuclear factor-κB (NF-κB) transcription factor on type I collagen expression in adult normal human (ANF) and scleroderma (SF) fibroblasts. We demonstrated that NF-κB, a master transcription factor playing a major role in immune response/apoptosis, down-regulates COL1A1 expression by a transcriptional control involving the -112/-61 bp sequence. This 51-bp region mediates the action of two zinc fingers, Sp1 (specific protein-1) and Sp3, acting as trans-activators of type I collagen expression in ANF and SF. Knockdown of each one of these trans factors by siRNA confirmed the trans-activating effect of Sp1/Sp3 and the p65 subunit of NF-κB trans-inhibiting effect on COL1A1 expression. Despite no existing κB consensus sequence in the COL1A1 promoter, we found that Sp1/Sp3/c-Krox and NF-κB bind and/or are recruited on the proximal promoter in chromatin immunoprecipitation (ChIP) assays. Attempts to elucidate whether interactions between Sp1/Sp3/c-Krox and p65 are necessary to mediate the NF-κB inhibitory effect on COL1A1 in ANF and SF were carried out; in this regard, immunoprecipitation assays revealed that they interact, and this was validated by re-ChIP. Finally, the knockdown of Sp1/Sp3/c-Krox prevents the p65 inhibitory effect on COL1A1 transcription in ANF, whereas only the siRNAs targeting Sp3 and c-Krox provoked the same effect in SF, suggesting that particular interactions are characteristic of the scleroderma phenotype. In conclusion, our findings highlight a new mechanism for COL1A1 transcriptional regulation by NF-κB, and these data could allow the development of new antifibrotic strategies.
- Published
- 2012
- Full Text
- View/download PDF
34. Visuospatial processing in memory for word location in writing.
- Author
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Le Bigot N, Passerault JM, and Olive T
- Subjects
- Adult, Humans, Neuropsychological Tests, Reading, Attention, Mental Recall, Space Perception, Visual Perception, Writing
- Abstract
Two experiments examined how visuospatial processing engaged during text composition intervenes in memory for word location. Experiment 1 showed that in contrast to participants who performed a spatial task concurrently with composing a text, participants who performed a concurrent visual task recalled fewer word locations after the composition. Consequently, it is hypothesized that writers process the written text in order to visually represent its physical layout, and that this representation is then used when locating words. Experiment 2 tested this hypothesis by comparing a standard composition condition (with the written trace) with a condition in which the written trace was suppressed during composition, and with a condition without written trace and with added visual noise. Memory for word location only decreased with visual noise, indicating that construction of the visual representation of the text does not rely on the written trace but involves visual working memory.
- Published
- 2012
- Full Text
- View/download PDF
35. Effects of handedness on visual sensitivity in perihand space.
- Author
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Le Bigot N and Grosjean M
- Subjects
- Adult, Humans, Photic Stimulation, Psychomotor Performance, Functional Laterality physiology, Hand, Visual Perception physiology
- Abstract
Recent studies have shown that changes in visual processing in perihand space are limited to the area around the right hand, at least in right-handers. One explanation for these findings is that perception is altered at locations where action is more likely to occur. To test this notion, we asked both right- and left-handers to perform an unspeeded visual discrimination task under four hand-position configurations: Left hand, right hand, both hands, or no hands near the display. Compared to the no-hands (control) condition, visual sensitivity (d') was higher in the dominant-hand condition for right-handers and higher in the dominant- as well as the non-dominant hand condition for left-handers. When both hands were near the display, sensitivity was similar to that in the dominant-hand condition for right-handers and to that in the non-dominant hand condition for left-handers. This shows that performance differed between the two handedness groups when their non-dominant hand was near the display (both alone and accompanied by their dominant hand). Thus, the pattern for left-handers did not correspond to a mirror image of the pattern for right-handers. In line with studies on bimanual action control, visual processing in perihand space seems to be determined by the different ways in which left- and right-handers use their hands.
- Published
- 2012
- Full Text
- View/download PDF
36. Asporin expression is highly regulated in human chondrocytes.
- Author
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Duval E, Bigot N, Hervieu M, Kou I, Leclercq S, Galéra P, Boumediene K, and Baugé C
- Subjects
- Aged, Aged, 80 and over, Binding Sites genetics, Blotting, Western, Cartilage, Articular cytology, Cell Dedifferentiation genetics, Cell Differentiation genetics, Cells, Cultured, Chondrocytes cytology, Chondrocytes drug effects, Down-Regulation drug effects, Electrophoretic Mobility Shift Assay, Extracellular Matrix Proteins metabolism, Gene Expression drug effects, Humans, Interleukin-1beta pharmacology, Middle Aged, Primary Cell Culture, Promoter Regions, Genetic genetics, Protein Binding, Reverse Transcriptase Polymerase Chain Reaction, Sp1 Transcription Factor genetics, Sp1 Transcription Factor metabolism, Transfection, Transforming Growth Factor beta1 pharmacology, Tumor Necrosis Factor-alpha pharmacology, Chondrocytes metabolism, Extracellular Matrix Proteins genetics, Gene Expression genetics
- Abstract
A significant association between a polymorphism in the D repeat of the gene encoding asporin and osteoarthritis, the most frequent of articular diseases, has been recently reported. The goal of the present study was to investigate the expression of this new class I small leucine-rich proteoglycan (SLRP) in human articular chondrocytes. First, we studied the modulation of asporin (ASPN) expression by cytokines by Western blot and reverse transcription-polymerase chain reaction. Interleukin-1β and tumor necrosis factor-α downregulated ASPN, whereas transforming growth factor-β1 (when incubated in a serum-free medium) upregulated it. Similarly to proinflammatory cytokines, chondrocyte dedifferentiation induced by a successive passages of cells was accompanied by a decreased asporin expression, whereas their redifferentiation by three-dimensional culture restored its expression. Finally, we found an important role of the transcription factor Sp1 in the regulation of ASPN expression. Sp1 ectopic expression increased ASPN mRNA level and promoter activity. In addition, using gene reporter assay and electrophoretic mobility shift assay, we showed that Sp1 mediated its effect through a region located between -473 and -140 bp upstream of the transcription start site in ASPN gene. In conclusion, this report is the first study on the regulation of asporin expression by different cytokines in human articular chondrocytes. Our data indicate that the expression of this gene is finely regulated in cartilage and suggest a major role of Sp1.
- Published
- 2011
- Full Text
- View/download PDF
37. Memory for words location in writing.
- Author
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Le Bigot N, Passerault JM, and Olive T
- Subjects
- Adult, Attention, Cognition, Humans, Linguistics, Reaction Time, Reading, Task Performance and Analysis, Vocabulary, Memory, Pattern Recognition, Visual, Recognition, Psychology, Space Perception, Verbal Behavior, Writing
- Abstract
In two experiments, we investigated memory for words location after writing a text. Experiment 1 demonstrated the existence of a memory for words location in writing by showing that participants who first composed a text and were then asked to locate words extracted from their text performed above a chance level established using a computer simulation, and better than participants who did not compose a text but were told the subject of the text. Experiment 2 showed that memory for words location in writing is mainly supported by a visuospatial representation of the text, as indicated by the lower recall of words location by participants who performed a visuospatial concurrent task at the time of the composition, compared with participants who performed a verbal concurrent task. The findings highlight the role of a spatial representation of the physical layout of the text and the role of such a memory in the writing process.
- Published
- 2009
- Full Text
- View/download PDF
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