44 results on '"Levet, C."'
Search Results
2. Computation of the Permeability Tensor of Non-Periodic Anisotropic Porous Media from 3D Images
- Author
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Scandelli, H., Ahmadi-Senichault, A., Levet, C., and Lachaud, J.
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- 2022
- Full Text
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3. Troubles périnéaux quatre ans après le premier accouchement : comparaison entre épisiotomie restrictive et systématique
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Fritel, X., Schaal, J.-P., Fauconnier, A., Bertrand, V., Levet, C., and Pigné, A.
- Published
- 2008
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4. Mistimed sleep disrupts the circadian regulation of the human transcriptome: 81
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Archer, S. N., Laing, E. E., Moller-Levet, C. S., van der Veen, D. R., Bucca, G., Lazar, A. S., Lo, J. C. Y., Santhi, N., Slak, A., Kabiljo, R., von Schantz, M., Smith, C. P., and Dijk, D. J.
- Published
- 2014
5. Pelvic floor disorders 4 years after first delivery: a comparative study of restrictive versus systematic episiotomy
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Fritel, X, Schaal, J P, Fauconnier, A, Bertrand, V, Levet, C, and Pigné, A
- Published
- 2008
6. Rhomboid family member 2 regulates cytoskeletal stress-associated Keratin 16
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Maruthappu, T, Chikh, A, Fell, B, Delaney, PJ, Brooke, MA, Levet, C, Moncada-Pazos, A, Ishida-Yamamoto, A, Blaydon, D, Waseem, A, Leigh, IM, Freeman, M, and Kelsell, DP
- Subjects
integumentary system - Abstract
Keratin 16 (K16) is a cytoskeletal scaffolding protein highly expressed at pressure-bearing sites of the mammalian footpad. It can be induced in hyperproliferative states such as wound healing, inflammation and cancer. Here we show that the inactive rhomboid protease RHBDF2 (iRHOM2) regulates thickening of the footpad epidermis through its interaction with K16. K16 expression is absent in the thinned footpads of irhom2(-/-) mice compared with irhom2(+/+)mice, due to reduced keratinocyte proliferation. Gain-of-function mutations in iRHOM2 underlie Tylosis with oesophageal cancer (TOC), characterized by palmoplantar thickening, upregulate K16 with robust downregulation of its type II keratin binding partner, K6. By orchestrating the remodelling and turnover of K16, and uncoupling it from K6, iRHOM2 regulates the epithelial response to physical stress. These findings contribute to our understanding of the molecular mechanisms underlying hyperproliferation of the palmoplantar epidermis in both physiological and disease states, and how this 'stress' keratin is regulated.
- Published
- 2017
7. 0006 GLUCOCORTICOID SIGNALLING PATHWAYS ARE AFFECTED BY MISTIMED SLEEP, DESPITE CORTISOL REMAINING RHYTHMIC
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Archer, SN, primary, Moller-Levet, C, additional, Santhi, N, additional, Laing, E, additional, and Dijk, DJ, additional
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- 2017
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8. Microstructure and gas-surface interaction studies of a 3D carbon/carbon composite in atmospheric entry plasma
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Levet, C., primary, Helber, B., additional, Couzi, J., additional, Mathiaud, J., additional, Gouriet, J.-B., additional, Chazot, O., additional, and Vignoles, G.L., additional
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- 2017
- Full Text
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9. Exon-array profiling unlocks clinically and biologically relevant gene signatures from formalin-fixed paraffin-embedded tumour samples.
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Hall, J. S., Leong, H. S., Armenoult, L. S. C., Newton, G. E., Valentine, H. R., Irlam, J. J., Möller-Levet, C., Sikand, K. A., Pepper, S. D., Miller, C. J., West, C. M. L., and Möller-Levet, C
- Subjects
MOLECULAR diagnosis ,CERVICAL cancer ,GENETIC regulation ,GENE expression ,EXONS (Genetics) ,HISTOLOGY - Abstract
Background: Degradation and chemical modification of RNA in formalin-fixed paraffin-embedded (FFPE) samples hamper their use in expression profiling studies. This study aimed to show that useful information can be obtained by Exon-array profiling archival FFPE tumour samples.Methods: Nineteen cervical squamous cell carcinoma (SCC) and 9 adenocarcinoma (AC) FFPE samples (10-16-year-old) were profiled using Affymetrix Exon arrays. The gene signature derived was tested on a fresh-frozen non-small cell lung cancer (NSCLC) series. Exploration of biological networks involved gene set enrichment analysis (GSEA). Differential gene expression was confirmed using Quantigene, a multiplex bead-based alternative to qRT-PCR.Results: In all, 1062 genes were higher in SCC vs AC, and 155 genes higher in AC. The 1217-gene signature correctly separated 58 NSCLC into SCC and AC. A gene network centered on hepatic nuclear factor and GATA6 was identified in AC, suggesting a role in glandular cell differentiation of the cervix. Quantigene analysis of the top 26 differentially expressed genes correctly partitioned cervix samples as SCC or AC.Conclusion: FFPE samples can be profiled using Exon arrays to derive gene expression signatures that are sufficiently robust to be applied to independent data sets, identify novel biology and design assays for independent platform validation. [ABSTRACT FROM AUTHOR]- Published
- 2011
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10. Drosophila p53 isoforms differentially regulate apoptosis and apoptosis-induced proliferation
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Dichtel-Danjoy, M-L, primary, Ma, D, additional, Dourlen, P, additional, Chatelain, G, additional, Napoletano, F, additional, Robin, M, additional, Corbet, M, additional, Levet, C, additional, Hafsi, H, additional, Hainaut, P, additional, Ryoo, H D, additional, Bourdon, J-C, additional, and Mollereau, B, additional
- Published
- 2012
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11. Pelvic floor disorders 4 years after first delivery: a comparative study of restrictive versus systematic episiotomy
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Fritel, X, primary, Schaal, JP, additional, Fauconnier, A, additional, Bertrand, V, additional, Levet, C, additional, and Pigné, A, additional
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- 2007
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12. Exploiting sample variability to enhance multivariate analysis of microarray data
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Moller-Levet, C. S., primary, West, C. M., additional, and Miller, C. J., additional
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- 2007
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13. Drosophila p53 isoforms differentially regulate apoptosis and apoptosis-induced proliferation.
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Dichtel-Danjoy, M-L, Ma, D, Dourlen, P, Chatelain, G, Napoletano, F, Robin, M, Corbet, M, Levet, C, Hafsi, H, Hainaut, P, Ryoo, H D, Bourdon, J-C, and Mollereau, B
- Subjects
DROSOPHILA ,APOPTOSIS ,CELL proliferation ,AUTOPHAGY ,ADAPTOR proteins ,DISEASE risk factors - Abstract
Irradiated or injured cells enter apoptosis, and in turn, promote proliferation of surrounding unaffected cells. In Drosophila, apoptotic cells have an active role in proliferation, where the caspase Dronc and p53 induce mitogen expression and growth in the surrounding tissues. The Drosophila p53 gene structure is conserved and encodes at least two protein isoforms: a full-length isoform (Dp53) and an N-terminally truncated isoform (DΔNp53). Historically, DΔNp53 was the first p53 isoform identified and was thought to be responsible for all p53 biological activities. It was shown that DΔNp53 induces apoptosis by inducing the expression of IAP antagonists, such as Reaper. Here we investigated the roles of Dp53 and DΔNp53 in apoptosis and apoptosis-induced proliferation. We found that both isoforms were capable of activating apoptosis, but that they each induced distinct IAP antagonists. Expression of DΔNp53 induced Wingless (Wg) expression and enhanced proliferation in both 'undead cells' and in 'genuine' apoptotic cells. In contrast to DΔNp53, Dp53 did not induce Wg expression in the absence of the endogenous p53 gene. Thus, we propose that DΔNp53 is the main isoform that regulates apoptosis-induced proliferation. Understanding the roles of Drosophila p53 isoforms in apoptosis and in apoptosis-induced proliferation may shed new light on the roles of p53 isoforms in humans, with important implications in cancer biology. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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14. The curse of normalization
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Wolkenhauer, O., Möller-Levet, C., and Sanchez-Cabo, F.
- Abstract
Despite its enormous promise to further our understanding of cellular processes involved in the regulation of gene expression, microarray technology generates data for which statistical pre-processing has become a necessity before any interpretation of data can begin. The process by which we distinguish (and remove) non-biological variation from biological variation is called normalization. With a multitude of experimental designs, techniques and technologies influencing the acquisition of data, numerous approaches to normalization have been proposed in the literature. The purpose of this short review is not to add to the many suggestions that have been made, but to discuss some of the difficulties we encounter when analysing microarray data. Copyright © 2002 John Wiley & Sons, Ltd.
- Published
- 2002
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15. Fuzzy clustering of short time-series and unevenly distributed sampling points
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Möller-Levet, C. S., Frank Klawonn, Cho, K. -H, and Wolkenhauer, O.
16. Drosophila p53 isoforms differentially regulate apoptosis and apoptosis-induced proliferation
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Hyung Don Ryoo, Clemence Levet, Pierre Hainaut, Francesco Napoletano, Marion Robin, M. Corbet, Jean-Christophe Bourdon, Bertrand Mollereau, Dali Ma, Marie-Laure Dichtel-Danjoy, Gilles Chatelain, Hind Hafsi, Pierre Dourlen, Dichtel-Danjoy, M. -L., Ma, D., Dourlen, P., Chatelain, G., Napoletano, F., Robin, M., Corbet, M., Levet, C., Hafsi, H., Hainaut, P., Ryoo, H. D., Bourdon, J. -C., Mollereau, B., Laboratoire de Biologie Moléculaire de la Cellule (LBMC), Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon, Molecular Carcinogenesis Group, International Agency for Cancer Research (IACR), Sect Mech Carcinogenesis, Department of Cell Biology, New York University [New York] (NYU), NYU System (NYU)-NYU System (NYU), Division of Medical Sciences, University of Dundee-Centre for Oncology and Molecular Medicine, École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)
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p53 ,Gene isoform ,apoptosis ,Drosophila ,hid ,reaper ,regeneration ,Animals ,Animals, Genetically Modified ,Apoptosis ,Cell Growth Processes ,Protein Isoforms ,Signal Transduction ,Tumor Suppressor Protein p53 ,Molecular Biology ,Cell Biology ,[SDV]Life Sciences [q-bio] ,Genetically Modified ,Endogeny ,03 medical and health sciences ,0302 clinical medicine ,Gene ,Caspase ,030304 developmental biology ,Original Paper ,0303 health sciences ,Cell Growth Processe ,biology ,Animal ,Regeneration (biology) ,Apoptosi ,Protein Isoform ,Cell biology ,030220 oncology & carcinogenesis ,Mitogen-activated protein kinase ,biology.protein ,Signal transduction - Abstract
Irradiated or injured cells enter apoptosis, and in turn, promote proliferation of surrounding unaffected cells. In Drosophila, apoptotic cells have an active role in proliferation, where the caspase Dronc and p53 induce mitogen expression and growth in the surrounding tissues. The Drosophila p53 gene structure is conserved and encodes at least two protein isoforms: a full-length isoform (Dp53) and an N-terminally truncated isoform (DDNp53). Historically, DDNp53 was the first p53 isoform identified and was thought to be responsible for all p53 biological activities. It was shown that DDNp53 induces apoptosis by inducing the expression of IAP antagonists, such as Reaper. Here we investigated the roles of Dp53 and DDNp53 in apoptosis and apoptosis- induced proliferation. We found that both isoforms were capable of activating apoptosis, but that they each induced distinct IAP antagonists. Expression of DDNp53 induced Wingless (Wg) expression and enhanced proliferation in both ‘undead cells’ and in ‘genuine’ apoptotic cells. In contrast to DDNp53, Dp53 did not induce Wg expression in the absence of the endogenous p53 gene. Thus, we propose that DDNp53 is the main isoform that regulates apoptosis-induced proliferation. Understanding the roles of Drosophila p53 isoforms in apoptosis and in apoptosis-induced proliferation may shed new light on the roles of p53 isoforms in humans, with important implications in cancer biology.
- Published
- 2012
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17. Eta-secretase-like processing of the amyloid precursor protein (APP) by the rhomboid protease RHBDL4.
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Penalva YCM, Paschkowsky S, Recinto SJ, Duchesne A, Hammond T, Spiegler P, Jansen G, Levet C, Charron F, Freeman M, McKinney RA, Trempe JF, and Munter LM
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- Animals, Humans, Mice, Endoplasmic Reticulum metabolism, HEK293 Cells, Membrane Proteins metabolism, Membrane Proteins genetics, Mice, Knockout, Proteolysis, Amyloid beta-Protein Precursor metabolism, Amyloid beta-Protein Precursor genetics, Amyloid Precursor Protein Secretases metabolism, Amyloid Precursor Protein Secretases genetics
- Abstract
The amyloid precursor protein (APP) is a key protein in Alzheimer's disease synthesized in the endoplasmic reticulum (ER) and translocated to the plasma membrane where it undergoes proteolytic cleavages by several proteases. Conversely, to other known proteases, we previously elucidated rhomboid protease RHBDL4 as a novel APP processing enzyme where several cleavages likely occur already in the ER. Interestingly, the pattern of RHBDL4-derived large APP C-terminal fragments resembles those generated by the η-secretase or MT5-MMP, which was described to generate so-called Aη fragments. The similarity in large APP C-terminal fragments between both proteases raised the question of whether RHBDL4 may contribute to η-secretase activity and Aη-like fragments. Here, we identified two cleavage sites of RHBDL4 in APP by mass spectrometry, which, intriguingly, lie in close proximity to the MT5-MMP cleavage sites. Indeed, we observed that RHBDL4 generates Aη-like fragments in vitro without contributions of α-, β-, or γ-secretases. Such Aη-like fragments are likely generated in the ER since RHBDL4-derived APP-C-terminal fragments do not reach the cell surface. Inherited, familial APP mutations appear to not affect this processing pathway. In RHBDL4 knockout mice, we observed increased cerebral full-length APP in comparison to wild type (WT) in support of RHBDL4 being a physiologically relevant protease for APP. Furthermore, we found secreted Aη fragments in dissociated mixed cortical cultures from WT mice, however significantly fewer Aη fragments in RHBDL4 knockout cultures. Our data underscores that RHBDL4 contributes to the η-secretease-like processing of APP and that RHBDL4 is a physiologically relevant protease for APP., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article, (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2024
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18. Erratum: Extensive dynamic changes in the human transcriptome and its circadian organization during prolonged bed rest.
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Archer SN, Möller-Levet C, Bonmatí-Carrión MÁ, Laing EE, and Dijk DJ
- Abstract
[This corrects the article DOI: 10.1016/j.isci.2024.109331.]., (© 2024 The Author(s).)
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- 2024
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19. Extensive dynamic changes in the human transcriptome and its circadian organization during prolonged bed rest.
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Archer SN, Möller-Levet C, Bonmatí-Carrión MÁ, Laing EE, and Dijk DJ
- Abstract
Physiological and molecular processes including the transcriptome change across the 24-h day, driven by molecular circadian clocks and behavioral and systemic factors. It is not known how the temporal organization of the human transcriptome responds to a long-lasting challenge. This may, however, provide insights into adaptation, disease, and recovery. We investigated the human 24-h time series transcriptome in 20 individuals during a 90-day constant bed rest protocol. We show that the protocol affected 91% of the transcriptome with 76% of the transcriptome still affected after 10 days of recovery. Dimensionality-reduction approaches revealed that many affected transcripts were associated with mRNA translation and immune function. The number, amplitude, and phase of rhythmic transcripts, including clock genes, varied significantly across the challenge. These findings of long-lasting changes in the temporal organization of the transcriptome have implications for understanding the mechanisms underlying health consequences of conditions such as microgravity and bed rest., Competing Interests: The authors declare no competing interests., (© 2024 The Authors.)
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- 2024
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20. Cleavage of the pseudoprotease iRhom2 by the signal peptidase complex reveals an ER-to-nucleus signaling pathway.
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Dulloo I, Tellier M, Levet C, Chikh A, Zhang B, Blaydon DC, Webb CM, Kelsell DP, and Freeman M
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- Animals, Humans, Mice, Carrier Proteins genetics, Carrier Proteins metabolism, Membrane Proteins genetics, Membrane Proteins metabolism, Serine Endopeptidases genetics, Serine Endopeptidases metabolism, Psoriasis genetics, Signal Transduction
- Abstract
iRhoms are pseudoprotease members of the rhomboid-like superfamily and are cardinal regulators of inflammatory and growth factor signaling; they function primarily by recognizing transmembrane domains of their clients. Here, we report a mechanistically distinct nuclear function of iRhoms, showing that both human and mouse iRhom2 are non-canonical substrates of signal peptidase complex (SPC), the protease that removes signal peptides from secreted proteins. Cleavage of iRhom2 generates an N-terminal fragment that enters the nucleus and modifies the transcriptome, in part by binding C-terminal binding proteins (CtBPs). The biological significance of nuclear iRhom2 is indicated by elevated levels in skin biopsies of patients with psoriasis, tylosis with oesophageal cancer (TOC), and non-epidermolytic palmoplantar keratoderma (NEPPK); increased iRhom2 cleavage in a keratinocyte model of psoriasis; and nuclear iRhom2 promoting proliferation of keratinocytes. Overall, this work identifies an unexpected SPC-dependent ER-to-nucleus signaling pathway and demonstrates that iRhoms can mediate nuclear signaling., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)
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- 2024
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21. The dysfunctional immune response in renal cell carcinoma correlates with changes in the metabolic landscape of ccRCC during disease progression.
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Annels NE, Denyer M, Nicol D, Hazell S, Silvanto A, Crockett M, Hussain M, Moller-Levet C, and Pandha H
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- Humans, Neoplasm Recurrence, Local, Disease Progression, Immunity, Carcinoma, Renal Cell pathology, Kidney Neoplasms pathology
- Abstract
Renal cell carcinoma is an immunogenic tumour with a prominent dysfunctional immune cell infiltrate, unable to control tumour growth. Although tyrosine kinase inhibitors and immunotherapy have improved the outlook for some patients, many individuals are non-responders or relapse despite treatment. The hostile metabolic environment in RCC affects the ability of T-cells to maintain their own metabolic programme constraining T-cell immunity in RCC. We investigated the phenotype, function and metabolic capability of RCC TILs correlating this with clinicopathological features of the tumour and metabolic environment at the different disease stages. Flow cytometric analysis of freshly isolated TILs showed the emergence of exhausted T-cells in advanced disease based on their PD-1
high and CD39 expression and reduced production of inflammatory cytokines upon in vitro stimulation. Exhausted T-cells from advanced stage disease also displayed an overall phenotype of metabolic insufficiency, characterized by mitochondrial alterations and defects in glucose uptake. Nanostring nCounter cancer metabolism assay on RNA obtained from 30 ccRCC cases revealed significant over-expression of metabolic genes even at early stage disease (pT1-2), while at pT3-4 and the locally advanced thrombi stages, there was an overall decrease in differentially expressed metabolic genes. Notably, the gene PPARGC1A was the most significantly down-regulated gene from pT1-2 to pT3-4 RCC which correlated with loss of mitochondrial function in tumour-infiltrating T-cells evident at this tumour stage. Down-regulation of PPARGC1A into stage pT3-4 may be the 'tipping-point' in RCC disease progression, modulating immune activity in ccRCC and potentially reducing the efficacy of immunotherapies in RCC and poorer patient outcomes., (© 2023. The Author(s).)- Published
- 2023
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22. A post-transcriptional regulatory landscape of aging in the female mouse hippocampus.
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Winsky-Sommerer R, King HA, Iadevaia V, Möller-Levet C, and Gerber AP
- Abstract
Aging is associated with substantial physiological changes and constitutes a major risk factor for neurological disorders including dementia. Alterations in gene expression upon aging have been extensively studied; however, an in-depth characterization of post-transcriptional regulatory events remains elusive. Here, we profiled the age-related changes of the transcriptome and translatome in the female mouse hippocampus by RNA sequencing of total RNA and polysome preparations at four ages (3-, 6-, 12-, 20-month-old); and we implemented a variety of bioinformatics approaches to unravel alterations in transcript abundance, alternative splicing, and polyadenylation site selection. We observed mostly well-coordinated transcriptome and translatome expression signatures across age including upregulation of transcripts related to immune system processes and neuroinflammation, though transcripts encoding ribonucleoproteins or associated with mitochondrial functions, calcium signaling and the cell-cycle displayed substantial discordant profiles, suggesting translational control associated with age-related deficits in hippocampal-dependent behavior. By contrast, alternative splicing was less preserved, increased with age and was associated with distinct functionally-related transcripts encoding proteins acting at synapses/dendrites, RNA-binding proteins; thereby predicting regulatory roles for RBM3 and CIRBP. Only minor changes in polyadenylation site selection were identified, indicating pivotal 3'-end selection in young adults compared to older groups. Overall, our study provides a comprehensive resource of age-associated post-transcriptional regulatory events in the mouse hippocampus, enabling further examination of the molecular features underlying age-associated neurological diseases., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Winsky-Sommerer, King, Iadevaia, Möller-Levet and Gerber.)
- Published
- 2023
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23. The mammalian rhomboid protein RHBDL4 protects against endoplasmic reticulum stress by regulating the morphology and distribution of ER sheets.
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Lastun VL, Levet C, and Freeman M
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- Animals, Cytoskeleton metabolism, Endoplasmic Reticulum genetics, Endoplasmic Reticulum metabolism, Membrane Proteins genetics, Membrane Proteins metabolism, Mice, Endoplasmic Reticulum Stress genetics
- Abstract
In metazoans, the architecture of the endoplasmic reticulum (ER) differs between cell types and undergoes major changes throughout the cell cycle and according to physiological needs. Although much is known about how the different ER morphologies are generated and maintained, especially ER tubules, how context-dependent changes in ER shape and distribution are regulated and the factors involved are less well characterized, as are the factors that contribute to the positioning of the ER within the cell. By overexpression and KO experiments, we show that the levels of RHBDL4, an ER-resident rhomboid protease, modulate the shape and distribution of the ER, especially during conditions that require rapid changes in the ER sheet distribution, such as ER stress. We demonstrate that RHBDL4 interacts with cytoskeleton-linking membrane protein 63 (CLIMP-63), a protein involved in ER sheet stabilization, as well as with the cytoskeleton. Furthermore, we found that mice lacking RHBDL4 are sensitive to ER stress and develop liver steatosis, a phenotype associated with unresolved ER stress. Taken together, these data suggest a new physiological role for RHBDL4 and also imply that this function does not require its enzymatic activity., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2022
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24. HOX and PBX gene dysregulation as a therapeutic target in glioblastoma multiforme.
- Author
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Arunachalam E, Rogers W, Simpson GR, Möller-Levet C, Bolton G, Ismael M, Smith C, Keegen K, Bagwan I, Brend T, Short SC, Hong B, Otani Y, Kaur B, Annels N, Morgan R, and Pandha H
- Subjects
- Adult, Animals, Cell Line, Tumor, Genes, Homeobox, Humans, Mice, Peptides genetics, Tissue Distribution, Brain Neoplasms drug therapy, Brain Neoplasms genetics, Glioblastoma drug therapy, Glioblastoma therapy
- Abstract
Background: Glioblastoma multiforme (GBM) is the most common high-grade malignant brain tumour in adults and arises from the glial cells in the brain. The prognosis of treated GBM remains very poor with 5-year survival rates of 5%, a figure which has not improved over the last few decades. Currently, there is a modest 14-month overall median survival in patients undergoing maximum safe resection plus adjuvant chemoradiotherapy. HOX gene dysregulation is now a widely recognised feature of many malignancies., Methods: In this study we have focused on HOX gene dysregulation in GBM as a potential therapeutic target in a disease with high unmet need., Results: We show significant dysregulation of these developmentally crucial genes and specifically that HOX genes A9, A10, C4 and D9 are strong candidates for biomarkers and treatment targets for GBM and GBM cancer stem cells. We evaluated a next generation therapeutic peptide, HTL-001, capable of targeting HOX gene over-expression in GBM by disrupting the interaction between HOX proteins and their co-factor, PBX. HTL-001 induced both caspase-dependent and -independent apoptosis in GBM cell lines., Conclusion: In vivo biodistribution studies confirmed that the peptide was able to cross the blood brain barrier. Systemic delivery of HTL-001 resulted in improved control of subcutaneous murine and human xenograft tumours and improved survival in a murine orthotopic model., (© 2022. The Author(s).)
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- 2022
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25. iRhom pseudoproteases regulate ER stress-induced cell death through IP 3 receptors and BCL-2.
- Author
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Dulloo I, Atakpa-Adaji P, Yeh YC, Levet C, Muliyil S, Lu F, Taylor CW, and Freeman M
- Subjects
- Apoptosis, Carrier Proteins metabolism, Endoplasmic Reticulum metabolism, Endoplasmic Reticulum Stress, Proto-Oncogene Proteins c-bcl-2 metabolism
- Abstract
The folding capacity of membrane and secretory proteins in the endoplasmic reticulum (ER) can be challenged by physiological and pathological perturbations, causing ER stress. If unresolved, this leads to cell death. We report a role for iRhom pseudoproteases in controlling apoptosis due to persistent ER stress. Loss of iRhoms causes cells to be resistant to ER stress-induced apoptosis. iRhom1 and iRhom2 interact with IP
3 receptors, critical mediators of intracellular Ca2+ signalling, and regulate ER stress-induced transport of Ca2+ into mitochondria, a primary trigger of mitochondrial membrane depolarisation and cell death. iRhoms also bind to the anti-apoptotic regulator BCL-2, attenuating the inhibitory interaction between BCL-2 and IP3 receptors, which promotes ER Ca2+ release. The discovery of the participation of iRhoms in the control of ER stress-induced cell death further extends their potential pathological significance to include diseases dependent on protein misfolding and aggregation., (© 2022. The Author(s).)- Published
- 2022
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26. Vitamins D 2 and D 3 Have Overlapping But Different Effects on the Human Immune System Revealed Through Analysis of the Blood Transcriptome.
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Durrant LR, Bucca G, Hesketh A, Möller-Levet C, Tripkovic L, Wu H, Hart KH, Mathers JC, Elliott RM, Lanham-New SA, and Smith CP
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- Cholecalciferol therapeutic use, Dietary Supplements, Female, Humans, Immune System, Vitamin D pharmacology, Vitamins therapeutic use, Ergocalciferols, Transcriptome
- Abstract
Vitamin D is best known for its role in maintaining bone health and calcium homeostasis. However, it also exerts a broad range of extra-skeletal effects on cellular physiology and on the immune system. Vitamins D
2 and D3 share a high degree of structural similarity. Functional equivalence in their vitamin D-dependent effects on human physiology is usually assumed but has in fact not been well defined experimentally. In this study we seek to redress the gap in knowledge by undertaking an in-depth examination of changes in the human blood transcriptome following supplementation with physiological doses of vitamin D2 and D3 . Our work extends a previously published randomized placebo-controlled trial that recruited healthy white European and South Asian women who were given 15 µg of vitamin D2 or D3 daily over 12 weeks in wintertime in the UK (Nov-Mar) by additionally determining changes in the blood transcriptome over the intervention period using microarrays. An integrated comparison of the results defines both the effect of vitamin D3 or D2 on gene expression, and any influence of ethnic background. An important aspect of this analysis was the focus on the changes in expression from baseline to the 12-week endpoint of treatment within each individual, harnessing the longitudinal design of the study. Whilst overlap in the repertoire of differentially expressed genes was present in the D2 or D3 -dependent effects identified, most changes were specific to either one vitamin or the other. The data also pointed to the possibility of ethnic differences in the responses. Notably, following vitamin D3 supplementation, the majority of changes in gene expression reflected a down-regulation in the activity of genes, many encoding pathways of the innate and adaptive immune systems, potentially shifting the immune system to a more tolerogenic status. Surprisingly, gene expression associated with type I and type II interferon activity, critical to the innate response to bacterial and viral infections, differed following supplementation with either vitamin D2 or vitamin D3 , with only vitamin D3 having a stimulatory effect. This study suggests that further investigation of the respective physiological roles of vitamin D2 and vitamin D3 is warranted., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Durrant, Bucca, Hesketh, Möller-Levet, Tripkovic, Wu, Hart, Mathers, Elliott, Lanham-New and Smith.)- Published
- 2022
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27. HOXB9 Overexpression Promotes Colorectal Cancer Progression and Is Associated with Worse Survival in Liver Resection Patients for Colorectal Liver Metastases.
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Martinou E, Moller-Levet C, Karamanis D, Bagwan I, and Angelidi AM
- Subjects
- Adult, Aged, Aged, 80 and over, Biomarkers, Tumor genetics, Cell Proliferation genetics, Cohort Studies, Colorectal Neoplasms pathology, Disease Progression, Down-Regulation genetics, Epithelial-Mesenchymal Transition genetics, Female, Gene Expression Regulation, Neoplastic genetics, Humans, Liver pathology, Liver Neoplasms pathology, Male, Middle Aged, Mutation genetics, Neoplasm Metastasis pathology, Up-Regulation genetics, Colorectal Neoplasms genetics, Homeodomain Proteins genetics, Liver Neoplasms genetics, Neoplasm Metastasis genetics
- Abstract
As is known, HOXB9 is an important factor affecting disease progression and overall survival (OS) in cancer. However, its role in colorectal cancer (CRC) remains unclear. We aimed to explore the role of HOXB9 in CRC progression and its association with OS in colorectal liver metastases (CRLM). We analysed differential HOXB9 expression in CRC using the Tissue Cancer Genome Atlas database (TCGA). We modulated HOXB9 expression in vitro to assess its impact on cell proliferation and epithelial-mesenchymal transition (EMT). Lastly, we explored the association of HOXB9 protein expression with OS, using an institutional patient cohort ( n = 110) who underwent liver resection for CRLM. Furthermore, HOXB9 was upregulated in TCGA-CRC ( n = 644) vs. normal tissue ( n = 51) and its expression levels were elevated in KRAS mutations ( p < 0.0001). In vitro, HOXB9 overexpression increased cell proliferation ( p < 0.001) and upregulated the mRNA expression of EMT markers ( VIM , CDH2 , ZEB1 , ZEB2 , SNAI1 and SNAI2 ) while downregulated CDH1 , ( p < 0.05 for all comparisons). Conversely, HOXB9 silencing disrupted cell growth ( p < 0.0001). High HOXB9 expression (HR = 3.82, 95% CI: 1.59-9.2, p = 0.003) was independently associated with worse OS in CRLM-HOXB9-expressing patients after liver resection. In conclusion, HOXB9 may be associated with worse OS in CRLM and may promote CRC progression, whereas HOXB9 silencing may inhibit CRC growth.
- Published
- 2022
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28. Novel stress granule-like structures are induced via a paracrine mechanism during viral infection.
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Iadevaia V, Burke JM, Eke L, Moller-Levet C, Parker R, and Locker N
- Subjects
- Animals, Calicivirus, Feline immunology, Cats, Poly-ADP-Ribose Binding Proteins immunology, RNA Recognition Motif Proteins metabolism, Virus Replication physiology, Caliciviridae Infections immunology, Stress Granules immunology
- Abstract
To rapidly adapt to stresses such as infections, cells have evolved several mechanisms, which include the activation of stress response pathways and the innate immune response. These stress responses result in the rapid inhibition of translation and condensation of stalled mRNAs with RNA-binding proteins and signalling components into cytoplasmic biocondensates called stress granules (SGs). Increasing evidence suggests that SGs contribute to antiviral defence, and thus viruses need to evade these responses to propagate. We previously showed that feline calicivirus (FCV) impairs SG assembly by cleaving the scaffolding protein G3BP1. We also observed that uninfected bystander cells assembled G3BP1-positive granules, suggesting a paracrine response triggered by infection. We now present evidence that virus-free supernatant generated from infected cells can induce the formation of SG-like foci, which we name paracrine granules. They are linked to antiviral activity and exhibit specific kinetics of assembly-disassembly, and protein and RNA composition that are different from canonical SGs. We propose that this paracrine induction reflects a novel cellular defence mechanism to limit viral propagation and promote stress responses in bystander cells., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2022. Published by The Company of Biologists Ltd.)
- Published
- 2022
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29. Murine Norovirus Infection Results in Anti-inflammatory Response Downstream of Amino Acid Depletion in Macrophages.
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Brocard M, Lu J, Hall B, Borah K, Moller-Levet C, Georgana I, Sorgeloos F, Beste DJV, Goodfellow IG, and Locker N
- Subjects
- Activating Transcription Factor 2 metabolism, Animals, Antiviral Agents, Caliciviridae Infections metabolism, Cell Line, Eukaryotic Initiation Factor-2 metabolism, Immunity, Innate immunology, Inflammation immunology, Interferons, Macrophages immunology, Mice, Norovirus pathogenicity, Protein Serine-Threonine Kinases metabolism, RAW 264.7 Cells, RNA, Double-Stranded genetics, Signal Transduction immunology, Viral Nonstructural Proteins metabolism, Virus Replication genetics, Caliciviridae Infections immunology, Macrophages virology
- Abstract
Murine norovirus (MNV) infection results in a late translation shutoff that is proposed to contribute to the attenuated and delayed innate immune response observed both in vitro and in vivo. Recently, we further demonstrated the activation of the α subunit of eukaryotic initiation factor 2 (eIF2α) kinase GCN2 during MNV infection, which has been previously linked to immunomodulation and resistance to inflammatory signaling during metabolic stress. While viral infection is usually associated with activation of double-stranded RNA (dsRNA) binding pattern recognition receptor PKR, we hypothesized that the establishment of a metabolic stress in infected cells is a proviral event, exploited by MNV to promote replication through weakening the activation of the innate immune response. In this study, we used multi-omics approaches to characterize cellular responses during MNV replication. We demonstrate the activation of pathways related to the integrated stress response, a known driver of anti-inflammatory phenotypes in macrophages. In particular, MNV infection causes an amino acid imbalance that is associated with GCN2 and ATF2 signaling. Importantly, this reprogramming lacks the features of a typical innate immune response, with the ATF/CHOP target GDF15 contributing to the lack of antiviral responses. We propose that MNV-induced metabolic stress supports the establishment of host tolerance to viral replication and propagation. IMPORTANCE During viral infection, host defenses are typically characterized by the secretion of proinflammatory autocrine and paracrine cytokines, potentiation of the interferon (IFN) response, and induction of the antiviral response via activation of JAK and Stat signaling. To avoid these and propagate, viruses have evolved strategies to evade or counteract host sensing. In this study, we demonstrate that murine norovirus controls the antiviral response by activating a metabolic stress response that activates the amino acid response and impairs inflammatory signaling. This highlights novel tools in the viral countermeasures arsenal and demonstrates the importance of the currently poorly understood metabolic reprogramming occurring during viral infections.
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- 2021
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30. ADAM17-triggered TNF signalling protects the ageing Drosophila retina from lipid droplet-mediated degeneration.
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Muliyil S, Levet C, Düsterhöft S, Dulloo I, Cowley SA, and Freeman M
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- ADAM17 Protein genetics, Animals, Drosophila Proteins genetics, Drosophila melanogaster, Humans, Lipid Droplets pathology, Membrane Proteins genetics, Neuroglia pathology, Reactive Oxygen Species metabolism, Retina pathology, Tumor Necrosis Factor-alpha genetics, ADAM17 Protein metabolism, Drosophila Proteins metabolism, Lipid Droplets metabolism, Membrane Proteins metabolism, Neuroglia metabolism, Retina metabolism, Signal Transduction, Tumor Necrosis Factor-alpha metabolism
- Abstract
Animals have evolved multiple mechanisms to protect themselves from the cumulative effects of age-related cellular damage. Here, we reveal an unexpected link between the TNF (tumour necrosis factor) inflammatory pathway, triggered by the metalloprotease ADAM17/TACE, and a lipid droplet (LD)-mediated mechanism of protecting retinal cells from age-related degeneration. Loss of ADAM17, TNF and the TNF receptor Grindelwald in pigmented glial cells of the Drosophila retina leads to age-related degeneration of both glia and neurons, preceded by an abnormal accumulation of glial LDs. We show that the glial LDs initially buffer the cells against damage caused by glial and neuronally generated reactive oxygen species (ROS), but that in later life the LDs dissipate, leading to the release of toxic peroxidated lipids. Finally, we demonstrate the existence of a conserved pathway in human iPS-derived microglia-like cells, which are central players in neurodegeneration. Overall, we have discovered a pathway mediated by TNF signalling acting not as a trigger of inflammation, but as a cytoprotective factor in the retina., (© 2020 The Authors. Published under the terms of the CC BY 4.0 license.)
- Published
- 2020
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31. A genome-wide association study in mice reveals a role for Rhbdf2 in skeletal homeostasis.
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Levy R, Levet C, Cohen K, Freeman M, Mott R, Iraqi F, and Gabet Y
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- Animals, Computer Simulation, Female, Fractures, Bone genetics, Genotype, Homeostasis, Male, Mice, Mice, Inbred C57BL, Mice, Knockout, Phenotype, Quantitative Trait Loci, RNA-Seq, X-Ray Microtomography, Bone Density, Carrier Proteins genetics, Genome-Wide Association Study, Osteoporosis genetics
- Abstract
Low bone mass and an increased risk of fracture are predictors of osteoporosis. Individuals who share the same bone-mineral density (BMD) vary in their fracture risk, suggesting that microstructural architecture is an important determinant of skeletal strength. Here, we utilized the rich diversity of the Collaborative Cross mice to identify putative causal genes that contribute to the risk of fractures. Using microcomputed tomography, we examined key structural features that pertain to bone quality in the femoral cortical and trabecular compartments of male and female mice. We estimated the broad-sense heritability to be 50-60% for all examined traits, and we identified five quantitative trait loci (QTL) significantly associated with six traits. We refined each QTL by combining information inferred from the ancestry of the mice, ranging from RNA-Seq data and published literature to shortlist candidate genes. We found strong evidence for new candidate genes, particularly Rhbdf2, whose close association with the trabecular bone volume fraction and number was strongly suggested by our analyses. We confirmed our findings with mRNA expression assays of Rhbdf2 in extreme-phenotype mice, and by phenotyping bones of Rhbdf2 knockout mice. Our results indicate that Rhbdf2 plays a decisive role in bone mass accrual and microarchitecture.
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- 2020
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32. Neutrophil and Macrophage Cell Surface Colony-Stimulating Factor 1 Shed by ADAM17 Drives Mouse Macrophage Proliferation in Acute and Chronic Inflammation.
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Tang J, Frey JM, Wilson CL, Moncada-Pazos A, Levet C, Freeman M, Rosenfeld ME, Stanley ER, Raines EW, and Bornfeldt KE
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- ADAM17 Protein deficiency, ADAM17 Protein genetics, Acute Disease, Animals, Carrier Proteins antagonists & inhibitors, Carrier Proteins genetics, Carrier Proteins metabolism, Cell Membrane metabolism, Cell Proliferation, Chronic Disease, Inflammation pathology, Macrophages pathology, Male, Mice, Mice, Inbred C57BL, Mice, Knockout, Models, Biological, Neutrophils pathology, Peritonitis metabolism, Peritonitis pathology, Receptors, LDL deficiency, Receptors, LDL genetics, Solubility, ADAM17 Protein metabolism, Inflammation metabolism, Macrophage Colony-Stimulating Factor metabolism, Macrophages metabolism, Neutrophils metabolism
- Abstract
Macrophages are prominent cells in acute and chronic inflammatory diseases. Recent studies highlight a role for macrophage proliferation post-monocyte recruitment under inflammatory conditions. Using an acute peritonitis model, we identify a significant defect in macrophage proliferation in mice lacking the leukocyte transmembrane protease ADAM17. The defect is associated with decreased levels of macrophage colony-stimulating factor 1 (CSF-1) in the peritoneum and is rescued by intraperitoneal injection of CSF-1. Cell surface CSF-1 (csCSF-1) is one of the substrates of ADAM17. We demonstrate that both infiltrated neutrophils and macrophages are major sources of csCSF-1. Furthermore, acute shedding of csCSF-1 following neutrophil extravasation is associated with elevated expression of iRhom2, a member of the rhomboid-like superfamily, which promotes ADAM17 maturation and trafficking to the neutrophil surface. Accordingly, deletion of hematopoietic iRhom2 is sufficient to prevent csCSF-1 release from neutrophils and macrophages and to prevent macrophage proliferation. In acute inflammation, csCSF-1 release and macrophage proliferation are self-limiting due to transient leukocyte recruitment and temporally restricted csCSF-1 expression. In chronic inflammation, such as atherosclerosis, the ADAM17-mediated lesional macrophage proliferative response is prolonged. Our results demonstrate a novel mechanism whereby ADAM17 promotes macrophage proliferation in states of acute and chronic inflammation., (Copyright © 2018 American Society for Microbiology.)
- Published
- 2018
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33. Translational control plays an important role in the adaptive heat-shock response of Streptomyces coelicolor.
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Bucca G, Pothi R, Hesketh A, Möller-Levet C, Hodgson DA, Laing EE, Stewart GR, and Smith CP
- Subjects
- Gene Expression Regulation, Bacterial, Polyribosomes metabolism, Streptomyces coelicolor metabolism, Transcription, Genetic, Heat-Shock Response genetics, Protein Biosynthesis, Streptomyces coelicolor genetics
- Abstract
Stress-induced adaptations require multiple levels of regulation in all organisms to repair cellular damage. In the present study we evaluated the genome-wide transcriptional and translational changes following heat stress exposure in the soil-dwelling model actinomycete bacterium, Streptomyces coelicolor. The combined analysis revealed an unprecedented level of translational control of gene expression, deduced through polysome profiling, in addition to transcriptional changes. Our data show little correlation between the transcriptome and 'translatome'; while an obvious downward trend in genome wide transcription was observed, polysome associated transcripts following heat-shock showed an opposite upward trend. A handful of key protein players, including the major molecular chaperones and proteases were highly induced at both the transcriptional and translational level following heat-shock, a phenomenon known as 'potentiation'. Many other transcripts encoding cold-shock proteins, ABC-transporter systems, multiple transcription factors were more highly polysome-associated following heat stress; interestingly, these protein families were not induced at the transcriptional level and therefore were not previously identified as part of the stress response. Thus, stress coping mechanisms at the level of gene expression in this bacterium go well beyond the induction of a relatively small number of molecular chaperones and proteases in order to ensure cellular survival at non-physiological temperatures.
- Published
- 2018
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34. Oncolytic Immunotherapy for Bladder Cancer Using Coxsackie A21 Virus.
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Annels NE, Arif M, Simpson GR, Denyer M, Moller-Levet C, Mansfield D, Butler R, Shafren D, Au G, Knowles M, Harrington K, Vile R, Melcher A, and Pandha H
- Abstract
As a clinical setting in which local live biological therapy is already well established, non-muscle invasive bladder cancer (NMIBC) presents intriguing opportunities for oncolytic virotherapy. Coxsackievirus A21 (CVA21) is a novel intercellular adhesion molecule-1 (ICAM-1)-targeted immunotherapeutic virus. This study investigated CVA21-induced cytotoxicity in a panel of human bladder cancer cell lines, revealing a range of sensitivities largely correlating with expression of the viral receptor ICAM-1. CVA21 in combination with low doses of mitomycin-C enhanced CVA21 viral replication and oncolysis by increasing surface expression levels of ICAM-1. This was further confirmed using 300-μm precision slices of NMIBC where levels of virus protein expression and induction of apoptosis were enhanced with prior exposure to mitomycin-C. Given the importance of the immunogenicity of dying cancer cells for triggering tumor-specific responses and long-term therapeutic success, the ability of CVA21 to induce immunogenic cell death was investigated. CVA21 induced immunogenic apoptosis in bladder cancer cell lines, as evidenced by expression of the immunogenic cell death (ICD) determinant calreticulin, and HMGB-1 release and the ability to reject MB49 tumors in syngeneic mice after vaccination with MB49 cells undergoing CVA21 induced ICD. Such CVA21 immunotherapy could offer a potentially less toxic, more effective option for the treatment of bladder cancer.
- Published
- 2018
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35. The prognostic significance of specific HOX gene expression patterns in ovarian cancer.
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Kelly Z, Moller-Levet C, McGrath S, Butler-Manuel S, Kavitha Madhuri T, Kierzek AM, Pandha H, Morgan R, and Michael A
- Subjects
- Adenocarcinoma drug therapy, Adenocarcinoma pathology, Animals, Apoptosis genetics, Cell Line, Tumor, Drug Resistance, Neoplasm, Female, Gene Expression Regulation, Neoplastic, Humans, Mice, Mice, Inbred BALB C, Mice, Nude, Organoplatinum Compounds pharmacology, Ovarian Neoplasms drug therapy, Ovarian Neoplasms pathology, Prognosis, Adenocarcinoma genetics, Genes, Homeobox, Ovarian Neoplasms genetics
- Abstract
HOX genes are vital for all aspects of mammalian growth and differentiation, and their dysregulated expression is related to ovarian carcinogenesis. The aim of the current study was to establish the prognostic value of HOX dysregulation as well as its role in platinum resistance. The potential to target HOX proteins through the HOX/PBX interaction was also explored in the context of platinum resistance. HOX gene expression was determined in ovarian cancer cell lines and primary EOCs by QPCR, and compared to expression in normal ovarian epithelium and fallopian tube tissue samples. Statistical analysis included one-way ANOVA and t-tests, using statistical software R and GraphPad. The analysis identified 36 of the 39 HOX genes as being overexpressed in high grade serous EOC compared to normal tissue. We detected a molecular HOX gene-signature that predicted poor outcome. Overexpression of HOXB4 and HOXB9 was identified in high grade serous cell lines after platinum resistance developed. Targeting the HOX/PBX dimer with the HXR9 peptide enhanced the cytotoxicity of cisplatin in platinum-resistant ovarian cancer. In conclusion, this study has shown the HOX genes are highly dysregulated in ovarian cancer with high expression of HOXA13, B6, C13, D1 and D13 being predictive of poor clinical outcome. Targeting the HOX/PBX dimer in platinum-resistant cancer represents a potentially new therapeutic option that should be further developed and tested in clinical trials., (© 2016 The Authors International Journal of Cancer published by John Wiley & Sons Ltd on behalf of UICC.)
- Published
- 2016
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36. The Tomato/GFP-FLP/FRT method for live imaging of mosaic adult Drosophila photoreceptor cells.
- Author
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Dourlen P, Levet C, Mejat A, Gambis A, and Mollereau B
- Subjects
- Animals, Drosophila genetics, Drosophila Proteins, Green Fluorescent Proteins biosynthesis, Green Fluorescent Proteins genetics, Microscopy, Fluorescence methods, Photoreceptor Cells, Invertebrate chemistry, Photoreceptor Cells, Invertebrate metabolism, Recombination, Genetic, Transcription Factors biosynthesis, Transcription Factors chemistry, Transcription Factors genetics, Drosophila cytology, Green Fluorescent Proteins chemistry, Photoreceptor Cells, Invertebrate cytology, Retina cytology
- Abstract
The Drosophila eye is widely used as a model for studies of development and neuronal degeneration. With the powerful mitotic recombination technique, elegant genetic screens based on clonal analysis have led to the identification of signaling pathways involved in eye development and photoreceptor (PR) differentiation at larval stages. We describe here the Tomato/GFP-FLP/FRT method, which can be used for rapid clonal analysis in the eye of living adult Drosophila. Fluorescent photoreceptor cells are imaged with the cornea neutralization technique, on retinas with mosaic clones generated by flipase-mediated recombination. This method has several major advantages over classical histological sectioning of the retina: it can be used for high-throughput screening and has proved an effective method for identifying the factors regulating PR survival and function. It can be used for kinetic analyses of PR degeneration in the same living animal over several weeks, to demonstrate the requirement for specific genes for PR survival or function in the adult fly. This method is also useful for addressing cell autonomy issues in developmental mutants, such as those in which the establishment of planar cell polarity is affected.
- Published
- 2013
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37. An in vivo hypoxia metagene identifies the novel hypoxia inducible factor target gene SLCO1B3.
- Author
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Ramachandran A, Betts G, Bhana S, Helme G, Blick C, Moller-Levet C, Saunders E, Valentine H, Pepper S, Miller CJ, Buffa F, Harris AL, and West CM
- Subjects
- Blotting, Western, Caco-2 Cells, Cell Hypoxia genetics, Cell Line, Tumor, Cell Proliferation, Cell Size, Colorectal Neoplasms genetics, Colorectal Neoplasms metabolism, Colorectal Neoplasms pathology, Crk-Associated Substrate Protein genetics, Flow Cytometry, HCT116 Cells, Head and Neck Neoplasms genetics, Head and Neck Neoplasms metabolism, Head and Neck Neoplasms pathology, Humans, Immunohistochemistry, Introns genetics, Neoplasms metabolism, Neoplasms pathology, Oligonucleotide Array Sequence Analysis, Organic Anion Transporters, Sodium-Independent metabolism, RNA Interference, RNA-Binding Proteins genetics, Response Elements genetics, Reverse Transcriptase Polymerase Chain Reaction, Solute Carrier Organic Anion Transporter Family Member 1B3, Spheroids, Cellular metabolism, Spheroids, Cellular pathology, Gene Expression Profiling, Gene Expression Regulation, Neoplastic, Neoplasms genetics, Organic Anion Transporters, Sodium-Independent genetics
- Abstract
A hypoxia-associated gene signature (metagene) was previously derived via in vivo data-mining. In this study, we aimed to investigate whether this approach could identify novel hypoxia regulated genes. From an initial list of nine genes, three were selected for further study (BCAR1, IGF2BP2 and SLCO1B3). Ten cell lines were exposed to hypoxia and interrogated for the expression of the three genes. All three genes were hypoxia inducible in at least one of the 10 cell lines with SLCO1B3 induced in seven. SLCO1B3 was studied further using chromatin immunoprecipitation and luciferase assays to investigate hypoxia inducible factor (HIF) dependent transcription. Two functional HIF response elements were identified within intron 1 of the gene. The functional importance of SLCO1B3 was studied by gene knockdown experiments followed by cell growth assays, flow cytometry and Western blotting. SLCO1B3 knockdown reduced cell size and 3-dimensional spheroid volume, which was associated with decreased activation of the mammalian target of rapamycin (mTOR) pathway. Finally, Oncomine analysis revealed that head and neck and colorectal tumours had higher levels of SLCO1B3 compared to normal tissue. Thus, the knowledge based approach for deriving gene signatures can identify novel biologically relevant genes., (Copyright © 2012. Published by Elsevier Ltd.)
- Published
- 2013
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38. Prospective technical validation and assessment of intra-tumour heterogeneity of a low density array hypoxia gene profile in head and neck squamous cell carcinoma.
- Author
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Betts GN, Eustace A, Patiar S, Valentine HR, Irlam J, Ramachandran A, Merve A, Homer JJ, Möller-Levet C, Buffa FM, Hall G, Miller CJ, Harris AL, and West CM
- Subjects
- Adult, Aged, Aged, 80 and over, Carcinoma, Squamous Cell pathology, Female, Head and Neck Neoplasms pathology, Humans, Immunohistochemistry, Male, Middle Aged, Neoplasm Staging, Real-Time Polymerase Chain Reaction, Reproducibility of Results, Reverse Transcriptase Polymerase Chain Reaction, Sensitivity and Specificity, Transcriptome, Carcinoma, Squamous Cell genetics, Cell Hypoxia genetics, Gene Expression Profiling methods, Head and Neck Neoplasms genetics
- Abstract
Background and Purpose: Tumour hypoxia is associated with a poor prognosis in head and neck squamous cell carcinoma (HNSCC), however there is no accepted method for assessing hypoxia clinically. We aimed to conduct a technical validation of a hypoxia gene expression signature using the TaqMan Low Density Array (TLDA) platform to investigate if this approach reliably identified hypoxic tumours., Materials and Methods: Tumour samples (n=201) from 80 HNSCC patients were collected prospectively from two centres. Fifty-three patients received pimonidazole prior to surgery. TaqMan Low Density Array-Hypoxia Scores (TLDA-HS) were obtained by quantitative real-time PCR (qPCR) using a 25-gene signature and customised TLDA cards. Assay performance was assessed as coefficient of variation (CoV)., Results: The assay was sensitive with linear reaction efficiencies across a 4 log(10) range of inputted cDNA (0.001-10 ng/μl). Intra- (CoV=6.9%) and inter- (CoV=2.0%) assay reproducibility were excellent. Intra-tumour heterogeneity was lower for TLDA-HS (23.2%) than for pimonidazole (67.2%) or single gene measurements of CA9 (62.2%), VEGFA (45.0%) or HIG2 (39.4%). TLDA-HS in HNSCC cell lines increased with decreasing pO(2). TLDA-HS correlated with Affymetrix U133 Plus 2.0 microarray HS (p<0.01) and positive pimonidazole scores (p=0.005)., Conclusions: Gene expression measurements of hypoxia using a 25-gene signature and TLDA cards are sensitive, reproducible and associated with lower intra-tumour heterogeneity than assaying individual genes or pimonidazole binding. The approach is suitable for further assessment of prognostic and predictive capability in clinical trial material., (Copyright © 2012 Elsevier Ltd. All rights reserved.)
- Published
- 2013
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39. ER stress inhibits neuronal death by promoting autophagy.
- Author
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Fouillet A, Levet C, Virgone A, Robin M, Dourlen P, Rieusset J, Belaidi E, Ovize M, Touret M, Nataf S, and Mollereau B
- Subjects
- Animals, Cytoprotection drug effects, Disease Models, Animal, Drosophila melanogaster metabolism, Mice, Neurons drug effects, Neuroprotective Agents pharmacology, Oxidopamine, Parkinson Disease pathology, Tunicamycin pharmacology, Autophagy drug effects, Endoplasmic Reticulum Stress drug effects, Neurons pathology
- Abstract
Endoplasmic reticulum (ER) stress has been implicated in neurodegenerative diseases but its relationship and role in disease progression remain unclear. Using genetic and pharmacological approaches, we showed that mild ER stress ("preconditioning") is neuroprotective in Drosophila and mouse models of Parkinson disease. In addition, we found that the combination of mild ER stress and apoptotic signals triggers an autophagic response both in vivo and in vitro. We showed that when autophagy is impaired, ER-mediated protection is lost. We further demonstrated that autophagy inhibits caspase activation and apoptosis. Based on our findings, we conclude that autophagy is required for the neuroprotection mediated by mild ER stress, and therefore ER preconditioning has potential therapeutic value for the treatment of neurodegenerative diseases.
- Published
- 2012
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40. ER stress protects from retinal degeneration.
- Author
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Mendes CS, Levet C, Chatelain G, Dourlen P, Fouillet A, Dichtel-Danjoy ML, Gambis A, Ryoo HD, Steller H, and Mollereau B
- Subjects
- Animals, Apoptosis drug effects, Caspases metabolism, Cell Line, DNA-Binding Proteins genetics, DNA-Binding Proteins physiology, Drosophila Proteins genetics, Drosophila Proteins physiology, Drosophila melanogaster cytology, Drosophila melanogaster drug effects, Endoplasmic Reticulum metabolism, Hydrogen Peroxide pharmacology, Membrane Proteins genetics, Membrane Proteins physiology, Molecular Chaperones genetics, Molecular Chaperones physiology, Mutation, Photoreceptor Cells cytology, Photoreceptor Cells drug effects, Photoreceptor Cells metabolism, Retina cytology, Retina drug effects, Retina metabolism, Retinal Degeneration genetics, Reverse Transcriptase Polymerase Chain Reaction, Stress, Physiological genetics, Drosophila melanogaster physiology, Endoplasmic Reticulum physiology, Retinal Degeneration metabolism, Stress, Physiological physiology
- Abstract
The unfolded protein response (UPR) is a specific cellular process that allows the cell to cope with the overload of unfolded/misfolded proteins in the endoplasmic reticulum (ER). ER stress is commonly associated with degenerative pathologies, but its role in disease progression is still a matter for debate. Here, we found that mutations in the ER-resident chaperone, neither inactivation nor afterpotential A (NinaA), lead to mild ER stress, protecting photoreceptor neurons from various death stimuli in adult Drosophila. In addition, Drosophila S2 cultured cells, when pre-exposed to mild ER stress, are protected from H(2)O(2), cycloheximide- or ultraviolet-induced cell death. We show that a specific ER-mediated signal promotes antioxidant defences and inhibits caspase-dependent cell death. We propose that an immediate consequence of the UPR not only limits the accumulation of misfolded proteins but also protects tissues from harmful exogenous stresses.
- Published
- 2009
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41. [Pelvic floor disorders four years after first delivery: a comparative study of restrictive versus systematic episiotomy].
- Author
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Fritel X, Schaal JP, Fauconnier A, Bertrand V, Levet C, and Pigné A
- Subjects
- Adult, Dyspareunia epidemiology, Dyspareunia etiology, Fecal Incontinence epidemiology, Fecal Incontinence etiology, Female, Flatulence epidemiology, Flatulence etiology, Humans, Pain epidemiology, Pain etiology, Pregnancy, Risk Factors, Urinary Incontinence epidemiology, Urinary Incontinence etiology, Episiotomy adverse effects, Episiotomy methods, Female Urogenital Diseases epidemiology, Female Urogenital Diseases etiology, Obstetric Labor Complications surgery, Pelvic Floor pathology
- Abstract
Objective: To compare two policies for episiotomy: restrictive and systematic., Patients and Methods: It is a quasi-randomised comparative study between two French university hospitals with contrasting episiotomy policies: one using it restrictively and the second routinely. Population included 774 nulliparous women delivered during 1996 of a singleton in cephalic presentation at a term of 37-41 weeks. A questionnaire was mailed four years after delivery. Sample size was calculated to allow showing a 10% difference in the prevalence of urinary incontinence with 80% power. Main outcome measures were urinary incontinence, anal incontinence, perineal pain and pain during intercourse., Results: We received 627 responses (81%), 320 from women delivered under the restrictive policy, 307 from women delivered under the routine policy. In the restrictive group, 186 (49%) deliveries included mediolateral episiotomies and in the routine group, 348 (88%). Four years after the first delivery, the groups did not differ in the prevalence of urinary incontinence (26% versus 32%), perineal pain (6% versus 8%), or pain during intercourse (18% versus 21%). Anal incontinence was less prevalent in the restrictive group (11% versus 16%). The difference was significant for flatus (8% versus 13%) but not for faecal incontinence (3% for both groups). Logistic regression confirmed that a policy of routine episiotomy was associated with a risk of anal incontinence nearly twice as high as the risk associated with a restrictive policy (OR=1.84, 95 % CI :1.05-3.22)., Discussion and Conclusion: A policy of routine episiotomy does not protect against urinary or anal incontinence four years after first delivery.
- Published
- 2008
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42. Pelvic floor disorders 4 years after first delivery: a comparative study of restrictive versus systematic episiotomy.
- Author
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Fritel X, Schaal JP, Fauconnier A, Bertrand V, Levet C, and Pigné A
- Subjects
- Adult, Dyspareunia etiology, Episiotomy methods, Fecal Incontinence etiology, Female, Flatulence etiology, Humans, Organizational Policy, Pain etiology, Pelvic Floor, Pregnancy, Risk Factors, Urinary Incontinence etiology, Episiotomy adverse effects, Female Urogenital Diseases etiology, Obstetric Labor Complications surgery
- Abstract
Objective: To compare two policies for episiotomy: restrictive and systematic., Design: Quasi-randomised comparative study., Setting: Two French university hospitals with contrasting policies for episiotomy: one using episiotomy restrictively and the second routinely., Population: Seven hundred and seventy-four nulliparous women delivered during 1996 of a singleton in cephalic presentation at a term of 37-41 weeks., Methods: A questionnaire was mailed 4 years after delivery. Sample size was calculated to allow us to show a 10% difference in the prevalence of urinary incontinence with 80% power., Main Outcome Measures: Urinary incontinence, anal incontinence, perineal pain, and pain during intercourse., Results: We received 627 responses (81%), 320 from women delivered under the restrictive policy, 307 from women delivered under the routine policy. In the restrictive group, 186 (49%) deliveries included mediolateral episiotomies and in the routine group, 348 (88%). Four years after the first delivery, there was no difference in the prevalence of urinary incontinence (26 versus 32%), perineal pain (6 versus 8%), or pain during intercourse (18 versus 21%) between the two groups. Anal incontinence was less prevalent in the restrictive group (11 versus 16%). The difference was significant for flatus (8 versus 13%) but not for faecal incontinence (3% for both groups). Logistic regression confirmed that a policy of routine episiotomy was associated with a risk of anal incontinence nearly twice as high as the risk associated with a restrictive policy (OR = 1.84, 95% CI: 1.05-3.22)., Conclusions: A policy of routine episiotomy does not protect against urinary or anal incontinence 4 years after first delivery.
- Published
- 2008
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43. Stress urinary incontinence 4 years after the first delivery: a retrospective cohort survey.
- Author
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Fritel X, Fauconnier A, Levet C, and Bénifla JL
- Subjects
- Adult, Female, France epidemiology, Humans, Medical Records, Parity, Pregnancy, Pregnancy Complications, Puerperal Disorders etiology, Retrospective Studies, Risk Factors, Surveys and Questionnaires, Urinary Incontinence, Stress etiology, Delivery, Obstetric, Puerperal Disorders epidemiology, Urinary Incontinence, Stress epidemiology
- Abstract
Background: Our aim was to estimate the prevalence of stress urinary incontinence 4 years after the first delivery and analyze its risk factors., Methods: A retrospective cohort survey was conducted in a French university hospital. The 669 primiparous women who delivered in our department in 1996 a singleton in a vertex position between 37 and 41 weeks of amenorrhea were included. A mailed questionnaire was sent 4 years after the indexed delivery. The main outcome measure was stress urinary incontinence 4 years after the first delivery., Results: Three hundred and seven women replied, 274 had moved and 88 did not respond. Four years after the first delivery, prevalence of stress urinary incontinence was 29% (89/307). According to multiple logistic regression analysis, the independent risk factors were urine leakage before the first pregnancy [odds ratio (OR) 18.7; 95% confidence interval (CI) 3.6-96.4], urine leakage during the first pregnancy (OR 2.5; 95% CI 1.3-4.8), duration of first labor > or = 8 h (OR 3.1; 95% CI 1.7-5.7), mother's age > 30 years at the first delivery (OR 2.4; 95% CI 1.4-4.2) and cesarean section at the first delivery (OR 0.3; 95% CI 0.1-0.9)., Conclusion: Our results suggest that stress urinary incontinence after pregnancy arises from a multifactorial condition. The main risk factors are: age, previous incontinence (before or during the first pregnancy), prolonged labor and vaginal delivery.
- Published
- 2004
- Full Text
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44. [Cortisone psychoses].
- Author
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Vasquez Villareal S, Escande M, and Levet C
- Subjects
- Adrenal Cortex Hormones adverse effects, Adrenocorticotropic Hormone adverse effects, Adult, Catatonia complications, Electroencephalography, Electroshock, Female, Humans, Obesity, Rheumatic Diseases drug therapy, Cortisone adverse effects, Psychoses, Substance-Induced etiology
- Published
- 1974
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