1
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Theisen ER, Selich-Anderson J, Miller KR, Tanner JM, Taslim C, Pishas KI, Sharma S, Lessnick SL. Chromatin profiling reveals relocalization of lysine-specific demethylase 1 by an oncogenic fusion protein. Epigenetics 2020; 16:405-424. [PMID: 32842875 PMCID: PMC7993145 DOI: 10.1080/15592294.2020.1805678] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Paediatric cancers commonly harbour quiet mutational landscapes and are instead characterized by single driver events such as the mutation of critical chromatin regulators, expression of oncohistones, or expression of oncogenic fusion proteins. These events ultimately promote malignancy through disruption of normal gene regulation and development. The driver protein in Ewing sarcoma, EWS/FLI, is an oncogenic fusion and transcription factor that reshapes the enhancer landscape, resulting in widespread transcriptional dysregulation. Lysine-specific demethylase 1 (LSD1) is a critical functional partner for EWS/FLI as inhibition of LSD1 reverses the transcriptional activity of EWS/FLI. However, how LSD1 participates in fusion-directed epigenomic regulation and aberrant gene activation is unknown. We now show EWS/FLI causes dynamic rearrangement of LSD1 and we uncover a role for LSD1 in gene activation through colocalization at EWS/FLI binding sites throughout the genome. LSD1 is integral to the establishment of Ewing sarcoma super-enhancers at GGAA-microsatellites, which ubiquitously overlap non-microsatellite loci bound by EWS/FLI. Together, we show that EWS/FLI induces widespread changes to LSD1 distribution in a process that impacts the enhancer landscape throughout the genome.
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Affiliation(s)
- Emily R Theisen
- Center for Childhood Cancer and Blood Diseases, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, USA
| | - Julia Selich-Anderson
- Center for Childhood Cancer and Blood Diseases, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, USA
| | - Kyle R Miller
- Center for Childhood Cancer and Blood Diseases, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, USA
| | - Jason M Tanner
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Cenny Taslim
- Center for Childhood Cancer and Blood Diseases, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, USA
| | - Kathleen I Pishas
- Center for Childhood Cancer and Blood Diseases, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, USA.,Cancer Genomics and Genetics, Peter MacCallum Cancer Centre, Melbourne, VIC, USA
| | - Sunil Sharma
- Applied Cancer Research and Drug Discovery, Translational Genomics Research Institute (Tgen), Phoenix, AX, USA
| | - Stephen L Lessnick
- Center for Childhood Cancer and Blood Diseases, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, USA.,Division of Pediatric Hematology/Oncology/Blood and Marrow Transplant, The Ohio State University, Columbus, OH, USA
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2
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Minas TZ, Surdez D, Javaheri T, Tanaka M, Howarth M, Kang HJ, Han J, Han ZY, Sax B, Kream BE, Hong SH, Çelik H, Tirode F, Tuckermann J, Toretsky JA, Kenner L, Kovar H, Lee S, Sweet-Cordero EA, Nakamura T, Moriggl R, Delattre O, Üren A. Combined experience of six independent laboratories attempting to create an Ewing sarcoma mouse model. Oncotarget 2018; 8:34141-34163. [PMID: 27191748 PMCID: PMC5470957 DOI: 10.18632/oncotarget.9388] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 05/05/2016] [Indexed: 12/17/2022] Open
Abstract
Ewing sarcoma (ES) involves a tumor-specific chromosomal translocation that produces the EWS-FLI1 protein, which is required for the growth of ES cells both in vitro and in vivo. However, an EWS-FLI1-driven transgenic mouse model is not currently available. Here, we present data from six independent laboratories seeking an alternative approach to express EWS-FLI1 in different murine tissues. We used the Runx2, Col1a2.3, Col1a3.6, Prx1, CAG, Nse, NEFL, Dermo1, P0, Sox9 and Osterix promoters to target EWS-FLI1 or Cre expression. Additional approaches included the induction of an endogenous chromosomal translocation, in utero knock-in, and the injection of Cre-expressing adenovirus to induce EWS-FLI1 expression locally in multiple lineages. Most models resulted in embryonic lethality or developmental defects. EWS-FLI1-induced apoptosis, promoter leakiness, the lack of potential cofactors, and the difficulty of expressing EWS-FLI1 in specific sites were considered the primary reasons for the failed attempts to create a transgenic mouse model of ES.
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Affiliation(s)
- Tsion Zewdu Minas
- Department of Oncology, Georgetown University Medical Center, Washington, DC, United States of America
| | - Didier Surdez
- Genetics and Biology of Cancers Unit, Institut Curie Research Center, PSL Research University, Île-de-France, Paris, France.,INSERM U830, Institut Curie Research Center, Île-de-France, Paris, France
| | | | - Miwa Tanaka
- Division of Carcinogenesis, The Cancer Institute, Japanese Foundation for Cancer Research, Tokyo, Japan
| | - Michelle Howarth
- Division of Hematology and Oncology, Department of Pediatrics, Stanford University School of Medicine, Stanford, CA, United States of America
| | - Hong-Jun Kang
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, LA, United States of America
| | - Jenny Han
- Department of Oncology, Georgetown University Medical Center, Washington, DC, United States of America
| | - Zhi-Yan Han
- Genetics and Biology of Cancers Unit, Institut Curie Research Center, PSL Research University, Île-de-France, Paris, France.,INSERM U830, Institut Curie Research Center, Île-de-France, Paris, France
| | - Barbara Sax
- Ludwig Boltzmann Institute for Cancer Research, Vienna, Austria
| | - Barbara E Kream
- Department of Medicine, and Genetics and Genome Sciences, University of Connecticut Health Science Center, Farmington, CT, United States of America
| | - Sung-Hyeok Hong
- Department of Oncology, Georgetown University Medical Center, Washington, DC, United States of America
| | - Haydar Çelik
- Department of Oncology, Georgetown University Medical Center, Washington, DC, United States of America
| | - Franck Tirode
- Genetics and Biology of Cancers Unit, Institut Curie Research Center, PSL Research University, Île-de-France, Paris, France.,INSERM U830, Institut Curie Research Center, Île-de-France, Paris, France
| | - Jan Tuckermann
- Institute of Comparative Molecular Endocrinology (CME), University of Ulm, Ulm, Germany
| | - Jeffrey A Toretsky
- Department of Oncology, Georgetown University Medical Center, Washington, DC, United States of America
| | - Lukas Kenner
- Ludwig Boltzmann Institute for Cancer Research, Vienna, Austria.,Clinical Institute of Pathology, Medical University of Vienna, Vienna, Austria.,Department of Pathology of Laboratory Animals (UPLA), University of Veterinary Medicine, Vienna, Austria
| | - Heinrich Kovar
- Department of Pediatrics, Medical University of Vienna, Vienna, Austria.,Children´s Cancer Research Institute, St. Anna Kinderkrebsforschung, Vienna, Austria
| | - Sean Lee
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, LA, United States of America
| | - E Alejandro Sweet-Cordero
- Division of Hematology and Oncology, Department of Pediatrics, Stanford University School of Medicine, Stanford, CA, United States of America
| | - Takuro Nakamura
- Division of Carcinogenesis, The Cancer Institute, Japanese Foundation for Cancer Research, Tokyo, Japan
| | - Richard Moriggl
- Ludwig Boltzmann Institute for Cancer Research, Vienna, Austria.,Institute of Animal Breeding and Genetics, University of Veterinary Medicine, Vienna, Austria.,Medical University of Vienna, Vienna, Austria
| | - Olivier Delattre
- Genetics and Biology of Cancers Unit, Institut Curie Research Center, PSL Research University, Île-de-France, Paris, France.,INSERM U830, Institut Curie Research Center, Île-de-France, Paris, France.,Unité de génétique somatique, Institut Curie, Île-de-France, Paris, France
| | - Aykut Üren
- Department of Oncology, Georgetown University Medical Center, Washington, DC, United States of America
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3
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Grünewald TGP, Bernard V, Gilardi-Hebenstreit P, Raynal V, Surdez D, Aynaud MM, Mirabeau O, Cidre-Aranaz F, Tirode F, Zaidi S, Perot G, Jonker AH, Lucchesi C, Le Deley MC, Oberlin O, Marec-Bérard P, Véron AS, Reynaud S, Lapouble E, Boeva V, Rio Frio T, Alonso J, Bhatia S, Pierron G, Cancel-Tassin G, Cussenot O, Cox DG, Morton LM, Machiela MJ, Chanock SJ, Charnay P, Delattre O. Chimeric EWSR1-FLI1 regulates the Ewing sarcoma susceptibility gene EGR2 via a GGAA microsatellite. Nat Genet 2015. [PMID: 26214589 DOI: 10.1038/ng.3363] [Citation(s) in RCA: 120] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Deciphering the ways in which somatic mutations and germline susceptibility variants cooperate to promote cancer is challenging. Ewing sarcoma is characterized by fusions between EWSR1 and members of the ETS gene family, usually EWSR1-FLI1, leading to the generation of oncogenic transcription factors that bind DNA at GGAA motifs. A recent genome-wide association study identified susceptibility variants near EGR2. Here we found that EGR2 knockdown inhibited proliferation, clonogenicity and spheroidal growth in vitro and induced regression of Ewing sarcoma xenografts. Targeted germline deep sequencing of the EGR2 locus in affected subjects and controls identified 291 Ewing-associated SNPs. At rs79965208, the A risk allele connected adjacent GGAA repeats by converting an interspaced GGAT motif into a GGAA motif, thereby increasing the number of consecutive GGAA motifs and thus the EWSR1-FLI1-dependent enhancer activity of this sequence, with epigenetic characteristics of an active regulatory element. EWSR1-FLI1 preferentially bound to the A risk allele, which increased global and allele-specific EGR2 expression. Collectively, our findings establish cooperation between a dominant oncogene and a susceptibility variant that regulates a major driver of Ewing sarcomagenesis.
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Affiliation(s)
- Thomas G P Grünewald
- Genetics and Biology of Cancers Unit, Institut Curie, PSL Research University, Paris, France.,INSERM U830, Institut Curie Research Center, Paris, France
| | - Virginie Bernard
- Institut Curie Genomics of Excellence (ICGex) Platform, Institut Curie Research Center, Paris, France
| | - Pascale Gilardi-Hebenstreit
- École Normale Supérieure (ENS), Institut de Biologie de l'ENS (IBENS), INSERM U1024, CNRS UMR8197, Paris, France
| | - Virginie Raynal
- Genetics and Biology of Cancers Unit, Institut Curie, PSL Research University, Paris, France.,INSERM U830, Institut Curie Research Center, Paris, France.,Institut Curie Genomics of Excellence (ICGex) Platform, Institut Curie Research Center, Paris, France
| | - Didier Surdez
- Genetics and Biology of Cancers Unit, Institut Curie, PSL Research University, Paris, France.,INSERM U830, Institut Curie Research Center, Paris, France
| | - Marie-Ming Aynaud
- Genetics and Biology of Cancers Unit, Institut Curie, PSL Research University, Paris, France.,INSERM U830, Institut Curie Research Center, Paris, France
| | - Olivier Mirabeau
- Genetics and Biology of Cancers Unit, Institut Curie, PSL Research University, Paris, France.,INSERM U830, Institut Curie Research Center, Paris, France
| | - Florencia Cidre-Aranaz
- Instituto de Investigación de Enfermedades Raras, Instituto de Salud Carlos III, Madrid, Spain
| | - Franck Tirode
- Genetics and Biology of Cancers Unit, Institut Curie, PSL Research University, Paris, France.,INSERM U830, Institut Curie Research Center, Paris, France
| | - Sakina Zaidi
- Genetics and Biology of Cancers Unit, Institut Curie, PSL Research University, Paris, France.,INSERM U830, Institut Curie Research Center, Paris, France
| | - Gaëlle Perot
- INSERM U916 Biology of Sarcomas, Institut Bergonié, Bordeaux, France
| | - Anneliene H Jonker
- Genetics and Biology of Cancers Unit, Institut Curie, PSL Research University, Paris, France.,INSERM U830, Institut Curie Research Center, Paris, France
| | - Carlo Lucchesi
- Genetics and Biology of Cancers Unit, Institut Curie, PSL Research University, Paris, France.,INSERM U830, Institut Curie Research Center, Paris, France
| | - Marie-Cécile Le Deley
- Département d'Epidémiologie et de Biostatistiques, Institut Gustave Roussy, Villejuif, France
| | - Odile Oberlin
- Département de Pédiatrie, Institut Gustave Roussy, Villejuif, France
| | - Perrine Marec-Bérard
- Institute for Pediatric Hematology and Oncology, Leon-Bérard Cancer Center, University of Lyon, Lyon, France
| | - Amélie S Véron
- INSERM U1052, Léon-Bérard Cancer Centre, Cancer Research Center of Lyon, Lyon, France
| | - Stephanie Reynaud
- Unité Génétique Somatique (UGS), Institut Curie Centre Hospitalier, Paris, France
| | - Eve Lapouble
- Unité Génétique Somatique (UGS), Institut Curie Centre Hospitalier, Paris, France
| | - Valentina Boeva
- INSERM U900, Bioinformatics, Biostatistics, Epidemiology and Computational Systems Biology of Cancer, Institut Curie Research Center, Paris, France.,Mines ParisTech, Fontainebleau, France
| | - Thomas Rio Frio
- Institut Curie Genomics of Excellence (ICGex) Platform, Institut Curie Research Center, Paris, France
| | - Javier Alonso
- Instituto de Investigación de Enfermedades Raras, Instituto de Salud Carlos III, Madrid, Spain
| | - Smita Bhatia
- Institute for Cancer Outcomes and Survivorship, School of Medicine, University of Alabama, Birmingham, Alabama, USA
| | - Gaëlle Pierron
- Unité Génétique Somatique (UGS), Institut Curie Centre Hospitalier, Paris, France
| | - Geraldine Cancel-Tassin
- Centre de Recherche sur les Pathologies Prostatiques (CeRePP)-Laboratory for Urology, Research Team 2, UPMC, Hôpital Tenon, Paris, France
| | - Olivier Cussenot
- Centre de Recherche sur les Pathologies Prostatiques (CeRePP)-Laboratory for Urology, Research Team 2, UPMC, Hôpital Tenon, Paris, France
| | - David G Cox
- INSERM U1052, Léon-Bérard Cancer Centre, Cancer Research Center of Lyon, Lyon, France
| | - Lindsay M Morton
- Division of Cancer Epidemiology and Genetics (DCEG), National Cancer Institute (NCI), Bethesda, Maryland, USA
| | - Mitchell J Machiela
- Division of Cancer Epidemiology and Genetics (DCEG), National Cancer Institute (NCI), Bethesda, Maryland, USA
| | - Stephen J Chanock
- Division of Cancer Epidemiology and Genetics (DCEG), National Cancer Institute (NCI), Bethesda, Maryland, USA
| | - Patrick Charnay
- École Normale Supérieure (ENS), Institut de Biologie de l'ENS (IBENS), INSERM U1024, CNRS UMR8197, Paris, France
| | - Olivier Delattre
- Genetics and Biology of Cancers Unit, Institut Curie, PSL Research University, Paris, France.,INSERM U830, Institut Curie Research Center, Paris, France.,Institut Curie Genomics of Excellence (ICGex) Platform, Institut Curie Research Center, Paris, France.,Unité Génétique Somatique (UGS), Institut Curie Centre Hospitalier, Paris, France
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4
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Gown AM, Bacchi CE. Immunohistochemistry of Small Blue Round Cell Tumors. J Histotechnol 2013. [DOI: 10.1179/his.2002.25.4.229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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5
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Abstract
Ewing sarcoma is a pediatric bone tumor characterized in 85% of cases by the fusion between EWS and FLI1 genes that results in the expression of the EWS-FLI1 aberrant transcription factor. Histologically, the Ewing tumor expresses high levels of the CD99 membrane glycoprotein. It has been recently described that CD99 expression contributes to the Ewing tumor oncogenesis by modulating growth and differentiation of tumor cells. Different studies have also shown that overexpression of EWS-FLI1 induces CD99 expression in non-Ewing cells. At the opposite, the knockdown of EWS-FLI1 expression by siRNA approaches has no significant effect on CD99 mRNA level in Ewing cells. Here, by in vivo and in vitro studies, we show that while EWS-FLI1 inhibition has only slight effects on the amount of CD99 transcript, it induces a dramatic decrease of the CD99 protein expression level, hence suggesting post-transcriptional regulations, possibly mediated by microRNAs. To further investigate this issue, we identified a set of 91 miRNAs that demonstrate EWS-FLI1 modulation, three of them being predicted to bind CD99 3' untranslated region (30'UTR). Among these, we show that miR-30a-5p has the ability to interact with the 30'UTR region of CD99 and to regulate its expression. Moreover, the re-expression of miRNA-30a-5p in Ewing cell line induces decreased cell proliferation and invasion. In this study, we therefore show that miR-30a-5p constitutes a major functional link between EWS-FLI1 and CD99, two critical biomarkers and therapeutic targets in Ewing sarcoma.
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6
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Nilsson G, Wang M, Wejde J, Kreicbergs A, Larsson O. Detection of EWS/FLI-1 by Immunostaining. An Adjunctive Tool in Diagnosis of Ewing's Sarcoma and Primitive Neuroectodermal Tumour on Cytological Samples and Paraffin-Embedded Archival Material. Sarcoma 2011; 3:25-32. [PMID: 18521261 PMCID: PMC2395406 DOI: 10.1080/13577149977839] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Purpose. Recently we showed that the 68-kDa fusion protein derived
from the EWS/FLI1 hybrid gene can be specifically detected by Western blotting using
a polyclonal antibody to the C-terminal of FLI1 on biopsy material from Ewing's
sarcoma. The aim of this study was to investigate whether this antibody also could be
used for immunocytochemistry and immunohistochemistry in diagnosis of
Ewing's sarcoma. Methods. Immunostaining on paraffin-embedded archival material,
fine-needle aspirates and tumour touch imprints from Ewing's sarcomas and primitive
neuroectodermal tumours (PNET) for detection of the fusion protein was performed.
Most cases were also analysed by Western blotting.Tumours of differential
diagnostic importance were also included. Results. Eighty per cent (12/15 cases) of the Ewing tumours exhibited a positive
immunoreactivity for the FLI1 antibody. The signal was mainly localised in the nuclei
of the tumour cells, which seems reasonable since EWS/FLI1 is a transcription factor.
The signal was found to be specific since it did not appear when the blocking peptide
was added to the antibody solution.Moreover, two other types of small-round cell tumours
(i.e. neuroblastoma and alveolar rhabdomyosarcoma) were negative as well as most
normal tissues. Discussion. Immunostaining of histological and cytological specimens
with the FLI1 antibody can be of diagnostic relevance in Ewing tumours carrying
t(11;22).The absence of immunoreactivity in non-Ewing cells is most likely due to a
low expression of the wild-type FLI1 protein.
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Affiliation(s)
- G Nilsson
- Department of Cellular and Molecular Tumour Pathology Cancer Center Karolinska Karolinska Hospital Stockholm S-17176 Sweden
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7
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Alteration of cyclin D1 transcript elongation by a mutated transcription factor up-regulates the oncogenic D1b splice isoform in cancer. Proc Natl Acad Sci U S A 2008; 105:6004-9. [PMID: 18413612 DOI: 10.1073/pnas.0710748105] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Pre-mRNA splicing and polyadenylation are tightly connected to transcription, and transcriptional stimuli and elongation dynamics can affect mRNA maturation. However, whether this regulatory mechanism has a physio/pathological impact is not known. In cancer, where splice variant expression is often deregulated, many mutated oncogenes are transcriptional regulators. In particular, the Ewing sarcoma (EwSa) oncogene, resulting from a fusion of the EWS and FLI1 genes, encodes a well characterized transcription factor. EWS-FLI1 directly stimulates transcription of the CCND1 protooncogene encoding cyclin D1a and a less abundant but more oncogenic splice isoform, D1b. We show that, although both EWS and EWS-FLI1 enhance cyclin D1 gene expression, they regulate the D1b/D1a transcript ratio in an opposite manner. Detailed analyses of RNA polymerase dynamics along the gene and of the effects of an inhibitor of elongation show that EWS-FLI1 favors D1b isoform expression by decreasing the elongation rate, whereas EWS has opposite effects. As a result, the D1b/D1a ratio is elevated in EwSa cell lines and tumors. The endogenous D1b protein is enriched in nuclei, where the oncogenic activity of cyclin D1 is known to occur, and depleting D1b in addition to D1a results in a stronger reduction of EwSa cell growth than depleting D1a only. These data show that elevated expression of a splice isoform in cancer can be due to an alteration of the transcription process by a mutated transcriptional regulator and provide evidence for a physio/pathological impact of the coupling between transcription and mRNA maturation.
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8
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Guipaud O, Guillonneau F, Labas V, Praseuth D, Rossier J, Lopez B, Bertrand P. An in vitro enzymatic assay coupled to proteomics analysis reveals a new DNA processing activity for Ewing sarcoma and TAF(II)68 proteins. Proteomics 2007; 6:5962-72. [PMID: 17106916 DOI: 10.1002/pmic.200600259] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Based on structural and functional similarities, translocated in liposarcoma/fusion (TLS/FUS) protein, Ewing sarcoma (EWS) protein and human TATA binding protein-associated factor (hTAF(II)68) have been grouped in the TLS-EWS-TAF(II)68 (TET) protein family. Translocations involving their genes lead to sarcomas. Polypyrimidine tract-binding protein-associated splicing factor (PSF), although not grouped in this family, presents structural and functional similarities with TET proteins and is involved in translocation leading to carcinoma. Beside their role in RNA metabolism, the precise cellular functions of these multifunctional proteins are not yet fully elucidated. We previously showed that both TLS/FUS and PSF display activities able to pair homologous DNA on membrane in an in vitro assay. In the present study, we address the question whether EWS and hTAF(II)68 also display pairing on membrane activities, and to a larger extent whether other proteins also exhibit such activity. We applied the pairing on membrane assay to 2-DE coupled to MS analysis for a global screening of DNA pairing on membrane activities. In addition to TLS/FUS and PSF, this test allowed us to identify EWS and hTAF(II)68, but no other proteins, indicating a feature specific to a protein family whose members share extensive structural similarities. This common activity suggests a role for TET proteins and PSF in genome plasticity control.
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Affiliation(s)
- Olivier Guipaud
- Commissariat à l'Energie Atomique, Département de Radiobiologie et Radiopathologie, Fontenay aux Roses, France
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9
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Mathieu J, Besançon F. Clinically tolerable concentrations of arsenic trioxide induce p53-independent cell death and repress NF-kappa B activation in Ewing sarcoma cells. Int J Cancer 2006; 119:1723-7. [PMID: 16646077 DOI: 10.1002/ijc.21970] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Ewing sarcoma (ES), a highly malignant pediatric tumor, is consistently associated with translocations that fuse the EWS gene with a member of the ETS family gene, most commonly FLI-1. Despite significant advances with multiagent chemotherapy, surgery and radiotherapy, about 40% of ES patients still die from the disease. It is therefore necessary to explore novel agents for possible treatment of this tumor. Here the authors investigated the sensitivity of ES cells to clinically tolerable concentrations of arsenic trioxide (As2O3), a compound known to induce differentiation and apoptosis of other types of malignant cells. The authors report that As2O3 uniformly induced death of 6 ES-derived cell lines irrespective of their p53 status. As2O3 resulted in an apoptotic phenotype which was inhibited by the broad-spectrum caspase inhibitor ZVAD-fmk. These effects correlated with prolonged c-jun N-terminal kinase activation, which is a signal for apoptosis in ES cells. As2O3 also decreased basal and cytokine-induced NF-kappa B activity. Since the authors previously demonstrated that NF-kappa B exerts an antiapoptotic action in ES cells, As2O3 treatment may also result in a sensitization of these cells to other drugs used in combination therapy. These effects, combined with its antiangiogenic action, define As2O3 as a good candidate for future protocols to improve treatments of Ewing sarcomas, irrespective of the p53 status of the tumor.
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Affiliation(s)
- Julie Mathieu
- INSERM Unité 685, IFR 105, Hopital St-Louis, 1 avenue Claude Vellefaux, Paris cedex, France
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10
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Prieur A, Tirode F, Cohen P, Delattre O. EWS/FLI-1 silencing and gene profiling of Ewing cells reveal downstream oncogenic pathways and a crucial role for repression of insulin-like growth factor binding protein 3. Mol Cell Biol 2004; 24:7275-83. [PMID: 15282325 PMCID: PMC479730 DOI: 10.1128/mcb.24.16.7275-7283.2004] [Citation(s) in RCA: 316] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Ewing tumors are characterized by abnormal transcription factors resulting from the oncogenic fusion of EWS with members of the ETS family, most commonly FLI-1. RNA interference targeted to the junction between EWS and FLI-1 sequences was used to inactivate the EWS/FLI-1 fusion gene in Ewing cells and to explore the resulting phenotype and alteration of the gene expression profile. Loss of expression of EWS/FLI-1 resulted in the complete arrest of growth and was associated with a dramatic increase in the number of apoptotic cells. Gene profiling of Ewing cells in which the EWS/FLI-1 fusion gene had been inactivated identified downstream targets which could be grouped in two major functional clusters related to extracellular matrix structure or remodeling and regulation of signal transduction pathways. Among these targets, the insulin-like growth factor binding protein 3 gene (IGFBP-3), a major regulator of insulin-like growth factor 1 (IGF-1) proliferation and survival signaling, was strongly induced upon treating Ewing cells with EWS/FLI-1-specific small interfering RNAs. We show that EWS/FLI-1 can bind the IGFBP-3 promoter in vitro and in vivo and can repress its activity. Moreover, IGFBP-3 silencing can partially rescue the apoptotic phenotype caused by EWS/FLI-1 inactivation. Finally, IGFBP-3-induced Ewing cell apoptosis relies on both IGF-1-dependent and -independent pathways. These findings therefore identify the repression of IGFBP-3 as a key event in the development of Ewing's sarcoma.
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Affiliation(s)
- Alexandre Prieur
- Laboratoire de Pathologie Moléculaire des Cancers, INSERM U509, Section de Recherche, Institut Curie, 75248 Paris, France
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11
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Young PJ, Francis JW, Lince D, Coon K, Androphy EJ, Lorson CL. The Ewing's sarcoma protein interacts with the Tudor domain of the survival motor neuron protein. ACTA ACUST UNITED AC 2003; 119:37-49. [PMID: 14597228 DOI: 10.1016/j.molbrainres.2003.08.011] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The survival motor neuron (SMN) gene is the spinal muscular atrophy (SMA) determining gene. Here we report that the SMN protein product interacts in vitro and in vivo with the arginine/glycine (RG)-rich RNA binding protein and transcription factor, Ewing's sarcoma (EWS). Recently, the SMN encoded Tudor domain (exon 3) and the YG-motifs (exon 6) have been shown to be involved in binding to RG-rich proteins. Here, we demonstrate that the Tudor domain encoded by SMN exon 3 is independently sufficient to mediate the interaction with EWS. Synthetic mutations within the Tudor domain, as well as a SMA patient-derived mutation within exon 3, reduced the levels of the SMN/EWS interaction. Carboxyl-terminal SMN mutations that prevent formation of SMN oligomers also indirectly reduced EWS binding. A role for arginine methylation has been observed in some RG-containing SMN-interacting proteins. Here we demonstrate that SMN interacts with non-methylated EWS and an EWS-derived RG-containing peptide. In contrast to previously reported results, symmetrical dimethylation of the EWS-derived RG-peptide results in a quantitative increase in the dissociation rate between SMN and the symmetrical dimethylated EWS RG-peptide. Consistent with the interaction data, endogenous and transiently expressed SMN co-localizes with endogenous EWS in a number of cultured cell lines, as well as rat primary neuron cultures. Anti-sense RNA experiments, however, demonstrate that EWS does not mediate the nuclear distribution of SMN or other Cajal body components.
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Affiliation(s)
- Philip J Young
- Department of Veterinary Pathobiology, 210 Connaway Hall, University of Missouri, Columbia, MO 65211, USA
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12
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Starck J, Cohet N, Gonnet C, Sarrazin S, Doubeikovskaia Z, Doubeikovski A, Verger A, Duterque-Coquillaud M, Morle F. Functional cross-antagonism between transcription factors FLI-1 and EKLF. Mol Cell Biol 2003; 23:1390-402. [PMID: 12556498 PMCID: PMC141137 DOI: 10.1128/mcb.23.4.1390-1402.2003] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
FLI-1 is an ETS family transcription factor which is overexpressed in Friend erythroleukemia and contributes to the blockage of differentiation of erythroleukemic cells. We show here that FLI-1 represses the transcriptional activity of the beta-globin gene promoter in MEL cells and interacts with two of its critical transactivators, GATA-1 and EKLF. Unexpectedly, FLI-1 enhances the stimulating activity of GATA-1 on a GATA-1-responsive promoter but represses that of EKLF on beta-globin and an EKLF-responsive artificial promoters. This repressive effect of FLI-1 requires the ETS DNA binding domain and its association with either the N- or C-terminal domain, which themselves interact with EKLF but not with GATA-1. Furthermore, the FLI-1 ETS domain alone behaves as an autonomous repression domain when linked to the Gal4 DNA binding domain. Taken together, these data indicate that FLI-1 represses EKLF-dependent transcription due to the repression activity of its ETS domain and its indirect recruitment to erythroid promoters by protein-protein interaction with EKLF. Reciprocally, we also show that EKLF itself represses the FLI-1-dependent megakaryocytic GPIX gene promoter, thus further suggesting that functional cross-antagonism between FLI-1 and EKLF might be involved in the control of the erythrocytic versus megakaryocytic differentiation of bipotential progenitors.
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Affiliation(s)
- Joëlle Starck
- Centre de Génétique Moléculaire et Cellulaire, CNRS UMR 5534, 69622 Villeurbanne, France
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13
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14
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Javelaud D, Poupon MF, Wietzerbin J, Besançon F. Inhibition of constitutive NF-kappa B activity suppresses tumorigenicity of Ewing sarcoma EW7 cells. Int J Cancer 2002; 98:193-8. [PMID: 11857407 DOI: 10.1002/ijc.10192] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Ewing sarcoma is 1 of the most aggressive tumors that can affect children and young adults. Despite advances in therapy, the prognosis remains poor emphasizing the need for defining new targets for treatment. We investigated a possible role of nuclear factor-kappa B (NF-kappa B) activity of Ewing sarcoma-derived EW7 cells in their tumorigenicity. In these cells, expression of a degradation-resistant form of the inhibitory factor I kappa B alpha inhibited NF-kappa B activity without affecting their in vitro proliferation rate. It causes, however, a remarkable loss of their ability to generate tumors in nude mice that correlates with both a decrease in extracellular matrix (ECM) protein secretion and an acquisition of sensitivity to murine tumor necrosis factor alpha (TNF alpha)-induced apoptosis. These data support the concept that NF-kappa B activity plays a role in the tumorigenicity of Ewing sarcoma cells, identifying NF-kappa B as a potential target for reducing Ewing tumor progression.
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Affiliation(s)
- Delphine Javelaud
- Institut National de la Santé et de la Recherche Médicale, U 365, Institut Curie, Paris, France
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15
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Llombart-Bosch A, Navarro S. Immunohistochemical detection of EWS and FLI-1 proteinss in Ewing sarcoma and primitive neuroectodermal tumors: comparative analysis with CD99 (MIC-2) expression. Appl Immunohistochem Mol Morphol 2001; 9:255-60. [PMID: 11556754 DOI: 10.1097/00129039-200109000-00010] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The molecular analysis of the t(11;22) rearrangement involving EWS/FLI-1 genes is likely to be of diagnostic value in Ewing sarcoma (ES) and primitive neuroectodermal tumors (PNET). The objective of the current study was to analyze the immunohistochemical expression of the EWS and FLI-1 proteins in a group of small round-cell tumors (SRCT) to determine their specificity and relevance in their differential diagnosis. Forty-eight cases-10 conventional ES, 4 large-cell ES, 5 PNET, 9 neuroblastomas (NB), 6 undifferentiated synovial sarcomas (SS), 5 rhabdomyosarcomas (RB), 5 non-Hodgkin lymphomas (NHL), 1 round-cell liposarcoma, and 3 mesenchymal chondrosarcomas-were analyzed. Immunocytochemistry was performed on paraffin sections after the LSAB method and antigen retrieval using ethylenediaminetetraacetic acid buffer (pH 6). Primary antibodies included FLI-1 (C-19), EWS (N-18), EWS (C-19), and CD99 (MIC-2). As expected, CD-99 expression was found in 100% of ES/PNET cases, in 2 cases of RB, 2 SS, and 1 NHL. FLI-1 protein was observed as nuclear staining in 16 cases of ES/PNET (84%) and in 4 cases of NHL, 2 NB, and 3 SS. Normal endothelial cells and lymphocytes also were positive. EWS expression (both proteins N-18 and C-19) was detected not only in 95% of ES/PNET cases but also in more than 50% of cases from the other tumoral types (4 of 9 and 7 of 9 NB, 5 of 6 and 6 of 6 SS, 3 of 5 and 5 of 5 RB, and 2 of 5 and 3 of 5 NHL, respectively). Whereas EWS expression does not appear specific for ES/PNET, analysis of FLI-1 expression together with CD-99 is a powerful marker for ES/PNET and important factors in the differential diagnosis of SRCT.
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Affiliation(s)
- A Llombart-Bosch
- Department of Pathology, Medical School, University of Valencia, Spain.
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16
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Melot T, Dauphinot L, Sévenet N, Radvanyi F, Delattre O. Characterization of a new brain-specific isoform of the EWS oncoprotein. EUROPEAN JOURNAL OF BIOCHEMISTRY 2001; 268:3483-9. [PMID: 11422378 DOI: 10.1046/j.1432-1327.2001.02251.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
EWS and related TAFII68 and TLS/FUS genes are fused with different genes encoding transcription factors in various human cancers. The products of these genes have the ability to bind RNA and have been shown to be part of splicing and transcription complexes. We show that the EWS, TAFII68 and TLS/FUS proteins are expressed to various levels in all adult murine tissues. We characterize a new isoform of EWS that is specifically expressed in the central nervous system, in both mice and humans. It is shown to be related to a splice variant which includes a new 18-bp exon, termed 4', between exon 4 and 5. The detection of this isoform in spontaneously differentiating SH-SY5Y neuroblastoma cells and in nerve growth factor-induced PC12 cells further links this isoform to neural differentiation. RT-PCR experiments indicate that the level of expression of the brain-specific EWS isoform is stable during brain development whereas that of the ubiquitous EWS isoform decreases during this period. The two isoforms show a parallel decrease in expression after birth. The 4' exon is not detected in tumour-specific EWS fusion transcripts, suggesting that its presence may impair their oncogenic properties. Interestingly, sequences of the 4' exon and flanking regions show remarkable similarities to that of the neural-specific c-src exon, suggesting common mechanisms for the alternative splicing of these exons. The phylogenetic conservation and relationship to neural differentiation strongly suggests an important functional role for this exon.
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Affiliation(s)
- T Melot
- Laboratoire de Pathologie Moléculaire des Cancers, INSERM U509, Paris, France
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17
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Dauphinot L, De Oliveira C, Melot T, Sevenet N, Thomas V, Weissman BE, Delattre O. Analysis of the expression of cell cycle regulators in Ewing cell lines: EWS-FLI-1 modulates p57KIP2and c-Myc expression. Oncogene 2001; 20:3258-65. [PMID: 11423975 DOI: 10.1038/sj.onc.1204437] [Citation(s) in RCA: 136] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2000] [Revised: 02/21/2001] [Accepted: 03/06/2001] [Indexed: 01/01/2023]
Abstract
Ewing tumour is characterized by specific chromosome translocations which fuse EWS to a subset of genes encoding ETS transcription factors, most frequently FLI-1. We report the analysis of the expression of various cell cycle regulators both in Ewing tumour derived cell lines and in different cellular models with either inducible or constitutive EWS-FLI-1 cDNA expression. In Ewing cell lines, cyclin D1, CDK4, Rb, p27KIP1 and c-Myc were consistently highly expressed whereas p57KIP2, p15INK4B and p14ARF demonstrated undetectable or low expression levels. The amount of p16INK4A, p21CIP1, p18INKAC and CDK6 was variable from one cell line to the other. The inducible expression of EWS-FLI-1 led to a strong upregulation of c-Myc and a considerable downregulation of p57KIP2. Other proteins did not show evident modification. High c-Myc and very low p57KIP2 expression levels were also observed in neuroblastoma NGP cells constitutively expressing EWS-FLI-1 as compared to parental cells. Analysis of the p57KIP2 promoter indicated that EWS-FLI-1 downregulates, possibly through an indirect mechanism, the transcription of this gene. Finally, we show that ectopic expression of p57KIP2 in Ewing cells blocks proliferation through a complete G1 arrest. These results suggest that the modulation of p57(KIP2) expression by EWS-FLI-1 is a fundamental step in Ewing tumorigenesis.
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Affiliation(s)
- L Dauphinot
- INSERM U509, Laboratoire de Pathologie Moléculaire des Cancers, Institut Curie, 26 rue d'Ulm, 75248 Paris Cedex 05, France
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18
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Javelaud D, Wietzerbin J, Delattre O, Besançon F. Induction of p21Waf1/Cip1 by TNFalpha requires NF-kappaB activity and antagonizes apoptosis in Ewing tumor cells. Oncogene 2000; 19:61-8. [PMID: 10644980 DOI: 10.1038/sj.onc.1203246] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The Ewing family of tumors is characterized by recurrent reciprocal translocations that generate chimeric proteins, either EWS - FLI-1 or EWS - ERG. These proteins are potent transcriptional activators and are responsible for maintaining the oncogenic properties of tumor cells. Since apoptosis appears to be the main mechanism whereby chemotherapy and radiation kill tumor cells, identification of events that can antagonize apoptosis in Ewing tumors is essential for improving their response to conventional therapies. Here, we report that the transcriptional factor NF-kappaB is a survival factor for Ewing tumor-derived cells. In fact, inhibition of NF-kappaB activation as a consequence of the overexpression of a degradation-resistant form of IkappaBalpha, IkappaBalpha (A32/36), sensitized these cells to TNFalpha-induced killing. Although treatment with TNFalpha did not modify the cellular expression of Bcl-2, c-IAP1, c-IAP2, p53 and EWS - FLI-1 proteins, it increased p21Waf1/Cip1 levels. This induction required NF-kappaB activation since it was not observed in the IkappaBalpha (A32/36) expressing cells. Moreover, overexpression of p21Waf1/Cip1 in these IkappaBalpha (A32/36)-expressing cells, in which NF-kappaB and consequently p21Waf1/Cip1 are no longer inducible by TNFalpha, decreased their susceptibility to TNFalpha-induced killing. Our results therefore identify p21Waf1/Cip1 as a mediator of the antiapoptotic effect of TNFalpha-induced NF-kappaB in Ewing tumor cells.
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Affiliation(s)
- D Javelaud
- INSERM U365, Institut Curie, 26 rue d'Ulm, 75005 Paris, France
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19
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Bertolotti A, Bell B, Tora L. The N-terminal domain of human TAFII68 displays transactivation and oncogenic properties. Oncogene 1999; 18:8000-10. [PMID: 10637511 DOI: 10.1038/sj.onc.1203207] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In Ewing tumor, the (11;22) chromosomal translocation produces a chimeric molecule composed of the amino-terminal domain of EWS fused to the carboxyl-terminal DNA-binding domain of FLI-1. Previously, we have identified a novel protein TAFII68, which is highly similar to EWS and another closely related protein TLS (also called FUS). We demonstrate that the N-terminus of TAFII68 efficiently stimulates transcription when fused to two different DNA binding domains and that overexpression of TAFII68-FLI-1 chimeras in NIH3T3 cells leads to oncogenic transformation. We have also investigated the molecular mechanisms which could account for the transcriptional activation and the oncogenic transformation potential of the N-termini of TAFII68 and EWS. Thus, we have tested whether the artificial recruitment of components of the preinitiation complex (PIC) or a histone acetyltransferase (HAT) could bypass the requirement for the activation domains of either EWS or TAFII68. Recruitment of individual components of the transcription machinery or the GCN5 HAT is not sufficient to promote activation from FLI-1 responsive genes either in transfection experiments or in oncogenic transformation assays. These results suggest that the TAFII68 or EWS activation domains enhance a step after PIC formation in the transcriptional activation process.
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Affiliation(s)
- A Bertolotti
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP, BP 163 - 67404 Illkirch Cedex, CU de Strasbourg, France
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20
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MESH Headings
- Adenovirus E1A Proteins/genetics
- Adenoviruses, Human/genetics
- Adenoviruses, Human/pathogenicity
- Bone Neoplasms/genetics
- Bone Neoplasms/virology
- Cell Transformation, Neoplastic/genetics
- Cell Transformation, Viral/genetics
- Chromosomes, Human, Pair 11/genetics
- Chromosomes, Human, Pair 22/genetics
- Humans
- Oncogene Proteins, Fusion/genetics
- Proto-Oncogene Protein c-fli-1
- RNA-Binding Protein EWS
- Sarcoma, Ewing/genetics
- Sarcoma, Ewing/virology
- Transcription Factors/genetics
- Translocation, Genetic
- Tumor Cells, Cultured
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Abstract
Immunohistochemistry is an extraordinarily powerful tool in the armamentarium of the diagnostic surgical pathologist. This article discusses some ways in which immunohistochemistry assists in the diagnosis of soft tissue neoplasms. Four common clinicopathologic scenarios in soft tissue pathology are presented and a practical approach to these rare neoplasms is discussed. The limitations of immunohistochemistry and possible future directions for the application of immunohistochemistry to sarcoma diagnosis are also reviewed.
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Affiliation(s)
- A L Folpe
- Department of Pathology, Emory University Hospital, Atlanta, GA 30322, USA.
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Bertolotti A, Melot T, Acker J, Vigneron M, Delattre O, Tora L. EWS, but not EWS-FLI-1, is associated with both TFIID and RNA polymerase II: interactions between two members of the TET family, EWS and hTAFII68, and subunits of TFIID and RNA polymerase II complexes. Mol Cell Biol 1998; 18:1489-97. [PMID: 9488465 PMCID: PMC108863 DOI: 10.1128/mcb.18.3.1489] [Citation(s) in RCA: 200] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The t(11;22) chromosomal translocation specifically linked to Ewing sarcoma and primitive neuroectodermal tumor results in a chimeric molecule fusing the amino-terminus-encoding region of the EWS gene to the carboxyl-terminal DNA-binding domain encoded by the FLI-1 gene. As the function of the protein encoded by the EWS gene remains unknown, we investigated the putative role of EWS in RNA polymerase II (Pol II) transcription by comparing its activity with that of its structural homolog, hTAFII68. We demonstrate that a portion of EWS is able to associate with the basal transcription factor TFIID, which is composed of the TATA-binding protein (TBP) and TBP-associated factors (TAFIIs). In vitro binding studies revealed that both EWS and hTAFII68 interact with the same TFIID subunits, suggesting that the presence of EWS and that of hTAFII68 in the same TFIID complex may be mutually exclusive. Moreover, EWS is not exclusively associated with TFIID but, similarly to hTAFII68, is also associated with the Pol II complex. The subunits of Pol II that interact with EWS and hTAFII68 have been identified, confirming the association with the polymerase. In contrast to EWS, the tumorigenic EWS-FLI-1 fusion protein is not associated with either TFIID or Pol II in Ewing cell nuclear extracts. These observations suggest that EWS and EWS-FLI-1 may play different roles in Pol II transcription.
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Affiliation(s)
- A Bertolotti
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP, Illkirch, C.U. de Strasbourg, France
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24
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7.3 anti-Fli. Hybridoma (Larchmt) 1997. [DOI: 10.1089/hyb.1997.16.494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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