151
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Abstract
Sarcomas comprise a heterogeneous group of malignancies that are derived from mesenchymal cells, which under normal circumstances lead to the development of connective tissues such as bone, muscle, fat, and cartilage. During the past decade, insight has been gained regarding the aberrancies that occur during normal development that result in mesenchymal cells transforming into sarcomas. More recently, these insights have led to the development of successful therapies that target the specific mechanisms inherent to individual sarcomas. This overview discusses some of the aberrant molecular mechanisms shared in sarcomas and reviews several sarcoma subtypes in which the most advances have been made. Finally, the ways in which these advances in basic science are translating into and redefining clinical practice are highlighted.
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Affiliation(s)
- Igor Matushansky
- Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021, USA.
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152
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Abstract
Desmoplastic small round cell tumor (DSRCT) is a poorly understood neoplasm with distinctive clinical, histologic and immunophenotypic features. It is associated with a novel, specific chromosomal abnormality, t(11;22)(p13;q12) that fuses EWS with WT1 leading to production of a chimeric protein with transcriptional regulatory activity. This chimeric transcription factor has unique DNA-binding properties and regulates expression of specific target genes. Several of these have been identified and their biological role characterized. The dysregulated expression of EWS-WT1 targets contribute to the malignant phenotype of DSRCT and provide valuable insight regarding the molecular mechanisms underlying the development and progression of this distinct translocation associated tumor.
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Affiliation(s)
- William L Gerald
- Department of Pathology, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021, USA.
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153
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Lee J, Hopcus-Niccum DJ, Mulvihill JJ, Li S. Cytogenetic and molecular cytogenetic studies of a variant of t(21;22), ins(22;21)(q12;q21q22), with a deletion of the 3′ EWSR1 gene in a patient with Ewing sarcoma. ACTA ACUST UNITED AC 2005; 159:177-80. [PMID: 15899394 DOI: 10.1016/j.cancergencyto.2004.11.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2004] [Revised: 11/04/2004] [Accepted: 11/05/2004] [Indexed: 11/24/2022]
Abstract
Ewing sarcoma is the second most common malignant bone tumor in children and young adults. Cytogenetic analysis to identify a common t(11;22)(q23;q12) or less frequently a t(21;22)(q22;q12) or t(7;22)(p22;q12) plays an important role in the confirmation of the clinical diagnosis. We report a case of a 10-year-old female who had extraskeletal Ewing sarcoma. Conventional cytogenetic analysis revealed that 11 out of 20 cells had a derivative chromosome 22, possibly due to an insertion of the long arm of the 21q21 approximately q22. This finding was confirmed by fluorescence in situ hybridization (FISH) utilizing whole chromosome paint probes specific for chromosomes 21 and 22. Hybridization utilizing LSI EWSR1, dual-color break-apart rearrangement probe unexpectedly revealed that the 3' EWSR1 gene was lost on the derivative chromosome 22. This finding suggests that the insertion of chromosome 21 is another mechanism that could lead to EWS-ERG gene fusion. To our knowledge, this is the first case report of an insertion of a segment of 21q21 approximately q22 into the long arm of 21q12 with a loss of a DNA segment around the breakpoint on the derivative chromosome 22 in Ewing sarcoma.
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Affiliation(s)
- Jiyun Lee
- Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
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154
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Siligan C, Ban J, Bachmaier R, Spahn L, Kreppel M, Schaefer KL, Poremba C, Aryee DNT, Kovar H. EWS-FLI1 target genes recovered from Ewing's sarcoma chromatin. Oncogene 2005; 24:2512-24. [PMID: 15735734 DOI: 10.1038/sj.onc.1208455] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
In all, 85% of Ewing's sarcoma family tumors (ESFT), a neoplasm of unknown histogenesis, express EWS-FLI1 transcription factor gene fusions. To characterize direct target genes avoiding artificial model systems, we cloned genomic DNA from ESFT chromatin precipitating with EWS-FLI1. We now present a comprehensive list of 99 putative transcription factor targets identified, for the first time, by a hypothesis-free approach based on physical interaction. Gene-derived chromatin fragments co-precipitating with EWS-FLI1 were nonrandomly distributed over the human genome and localized predominantly to the upstream region and the first two introns of the genes. At least 20% of putative direct EWS-FLI1 targets were neural genes. One-third of genes recovered showed a significant ESFT-specific expression pattern and were found to be altered upon RNAi-mediated knockdown of EWS-FLI1. Among them, MK-STYX, encoding a MAP kinase phosphatase-like protein, was consistently expressed in ESFT. EWS-FLI1 was found to drive MK-STYX expression by binding to a single ETS binding motif within the first gene intron. MK-STYX serves as precedence for successful recovery of direct EWS-FLI1 targets from the authentic ESFT cellular context, the most relevant system to study oncogenic mechanisms for the discovery of new therapeutic targets in this disease.
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Affiliation(s)
- Christine Siligan
- Children's Cancer Research Institute (CCRI), St Anna Kinderspital, Kinderspitalgasse 6, Vienna A1090, Austria
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155
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Hippenmeyer S, Vrieseling E, Sigrist M, Portmann T, Laengle C, Ladle DR, Arber S. A developmental switch in the response of DRG neurons to ETS transcription factor signaling. PLoS Biol 2005; 3:e159. [PMID: 15836427 PMCID: PMC1084331 DOI: 10.1371/journal.pbio.0030159] [Citation(s) in RCA: 805] [Impact Index Per Article: 42.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2004] [Accepted: 03/04/2005] [Indexed: 01/19/2023] Open
Abstract
Two ETS transcription factors of the Pea3 subfamily are induced in subpopulations of dorsal root ganglion (DRG) sensory and spinal motor neurons by target-derived factors. Their expression controls late aspects of neuronal differentiation such as target invasion and branching. Here, we show that the late onset of ETS gene expression is an essential requirement for normal sensory neuron differentiation. We provide genetic evidence in the mouse that precocious ETS expression in DRG sensory neurons perturbs axonal projections, the acquisition of terminal differentiation markers, and their dependence on neurotrophic support. Together, our findings indicate that DRG sensory neurons exhibit a temporal developmental switch that can be revealed by distinct responses to ETS transcription factor signaling at sequential steps of neuronal maturation. By expressing ETS transcription factors at different developmental stages of dorsal root ganglion development, the authors show that late onset of ETS expression is essential for normal sensory neuron differentiation
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Affiliation(s)
- Simon Hippenmeyer
- 1Biozentrum, Department of Cell BiologyUniversity of Basel, Switzerland and Friedrich Miescher Institute, BaselSwitzerland
| | - Eline Vrieseling
- 1Biozentrum, Department of Cell BiologyUniversity of Basel, Switzerland and Friedrich Miescher Institute, BaselSwitzerland
| | - Markus Sigrist
- 1Biozentrum, Department of Cell BiologyUniversity of Basel, Switzerland and Friedrich Miescher Institute, BaselSwitzerland
| | - Thomas Portmann
- 1Biozentrum, Department of Cell BiologyUniversity of Basel, Switzerland and Friedrich Miescher Institute, BaselSwitzerland
| | - Celia Laengle
- 1Biozentrum, Department of Cell BiologyUniversity of Basel, Switzerland and Friedrich Miescher Institute, BaselSwitzerland
| | - David R Ladle
- 1Biozentrum, Department of Cell BiologyUniversity of Basel, Switzerland and Friedrich Miescher Institute, BaselSwitzerland
| | - Silvia Arber
- 1Biozentrum, Department of Cell BiologyUniversity of Basel, Switzerland and Friedrich Miescher Institute, BaselSwitzerland
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156
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Amsellem V, Kryszke MH, Hervy M, Subra F, Athman R, Leh H, Brachet-Ducos C, Auclair C. The actin cytoskeleton-associated protein zyxin acts as a tumor suppressor in Ewing tumor cells. Exp Cell Res 2005; 304:443-56. [PMID: 15748890 DOI: 10.1016/j.yexcr.2004.10.035] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2004] [Revised: 09/22/2004] [Accepted: 10/30/2004] [Indexed: 01/09/2023]
Abstract
Changes in cell architecture, essentially linked to profound cytoskeleton rearrangements, are common features accompanying cell transformation. Supporting the involvement of the microfilament network in tumor cell behavior, several actin-binding proteins, including zyxin, a potential regulator of actin polymerization, may play a role in oncogenesis. In this work, we investigate the status of zyxin in Ewing tumors, a family of pediatric malignancies of bone and soft tissues, which are mainly associated with a t(11;22) chromosomal translocation encoding the EWS-FLI1 oncoprotein. We observe that EWS-FLI1-transformed murine fibroblasts, as well as human Ewing tumor-derived SK-N-MC cells, exhibit a complete disruption of their actin cytoskeleton, retaining very few stress fibers, focal adhesions and cell-to-cell contacts. We show that within these cells, zyxin is expressed at very low levels and remains diffusely distributed throughout the cytoplasm, instead of concentrating in actin-rich dynamic structures. We demonstrate that zyxin gene transfer into EWS-FLI1-transformed fibroblasts elicits reconstitution of zyxin-rich focal adhesions and intercellular junctions, dramatic reorganization of the actin cytoskeleton, decreased cell motility, inhibition of anchorage-independent growth and impairment of tumor formation in athymic mice. We observe similar phenotypic changes after zyxin gene transfer in SK-N-MC cells, suggesting that zyxin has tumor suppressor activity in Ewing tumor cells.
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Affiliation(s)
- Valérie Amsellem
- Laboratoire de Biotechnologie et Pharmacologie génétique appliquée, CNRS UMR 8113, Ecole Normale Supérieure de Cachan, 61 avenue du Président Wilson, 94230 Cachan, France.
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157
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Ganjavi H, Gee M, Narendran A, Freedman MH, Malkin D. Adenovirus-mediated p53 gene therapy in pediatric soft-tissue sarcoma cell lines: sensitization to cisplatin and doxorubicin. Cancer Gene Ther 2004; 12:397-406. [PMID: 15618970 DOI: 10.1038/sj.cgt.7700798] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Sarcomas, or tumors of connective tissue, represent roughly 20% of childhood cancers. Although the cure rate for sarcomas in general has significantly improved in the last 10 years, there continue to be subgroups that are difficult to treat. High-grade or metastatic soft-tissue sarcomas and rhabdomyosarcomas (RMS) of the extremities remain therapeutic challenges and their prognosis is often poor. The future of sarcoma therapy will likely include molecular approaches including gene/protein expression profiling and gene-based therapy. Most sarcomas harbor defects in the p53 or pRb pathways. The tumor suppressor p53 is central to regulation of cell growth and tumor suppression and restoring wild-type p53 function in pediatric sarcomas may be of therapeutic benefit. Studies with adenoviral-mediated p53 gene transfer have been conducted in many cancer types including cervical, ovarian, prostatic and head and neck tumors. Studies of this approach, however, remain limited in pediatric cancers, including sarcomas. Using three viral constructs containing cDNA for wild-type p53, mutant p53 (C135S) and lacZ, we studied the effect of adenoviral-mediated gene therapy in four pediatric sarcoma cell lines, RD and Rh4 (RMS), Rh1 (Ewing's sarcoma) and A204 (undifferentiated sarcoma). Using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay, we have shown a dose-dependent decrease in cell viability 72 h post-treatment that occurs with Ad-wtp53 but not with Ad-mutp53. Cells treated with Ad-wtp53 show upregulation of the p53 downstream targets, p21(CIP1/WAF1) and bax. Growth curves demonstrate suppression of cell growth over a period of 4 days and cells treated with Ad-wtp53 demonstrate a significant increase in sensitivity to the chemotherapeutic agents, cisplatin and doxorubicin. Our results indicate that restoration of wild-type p53 function in pediatric sarcoma cells could provide a basis for novel approaches to treatment of this disease.
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Affiliation(s)
- Hooman Ganjavi
- Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
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158
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159
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Czekalla R, Fuchs M, Stölzle A, Nerlich A, Poremba C, Schaefer KL, Weirich G, Höfler H, Schneller F, Peschel C, Siewert JR, Schepp W. Peripheral primitive neuroectodermal tumor of the stomach in a 14-year-old boy: a case report. Eur J Gastroenterol Hepatol 2004; 16:1391-400. [PMID: 15618851 DOI: 10.1097/00042737-200412000-00026] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Although PNETs are rare malignancies, they should be considered in the differential diagnosis of submucosal gastric tumours in adolescents with clinical alarm symptoms.NET was confirmed by detection of the characteristic EWS/FLI-1 fusion gene, resulting in a reciprocal translocation t(11;22)(q24;q12). Three distinct liver metastases were detected by CT, MRI, and PET. The tumour failed to respond to neoadjuvant polychemotherapy with vincristine, etoposide, doxorubicin, and ifosfamide. Subtotal gastrectomy was performed and, surprisingly, we found diffuse metastatic infiltration of the liver that had not been detected by preoperative staging. Due to the diffuse metastatic disease the young patient's prognosis has to be considered very poor. Because of the tumour's intense expression of CD117 (c-kit), the patient is now treated with the tyrosine kinase inhibitor imatinib (STI571).
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MESH Headings
- Adolescent
- Endoscopy, Gastrointestinal/methods
- Humans
- Magnetic Resonance Imaging/methods
- Male
- Neoplasm Staging
- Neuroectodermal Tumors, Primitive, Peripheral/diagnosis
- Neuroectodermal Tumors, Primitive, Peripheral/pathology
- Neuroectodermal Tumors, Primitive, Peripheral/secondary
- Neuroectodermal Tumors, Primitive, Peripheral/therapy
- Positron-Emission Tomography/methods
- Stomach Neoplasms/diagnosis
- Stomach Neoplasms/pathology
- Stomach Neoplasms/therapy
- Tomography, X-Ray Computed/methods
- Treatment Outcome
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Affiliation(s)
- Ralph Czekalla
- Second Department of Medicine, Bogenhausen Academic Teaching Hospital, Munich, Germany
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160
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Kirmizis A, Farnham PJ. Genomic approaches that aid in the identification of transcription factor target genes. Exp Biol Med (Maywood) 2004; 229:705-21. [PMID: 15337825 DOI: 10.1177/153537020422900803] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
It is well-established that deregulation of the transcriptional activity of many different genes has been causatively linked to human diseases. In cancer, altered patterns of gene expression are often the result of the inappropriate expression of a specific transcriptional activator or repressor. Functional studies of cancer-specific transcription factors have relied upon the study of candidate target genes. More recently, gene expression profiling using DNA microarrays that contain tens of thousands of cDNAs corresponding to human mRNAs has allowed for a large-scale identification of genes that respond to increased or decreased levels of a particular transcription factor. However, such experiments do not distinguish direct versus indirect target genes. Coupling chromatin immunoprecipitation to micro-arrays that contain genomic regions (ChIP-chip) has provided investigators with the ability to identify, in a high-throughput manner, promoters directly bound by specific transcription factors. Clearly, knowledge gained from both types of arrays provides complementary information, allowing greater confidence that a transcription factor regulates a particular gene. In this review, we focus on Polycomb group (PcG) complexes as an example of transcriptional regulators that are implicated in various cellular processes but about which very little is known concerning their target gene specificity. We provide examples of how both expression arrays and ChIP-chip microarray-based assays can be used to identify target genes of a particular PcG complex and suggest improvements in the application of array technology for faster and more comprehensive identification of directly regulated target genes.
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Affiliation(s)
- Antonis Kirmizis
- McArdle Laboratory for Cancer Research, University of Wisconsin Medical School, Madison 533706, USA
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161
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Filion C, Labelle Y. The oncogenic fusion protein EWS/NOR-1 induces transformation of CFK2 chondrogenic cells. Exp Cell Res 2004; 297:585-92. [PMID: 15212958 DOI: 10.1016/j.yexcr.2004.03.040] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2003] [Revised: 02/19/2004] [Indexed: 01/04/2023]
Abstract
The EWS/NOR-1 fusion protein is encoded by the t(9;22) chromosomal translocation found in approximately 75% of extraskeletal myxoid chondrosarcoma (EMC) tumors. The lack of cellular models in which the oncogenic properties of this fusion protein are expressed has seriously hampered the study of its role in the development of EMC. To generate such a cellular model, we have used the chondrogenic cell line CFK2. We show in this study that although stable expression of EWS/NOR-1 does not alter the population doubling time and the cell cycle distribution of CFK2 cells in subconfluent cultures, it induces their transformation as measured by growth beyond confluency and anchorage-independent growth in soft agarose medium. Glycosaminoglycan accumulation in CFK2(EWS/NOR-1) cell lines indicate that the fusion protein does not appear to interfere with the ability of CFK2 cells to differentiate into chondrocyte-like cells in vitro. These results support the hypothesis that the role of EWS/NOR-1 in EMC may be to disrupt the proliferation properties of cells involved in chondrogenesis.
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MESH Headings
- Amino Acid Sequence
- Animals
- Blotting, Western
- Bone Neoplasms/genetics
- Bone Neoplasms/metabolism
- Cell Differentiation
- Cell Line
- Cell Transformation, Neoplastic
- Chondrocytes/cytology
- Chromosomes, Human, Pair 22
- Chromosomes, Human, Pair 9
- DNA-Binding Proteins/chemistry
- DNA-Binding Proteins/genetics
- DNA-Binding Proteins/metabolism
- Glycosaminoglycans/biosynthesis
- Humans
- Nerve Tissue Proteins/chemistry
- Nerve Tissue Proteins/genetics
- Nerve Tissue Proteins/metabolism
- Oncogene Proteins, Fusion/metabolism
- Protein Structure, Tertiary
- Rats
- Receptors, Steroid
- Receptors, Thyroid Hormone
- Reverse Transcriptase Polymerase Chain Reaction
- Sarcoma, Ewing/chemistry
- Sarcoma, Ewing/genetics
- Sarcoma, Ewing/metabolism
- Translocation, Genetic
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Affiliation(s)
- Christine Filion
- Human and Molecular Genetic Research Unit, Pavillon Saint-François d'Assise, CHUQ, Quebec, Qc, Canada G1L 3L5
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162
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Abadie A, Besançon F, Wietzerbin J. Type I interferon and TNFalpha cooperate with type II interferon for TRAIL induction and triggering of apoptosis in SK-N-MC EWING tumor cells. Oncogene 2004; 23:4911-20. [PMID: 15077162 DOI: 10.1038/sj.onc.1207614] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Ewing's sarcoma is the second most common human bone tumor in childhood. Here, we investigated the sensitivity of the Ewing tumor cell line, SK-N-MC, to the apoptotic effect of type I (IFNalpha) and type II (IFNgamma) interferons and TNFalpha. We demonstrate that although IFNalpha and TNFalpha alone are unable to induce cell death, they act in synergy with IFNgamma to induce SK-N-MC cell apoptosis. The synergistic induction of apoptosis correlated with the synergistic induction of TNFalpha-related apoptosis-inducing ligand (TRAIL) mRNA and TRAIL protein synthesis as well as of TRAIL secretion. Preparations of inducer-free supernatants from SK-N-MC cells stimulated with combinations of cytokines were shown to be cytotoxic for untreated SK-N-MC cells. This cytotoxicity was partially inhibited by addition of TRAILR2/Fc fusion protein, indicating that the secreted TRAIL mediates, at least in part, the apoptotic effect displayed by the supernatants of stimulated SK-N-MC cells. We have shown that the presence of IFNgamma is required to allow the sustained expression of IRF1 in SK-N-MC cells stimulated by addition of IFNalpha or TNFalpha suggesting that IRF1 plays a role in the synergistic induction of apoptosis by combinations of cytokines. Furthermore, we have shown that inhibition of NF-kappaB activation contributes to the IFNgamma-mediated sensitization to the apoptotic effect of TNFalpha. To our knowledge, this is the first report showing that interferon/cytokine combinations are able to induce TRAIL gene expression and TRAIL protein synthesis and secretion in Ewing sarcoma-derived cells. We believe that the observations reported here might contribute to the development of alternative new approaches to the treatment of Ewing tumors resistant to conventional therapy.
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Affiliation(s)
- Annie Abadie
- INSERM U365 Institut Curie, Section Recherche, 26, rue D'Ulm, 75 248, Paris Cedex 05, France
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163
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Chansky HA, Barahmand-Pour F, Mei Q, Kahn-Farooqi W, Zielinska-Kwiatkowska A, Blackburn M, Chansky K, Conrad EU, Bruckner JD, Greenlee TK, Yang L. Targeting of EWS/FLI-1 by RNA interference attenuates the tumor phenotype of Ewing's sarcoma cells in vitro. J Orthop Res 2004; 22:910-7. [PMID: 15183454 DOI: 10.1016/j.orthres.2003.12.008] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2003] [Accepted: 12/03/2003] [Indexed: 02/04/2023]
Abstract
The defining cytogenetic abnormality of Ewing's sarcoma is the presence of a balanced t(11;22) translocation expressing the EWS/FLI-1 chimeric fusion protein. The effect of EWS/FLI-1 appears to be dominant negative since over-expression of EWS does not overcome the sarcoma phenotype. Previous studies have shown that EWS/FLI-1 as well as related sarcoma fusion proteins are necessary and sufficient to induce transformation both in vitro and in vivo. In this study we report that synthetic small interfering RNA (siRNA) specifically suppresses EWS/FLI-1 fusion gene expression in SK-ES Ewing's sarcoma cells. Knockdown of the EWS/FLI-1 fusion protein is correlated with decreased cell proliferation and increased apoptosis. We demonstrate that Ewing's sarcoma tumors as well as Ewing's sarcoma cell lines predominantly express the CXCR4 chemokine receptor. Using an in vitro invasion assay, the SDF-1 ligand of CXCR4 was shown to be a potent stimulus of invasion by SK-ES cells. Knockdown of EWS/FLI-1 by RNA interference abrogates the invasiveness of SK-ES cells. These experiments suggest that targeted silencing of the EWS/FLI-1 fusion gene by siRNA represents a promising strategy to study the loss of EWS/FLI-1 protein in Ewing's sarcoma cells of otherwise identical genetic background.
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Affiliation(s)
- Howard A Chansky
- Department of Orthopedics and Sports Medicine, School of Medicine, University of Washington, 1660 S. Columbian Way, ORT112, Seattle, WA 98108, USA.
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164
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Thomas GR, Faulkes DJ, Gascoyne D, Latchman DS. EWS differentially activates transcription of the Brn-3a long and short isoform mRNAs from distinct promoters. Biochem Biophys Res Commun 2004; 318:1045-51. [PMID: 15147979 DOI: 10.1016/j.bbrc.2004.04.134] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2004] [Indexed: 11/17/2022]
Abstract
Brn-3a long and short isoforms are known to be encoded by two distinct mRNA transcripts derived from a single gene. Here we report that transcription of the two isoforms is differentially regulated. The short isoform has its own promoter, though many elements in the 5' regulatory region are shared. The protein product of the EWS gene, translocations of which are associated with the Ewing's sarcoma family of tumours, is known to interact with Brn-3a via a direct protein-protein interaction. Here we show that EWS also regulates Brn-3a expression in an isoform-specific manner. The implications of these results are discussed in terms of the functional role of EWS and the distinct functional activities of the two isoforms of Brn-3a.
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Affiliation(s)
- G R Thomas
- Medical Molecular Biology Unit, Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UK
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165
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Lee HJ, Kim S, Pelletier J, Kim J. Stimulation of hTAFII68 (NTD)-mediated transactivation by v-Src. FEBS Lett 2004; 564:188-98. [PMID: 15094065 DOI: 10.1016/s0014-5793(04)00314-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2004] [Revised: 03/05/2004] [Accepted: 03/11/2004] [Indexed: 12/17/2022]
Abstract
The three genes hTAF(II)68, EWS, and TLS (called the TET family) encode related RNA binding proteins containing an RNA recognition motif and three glycine-, arginine-, and proline-rich regions in the C-terminus and a degenerated repeat containing the consensus sequence Ser-Tyr-Gly-Gln-Ser in the N-terminus. In many human cancers, the N-terminal portion of hTAF(II)68, EWS, or TLS is fused to the DNA binding domain of one of several transcription factors including Fli-1, ERG, ETV1, E1AF, WT1, ATF-1, CHOP, or TEC. We have recognized the presence of several potential tyrosine phosphorylation sites within the amino-terminal domain of hTAF(II)68 and have investigated the potential effects of cytoplasmic signaling on hTAF(II)68 function. Herein, we find that hTAF(II)68 is phosphorylated on tyrosine residue(s) by ectopic expression of v-Src protein tyrosine kinase in vitro and in vivo. The hTAF(II)68 protein can associated with the SH3 domains of several cell signaling proteins, including v-Src protein tyrosine kinase. We also document that full-length v-Src can stimulate hTAF(II)68-mediated transcriptional activation, whereas deletion mutants of v-Src are unable to exert this effect. In addition, cellular Src activity appears important for hTAF(II)68 function since hTAF(II)68-mediated transactivation is reduced in a dose-dependent fashion by ectopic overexpression of a dominant-negative mutant of Src. Taken together, our results suggest that the biological activities of hTAF(II)68 are linked to the cytoplasmic Src signal transduction pathway.
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Affiliation(s)
- Hye Jin Lee
- Laboratory of Molecular and Cellular Biology, Department of Life Science, Sogang University, Seoul 121-743, South Korea
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166
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Maksimenko A, Lambert G, Bertrand JR, Fattal E, Couvreur P, Malvy C. Therapeutic potentialities of EWS-Fli-1 mRNA-targeted vectorized antisense oligonucleotides. Ann N Y Acad Sci 2004; 1002:72-7. [PMID: 14751824 DOI: 10.1196/annals.1281.017] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We have used structured antisense oligonucleotides (AON), which are protected against extra and intracellular degradation by their internal structure. We have shown that if correctly designed this structure does not prevent them from hybridizing to the mRNA target. This concept allows reducing the number of thioate groups in the oligonucleotide and therefore the potential toxicity. Junction oncogenes are found in cancers such as certain leukemias, Ewing sarcoma, and thyroid papillary carcinomas. Ewing sarcoma is a cancer of children and young adults with bone metastasis. It is caused by a chromosomic translocation t(11;22) (q24;q12) creating a fusion gene between the genes EWS and Fli-1 giving rise to a chimeric protein which is an unnatural transcription factor. Immortalized NIH/3T3 cells transfected by the EWS-Fli-1 cDNA under the control of the LTR retroviral promoter--which do not undergo apoptosis and which became tumoral--were used for this study. As a model of Ewing sarcoma in nude mice, we have used permanently expressing human EWS-Fli-1 cells grafted to nude mice. The nanospheres or nanocapsules have been used to deliver two different AON: a phosphorothioate, and a structured chimeric AON, both targeted toward the junction area of EWS-Fli-1. Both types of AON-loaded nanoparticles inhibited the growth of the xenografted tumor after intratumoral injections into nude mice, whereas similar nanoparticles with control oligonucleotides had no effect. With AON in nanospheres, we have shown after 24 hours that the mRNA of EWS-Fli-1 was specifically down-regulated, confirming the antisense activity of the targeted AON.
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Affiliation(s)
- A Maksimenko
- BioAlliance Pharma, 59, Boulevard du Général Martial Valin, 75015 Paris
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167
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Abstract
EWS/FLI and other EWS/ets chimeric transcription factors play a central role in the biology of the Ewing family tumors. As with many oncogenes, EWS/FLI biologic activity can be demonstrated in a limited range of cellular contexts. To investigate the causes of this restriction, we demonstrate that two immortalized fibroblast lines resistant to EWS/FLI transformation, Rat1 and Yal7, express stable levels of EWS/FLI protein. Despite their resistance to EWS/FLI, Rat1 and Yal7 can be transformed by the potent EWS/FLI downstream mediator PDGF-C. In contrast to NIH3T3, the EWS/FLI resistant lines show no upregulation of PDGF-C in response to EWS/FLI, demonstrating differential EWS/FLI function in different cellular backgrounds. This phenomenon of differential function can also be demonstrated for several other NIH3T3 targets of EWS/FLI. Despite the correlation between anchorage-independent growth and PDGF-C induction, PDGF-C does not fully reproduce all aspects of the EWS/FLI phenotype in NIH3T3 cells. These results further point to the importance of PDGF-C in mediating EWS/FLI in vitro transformation and suggest caution in assuming that a transcription factor will produce identical effects in different cellular backgrounds.
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MESH Headings
- Animals
- Blotting, Northern
- Blotting, Western
- Cell Transformation, Neoplastic
- Fibroblasts/metabolism
- Gene Expression Regulation, Neoplastic
- Humans
- Lymphokines
- Mice
- Mice, SCID
- Neoplasms, Experimental/metabolism
- Neoplasms, Experimental/pathology
- Oncogene Proteins, Fusion/physiology
- Phenotype
- Platelet-Derived Growth Factor/genetics
- Platelet-Derived Growth Factor/metabolism
- Proto-Oncogene Protein c-fli-1
- RNA-Binding Protein EWS
- Sarcoma, Ewing/genetics
- Sarcoma, Ewing/metabolism
- Transcription Factors/physiology
- Up-Regulation
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Affiliation(s)
- Jeffrey P Zwerner
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35294-1150, USA
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168
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Vernell R, Helin K, Müller H. Identification of target genes of the p16INK4A-pRB-E2F pathway. J Biol Chem 2003; 278:46124-37. [PMID: 12923195 DOI: 10.1074/jbc.m304930200] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Deregulation of the retinoblastoma protein (pRB) pathway is a hallmark of human cancer. The core members of this pathway include the tumor suppressor protein, pRB, which through binding to a number of cellular proteins, most notably members of the E2F transcription factor family, regulates progression through the cell division cycle. With the aim of identifying transcriptional changes provoked by deregulation of the pRB pathway, we have used cell lines that conditionally express a constitutively active phosphorylation site mutant of pRB (pRBDeltaCDK) or p16INK4A (p16). The expression of pRBDeltaCDK and p16 resulted in significant repression and activation of a large number of genes as measured by high density oligonucleotide array analysis. Transcriptional changes were found in genes that are essential for DNA replication and cell proliferation. In agreement with previous results, we found a high degree of overlap between genes regulated by p16 and pRB. Data we have obtained previously for E2F family members showed that 74 of the genes repressed by pRB and p16 were induced by the E2Fs and 23 genes that were induced by pRB and p16 were repressed by the E2Fs. Thus, we have identified 97 genes as physiological targets of the pRB pathway, and the further characterization of these genes should provide insights into how this pathway controls proliferation. We show that Gibbs sampling detects enrichment of several sequence motifs, including E2F consensus binding sites, in the upstream regions of these genes and use this enrichment in an in silico filtering process to refine microarray derived gene lists.
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Affiliation(s)
- Richard Vernell
- Department of Experimental Oncology, European Institute of Oncology, 20141 Milan, Italy
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169
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Fuchs B, Inwards CY, Janknecht R. Upregulation of the matrix metalloproteinase-1 gene by the Ewing's sarcoma associated EWS-ER81 and EWS-Fli-1 oncoproteins, c-Jun and p300. FEBS Lett 2003; 553:104-8. [PMID: 14550555 DOI: 10.1016/s0014-5793(03)00984-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The mechanisms of action of Ewing's sarcoma (EWS) associated EWS-ETS oncoproteins have largely remained unresolved. Here, we analyzed how two EWS-ETS proteins, EWS-ER81 and EWS-Fli-1, in vitro activate the matrix metalloproteinase (MMP)-1 promoter that is upregulated in a subset of EWSs. EWS-ER81 and EWS-Fli-1 interact with and thereby activate the MMP-1 promoter, which is potentiated by the cofactor p300 and the proto-oncoprotein c-Jun. Further, EWS-ER81 binds to c-Jun in vitro and in vivo. The interaction between c-Jun, p300 and EWS-ER81 or EWS-Fli-1 may also be relevant to the regulation of other yet-to-be-identified genes that are responsible for EWS formation.
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Affiliation(s)
- Bruno Fuchs
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA
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170
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Moritake H, Sugimoto T, Kuroda H, Hidaka F, Takahashi Y, Tsuneyoshi M, Yoshida MA, Cui Q, Akiyoshi K, Izumi T, Nunoi H. Newly established Askin tumor cell line and overexpression of focal adhesion kinase in Ewing sarcoma family of tumors cell lines. ACTA ACUST UNITED AC 2003; 146:102-9. [PMID: 14553943 DOI: 10.1016/s0165-4608(03)00129-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Askin tumor is a malignant small round cell tumor that originates from the thoracopulmonary region and is a member of Ewing sarcoma family of tumors (ESFT). Only a few Askin tumor cell lines have been established. An Askin tumor cell line, designated MP-ASKIN-SA, was established from the left thoracic tumor of a 13-year-old Japanese boy. ESFT is known to have a high rate of distant metastases at diagnosis. The genes controlling the spread of ESFT cells, however, have not been elucidated. G-banding chromosome analysis revealed that the MP-ASKIN-SA cell line has complex chromosomal abnormalities including trisomy 8. The EWS/FLI1 chimeric transcript and c-myc overexpression were revealed by the reverse transcriptase-polymerase chain reaction and Northern blot analysis. Furthermore, we investigated the expression of the focal adhesion kinase (FAK) gene in the ESFT cell lines using Northern blot analysis. In addition to the MP-ASKIN-SA cell line, six Ewing sarcoma cell lines, one peripheral nerve sheath tumor cell line, and two Askin tumor cell lines were analyzed. All ESFT cell lines, including MP-ASKIN-SA, expressed five- to twenty-eight-fold-increased values of FAK, as compared with fibroblasts obtained from the bone marrow of a healthy volunteer. These results raise the possibility that the overexpression of c-myc and FAK are involved in the poor prognosis of ESFT.
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Affiliation(s)
- Hiroshi Moritake
- Department of Pediatrics, Miyazaki Medical College, Kiyotake, Miyazaki, Japan.
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171
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Lacorazza HD, Nimer SD. The emerging role of the myeloid Elf-1 like transcription factorin hematopoiesis. Blood Cells Mol Dis 2003; 31:342-50. [PMID: 14636650 DOI: 10.1016/s1079-9796(03)00162-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
MEF (myeloid Elf-1 like factor) is a member of the ETS family of transcription factors (TF) with transcriptional activating properties. ETS proteins have been implicated in widely divergent physiological and pathological processes (such as development and oncogenesis). MEF is expressed in non-hematopoietic and hematopoietic (lymphoid and myeloid) tissues, and after generating MEF-deficient mice by homologous recombination, we have studied its role in lymphopoiesis (Immunity 17 (2002), 437). MEF plays a critical role in NK and NK-T cell development and the constitutive expression of perforin by NK cells. MEF interacts with other TFs such as AML1 (Runx1) and with the cyclin A/cdk2 kinase complex. In this review, we discuss the biology of MEF in the context of the other members of this family of transcriptional regulators.
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Affiliation(s)
- H Daniel Lacorazza
- Laboratory of Molecular Aspects of Hematopoiesis, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021, USA.
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172
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Gostout BS, Lindor NM, DiMarco CS, Peethambaram PP, Clayton AC. Pelvic primitive neuroectodermal tumor associated with a cluster of small round cell tumors: case report and review of current literature. Gynecol Oncol 2003; 91:247-53. [PMID: 14529689 DOI: 10.1016/s0090-8258(03)00416-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
BACKGROUND Peripheral primitive neuroectodermal tumor (pPNET) is aggressive and rare, comprising 1% of soft tissue sarcomas. Involvement of the reproductive tract is unusual. CASE A 35-year-old woman had a pelvic mass and omental cake. Frozen-section examination at laparotomy revealed small round cell tumor confirmed as pPNET. Chemotherapy with vincristine, doxorubicin, and cyclophosphamide alternating with ifosfamide and etoposide with mesna yielded complete response. The patient's mother died of a similar tumor at age 52 years, and the patient's husband had adult Ewing sarcoma, constituting an unusual cluster of related tumors. CONCLUSIONS Genetic recombination resulting in a chimeric transcript of the Ewing sarcoma gene and the Friend leukemia virus integration site is characteristic of these tumors. Surgical resection and multiagent chemotherapy may enhance survival.
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Affiliation(s)
- Bobbie S Gostout
- Section of Gynecologic Surgery, Mayo Clinic, Rochester, MN 55905, USA
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173
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Segal NH, Pavlidis P, Antonescu CR, Maki RG, Noble WS, DeSantis D, Woodruff JM, Lewis JJ, Brennan MF, Houghton AN, Cordon-Cardo C. Classification and subtype prediction of adult soft tissue sarcoma by functional genomics. THE AMERICAN JOURNAL OF PATHOLOGY 2003; 163:691-700. [PMID: 12875988 PMCID: PMC1868218 DOI: 10.1016/s0002-9440(10)63696-6] [Citation(s) in RCA: 154] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Adult soft tissue sarcomas are a heterogeneous group of tumors, including well-described subtypes by histological and genotypic criteria, and pleomorphic tumors typically characterized by non-recurrent genetic aberrations and karyotypic heterogeneity. The latter pose a diagnostic challenge, even to experienced pathologists. We proposed that gene expression profiling in soft tissue sarcoma would identify a genomic-based classification scheme that is useful in diagnosis. RNA samples from 51 pathologically confirmed cases, representing nine different histological subtypes of adult soft tissue sarcoma, were examined using the Affymetrix U95A GeneChip. Statistical tests were performed on experimental groups identified by cluster analysis, to find discriminating genes that could subsequently be applied in a support vector machine algorithm. Synovial sarcomas, round-cell/myxoid liposarcomas, clear-cell sarcomas and gastrointestinal stromal tumors displayed remarkably distinct and homogenous gene expression profiles. Pleomorphic tumors were heterogeneous. Notably, a subset of malignant fibrous histiocytomas, a controversialhistological subtype, was identified as a distinct genomic group. The support vector machine algorithm supported a genomic basis for diagnosis, with both high sensitivity and specificity. In conclusion, we showed gene expression profiling to be useful in classification and diagnosis, providing insights into pathogenesis and pointing to potential new therapeutic targets of soft tissue sarcoma.
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Affiliation(s)
- Neil H Segal
- Swim Across America Laboratory, Department of Surgery, Memorial-Sloan Kettering Cancer Center, New York and Columbia Genome Center, Columbia University, New York, New York 10021, USA.
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174
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Nakatani F, Tanaka K, Sakimura R, Matsumoto Y, Matsunobu T, Li X, Hanada M, Okada T, Iwamoto Y. Identification of p21WAF1/CIP1 as a direct target of EWS-Fli1 oncogenic fusion protein. J Biol Chem 2003; 278:15105-15. [PMID: 12560328 DOI: 10.1074/jbc.m211470200] [Citation(s) in RCA: 114] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Translocation t(11;22) is a karyotypic abnormality detected in over 90% of Ewing's family tumors. This translocation results in the EWS-Fli1 fusion gene, which has been shown to be a potent, single-step transforming gene. We reported previously that suppression of the EWS-Fli1 fusion protein altered the expression of G(1) regulatory cyclins and cyclin-dependent kinase inhibitors both at mRNA and protein levels, resulting in G(1) growth arrest in Ewing's family tumor cell lines. These data suggest that the G(1) regulatory molecules may be targets of the EWS-Fli1 fusion protein, which functions as an aberrant transcription factor. By using electrophoretic mobility shift assays, we show here the direct association of EWS-Fli1 fusion protein with ETS consensus sequences, which are in the promoter of the p21(WAF1/CIP1) gene. Reporter gene assays revealed that the activity of the p21(WAF1/CIP1) promoter is negatively regulated by EWS-Fli1 fusion protein through at least two ETS-binding sites in the promoter. EWS-Fli1 interacted with p300 cotransactivator and suppressed its histone acetyltransferase activity, which may explain the down-regulation of p21(WAF1/CIP1) by EWS-Fli1. In the presence of a histone deacetylase inhibitor, the histone acetyltransferase activity of the Ewing's family tumor cell was recovered resulting in the induction of p21, and the cell growth was dramatically inhibited. These results demonstrated that p21(WAF1/CIP1) might be one of the direct targets of EWS-Fli1, and that p21(WAF1/CIP1) could serve as a target for a molecularly based therapy for Ewing's family tumors.
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Affiliation(s)
- Fumihiko Nakatani
- Department of Orthopedic Surgery, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
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175
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Watanabe G, Nishimori H, Irifune H, Sasaki Y, Ishida S, Zembutsu H, Tanaka T, Kawaguchi S, Wada T, Hata JI, Kusakabe M, Yoshida K, Nakamura Y, Tokino T. Induction of tenascin-C by tumor-specific EWS-ETS fusion genes. Genes Chromosomes Cancer 2003; 36:224-32. [PMID: 12557222 DOI: 10.1002/gcc.10153] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Ewing sarcoma (ES) and peripheral primitive neuroectodermal tumors (PNETs) are associated with a chromosomal translocation resulting in a fusion of the amino-terminus of EWS with the DNA-binding domain of an ETS transcription factor (most commonly FLI1 or ERG). Although previous reports suggested that these chimera proteins would act as aberrant transcription factors, their downstream targets have not been fully elucidated. To identify downstream targets of these EWS-ETS fusion proteins, we introduced EWS-ETS fusion constructs into a human fibrosarcoma cell line, HT-1080, by retroviral transduction. Here we report that Tenascin-C (TNC) is induced to a significantly higher level in cells expressing EWS-ETSs than in cells expressing normal ETSs. Furthermore, through use of an antisense cDNA expression vector we show that expression of endogenous TNC mRNA and protein were reduced coordinately with attenuation of EWS-FLI1 fusion protein expression. A chromatin immunoprecipitation assay showed direct interaction between the TNC promoter and the EWS-FLI1 fusion protein in vivo. In addition, a luciferase reporter assay revealed that EWS-ETSs upregulated the TNC gene through four ETS binding sites in the TNC promoter. High levels of TNC expression were observed in a subset of ES cell lines (3 of 6) and primary tumors (4 of 6). Together with previous studies showing that TNC expression is involved in the invasive and malignant phenotype of several tumor types, our data suggest that the oncogenic effect of EWS-ETS may be mediated in part by upregulating of TNC expression.
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MESH Headings
- DNA, Antisense/pharmacology
- DNA, Complementary/pharmacology
- Down-Regulation/drug effects
- Fibrosarcoma/genetics
- Fibrosarcoma/metabolism
- Fibrosarcoma/pathology
- Gene Expression Profiling
- Gene Expression Regulation, Neoplastic
- Genetic Vectors/genetics
- Genetic Vectors/metabolism
- Genetic Vectors/physiology
- Humans
- Oligonucleotide Array Sequence Analysis
- Oncogene Proteins, Fusion/genetics
- Oncogene Proteins, Fusion/immunology
- Oncogene Proteins, Fusion/metabolism
- Oncogene Proteins, Fusion/physiology
- Promoter Regions, Genetic/genetics
- Promoter Regions, Genetic/immunology
- Proto-Oncogene Protein c-fli-1
- Proto-Oncogene Proteins/genetics
- Proto-Oncogene Proteins/metabolism
- Proto-Oncogene Proteins/physiology
- Proto-Oncogene Proteins c-ets
- RNA, Messenger/biosynthesis
- RNA-Binding Protein EWS/genetics
- RNA-Binding Protein EWS/metabolism
- RNA-Binding Protein EWS/physiology
- Sarcoma, Ewing/genetics
- Sarcoma, Ewing/pathology
- Tenascin/biosynthesis
- Tenascin/genetics
- Transcription Factors/genetics
- Transcription Factors/immunology
- Transcription Factors/metabolism
- Transcription Factors/physiology
- Transcriptional Activation/genetics
- Transcriptional Activation/physiology
- Transfection
- Tumor Cells, Cultured
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Affiliation(s)
- Goichi Watanabe
- Department of Molecular Biology, Cancer Research Institute, Sapporo Medical University School of Medicine, Sapporo, Japan
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176
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Chan D, Wilson TJ, Xu D, Cowdery HE, Sanij E, Hertzog PJ, Kola I. Transformation induced by Ewing's sarcoma associated EWS/FLI-1 is suppressed by KRAB/FLI-1. Br J Cancer 2003; 88:137-45. [PMID: 12556973 PMCID: PMC2376791 DOI: 10.1038/sj.bjc.6600669] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Ewing's sarcoma is a childhood bone tumour with poor prognosis, most commonly associated with a t(11;22)(q24;q12) reciprocal translocation that fuses the EWS and FLI-1 genes, resulting in the production of an aberrant chimeric transcription factor EWS/FLI-1. To elucidate the mechanisms by which EWS/FLI-1 mediates transformation in mouse models, we have generated a murine Ews/Fli-1 fusion protein. We demonstrate that this protein transforms fibroblast cells in vitro similar to human EWS/FLI-1 as demonstrated by serum and anchorage-independent growth, the formation of tumours in nude mice and elevation of the oncogenic marker c-myc. Furthermore, transformation of these cells was inhibited by a specific repressor, KRAB/FLI-1. The KRAB/FLI-1 repressor also suppressed the tumorigenic phenotype of a human Ewing's sarcoma cell line. These findings suggest that the transformed phenotype of Ewing's sarcoma cells can be reversed by using the sequence-specific FLI-1-DNA-binding domain to target a gene repressor domain. The inhibition of EWS/FLI-1 is the first demonstration of the KRAB domain suppressing the action of an ETS factor. This approach provides potential avenues for the elucidation of the biological mechanisms of EWS/FLI-1 oncogenesis and the development of novel therapeutic strategies.
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Affiliation(s)
- D Chan
- Centre for Functional Genomics and Human Diseases, Monash Institute of Reproduction and Development, Monash University, Melbourne, Australia
| | - T J Wilson
- Centre for Functional Genomics and Human Diseases, Monash Institute of Reproduction and Development, Monash University, Melbourne, Australia
- 7245-24-110, Pharmacia and Upjohn, 301 Henrietta Street, Kalamazoo, MI 49007, USA
| | - D Xu
- Centre for Functional Genomics and Human Diseases, Monash Institute of Reproduction and Development, Monash University, Melbourne, Australia
| | - H E Cowdery
- Centre for Functional Genomics and Human Diseases, Monash Institute of Reproduction and Development, Monash University, Melbourne, Australia
| | - E Sanij
- Centre for Functional Genomics and Human Diseases, Monash Institute of Reproduction and Development, Monash University, Melbourne, Australia
| | - P J Hertzog
- Centre for Functional Genomics and Human Diseases, Monash Institute of Reproduction and Development, Monash University, Melbourne, Australia
- Centre for Functional Genomics and Human Diseases, Monash Institute of Reproduction and Development, Monash University, Melbourne, Australia. E-mail:
| | - I Kola
- Centre for Functional Genomics and Human Diseases, Monash Institute of Reproduction and Development, Monash University, Melbourne, Australia
- 7245-24-110, Pharmacia and Upjohn, 301 Henrietta Street, Kalamazoo, MI 49007, USA
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177
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Palmer RE, Lee SB, Wong JC, Reynolds PA, Zhang H, Truong V, Oliner JD, Gerald WL, Haber DA. Induction of BAIAP3 by the EWS-WT1 chimeric fusion implicates regulated exocytosis in tumorigenesis. Cancer Cell 2002; 2:497-505. [PMID: 12498718 DOI: 10.1016/s1535-6108(02)00205-2] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Desmoplastic small round cell tumor (DSRCT) is defined genetically by the chimeric fusion of the Ewing's sarcoma and Wilms' tumor genes, generating a novel transcription factor, EWS-WT1. By using cells with inducible EWS-WT1 to screen high-density microarrays, we identified BAIAP3 as a transcriptional target of the chimera. The BAIAP3 promoter is specifically bound in vivo by the (-KTS) isoform of EWS-WT1, consistent with its activation in reporter assays. BAIAP3 encodes a protein implicated in regulated exocytosis, which is colocalized with a secreted growth factor within cytoplasmic organelles. Ectopic expression of BAIAP3 in tumor cells dramatically enhances growth in low serum and colony formation in soft agar. BAIAP3 therefore encodes a transcriptional target of an oncogenic fusion protein that implicates the regulated exocytotic pathway in cancer cell proliferation.
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MESH Headings
- Angiogenesis Inhibitors
- Animals
- Base Sequence
- Blotting, Northern
- Carcinoma, Small Cell/genetics
- Carcinoma, Small Cell/metabolism
- Cell Transformation, Neoplastic/genetics
- Exocytosis/physiology
- Gene Expression Regulation, Neoplastic
- Genes, Wilms Tumor
- Humans
- In Situ Hybridization
- Molecular Sequence Data
- Mosaicism
- Oncogene Proteins, Fusion/genetics
- Osteosarcoma/genetics
- Osteosarcoma/metabolism
- Promoter Regions, Genetic
- Proteins/genetics
- Proteins/metabolism
- RNA-Binding Protein EWS/genetics
- Transcription, Genetic
- Tumor Cells, Cultured/ultrastructure
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Affiliation(s)
- Rachel E Palmer
- Massachusetts General Hospital Cancer Center and Harvard Medical School, Charlestown, MA 02129, USA
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178
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Nishimori H, Sasaki Y, Yoshida K, Irifune H, Zembutsu H, Tanaka T, Aoyama T, Hosaka T, Kawaguchi S, Wada T, Hata JI, Toguchida J, Nakamura Y, Tokino T. The Id2 gene is a novel target of transcriptional activation by EWS-ETS fusion proteins in Ewing family tumors. Oncogene 2002; 21:8302-9. [PMID: 12447693 DOI: 10.1038/sj.onc.1206025] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2002] [Revised: 08/08/2002] [Accepted: 10/04/2002] [Indexed: 11/09/2022]
Abstract
We report here that the Id2 (inhibitor of DNA binding 2) gene is a novel target of transcriptional activation by EWS-FLI1 and EWS-ERG, two fusion proteins that characterize Ewing family tumors (EFTs). To identify downstream targets of these EWS-ETS fusion proteins, we introduced EWS-ETS fusion constructs into a human fibrosarcoma cell line by retroviral transduction. cDNA microarray analysis revealed that Id2 expression was up-regulated by introducing the EWS-ETS fusion gene but not by the normal full-length ETS gene. An Id2 promoter-luciferase reporter assay showed that transactivation by EWS-ETS involves the minimal Id2 promoter and may function in cooperation with c-Myc within the full-length regulatory region. A chromatin immunoprecipitation assay revealed direct interaction between the Id2 promoter and EWS-FLI1 fusion protein in vivo. Significantly higher expression of Id2 and c-Myc was observed in all of the six EFT cell lines examined compared to six other sarcoma cell lines. Moreover, high levels of Id2 expression were also observed in five of the six primary tumors examined. Id2 is generally thought to affect the balance between cell differentiation and proliferation in development and is highly expressed in several cancer types. Considering these previous studies, our data suggest that the oncogenic effect of EWS-ETS may be mediated in part by up-regulating Id2 expression. doi:10.1038/sj.onc.1206025
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Affiliation(s)
- Hiroyuki Nishimori
- Department of Molecular Biology, Cancer Research Institute, Sapporo Medical University School of Medicine, S-1, W-17, Chuo-ku, Sapporo, 060-8556, Japan
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179
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Sancéau J, Poupon MF, Delattre O, Sastre-Garau X, Wietzerbin J. Strong inhibition of Ewing tumor xenograft growth by combination of human interferon-alpha or interferon-beta with ifosfamide. Oncogene 2002; 21:7700-9. [PMID: 12400012 DOI: 10.1038/sj.onc.1205881] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2002] [Revised: 07/05/2002] [Accepted: 07/18/2002] [Indexed: 11/09/2022]
Abstract
Ewing sarcoma is the second most common bone tumor in childhood. Despite aggressive chemotherapy and radiotherapy strategies, the prognosis of patients with metastatic disease remains poor. We have recently reported that Ewing tumor cell proliferation was strongly inhibited by IFN-beta and to a lesser degree by IFN-alpha. Moreover, under IFN-beta treatment, some cell lines undergo apoptosis. Since the possibility of using IFNs for Ewing tumor treatments may be of interest, we have evaluated the efficacy of Hu-IFNs in a nude mice model of Ewing tumor xenografts. The results reported here show that human type I IFNs, Hu-IFN-alpha and Hu-IFN-beta impaired tumor xenograft take and displayed an anti-growth effect toward established xenografts. Furthermore, we have also shown that combined therapy with Hu-IFNs and ifosfamide (IFO), an alkylating agent widely used in high-dose chemotherapy of Ewing tumors, results in a strong antitumor effect. Pathological analysis showed that Hu-IFN-alpha/IFO and Hu-IFN-beta/IFO were characterized by a dramatic decrease in the mitotic index and marked necrosis, as well as extensive fibrosis associated with numerous calcifications. To our knowledge, this is the first demonstration of a potential antitumor effect of human type I IFNs and IFO on Ewing tumors, providing a rational foundation for a promising therapeutic approach to Ewing sarcoma.
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Affiliation(s)
- Josiane Sancéau
- INSERM U365, Institut Curie, Section Recherche 26, rue d'Ulm, 75 248 - Paris Cedex 05, France
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180
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Sandberg AA, Bridge JA. Updates on the cytogenetics and molecular genetics of bone and soft tissue tumors. desmoplastic small round-cell tumors. CANCER GENETICS AND CYTOGENETICS 2002; 138:1-10. [PMID: 12419577 DOI: 10.1016/s0165-4608(02)00680-5] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Avery A Sandberg
- Department of DNA Diagnostics, St. Joseph's Hospital and Medical Center, 350 West Thomas Road, Phoenix, AZ 85013, USA.
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181
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Ozaki T, Schaefer KL, Wai D, Yokoyama R, Ahrens S, Diallo R, Hasegawa T, Shimoda T, Hirohashi S, Kawai A, Naito N, Morimoto Y, Inoue H, Boecker W, Juergens H, Winkelmann W, Dockhorn-Dworniczak B, Poremba C. Population-based genetic alterations in Ewing's tumors from Japanese and European Caucasian patients. Ann Oncol 2002; 13:1656-64. [PMID: 12377657 DOI: 10.1093/annonc/mdf218] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND The incidence of Ewing's tumors (ETs) is lower in Asians or African-Americans than in Caucasians. PATIENTS AND METHODS Japanese ETs were available for analysis of chromosomal aberrations by comparative genomic hybridization (n = 16) and for expression of chimeric EWS transcripts by reverse-transcriptase polymerase chain reaction (n = 11). These results in Japanese patients were compared with those of 62 ETs in European Caucasian patients registered in the European Intergroup Cooperative Ewing's Sarcoma Study. RESULTS Japanese patients with ET had lower overall survival (P = 0.0446) and relapse-free survival (P = 0.0371) compared with European Caucasian patients. Ten of 11 Japanese ETs and 31 of 62 European Caucasian ETs had type I (EWS exon 7 to FLI1 exon 6) fusion transcripts. In Japanese ETs, the median numbers of chromosomal aberrations were 2.0 and 6.0 in 11 primary tumors and five relapsed tumors, respectively. In European Caucasian ETs, the median number of changes were 2.5 and 5.0 in 52 primary and 10 relapsed tumors, respectively. Frequent gains were 8q (38%), 8p (31%) and 12q (25%) in Japanese ETs and 8q (52%), 8p (48%) and 12q (19%) in European Caucasian ETs. Frequent losses were 19q (44%), 19p (38%) and 17p (25%) in Japanese ETs and 16q (21%), 19q (18%) and 17p (15%) in European Caucasian ETs. The incidence of losses of 19p (P = 0.0215) and 19q (P = 0.0277) were significantly higher in Japanese ETs than in European Caucasian ETs. An amplification (1p33-p34) was observed in only one Japanese ET. CONCLUSIONS Japanese patients with ET in this study had a worse prognosis than European Caucasian patients. In molecular genetic analyses, Japanese ETs had a higher frequency of loss of chromosome 19 than European Caucasian ETs. Different genetic aberrations may explain the different incidences and prognoses of ET between Caucasian and Japanese patients.
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Affiliation(s)
- T Ozaki
- Department of Orthopaedics, Westfaelische Wilhelms-University, Münster, Germany
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182
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Iijima Y, Okuda K, Tojo A, Tri NK, Setoyama M, Sakaki Y, Asano S, Tokunaga K, Kruh GD, Sato Y. Transformation of Ba/F3 cells and Rat-1 cells by ETV6/ARG. Oncogene 2002; 21:4374-83. [PMID: 12080468 DOI: 10.1038/sj.onc.1205544] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2001] [Revised: 03/27/2002] [Accepted: 04/02/2002] [Indexed: 11/09/2022]
Abstract
ETV6/ARG, a novel fusion gene composed of the ETV6 HLH oligomerization domain and most of sequences of the ARG protein tyrosine, was recently identified in human leukemia cells. The presence of the ETV6/ARG translocation raises the possibility that the resulting fusion protein functions as an oncogene. However, the transforming activity of the ETV6/ARG protein has not been determined and its contribution to leukemogenesis is therefore unknown. Here we address this question by analysing the oncogenic activity of ETV6/ARG in hematopoietic and fibroblast cells. It is demonstrated that expression of ETV6/ARG confers IL3-independent growth to Ba/F3 cells and anchorage independent growth to Rat-1 fibroblasts. It is also shown that multiple signaling molecules, including PI3K, SHC, ras-GAP and CRK-L, are tyrosine phosphorylated in Ba/F3 cells that express ETV6/ARG. Analysis of four different types of ETV6/ARG transcripts previously identified in the AML-M3 leukemia cell line HT93A suggest that ETV6 HLH domain is required for oncogenic activity. Based upon these results it is concluded that ARG can be activated as an oncogene in human malignancy and that the ETV6/ARG oncoprotein triggers some of the same signaling pathways associated with activated ABL oncogenes.
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Affiliation(s)
- Yoshimi Iijima
- Division of Molecular Cytogenetics, Department of Clinical Pathology, Research Institute, International Medical Center of Japan, Tokyo 162-0052, Japan
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183
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Zwerner JP, May WA. Dominant negative PDGF-C inhibits growth of Ewing family tumor cell lines. Oncogene 2002; 21:3847-54. [PMID: 12032822 DOI: 10.1038/sj.onc.1205486] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2001] [Revised: 02/28/2002] [Accepted: 03/18/2002] [Indexed: 12/12/2022]
Abstract
Nearly all cases of Ewing Family Tumors (EFT) harbor chimeric EWS/ETS transcription factors which are thought to aberrantly regulate transcriptional targets of phenotypic consequence. We have recently demonstrated that EWS/ETS proteins up-regulate platelet derived growth factor-C (PDGF-C), a novel transforming growth factor. To determine if PDGF-C signaling contributes to the malignant phenotype of EFT cell lines, we attempted to disrupt this presumed autocrine loop. AG1296, a PDGF receptor selective tyrosine kinase inhibitor, markedly inhibits anchorage-independent growth in an EFT cell line. To effect specific disruption, we have developed a dominant negative form of PDGF-C which is appropriately secreted and processed. This mutant has greatly reduced activity as a PDGF receptor agonist. When co-expressed with PDGF-C in a fibroblast transformation model, this dominant negative dramatically inhibits anchorage-independent growth. When this mutant is expressed in EFT cell lines, there is a similar reduction in anchorage-independent growth. This demonstrates that specific inhibition of PDGF-C signaling in EFT cell lines partially reverts their phenotype. These data support a significant role of PDGF-C in the biology of EFT. They also suggest that PDGF-C driven signaling may be a possible therapeutic target of more clinically relevant tyrosine kinase inhibitors.
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Affiliation(s)
- Jeffrey P Zwerner
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35242, USA
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184
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Lessnick SL, Dacwag CS, Golub TR. The Ewing's sarcoma oncoprotein EWS/FLI induces a p53-dependent growth arrest in primary human fibroblasts. Cancer Cell 2002; 1:393-401. [PMID: 12086853 DOI: 10.1016/s1535-6108(02)00056-9] [Citation(s) in RCA: 188] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ewing's sarcoma is associated with a fusion between the EWS and FLI1 genes, forming an EWS/FLI fusion protein. We developed a system for the identification of cooperative mutations in this tumor through expression of EWS/FLI in primary human fibroblasts. Gene expression profiling demonstrated that this system recapitulates many features of Ewing's sarcoma. EWS/FLI-expressing cells underwent growth arrest, suggesting that growth arrest-abrogating collaborative mutations may be required for tumorigenesis. Expression profiling identified transcriptional upregulation of p53, and the growth arrest was rescued by inhibition of p53. These data support a role for p53 as a tumor suppressor in Ewing's sarcoma and demonstrate the use of transcriptional profiling of model systems in the identification of cooperating mutations in human cancer.
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Affiliation(s)
- Stephen L Lessnick
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA 02115, USA
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185
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Bertuzzi A, Castagna L, Nozza A, Quagliuolo V, Siracusano L, Balzarotti M, Compasso S, Alloisio M, Soto Parra H, Santoro A. High-dose chemotherapy in poor-prognosis adult small round-cell tumors: clinical and molecular results from a prospective study. J Clin Oncol 2002; 20:2181-8. [PMID: 11956280 DOI: 10.1200/jco.2002.08.033] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
PURPOSE The prognosis of metastatic/high-risk localized small round-cell tumors (SRCTs) treated conventionally is dismal. In this phase II study, we explored a high-dose chemotherapy (HD-CT) approach and analyzed the clinical significance of fusion transcripts detection. PATIENTS AND METHODS From June 1997 to November 1999, 28 SRCT patients (median age, 26 years; 14 peripheral primitive neuroectodermal tumors [pPNETs], seven rhabdomyosarcomas [RMSs], and seven desmoplastic small round-cell tumors [DSRCTs]) received induction chemotherapy with ifosfamide, epirubicin, and vincristine followed by HD-CT. Local treatment (radiotherapy and/or surgery) was performed when possible. Molecular analysis was performed on peripheral-blood and leukapheresis products by reverse-transcriptase polymerase chain reaction. RESULTS Overall response (OR) was 65% (18 of 28), with 40% complete response and 25% partial response. According to histology, the OR rate was 86% in pPNET and 43% in both RMS DSRCT. With a median follow-up of 35 months, median overall survival was 16 months and median progression-free survival (PFS) was 10 months. PFS was statistically better in pPNET than other histologic types (P =.0045). No correlation was found between the fusion transcript and clinical outcome during follow-up. Furthermore, transcript detection in leukapheretic products was not of prognostic significance. CONCLUSION Intensive HD-CT seems to enhance the response rate and survival when compared with conventional treatment in poor-prognosis pPNET. The poor results of this treatment in RMS and DSRCT do not support the inclusion of such an approach in these patient subsets. No definitive conclusions can currently be drawn concerning the clinical implications of the detection of fusion transcripts during treatment or follow-up.
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Affiliation(s)
- Alexia Bertuzzi
- Department of Medical Oncology and Hematology, Istituto Clinico Humanitas, Rozzano, Milan, Italy.
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186
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Wong JC, Lee SB, Bell MD, Reynolds PA, Fiore E, Stamenkovic I, Truong V, Oliner JD, Gerald WL, Haber DA. Induction of the interleukin-2/15 receptor beta-chain by the EWS-WT1 translocation product. Oncogene 2002; 21:2009-19. [PMID: 11960373 DOI: 10.1038/sj.onc.1205262] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2001] [Revised: 12/11/2001] [Accepted: 12/18/2001] [Indexed: 11/08/2022]
Abstract
EWS-WT1 is a chimeric transcription factor resulting from fusion of the N-terminal domain of the Ewing sarcoma gene EWS to the three C-terminal zinc fingers of the Wilms tumor suppressor WT1. This translocation underlies desmoplastic small round cell tumor (DSRCT), which is noted for the abundance of reactive stroma surrounding islets of tumor cells, suggestive of paracrine signals contributing to tumor cell proliferation. Hybridization to high-density oligonucleotide microarrays can be used to identify targets of EWS-WT1. Expression of EWS-WT1 from a tetracycline-regulated promoter leads to the induction of growth-associated genes, of which the most remarkable is the beta-chain of the interleukin-2/15 receptor (IL-2/15Rbeta). Potent transcriptional activation by the chimeric protein maps to two bindings sites within the IL-2/15Rbeta promoter. Analysis of primary DSRCT tumor specimens demonstrates high levels of IL-2/15Rbeta within the tumor cells, along with expression of IL-2 and IL-15 by the abundant hyperplastic endothelial cells within the reactive stroma. Activation of this cytokine signaling pathway is consistent with the nuclear localization of its downstream effectors, phosphorylated STAT3 and STAT5. These observations suggest that the transcriptional induction of a cytokine receptor by a tumor-associated translocation product enables a proliferative response of epithelial cancer cells to ligands secreted by the surrounding stroma.
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MESH Headings
- Abdominal Neoplasms/genetics
- Abdominal Neoplasms/metabolism
- Abdominal Neoplasms/pathology
- Carcinoma, Small Cell/genetics
- Carcinoma, Small Cell/metabolism
- Carcinoma, Small Cell/pathology
- DNA-Binding Proteins/metabolism
- Electrophoretic Mobility Shift Assay
- Gene Expression Regulation, Neoplastic
- Humans
- Immunohistochemistry
- Interleukin-2/metabolism
- Interleukin-2 Receptor beta Subunit
- Interleukin-5/metabolism
- Janus Kinase 1
- Janus Kinase 3
- Male
- Milk Proteins
- Oligonucleotide Array Sequence Analysis
- Oncogene Proteins, Fusion/genetics
- Oncogene Proteins, Fusion/metabolism
- Promoter Regions, Genetic
- Protein-Tyrosine Kinases/metabolism
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Receptors, Interleukin/biosynthesis
- Receptors, Interleukin/genetics
- Receptors, Interleukin/metabolism
- Receptors, Interleukin-15
- Receptors, Interleukin-2/metabolism
- Response Elements/genetics
- STAT3 Transcription Factor
- STAT5 Transcription Factor
- Signal Transduction
- Trans-Activators/metabolism
- Transcription, Genetic
- Tumor Cells, Cultured
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Affiliation(s)
- Jenise C Wong
- Massachusetts General Hospital Cancer Center and Harvard Medical School, Charlestown, Massachusetts, MA 02129, USA
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187
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Van Rompaey L, Holland E, Grosveld G. TEL Induces Aggregation in Transformed Cells and Induces Tube Formation in NIH3T3-UCLA Cells. Biochem Biophys Res Commun 2002; 291:820-8. [PMID: 11866439 DOI: 10.1006/bbrc.2002.6513] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
TEL/ETV6 is the frequent target of translocations associated with lymphoid and myeloid leukemias and solid tumors. We show that TEL induces aggregation of immortalized and transformed fibroblasts, endothelial cells and astrocytes. These aggregates form cellular cords in NIH3T3-UCLA by a cell autonomous process, which occurs when the monolayer is made up of over 75% of cells expressing exogenous TEL. Cords with a diameter of 15-25 microm contain a lumen and occur as tube structures. The possible relevance for vasculogenic mimicry is discussed. By contrast TEL did not induce aggregation of regular NIH3T3 cells, an effect that could only be induced by co-expression of oncogenic RAS/Lys12. Also transduction of TEL and RAS retroviral vectors into the endothelial MS1 cell line and TEL alone in the highly transformed glioblastoma cell lines EH-A and EH-B resulted in extensive aggregation. Thus, the induction of cellular aggregation by TEL correlates with transformation.
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Affiliation(s)
- L Van Rompaey
- Department of Genetics, St. Jude Children's Research Hospital, Memphis, Tennessee
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188
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Jimenez RE, Folpe AL, Lapham RL, Ro JY, O'Shea PA, Weiss SW, Amin MB. Primary Ewing's sarcoma/primitive neuroectodermal tumor of the kidney: a clinicopathologic and immunohistochemical analysis of 11 cases. Am J Surg Pathol 2002; 26:320-7. [PMID: 11859203 DOI: 10.1097/00000478-200203000-00005] [Citation(s) in RCA: 158] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Ewing's sarcoma/primitive neuroectodermal tumor (ES/PNET) is an extraordinarily rare primary tumor in the kidney and can be mistaken for a variety of other round cell tumors, including blastema-predominant Wilms' tumor (WT). Approximately 90% of ES/PNET have a specific t(11;22), which results in a chimeric EWS-FLI-1 protein. Immunohistochemistry for the carboxy-terminus of FLI-1 is sensitive and highly specific for the diagnosis of ES/PNET. WT-1, the WT-associated tumor suppressor gene, is overexpressed in WT but not in ES/PNET. No study has examined FLI-1 or WT-1 expression in renal ES/PNET. The clinicopathologic features of 11 renal ES/PNET were studied along with immunohistochemistry for cytokeratin, desmin, CD99, FLI-1, and WT-1. WT were also immunostained for CD99 (5 cases), FLI-1 (10 cases), and WT-1 (9 cases). The patients (6 men, 5 women) ranged from 18 to 49 years of age (mean, 34 yr). The mean tumor size was 11.8 +/- 3.8 cm (mean +/- standard deviation). Presenting symptoms included abdominal/flank pain and/or hematuria. Grossly, all tumors showed necrosis and hemorrhage, and 4 had cystic change. Microscopically, all tumors showed vaguely lobular growth, primitive round cells, and variable rosette formation. Epithelial, myogenous, or cartilaginous differentiation was not seen. Immunohistochemical results on the renal ES/PNET were cytokeratin (2/8 focal), desmin (0/9), CD99 (8/8), FLI-1 (5/8), and WT-1 (0/8). In comparison, the WT only rarely expressed CD99 (1/5) and did not express FLI-1 (0/10), but were usually WT-1-positive (7/9). Follow-up on 8 cases (mean, 28 mo; range, 6-64 mo) showed 4 lung and pleural metastases, 1 bone metastasis, liver metastasis, 2 local recurrences, and 5 deaths from disease (median time to death, 16.8 mo). No case had distant metastatic disease at presentation. Adjuvant therapy included chemotherapy (8 cases), radiation (3 cases), and bone marrow transplantation (1 case). Our study affirms a unique proclivity of renal ES/PNET for young adults and that it is a highly aggressive neoplasm, with rapid death in many cases, usually after the development of treatment-resistant lung metastases. These tumors must be distinguished from blastema-predominant WT and other primitive renal tumors that require different therapy. FLI-1 and WT-1 immunohistochemistry may be valuable in this differential diagnosis, given the known immunophenotypic overlap between ES/PNET and blastema-predominant WT with regard to CD99, cytokeratin, and desmin. The accurate distinction between these two entities has clear prognostic and therapeutic implications.
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MESH Headings
- 12E7 Antigen
- Adult
- Aged
- Antigens, CD/analysis
- Cell Adhesion Molecules/analysis
- Child
- Combined Modality Therapy
- DNA-Binding Proteins/analysis
- Desmin/analysis
- Diagnosis, Differential
- Female
- Genes, Tumor Suppressor
- Humans
- Immunohistochemistry
- Keratins/analysis
- Kidney Neoplasms/chemistry
- Kidney Neoplasms/genetics
- Kidney Neoplasms/pathology
- Kidney Neoplasms/therapy
- Male
- Middle Aged
- Neoplasm Metastasis
- Neuroectodermal Tumors, Primitive/chemistry
- Neuroectodermal Tumors, Primitive/genetics
- Neuroectodermal Tumors, Primitive/pathology
- Neuroectodermal Tumors, Primitive/therapy
- Proto-Oncogene Protein c-fli-1
- Proto-Oncogene Proteins
- Sarcoma, Ewing/chemistry
- Sarcoma, Ewing/genetics
- Sarcoma, Ewing/pathology
- Sarcoma, Ewing/therapy
- Trans-Activators/analysis
- WT1 Proteins/analysis
- Wilms Tumor/chemistry
- Wilms Tumor/genetics
- Wilms Tumor/pathology
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Affiliation(s)
- Rafael E Jimenez
- Department of Pathology, Emory University School of Medicine, Atlanta, Georgia, USA
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189
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Ohkura N, Yaguchi H, Tsukada T, Yamaguchi K. The EWS/NOR1 fusion gene product gains a novel activity affecting pre-mRNA splicing. J Biol Chem 2002; 277:535-43. [PMID: 11673470 DOI: 10.1074/jbc.m109018200] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In extraskeletal myxoid chondrosarcoma, chromosomal translocation creates a gene fusion between EWS and the orphan nuclear receptor NOR1. The resulting fusion gene product, EWS/NOR1, has been believed to lead to malignant transformation by functioning as a transcriptional activator, but an alternative mechanism may also be involved. Here, using a newly developed functional complementation screening in yeast, we found that EWS/NOR1, but not EWS or NOR1, complemented the loss of function of the small nuclear ribonucleoprotein Snu23p, an essential factor for pre-mRNA splicing in yeast. To verify the potential function of EWS/NOR1 in mammalian cells, we next showed that overexpression of EWS/NOR1 caused increased usage of the distal 5'-splice site of pre-mRNA splicing and that EWS/NOR1 interacted with the human splicing protein U1C; neither EWS nor NOR1 had the same activity or interaction as EWS/NOR1. Altogether, our findings reveal that EWS/NOR1 gains a novel activity affecting pre-mRNA splicing.
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Affiliation(s)
- Naganari Ohkura
- Growth Factor Division, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan.
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190
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191
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Welford SM, Hebert SP, Deneen B, Arvand A, Denny CT. DNA binding domain-independent pathways are involved in EWS/FLI1-mediated oncogenesis. J Biol Chem 2001; 276:41977-84. [PMID: 11553628 DOI: 10.1074/jbc.m106757200] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Specific chromosomal translocations involving the ews gene and one of five members of the ets family of transcription factors create ews/ets fusion genes that are found in approximately 85% of Ewing's family of tumors. ews/ets fusion genes consistently maintain an intact and functional ets DNA binding domain (DBD) in all of these cases. We demonstrate here, however, that EWS/FLI1, the most prevalent EWS/ETS fusion, activates oncogenic pathways independent of its DBD. In in vivo tumor assays, EWS/FLI1 molecules with either point mutations or a large deletion in the ets DBD retain the ability to accelerate tumors in NIH 3T3 cells, whereas they lose the ability to bind DNA in vitro. Additionally, whereas inhibition of DBD functions of EWS/FLI1 with a dominant negative form of FLI1 is sufficient to inhibit anchorage-independent growth in NIH 3T3 cells, it is ineffective in inhibiting tumor growth in SCID mice. Usage of this dominant negative construct in a Ewing's tumor cell line, however, does reduce the rate of tumor formation, supporting the need for a functional DBD in this context. Together, these results suggest that EWS/FLI1 induces both DBD-dependent and DBD-independent oncogenic pathways.
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Affiliation(s)
- S M Welford
- Molecular Biology Institute, UCLA, Los Angeles, California 90095, USA
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192
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Abstract
Transdifferentiation is a process in which a stable cell's phenotype changes to that of a distinctly different cell type. It occurs during certain physiological processes and leads to transition of tumor cell phenotypes. The latter process includes neoplastic epithelial-epithelial transition, neoplastic epithelial-mesenchymal transition, neoplastic mesenchymal-epithelial transition and transition between non-neural and neural neoplastic cell. This phonomenon is exemplified in some origin-debated tumors, such as carcinosarcoma, pleomorphic adenoma, synovial sarcoma, Ewing's/pPNET, and malignant fibrohistiocytoma. We propose that differentiation disturbance of cancer cells should include not only undifferentiation and dedifferentiation, but also transdifferentiation as well. Tumor cell transdifferentiation may be influenced or determined by cellular genetic instabilities, proliferation and apoptosis, as well as by extracellular matrix and growth factors.
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Affiliation(s)
- Z Zhang
- Department of Pathology, Dalian Medical University, 465 Zhongshan Road, Dalian 116027, PR China
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193
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Affiliation(s)
- K H Antman
- Department of Medicine, Columbia University, College of Physicians and Surgeons, New York, NY, USA
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194
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Fujimura Y, Siddique H, Lee L, Rao VN, Reddy ES. EWS-ATF-1 chimeric protein in soft tissue clear cell sarcoma associates with CREB-binding protein and interferes with p53-mediated trans-activation function. Oncogene 2001; 20:6653-9. [PMID: 11709699 DOI: 10.1038/sj.onc.1204684] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2001] [Revised: 05/23/2001] [Accepted: 05/31/2001] [Indexed: 11/09/2022]
Abstract
The recurrent t(12;22) (q13;q12) chromosomal translocation associated with soft tissue clear cell sarcoma results in a chimeric protein EWS-ATF-1 that acts as a constitutive transcriptional activator. The CBP/p300 transcriptional coactivator, which links various transcriptional factors to basal transcription apparatus, participates in transcriptional activation, growth and cell cycle control and differentiation. In this study, we show that EWS-ATF-1 associates constitutively with CBP both in vitro and in vivo. Both EWS and ATF-1 fusion domains are needed for this interaction. Here, we demonstrate that EWS-ATF-1 represses p53/CBP-mediated trans-activation function. Overexpression of CBP can counteract this repressive effect of EWS-ATF-1. Taken together, these findings suggest that one of the mechanisms by which EWS-ATF-1 may cause tumors is through targeting CBP/p300 resulting in the loss of function of p53. This novel mechanism may be responsible for the development of these and other related solid tumors.
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MESH Headings
- Blotting, Western
- Dose-Response Relationship, Drug
- Genes, p53
- Glutathione Transferase/metabolism
- Humans
- Models, Genetic
- Nuclear Proteins/metabolism
- Oncogene Proteins, Fusion/metabolism
- Plasmids/metabolism
- Precipitin Tests
- Protein Binding
- Protein Structure, Tertiary
- Sarcoma, Clear Cell/genetics
- Sarcoma, Clear Cell/metabolism
- Soft Tissue Neoplasms/genetics
- Soft Tissue Neoplasms/metabolism
- Trans-Activators/metabolism
- Transcription Factors
- Transcription, Genetic
- Transcriptional Activation
- Transfection
- Tumor Cells, Cultured
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Affiliation(s)
- Y Fujimura
- Program of Cancer Genetics, Department of Biochemistry, School of Medicine, MCP Hahnemann University, Broad and Vine, Philadelphia, PA 19102, USA
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195
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Ozaki T, Paulussen M, Poremba C, Brinkschmidt C, Rerin J, Ahrens S, Hoffmann C, Hillmann A, Wai D, Schaefer KL, Boecker W, Juergens H, Winkelmann W, Dockhorn-Dworniczak B. Genetic imbalances revealed by comparative genomic hybridization in Ewing tumors. Genes Chromosomes Cancer 2001; 32:164-71. [PMID: 11550284 DOI: 10.1002/gcc.1178] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Ewing tumors are characterized by reciprocal translocations involving the EWS gene on 22q12 fused to ETS transcription-factor family members. Little is known about further aberrations contributing to tumor development and progression. Sixty-two frozen tumors with known EWS rearrangements (52 primary tumors, 10 relapses) of ET patients registered in the EICESS protocol were analyzed by comparative genomic hybridization (CGH). The median number of changes in 52 primary and 10 relapsed cases was 2.5 and 5.0 per tumor (P = 0.153). Frequent abnormalities included gains of chromosomes 8, 12, 20, and 1q and losses of 16q and 19q. Neither number nor type of aberration was associated with histology, tumor size, disease stage, tumor localization, or histologic tumor response to chemotherapy. Among the 52 primary tumors, 26 with Type I fusion (EWS exon 7 to FLI1 exon 6) and 26 with other fusion types had a median of 2.0 and 3.0 aberrations per tumor, respectively (P = 0.031). Combinations of gains of chromosomes 8 and 12, gains of chromosome 20, and either gains of 8q or 18q and losses of 16q and 17p frequently occurred. The cumulative overall survival (OAS) was different between 35 patients with <5 aberrations and 13 patients with > or =5 aberrations (P = 0.009). Univariate analysis showed that patients with gains of 1q, 2q, 12, and 20 or losses of 16q and 17p had significantly lower OAS than those without aberrations. By multivariate analysis, loss of 16q (relative risk [RR] = 5.3; P = 0.0006) was an independent prognostic factor.
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Affiliation(s)
- T Ozaki
- Department of Orthopaedics, Westfälische Wilhelms-University, Domagkstrasse 17, 48149 Münster, Germany
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196
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Abstract
Tumor-associated chromosomal translocations lead to the formation of chimeric fusions between the EWS gene and one of five different ETS transcription factors in Ewing's family tumors (EFTs). The resultant EWS/ETS proteins promote oncogenesis in a dominant fashion in model systems and are necessary for continued growth of EFT cell lines. EWS belongs to a family of genes that encode proteins that may serve as adapters between the RNA polymerase II complex and RNA splicing factors. EWS/ETS fusions have biochemical characteristics of aberrant transcription factors and appear to promote abnormal cellular growth by transcriptionally modulating a network of target genes. Early evidence suggests that EWS/ETS proteins may also impact gene expression through alteration in RNA processing. Elucidation of EWS/ETS target gene networks in the context of other signaling pathways will hopefully lead to biology based therapeutic strategies for EFT.
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Affiliation(s)
- A Arvand
- Department of Pathology and Laboratory Medicine, Gwynne Hazen Cherry Memorial Labs, University of California at Los Angeles, California, USA
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197
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Affiliation(s)
- E de Alava
- Departamento de Anatomía Patológica, Clínica Universitaria de Navarra, Universidad de Navarra, Pamploma, Spain.
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198
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Abstract
Advances in molecular genetic research in the past 2 decades have led to an increased understanding of the genetic events in the pathogenesis and progression of human malignancies, including those of childhood. A number of pediatric malignancies have served as models for the molecular genetic approach to patients with cancer. These have highlighted the utility of molecular analysis for a variety of purposes including diagnosis, risk stratification and treatment planning, understanding of syndromes associated with cancer and genetic screening, genetic counseling and prophylactic treatment including surgery. It is likely that there soon will be individualized treatment regimens based on the molecular biologic profile of a patient's tumor. In addition, molecular profiling will lead to new drug development designed to induce differentiation of tumor cells, block dysregulated growth pathways, or reactivate silenced apoptotic pathways. This review discusses the molecular genetic aspects of some of the more common pediatric tumors as well as tumors whose pathogenetic mechanisms are particularly instructive.
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Affiliation(s)
- A M Davidoff
- Department of Surgery, St Jude Children's Research Hospital, Memphis, TN 38105, USA
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199
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Folpe AL, Chand EM, Goldblum JR, Weiss SW. Expression of Fli-1, a nuclear transcription factor, distinguishes vascular neoplasms from potential mimics. Am J Surg Pathol 2001; 25:1061-6. [PMID: 11474291 DOI: 10.1097/00000478-200108000-00011] [Citation(s) in RCA: 166] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Fli-1 protein, a member of the ETS family of DNAbinding transcription factors, is involved in cellular proliferation and tumorigenesis. Approximately 90% of Ewing's sarcoma/primitive neuroectodermal tumors (ES/PNET) have a specific translocation, t(11;22)(q24;q12), which results in fusion of EWS to Fli-1, and production of an EWS-Fli-1 fusion protein. We have recently shown that immunohistochemistry for the carboxy terminal of Fli-1 protein is sensitive and highly specific for the diagnosis of ES/PNET. In our earlier study we noted that among normal tissues only endothelial cells and small lymphocytes expressed Fli-1. Fli-1 expression in vascular neoplasms has not been previously studied. Formalin-fixed paraffin-embedded tissue from 54 vascular tumors and 75 nonvascular tumors were immunostained for Fli-1 (1:120, Sc 356, Santa Cruz Biotechnology, Santa Cruz, CA), after steam heat-induced epitope retrieval. Only cases with >10% of cells showing nuclear staining were accepted as positive. Cases without positive internal controls (endothelium and small lymphocytes) were not scored. Positive internal controls were present in 122 of 129 cases (95%). One vascular tumor (Kaposi's sarcoma) and 7 nonvascular tumors (2 epithelioid sarcomas and 5 carcinomas) without internal controls were not scored. Fli-1 was expressed by 50 of 53 vascular tumors scored (94%), including 20 of 22 angiosarcomas, 11 of 12 hemangioendotheliomas, 7 of 7 hemangiomas, and 12 of 12 Kaposi's sarcomas. In contrast, Fli-1 expression was absent in the 68 nonvascular tumors scored (0 of 68), including 16 sarcomas, 7 melanomas, and 45 carcinomas. The results of this study strongly suggest a role for Fli-1 as a novel marker of both benign and malignant vascular tumors. The sensitivity (94%) and specificity (100%) of Fli-1 with regards to the cases evaluated in this study equal or exceed those of the established vascular markers, CD31, CD34, and von Willebrand factor. As the first nuclear, rather than cytoplasmic or membranous marker of endothelium, Fli-1 immunostaining also generally lacks cytoplasmic staining artifacts that are the result of endogenous peroxidases or biotin.
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Affiliation(s)
- A L Folpe
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia, USA.
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200
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Feng L, Lee KA. A repetitive element containing a critical tyrosine residue is required for transcriptional activation by the EWS/ATF1 oncogene. Oncogene 2001; 20:4161-8. [PMID: 11464282 DOI: 10.1038/sj.onc.1204522] [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] [Received: 12/12/2000] [Revised: 04/09/2001] [Accepted: 04/09/2001] [Indexed: 11/08/2022]
Abstract
Chromosomal fusion of the N-terminal region of the Ewings Sarcoma Oncogene (EWS-activation-domain, EAD) to the DNA-binding domains of a variety of cellular transcription factors produce oncogenic proteins (EWS-fusion proteins (EFPs)) that cause distinct malignancies. In EFPs, the EAD acts as a potent transcriptional activation domain and this ability is repressed in the context of normal, non-tumorigenic, EWS. Trans-activation by the EAD is therefore a specific characteristic of EFPs and it is thought that EFPs induce tumorigenesis via improper transcriptional activation of cellular genes. Functional elements required for transcriptional activation are dispersed throughout the EAD, as are thirty-one copies of a Degenerate Hexapeptide Repeat (DHR, consensus SYGQQS). This suggests that the EAD contains a highly reiterated functional element related to DHRs. Here we show that in the context of EWS/ATF1, the EFP that causes malignant melanoma of soft parts, trans-cooperation by small regions of the EAD ( approximately 30 residues) results in potent transcriptional activation dependent on the conserved tyrosine residues present in DHRs. These findings provide the first evidence for a role of DHRs in EAD-mediated trans-activation and demonstrate that the EAD represents a novel tyrosine-dependent transcriptional activation domain.
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Affiliation(s)
- L Feng
- Department of Biology, Hong Kong University of Science & Technology, Clear Water Bay, Kowloon, Hong Kong, S.A.R. China
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