1
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Ho C, Nael A, Sato M, Crawford JR. Primary intracranial Ewing sarcoma in an infant. BMJ Case Rep 2023; 16:e255110. [PMID: 37640410 PMCID: PMC10462961 DOI: 10.1136/bcr-2023-255110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/31/2023] Open
Affiliation(s)
- Clarice Ho
- University of Nevada Reno School of Medicine, Reno, Nevada, USA
| | - Ali Nael
- Department of Pathology, Children's Hospital of Orange County, Orange, California, USA
- Department of Pathology, University of California Irvine Medical Center, Orange, California, USA
| | - Mariko Sato
- Department of Pediatrics, Children's Hospital Orange County, Orange, California, USA
| | - John Ross Crawford
- Department of Pediatrics, Children's Hospital Orange County, Orange, California, USA
- Department of Pediatrics, University of California Irvine, Irvine, California, USA
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2
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ETV6 dependency in Ewing sarcoma by antagonism of EWS-FLI1-mediated enhancer activation. Nat Cell Biol 2023; 25:298-308. [PMID: 36658219 PMCID: PMC10101761 DOI: 10.1038/s41556-022-01060-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 11/24/2022] [Indexed: 01/21/2023]
Abstract
The EWS-FLI1 fusion oncoprotein deregulates transcription to initiate the paediatric cancer Ewing sarcoma. Here we used a domain-focused CRISPR screen to implicate the transcriptional repressor ETV6 as a unique dependency in this tumour. Using biochemical assays and epigenomics, we show that ETV6 competes with EWS-FLI1 for binding to select DNA elements enriched for short GGAA repeat sequences. Upon inactivating ETV6, EWS-FLI1 overtakes and hyper-activates these cis-elements to promote mesenchymal differentiation, with SOX11 being a key downstream target. We show that squelching of ETV6 with a dominant-interfering peptide phenocopies these effects and suppresses Ewing sarcoma growth in vivo. These findings reveal targeting of ETV6 as a strategy for neutralizing the EWS-FLI1 oncoprotein by reprogramming of genomic occupancy.
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3
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Inhibitor of DNA binding 2 (ID2) regulates the expression of developmental genes and tumorigenesis in ewing sarcoma. Oncogene 2022; 41:2873-2884. [PMID: 35422476 PMCID: PMC9107507 DOI: 10.1038/s41388-022-02310-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 03/29/2022] [Accepted: 03/31/2022] [Indexed: 11/24/2022]
Abstract
Sarcomas are difficult to treat and the therapy, even when effective, is associated with long-term and life-threatening side effects. In addition, the treatment regimens for many sarcomas, including Ewing sarcoma, rhabdomyosarcoma, and osteosarcoma, are relatively unchanged over the past two decades, indicating a critical lack of progress. Although differentiation-based therapies are used for the treatment of some cancers, the application of this approach to sarcomas has proven challenging. Here, using a CRISPR-mediated gene knockout approach, we show that Inhibitor of DNA Binding 2 (ID2) is a critical regulator of developmental-related genes and tumor growth in vitro and in vivo in Ewing sarcoma tumors. We also identified that homoharringtonine, which is an inhibitor of protein translation and FDA-approved for the treatment of leukemia, decreases the level of the ID2 protein and significantly reduces tumor growth and prolongs mouse survival in an Ewing sarcoma xenograft model. Furthermore, in addition to targeting ID2, homoharringtonine also reduces the protein levels of ID1 and ID3, which are additional members of the ID family of proteins with well-described roles in tumorigenesis, in multiple types of cancer. Overall, these results provide insight into developmental regulation in Ewing sarcoma tumors and identify a novel, therapeutic approach to target the ID family of proteins using an FDA-approved drug.
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4
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The Landscape of Regulatory Noncoding RNAs in Ewing's Sarcoma. Biomedicines 2021; 9:biomedicines9080933. [PMID: 34440137 PMCID: PMC8391329 DOI: 10.3390/biomedicines9080933] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 07/21/2021] [Accepted: 07/27/2021] [Indexed: 02/07/2023] Open
Abstract
Ewing’s sarcoma (ES) is a pediatric sarcoma caused by a chromosomal translocation. Unlike in most cancers, the genomes of ES patients are very stable. The translocation product of the EWS-FLI1 fusion is most often the predominant genetic driver of oncogenesis, and it is pertinent to explore the role of epigenetic alterations in the onset and progression of ES. Several types of noncoding RNAs, primarily microRNAs and long noncoding RNAs, are key epigenetic regulators that have been shown to play critical roles in various cancers. The functions of these epigenetic regulators are just beginning to be appreciated in ES. Here, we performed a comprehensive literature review to identify these noncoding RNAs. We identified clinically relevant tumor suppressor microRNAs, tumor promoter microRNAs and long noncoding RNAs. We then explored the known interplay between different classes of noncoding RNAs and described the currently unmet need for expanding the noncoding RNA repertoire of ES. We concluded the review with a discussion of epigenetic regulation of ES via regulatory noncoding RNAs. These noncoding RNAs provide new avenues of exploration to develop better therapeutics and identify novel biomarkers.
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5
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Minas TZ, Surdez D, Javaheri T, Tanaka M, Howarth M, Kang HJ, Han J, Han ZY, Sax B, Kream BE, Hong SH, Çelik H, Tirode F, Tuckermann J, Toretsky JA, Kenner L, Kovar H, Lee S, Sweet-Cordero EA, Nakamura T, Moriggl R, Delattre O, Üren A. Combined experience of six independent laboratories attempting to create an Ewing sarcoma mouse model. Oncotarget 2018; 8:34141-34163. [PMID: 27191748 PMCID: PMC5470957 DOI: 10.18632/oncotarget.9388] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 05/05/2016] [Indexed: 12/17/2022] Open
Abstract
Ewing sarcoma (ES) involves a tumor-specific chromosomal translocation that produces the EWS-FLI1 protein, which is required for the growth of ES cells both in vitro and in vivo. However, an EWS-FLI1-driven transgenic mouse model is not currently available. Here, we present data from six independent laboratories seeking an alternative approach to express EWS-FLI1 in different murine tissues. We used the Runx2, Col1a2.3, Col1a3.6, Prx1, CAG, Nse, NEFL, Dermo1, P0, Sox9 and Osterix promoters to target EWS-FLI1 or Cre expression. Additional approaches included the induction of an endogenous chromosomal translocation, in utero knock-in, and the injection of Cre-expressing adenovirus to induce EWS-FLI1 expression locally in multiple lineages. Most models resulted in embryonic lethality or developmental defects. EWS-FLI1-induced apoptosis, promoter leakiness, the lack of potential cofactors, and the difficulty of expressing EWS-FLI1 in specific sites were considered the primary reasons for the failed attempts to create a transgenic mouse model of ES.
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Affiliation(s)
- Tsion Zewdu Minas
- Department of Oncology, Georgetown University Medical Center, Washington, DC, United States of America
| | - Didier Surdez
- Genetics and Biology of Cancers Unit, Institut Curie Research Center, PSL Research University, Île-de-France, Paris, France.,INSERM U830, Institut Curie Research Center, Île-de-France, Paris, France
| | | | - Miwa Tanaka
- Division of Carcinogenesis, The Cancer Institute, Japanese Foundation for Cancer Research, Tokyo, Japan
| | - Michelle Howarth
- Division of Hematology and Oncology, Department of Pediatrics, Stanford University School of Medicine, Stanford, CA, United States of America
| | - Hong-Jun Kang
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, LA, United States of America
| | - Jenny Han
- Department of Oncology, Georgetown University Medical Center, Washington, DC, United States of America
| | - Zhi-Yan Han
- Genetics and Biology of Cancers Unit, Institut Curie Research Center, PSL Research University, Île-de-France, Paris, France.,INSERM U830, Institut Curie Research Center, Île-de-France, Paris, France
| | - Barbara Sax
- Ludwig Boltzmann Institute for Cancer Research, Vienna, Austria
| | - Barbara E Kream
- Department of Medicine, and Genetics and Genome Sciences, University of Connecticut Health Science Center, Farmington, CT, United States of America
| | - Sung-Hyeok Hong
- Department of Oncology, Georgetown University Medical Center, Washington, DC, United States of America
| | - Haydar Çelik
- Department of Oncology, Georgetown University Medical Center, Washington, DC, United States of America
| | - Franck Tirode
- Genetics and Biology of Cancers Unit, Institut Curie Research Center, PSL Research University, Île-de-France, Paris, France.,INSERM U830, Institut Curie Research Center, Île-de-France, Paris, France
| | - Jan Tuckermann
- Institute of Comparative Molecular Endocrinology (CME), University of Ulm, Ulm, Germany
| | - Jeffrey A Toretsky
- Department of Oncology, Georgetown University Medical Center, Washington, DC, United States of America
| | - Lukas Kenner
- Ludwig Boltzmann Institute for Cancer Research, Vienna, Austria.,Clinical Institute of Pathology, Medical University of Vienna, Vienna, Austria.,Department of Pathology of Laboratory Animals (UPLA), University of Veterinary Medicine, Vienna, Austria
| | - Heinrich Kovar
- Department of Pediatrics, Medical University of Vienna, Vienna, Austria.,Children´s Cancer Research Institute, St. Anna Kinderkrebsforschung, Vienna, Austria
| | - Sean Lee
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, LA, United States of America
| | - E Alejandro Sweet-Cordero
- Division of Hematology and Oncology, Department of Pediatrics, Stanford University School of Medicine, Stanford, CA, United States of America
| | - Takuro Nakamura
- Division of Carcinogenesis, The Cancer Institute, Japanese Foundation for Cancer Research, Tokyo, Japan
| | - Richard Moriggl
- Ludwig Boltzmann Institute for Cancer Research, Vienna, Austria.,Institute of Animal Breeding and Genetics, University of Veterinary Medicine, Vienna, Austria.,Medical University of Vienna, Vienna, Austria
| | - Olivier Delattre
- Genetics and Biology of Cancers Unit, Institut Curie Research Center, PSL Research University, Île-de-France, Paris, France.,INSERM U830, Institut Curie Research Center, Île-de-France, Paris, France.,Unité de génétique somatique, Institut Curie, Île-de-France, Paris, France
| | - Aykut Üren
- Department of Oncology, Georgetown University Medical Center, Washington, DC, United States of America
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6
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Evola FR, Costarella L, Pavone V, Caff G, Cannavò L, Sessa A, Avondo S, Sessa G. Biomarkers of Osteosarcoma, Chondrosarcoma, and Ewing Sarcoma. Front Pharmacol 2017; 8:150. [PMID: 28439237 PMCID: PMC5383728 DOI: 10.3389/fphar.2017.00150] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2016] [Accepted: 03/09/2017] [Indexed: 02/03/2023] Open
Abstract
Osteosarcoma is the most frequent malignant bone neoplasm, followed by chondrosarcoma and Ewing sarcoma. The diagnosis of bone neoplasms is generally made through histological evaluation of a biopsy. Clinical and radiological features are also important in aiding diagnosis and to complete the staging of bone cancer. In addition to these, there are several non-specific serological or specific molecular markers for bone neoplasms. In bone tumors, molecular markers increase the accuracy of the diagnosis and assist in subtyping bone tumors. Here, we review these markers and discuss their role in the diagnosis and prognosis of the three most frequent malignant bone neoplasms, namely osteosarcoma, chondrosarcoma, and Ewing sarcoma.
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Affiliation(s)
- Francesco R Evola
- Clinica Ortopedica, Dipartimento di Chirurgia, Azienda Ospedaliera-Universitaria Policlinico Vittorio Emanuele di CataniaCatania, Italy
| | - Luciano Costarella
- Clinica Ortopedica, Dipartimento di Chirurgia, Azienda Ospedaliera-Universitaria Policlinico Vittorio Emanuele di CataniaCatania, Italy
| | - Vito Pavone
- Clinica Ortopedica, Dipartimento di Chirurgia, Azienda Ospedaliera-Universitaria Policlinico Vittorio Emanuele di CataniaCatania, Italy
| | - Giuseppe Caff
- Clinica Ortopedica, Dipartimento di Chirurgia, Azienda Ospedaliera-Universitaria Policlinico Vittorio Emanuele di CataniaCatania, Italy
| | - Luca Cannavò
- Clinica Ortopedica, Dipartimento di Chirurgia, Azienda Ospedaliera-Universitaria Policlinico Vittorio Emanuele di CataniaCatania, Italy
| | - Andrea Sessa
- Clinica Ortopedica, Dipartimento di Chirurgia, Azienda Ospedaliera-Universitaria Policlinico Vittorio Emanuele di CataniaCatania, Italy
| | - Sergio Avondo
- Clinica Ortopedica, Dipartimento di Chirurgia, Azienda Ospedaliera-Universitaria Policlinico Vittorio Emanuele di CataniaCatania, Italy
| | - Giuseppe Sessa
- Clinica Ortopedica, Dipartimento di Chirurgia, Azienda Ospedaliera-Universitaria Policlinico Vittorio Emanuele di CataniaCatania, Italy
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7
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8
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Villasante A, Marturano-Kruik A, Ambati SR, Liu Z, Godier-Furnemont A, Parsa H, Lee BW, Moore MA, Vunjak-Novakovic G. Recapitulating the Size and Cargo of Tumor Exosomes in a Tissue-Engineered Model. Theranostics 2016; 6:1119-30. [PMID: 27279906 PMCID: PMC4893640 DOI: 10.7150/thno.13944] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Accepted: 12/20/2015] [Indexed: 12/20/2022] Open
Abstract
There is a growing interest in the pivotal role of exosomes in cancer and in their use as biomarkers. However, despite the importance of the microenvironment for cancer initiation and progression, monolayer cultures of tumor cells still represent the main in vitro source of exosomes. As a result, their environmental regulation remains largely unknown. Here, we report a three-dimensional tumor model for studying exosomes, using Ewing's sarcoma type 1 as a clinically relevant example. The bioengineered model was designed based on the hypothesis that the 3-dimensionality, composition and stiffness of the tumor matrix are the critical determinants of the size and cargo of exosomes released by the cancer cells. We analyzed the effects of the tumor microenvironment on exosomes, and the effects of exosomes on the non-cancer cells from the bone niche. Exosomes from the tissue-engineered tumor had similar size distribution as those in the patients' plasma, and were markedly smaller than those in monolayer cultures. Bioengineered tumors and the patients' plasma contained high levels of the Polycomb histone methyltransferase EZH2 mRNA relatively to their monolayer counterparts. Notably, EZH2 mRNA, a potential tumor biomarker detectable in blood plasma, could be transferred to the surrounding mesenchymal stem cells. This study provides the first evidence that an in vitro culture environment can recapitulate some properties of tumor exosomes.
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9
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Gordon DJ, Motwani M, Pellman D. Modeling the initiation of Ewing sarcoma tumorigenesis in differentiating human embryonic stem cells. Oncogene 2015; 35:3092-102. [PMID: 26455317 PMCID: PMC4829493 DOI: 10.1038/onc.2015.368] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Revised: 07/12/2015] [Accepted: 08/31/2015] [Indexed: 01/08/2023]
Abstract
Oncogenic transformation in Ewing sarcoma tumors is driven by the fusion oncogene EWS-FLI1. However, despite the well-established role of EWS-FLI1 in tumor initiation, the development of models of Ewing sarcoma in human cells with defined genetic elements has been challenging. Here, we report a novel approach to model the initiation of Ewing sarcoma tumorigenesis that exploits the developmental and pluripotent potential of human embryonic stem cells. The inducible expression of EWS-FLI1 in embryoid bodies, or collections of differentiating stem cells, generates cells with properties of Ewing sarcoma tumors, including characteristics of transformation. These cell lines exhibit anchorage-independent growth, a lack of contact inhibition and a strong Ewing sarcoma gene expression signature. Furthermore, these cells also demonstrate a requirement for the persistent expression of EWS-FLI1 for cell survival and growth, which is a hallmark Ewing sarcoma tumors.
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Affiliation(s)
- D J Gordon
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - M Motwani
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - D Pellman
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA, USA.,Department of Cell Biology, Harvard Medical School, Boston, MA, USA.,Howard Hughes Medical Institute, Boston, MA, USA
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10
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Erkizan HV, Schneider JA, Sajwan K, Graham GT, Griffin B, Chasovskikh S, Youbi SE, Kallarakal A, Chruszcz M, Padmanabhan R, Casey JL, Üren A, Toretsky JA. RNA helicase A activity is inhibited by oncogenic transcription factor EWS-FLI1. Nucleic Acids Res 2015; 43:1069-80. [PMID: 25564528 PMCID: PMC4333382 DOI: 10.1093/nar/gku1328] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
RNA helicases impact RNA structure and metabolism from transcription through translation, in part through protein interactions with transcription factors. However, there is limited knowledge on the role of transcription factor influence upon helicase activity. RNA helicase A (RHA) is a DExH-box RNA helicase that plays multiple roles in cellular biology, some functions requiring its activity as a helicase while others as a protein scaffold. The oncogenic transcription factor EWS-FLI1 requires RHA to enable Ewing sarcoma (ES) oncogenesis and growth; a small molecule, YK-4-279 disrupts this complex in cells. Our current study investigates the effect of EWS-FLI1 upon RHA helicase activity. We found that EWS-FLI1 reduces RHA helicase activity in a dose-dependent manner without affecting intrinsic ATPase activity; however, the RHA kinetics indicated a complex model. Using separated enantiomers, only (S)-YK-4-279 reverses the EWS-FLI1 inhibition of RHA helicase activity. We report a novel RNA binding property of EWS-FLI1 leading us to discover that YK-4-279 inhibition of RHA binding to EWS-FLI1 altered the RNA binding profile of both proteins. We conclude that EWS-FLI1 modulates RHA helicase activity causing changes in overall transcriptome processing. These findings could lead to both enhanced understanding of oncogenesis and provide targets for therapy.
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Affiliation(s)
- Hayriye Verda Erkizan
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, 3970 Reservoir Road NW, New Research Building E316, Washington, DC 20007, USA
| | - Jeffrey A Schneider
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, 3970 Reservoir Road NW, New Research Building E316, Washington, DC 20007, USA
| | - Kamal Sajwan
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, 3970 Reservoir Road NW, New Research Building E316, Washington, DC 20007, USA
| | - Garrett T Graham
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, 3970 Reservoir Road NW, New Research Building E316, Washington, DC 20007, USA
| | - Brittany Griffin
- Department of Microbiology and Immunology, Georgetown University Medical Center, SW 309 Med-Dent, Washington, DC 20007, USA
| | - Sergey Chasovskikh
- Department of Radiation Medicine, Georgetown University Medical Center, 3970 Reservoir Road NW, New Research Building E220, Washington, DC 20007, USA
| | - Sarah E Youbi
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, 3970 Reservoir Road NW, New Research Building E316, Washington, DC 20007, USA
| | - Abraham Kallarakal
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, 3970 Reservoir Road NW, New Research Building E316, Washington, DC 20007, USA
| | - Maksymilian Chruszcz
- Department of Chemistry and Biochemistry, University of South Carolina, 631 Sumter Street, Columbia, SC 29208, USA
| | - Radhakrishnan Padmanabhan
- Department of Microbiology and Immunology, Georgetown University Medical Center, SW 309 Med-Dent, Washington, DC 20007, USA
| | - John L Casey
- Department of Microbiology and Immunology, Georgetown University Medical Center, SW 309 Med-Dent, Washington, DC 20007, USA
| | - Aykut Üren
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, 3970 Reservoir Road NW, New Research Building E316, Washington, DC 20007, USA
| | - Jeffrey A Toretsky
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, 3970 Reservoir Road NW, New Research Building E316, Washington, DC 20007, USA
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11
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Malkan AD, Loh A, Bahrami A, Navid F, Coleman J, Green DM, Davidoff AM, Sandoval JA. An approach to renal masses in pediatrics. Pediatrics 2015; 135:142-58. [PMID: 25452658 DOI: 10.1542/peds.2014-1011] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Renal masses in children may be discovered during routine clinical examination or incidentally during the course of diagnostic or therapeutic procedures for other causes. Renal cancers are rare in the pediatric population and include a spectrum of pathologies that may challenge the clinician in choosing the optimal treatment. Correct identification of the lesion may be difficult, and the appropriate surgical procedure is paramount for lesions suspected to be malignant. The purpose of this article is to provide a comprehensive overview regarding the spectrum of renal tumors in the pediatric population, both benign and malignant, and their surgical management.
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Affiliation(s)
| | | | | | - Fariba Navid
- Oncology, Department of Pediatrics, College of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee
| | | | - Daniel M Green
- Epidemiology and Cancer Control, St. Jude Children's Research Hospital, Memphis, Tennessee; and
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12
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Kovar H. Blocking the road, stopping the engine or killing the driver? Advances in targeting EWS/FLI-1 fusion in Ewing sarcoma as novel therapy. Expert Opin Ther Targets 2014; 18:1315-28. [PMID: 25162919 DOI: 10.1517/14728222.2014.947963] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
INTRODUCTION Ewing sarcoma (ES) represents the paradigm of an aberrant E-twenty-six (ETS) oncogene-driven cancer. It is characterized by specific rearrangements of one of five alternative ETS family member genes with EWSR1. There is experimental evidence that the resulting fusion proteins act as aberrant transcription factors driving ES pathogenesis. The transcriptional gene regulatory network driven by EWS-ETS proteins provides the oncogenic engine to the tumor. Therefore, EWS-ETS and their downstream machinery are considered ideal tumor-specific therapeutic targets. AREAS COVERED This review critically discusses the literature on the development of EWS-ETS-directed ES targeting strategies considering current knowledge of EWS-ETS biology and cellular context. It focuses on determinants of EWS-FLI1 function with an emphasis on interactions with chromatin structure. We speculate about the relevance of poorly investigated aspects in ES research such as chromatin remodeling and DNA damage repair for the development of targeted therapies. EXPERT OPINION This review questions the specificity of signature-based screening approaches to the identification of EWS-FLI1-targeted compounds. It challenges the view that targeting the downstream gene regulatory network carries potential for therapeutic breakthroughs because of resistance-inducing network rewiring. Instead, we propose to combine targeting of the fusion protein with epigenetic therapy as a future treatment strategy in ES.
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Affiliation(s)
- Heinrich Kovar
- Children´s Cancer Research Institute, St. Anna Kinderkrebsforschung, and Medical University Vienna, Department of Pediatrics , Zimmermannplatz 10, A1090 Vienna , Austria +43 1 40470 4092 ; +43 1 40470 64092 ;
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13
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Anderson JL, Titz B, Akiyama R, Komisopoulou E, Park A, Tap WD, Graeber TG, Denny CT. Phosphoproteomic profiling reveals IL6-mediated paracrine signaling within the Ewing sarcoma family of tumors. Mol Cancer Res 2014; 12:1740-54. [PMID: 25092916 DOI: 10.1158/1541-7786.mcr-14-0159] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
UNLABELLED Members of the Ewing sarcoma family of tumors (ESFT) contain tumor-associated translocations that give rise to oncogenic transcription factors, most commonly EWS/FLI1. EWS/FLI1 plays a dominant role in tumor progression by modulating the expression of hundreds of target genes. Here, the impact of EWS/FLI1 inhibition, by RNAi-mediated knockdown, on cellular signaling was investigated using mass spectrometry-based phosphoproteomics to quantify global changes in phosphorylation. This unbiased approach identified hundreds of unique phosphopeptides enriched in processes such as regulation of cell cycle and cytoskeleton organization. In particular, phosphotyrosine profiling revealed a large upregulation of STAT3 phosphorylation upon EWS/FLI1 knockdown. However, single-cell analysis demonstrated that this was not a cell-autonomous effect of EWS/FLI1 deficiency, but rather a signaling effect occurring in cells in which knockdown does not occur. Conditioned media from knockdown cells were sufficient to induce STAT3 phosphorylation in control cells, verifying the presence of a soluble factor that can activate STAT3. Cytokine analysis and ligand/receptor inhibition experiments determined that this activation occurred, in part, through an IL6-dependent mechanism. Taken together, the data support a model in which EWS/FLI1 deficiency results in the secretion of soluble factors, such as IL6, which activate STAT signaling in bystander cells that maintain EWS/FLI1 expression. Furthermore, these soluble factors were shown to protect against apoptosis. IMPLICATIONS EWS/FLI1 inhibition results in a novel adaptive response and suggests that targeting the IL6/STAT3 signaling pathway may increase the efficacy of ESFT therapies.
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Affiliation(s)
- Jennifer L Anderson
- Molecular Biology Institute, University of California, Los Angeles, Los Angeles, California. Division of Hematology/Oncology, Department of Pediatrics, Gwynne Hazen Cherry Memorial Laboratories, University of California, Los Angeles, Los Angeles, California
| | - Björn Titz
- Crump Institute for Molecular Imaging, University of California, Los Angeles, Los Angeles, California. Jonsson Comprehensive Cancer Center, University of California, Los Angeles, Los Angeles, California. Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California
| | - Ryan Akiyama
- Division of Hematology/Oncology, Department of Pediatrics, Gwynne Hazen Cherry Memorial Laboratories, University of California, Los Angeles, Los Angeles, California
| | - Evangelia Komisopoulou
- Crump Institute for Molecular Imaging, University of California, Los Angeles, Los Angeles, California. Jonsson Comprehensive Cancer Center, University of California, Los Angeles, Los Angeles, California. Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California
| | - Ann Park
- Division of Hematology/Oncology, Department of Pediatrics, Gwynne Hazen Cherry Memorial Laboratories, University of California, Los Angeles, Los Angeles, California
| | - William D Tap
- Sarcoma Medical Oncology Service, Division of Solid Tumors, Department of Medicine, Memorial Sloan Kettering Cancer Center and Department of Medicine, Weill Cornell Medical College, New York, New York
| | - Thomas G Graeber
- Crump Institute for Molecular Imaging, University of California, Los Angeles, Los Angeles, California. Jonsson Comprehensive Cancer Center, University of California, Los Angeles, Los Angeles, California. Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California. California NanoSystems Institute, University of California, Los Angeles, Los Angeles, California. UCLA Metabolomics Center, University of California, Los Angeles, Los Angeles, California
| | - Christopher T Denny
- Molecular Biology Institute, University of California, Los Angeles, Los Angeles, California. Division of Hematology/Oncology, Department of Pediatrics, Gwynne Hazen Cherry Memorial Laboratories, University of California, Los Angeles, Los Angeles, California. Jonsson Comprehensive Cancer Center, University of California, Los Angeles, Los Angeles, California. California NanoSystems Institute, University of California, Los Angeles, Los Angeles, California.
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14
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Rainusso N, Wang LL, Yustein JT. The adolescent and young adult with cancer: state of the art -- bone tumors. Curr Oncol Rep 2013; 15:296-307. [PMID: 23690089 DOI: 10.1007/s11912-013-0321-9] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Primary malignant bone tumors in the pediatric to young adult populations are relatively uncommon and account for about 6 % of all cancers in those less than 20 years old [1] and 3 % of all cancers in adolescents and young adults (AYA) within the age range of 15 to 29 years [2]. Osteosarcoma (OS) and Ewing's sarcoma (ES) comprise the majority of malignant bone tumors. The approach to treatment for both tumors consists of local control measures (surgery or radiation) as well as systemic therapy with high-dose chemotherapy. Despite earlier advances, there have been no substantial improvements in outcomes over the past several decades, particularly for patients with metastatic disease. This review summarizes the major advances in the treatment of OS and ES and the standard therapies available today, current active clinical trials, and areas of investigation into molecularly targeted therapies.
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Affiliation(s)
- Nino Rainusso
- Department of Pediatrics, Section of Hematology-Oncology, Baylor College of Medicine, Texas Children's Cancer and Hematology Centers, 6701 Fannin Street, Suite 1510.00, Houston, TX 77030, USA.
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Tomlins SA, Palanisamy N, Brenner JC, Stall JN, Siddiqui J, Thomas DG, Lucas DR, Chinnaiyan AM, Kunju LP. Usefulness of a monoclonal ERG/FLI1 antibody for immunohistochemical discrimination of Ewing family tumors. Am J Clin Pathol 2013; 139:771-9. [PMID: 23690120 DOI: 10.1309/ajcpn4l1bmrqpeit] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Ewing family tumors (EFTs) and prostate carcinomas are characterized by rearrangement of ETS genes, most commonly FLI1 (EFTs) and ERG (prostate carcinomas). Previously, we characterized an antibody against ERG (EPR3864) for detecting ERG-rearranged prostate carcinoma. Because EPR3864 also cross-reacts with FLI1, we evaluated the usefulness of EPR3864 for discriminating EFTs from other small round blue cell tumors (SRBCTs) with immunohistochemistry. Of 57 evaluable EFTs, 47 (82%) demonstrated at least moderate, diffuse, nuclear ERG/FLI1 staining (including 89% and 100% of cases with confirmed EWSR1:FLI1 and EWSR1:ERG fusions, respectively), of which 1, 3, and 43 showed negative, cytoplasmic, or membranous CD99 staining, respectively. Among other SRBCTs (61 cases, 7 types), at least moderate, diffuse, nuclear EPR3864 staining was seen in all precursor B-lymphoblastic lymphomas/leukemias and subsets of Burkitt lymphomas (10%) and synovial sarcomas (45%). In summary, EPR3864 may be useful in detecting EWSR1:FLI1 and EWSR1:ERG rearranged EFTs in addition to prostate carcinomas.
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Monument MJ, Bernthal NM, Randall RL. Salient features of mesenchymal stem cells-implications for Ewing sarcoma modeling. Front Oncol 2013; 3:24. [PMID: 23443465 PMCID: PMC3580960 DOI: 10.3389/fonc.2013.00024] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2013] [Accepted: 01/30/2013] [Indexed: 12/19/2022] Open
Abstract
Despite a heightened appreciation of the many defining molecular aberrations in Ewing sarcoma, the cooperative genetic environment and permissive cell of origin essential for EWS/ETS-mediated oncogenesis remain elusive. Consequently, inducible animal and in vitro models of Ewing sarcoma from a native cellular context are unable to fully recapitulate malignant transformation. Despite these shortcomings, human, and murine mesenchymal stem cells (MSCs) are the closest working in vitro systems available. MSCs are tolerant of ectopic EWS/FLI expression, which is accompanied by a molecular signature most similar to Ewing sarcoma. Whether MSCs are the elusive cell of origin or simply a tolerant platform of the EWS/FLI transcriptome, these cells have become an excellent molecular tool to investigate and manipulate oncogenesis in Ewing sarcoma. Our understanding of the biological complexity and heterogeneity of human MSCs (hMSCs) has increased substantially over time and as such, appreciation and utilization of these salient complexities may greatly enhance the efficient use of these cells as surrogate models for Ewing sarcoma tumorigenesis.
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Affiliation(s)
- Michael J Monument
- Sarcoma Services, Department of Orthopaedic Surgery, Huntsman Cancer Institute, University of Utah Salt Lake City, UT, USA
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Mosakhani N, Guled M, Leen G, Calabuig-Fariñas S, Niini T, Machado I, Savola S, Scotlandi K, López-Guerrero JA, Llombart-Bosch A, Knuutila S. An integrated analysis of miRNA and gene copy numbers in xenografts of Ewing's sarcoma. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2012; 31:24. [PMID: 22429812 PMCID: PMC3338077 DOI: 10.1186/1756-9966-31-24] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Accepted: 03/20/2012] [Indexed: 12/21/2022]
Abstract
Background Xenografts have been shown to provide a suitable source of tumor tissue for molecular analysis in the absence of primary tumor material. We utilized ES xenograft series for integrated microarray analyses to identify novel biomarkers. Method Microarray technology (array comparative genomic hybridization (aCGH) and micro RNA arrays) was used to screen and identify copy number changes and differentially expressed miRNAs of 34 and 14 passages, respectively. Incubated cells used for xenografting (Passage 0) were considered to represent the primary tumor. Four important differentially expressed miRNAs (miR-31, miR-31*, miR-145, miR-106) were selected for further validation by real time polymerase chain reaction (RT-PCR). Integrated analysis of aCGH and miRNA data was performed on 14 xenograft passages by bioinformatic methods. Results The most frequent losses and gains of DNA copy number were detected at 9p21.3, 16q and at 8, 15, 17q21.32-qter, 1q21.1-qter, respectively. The presence of these alterations was consistent in all tumor passages. aCGH profiles of xenograft passages of each series resembled their corresponding primary tumors (passage 0). MiR-21, miR-31, miR-31*, miR-106b, miR-145, miR-150*, miR-371-5p, miR-557 and miR-598 showed recurrently altered expression. These miRNAS were predicted to regulate many ES-associated genes, such as genes of the IGF1 pathway, EWSR1, FLI1 and their fusion gene (EWS-FLI1). Twenty differentially expressed miRNAs were pinpointed in regions carrying altered copy numbers. Conclusion In the present study, ES xenografts were successfully applied for integrated microarray analyses. Our findings showed expression changes of miRNAs that were predicted to regulate many ES associated genes, such as IGF1 pathway genes, FLI1, EWSR1, and the EWS-FLI1 fusion genes.
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Affiliation(s)
- Neda Mosakhani
- Department of Pathology, Haartman Institute and HUSLAB, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland
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France KA, Anderson JL, Park A, Denny CT. Oncogenic fusion protein EWS/FLI1 down-regulates gene expression by both transcriptional and posttranscriptional mechanisms. J Biol Chem 2011; 286:22750-7. [PMID: 21531709 DOI: 10.1074/jbc.m111.225433] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Ewing family tumors are characterized by a translocation between the RNA binding protein EWS and one of five ETS transcription factors, most commonly FLI1. The fusion protein produced by the translocation has been thought to act as an aberrant transcription factor, leading to changes in gene expression and cellular transformation. In this study, we investigated the specific processes EWS/FLI1 utilizes to alter gene expression. Using both heterologous NIH 3T3 and human Ewing Family Tumor cell lines, we have demonstrated by quantitative pre-mRNA analysis that EWS/FLI1 repressed the expression of previously validated direct target genes at the level of transcript synthesis. ChIP experiments showed that EWS/FLI1 decreases the amount of Pol II at the promoter of down-regulated genes in both murine and human model systems. However, in down-regulated target genes, there was a significant disparity between the modulation of cognate mRNA and pre-mRNAs, suggesting that these genes could also be regulated at a posttranscriptional level. Confirming this, we found that EWS/FLI1 decreased the transcript half-life of insulin-like growth factor binding protein 3, a down-regulated direct target gene in human tumor-derived Ewing's sarcoma cell lines. Additionally, we have shown through reexpression experiments that full EWS/FLI1-mediated transcriptional repression requires intact EWS and ETS domains. Together these data demonstrate that EWS/FLI1 can dictate steady-state target gene expression by modulating both transcript synthesis and degradation.
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Affiliation(s)
- Kelly A France
- Molecular Biology Institute, University of California, Los Angeles, California 90095, USA
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Cell Cycle Deregulation in Ewing's Sarcoma Pathogenesis. Sarcoma 2010; 2011:598704. [PMID: 21052502 PMCID: PMC2968116 DOI: 10.1155/2011/598704] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2010] [Accepted: 10/07/2010] [Indexed: 12/18/2022] Open
Abstract
Ewing's sarcoma is a highly aggressive pediatric tumor of bone that usually contains the characteristic chromosomal translocation t(11;22)(q24;q12). This translocation encodes the oncogenic fusion protein EWS/FLI, which acts as an aberrant transcription factor to deregulate target genes necessary for oncogenesis. One key feature of oncogenic transformation is dysregulation of cell cycle control. It is therefore likely that EWS/FLI and other cooperating mutations in Ewing's sarcoma modulate the cell cycle to facilitate tumorigenesis. This paper will summarize current published data associated with deregulation of the cell cycle in Ewing's sarcoma and highlight important questions that remain to be answered.
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Mesenchymal Stem Cells and the Origin of Ewing's Sarcoma. Sarcoma 2010; 2011. [PMID: 20953407 PMCID: PMC2952797 DOI: 10.1155/2011/276463] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2010] [Accepted: 09/06/2010] [Indexed: 12/17/2022] Open
Abstract
The origin of Ewing's sarcoma is a subject of much debate. Once thought to be derived from primitive neuroectodermal cells, many now believe it to arise from a mesenchymal stem cell (MSC). Expression of the EWS-FLI1 fusion gene in MSCs changes cell morphology to resemble Ewing's sarcoma and induces expression of neuroectodermal markers. In murine cells, transformation to sarcomas can occur. In knockdown experiments, Ewing's sarcoma cells develop characteristics of MSCs and the ability to differentiate into mesodermal lineages. However, it cannot be concluded that MSCs are the cell of origin. The concept of an MSC still needs to be rigorously defined, and there may be different subpopulations of mesenchymal pluripotential cells. Furthermore, EWS-FLI1 by itself does not transform human cells, and cooperating mutations appear to be necessary. Therefore, while it is possible that Ewing's sarcoma may originate from a primitive mesenchymal cell, the idea needs to be refined further.
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Aryee DNT, Niedan S, Kauer M, Schwentner R, Bennani-Baiti IM, Ban J, Muehlbacher K, Kreppel M, Walker RL, Meltzer P, Poremba C, Kofler R, Kovar H. Hypoxia modulates EWS-FLI1 transcriptional signature and enhances the malignant properties of Ewing's sarcoma cells in vitro. Cancer Res 2010; 70:4015-23. [PMID: 20442286 DOI: 10.1158/0008-5472.can-09-4333] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Hypoxia is an important condition in the tumor cell microenvironment and approximately 1% to 1.5% of the genome is transcriptionally responsive to hypoxia with hypoxia-inducible factor-1 (HIF-1) as a major mediator of transcriptional activation. Tumor hypoxia is associated with a more aggressive phenotype of many cancers in adults, but data on pediatric tumors are scarce. Because, by immunohistochemistry, HIF-1alpha expression was readily detectable in 18 of 28 primary Ewing's sarcoma family tumors (ESFT), a group of highly malignant bone-associated tumors in children and young adults, we studied the effect of hypoxia on ESFT cell lines in vitro. Intriguingly, we found that EWS-FLI1 protein expression, which characterizes ESFT, is upregulated by hypoxia in a HIF-1alpha-dependent manner. Hypoxia modulated the EWS-FLI1 transcriptional signature relative to normoxic conditions. Both synergistic as well as antagonistic transcriptional effects of EWS-FLI1 and of hypoxia were observed. Consistent with alterations in the expression of metastasis-related genes, hypoxia stimulated the invasiveness and soft agar colony formation of ESFT cells in vitro. Our data represent the first transcriptome analysis of hypoxic ESFT cells and identify hypoxia as an important microenvironmental factor modulating EWS-FLI1 expression and target gene activity with far-reaching consequences for the malignant properties of ESFT.
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Affiliation(s)
- Dave N T Aryee
- Children's Cancer Research Institute, St. Anna Kinderkrebsforschung, Vienna, Austria.
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Ikeda AK, Judelson DR, Federman N, Glaser KB, Landaw EM, Denny CT, Sakamoto KM. ABT-869 inhibits the proliferation of Ewing Sarcoma cells and suppresses platelet-derived growth factor receptor beta and c-KIT signaling pathways. Mol Cancer Ther 2010; 9:653-60. [PMID: 20197394 DOI: 10.1158/1535-7163.mct-09-0812] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The Ewing Sarcoma (EWS) family of tumors is one of the most common tumors diagnosed in children and adolescents and is characterized by a translocation involving the EWS gene. Despite advances in chemotherapy, the prognosis of metastatic EWS is poor with an overall survival of <30% after 5 years. EWS tumor cells express the receptor tyrosine kinases, platelet-derived growth factor receptor (PDGFR) and c-KIT. ABT-869 is a multitargeted small-molecule inhibitor that targets Fms-like tyrosine kinase-3, c-KIT, vascular endothelial growth receptors, and PDGFRs. To determine the potential therapeutic benefit of ABT-869 in EWS cells, we examined the effects of ABT-869 on EWS cell lines and xenograft mouse models. ABT-869 inhibited the proliferation of two EWS cell lines, A4573 and TC71, at an IC(50) of 1.25 and 2 mumol/L after 72 h of treatment, respectively. The phosphorylation of PDGFRbeta, c-KIT, and extracellular signal-regulated kinases was also inhibited. To examine the effects of ABT-869 in vivo, the drug was given to mice injected with EWS cells. We observed inhibition of growth of EWS tumor cells in a xenograft mouse model and prolonged survival in a metastatic mouse model of EWS. Therefore, our in vitro and in vivo studies show that ABT-869 inhibits proliferation of EWS cells through inhibition of PDGFRbeta and c-KIT pathways.
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Affiliation(s)
- Alan K Ikeda
- Division of Hematology/Oncology, Department of Pediatrics, Gwynne Hazen Cherry Memorial Laboratories, Jonsson Comprehensive Cancer Center, David Geffen School of Medicine at the University of California at Los Angeles, Los Angeles, California 90095-1752, USA
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Kauer M, Ban J, Kofler R, Walker B, Davis S, Meltzer P, Kovar H. A molecular function map of Ewing's sarcoma. PLoS One 2009; 4:e5415. [PMID: 19404404 PMCID: PMC2671847 DOI: 10.1371/journal.pone.0005415] [Citation(s) in RCA: 139] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2009] [Accepted: 03/27/2009] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND EWS-FLI1 is a chimeric ETS transcription factor that is, due to a chromosomal rearrangement, specifically expressed in Ewing's sarcoma family tumors (ESFT) and is thought to initiate the development of the disease. Previous genomic profiling experiments have identified EWS-FLI1-regulated genes and genes that discriminate ESFT from other sarcomas, but so far a comprehensive analysis of EWS-FLI1-dependent molecular functions characterizing this aggressive cancer is lacking. METHODOLOGY/PRINCIPAL FINDINGS In this study, a molecular function map of ESFT was constructed based on an integrative analysis of gene expression profiling experiments following EWS-FLI1 knockdown in a panel of five ESFT cell lines, and on gene expression data from the same platform of 59 primary ESFT. Out of 80 normal tissues tested, mesenchymal progenitor cells (MPC) were found to fit the hypothesis that EWS-FLI1 is the driving transcriptional force in ESFT best and were therefore used as the reference tissue for the construction of the molecular function map. The interrelations of molecular pathways were visualized by measuring the similarity among annotated gene functions by gene sharing. The molecular function map highlighted distinct clusters of activities for EWS-FLI1 regulated genes in ESFT and revealed a striking difference between EWS-FLI1 up- and down-regulated genes: EWS-FLI1 induced genes mainly belong to cell cycle regulation, proliferation, and response to DNA damage, while repressed genes were associated with differentiation and cell communication. CONCLUSIONS/SIGNIFICANCE This study revealed that EWS-FLI1 combines by distinct molecular mechanisms two important functions of cellular transformation in one protein, growth promotion and differentiation blockage. By taking MPC as a reference tissue, a significant EWS-FLI1 signature was discovered in ESFT that only partially overlapped with previously published EWS-FLI1-dependent gene expression patterns, identifying a series of novel targets for the chimeric protein in ESFT. Our results may guide target selection for future ESFT specific therapies.
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Affiliation(s)
- Maximilian Kauer
- Children's Cancer Research Institute, St. Anna Kinderkrebsforschung, Vienna, Austria
| | - Jozef Ban
- Children's Cancer Research Institute, St. Anna Kinderkrebsforschung, Vienna, Austria
| | - Reinhard Kofler
- Biocenter, Division of Molecular Pathophysiology, Medical University Innsbruck, Innsbruck, Austria
| | - Bob Walker
- Genetics Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Sean Davis
- Genetics Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Paul Meltzer
- Genetics Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Heinrich Kovar
- Children's Cancer Research Institute, St. Anna Kinderkrebsforschung, Vienna, Austria
- * E-mail:
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