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Harrison EN, Jay AN, Kent MR, Sukienik TP, LaVigne CA, Kendall GC. Engineering an fgfr4 knockout zebrafish to study its role in development and disease. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.08.593184. [PMID: 38766056 PMCID: PMC11100669 DOI: 10.1101/2024.05.08.593184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Fibroblast growth factor receptor 4 (FGFR4) has a role in many biological processes, including lipid metabolism, tissue repair, and vertebrate development. In recent years, FGFR4 overexpression and activating mutations have been associated with numerous adult and pediatric cancers. As such, FGFR4 presents an opportunity for therapeutic targeting which is being pursued in clinical trials. To understand the role of FGFR4 signaling in disease and development, we generated and characterized three alleles of fgfr4 knockout zebrafish strains using CRISPR/Cas9. To generate fgfr4 knockout crispants, we injected single-cell wildtype zebrafish embryos with fgfr4 targeting guide RNA and Cas9 proteins, identified adult founders, and outcrossed to wildtype zebrafish to create an F1 generation. The generated mutations introduce a stop codon within the second Ig-like domain of Fgfr4, resulting in a truncated 215, 223, or 228 amino acid Fgfr4 protein compared to 922 amino acids in the full-length protein. All mutant strains exhibited significantly decreased fgfr4 mRNA expression during development, providing evidence for successful knockout of fgfr4 in mutant zebrafish. We found that, consistent with other Fgfr4 knockout animal models, the fgfr4 mutant fish developed normally; however, homozygous fgfr4 mutant zebrafish were significantly smaller than wildtype fish at three months post fertilization. These fgfr4 knockout zebrafish lines are a valuable tool to study the role of FGFR4 in vertebrate development and its viability as a potential therapeutic target in pediatric and adult cancers, as well as other diseases.
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2
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Brown LM, Ekert PG, Fleuren EDG. Biological and clinical implications of FGFR aberrations in paediatric and young adult cancers. Oncogene 2023:10.1038/s41388-023-02705-7. [PMID: 37130917 DOI: 10.1038/s41388-023-02705-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 04/16/2023] [Accepted: 04/20/2023] [Indexed: 05/04/2023]
Abstract
Rare but recurrent mutations in the fibroblast growth factor receptor (FGFR) pathways, most commonly in one of the four FGFR receptor tyrosine kinase genes, can potentially be targeted with broad-spectrum multi-kinase or FGFR selective inhibitors. The complete spectrum of these mutations in paediatric cancers is emerging as precision medicine programs perform comprehensive sequencing of individual tumours. Identification of patients most likely to benefit from FGFR inhibition currently rests on identifying activating FGFR mutations, gene fusions, or gene amplification events. However, the expanding use of transcriptome sequencing (RNAseq) has identified that many tumours overexpress FGFRs, in the absence of any genomic aberration. The challenge now presented is to determine when this indicates true FGFR oncogenic activity. Under-appreciated mechanisms of FGFR pathway activation, including alternate FGFR transcript expression and concomitant FGFR and FGF ligand expression, may mark those tumours where FGFR overexpression is indicative of a dependence on FGFR signalling. In this review, we provide a comprehensive and mechanistic overview of FGFR pathway aberrations and their functional consequences in paediatric cancer. We explore how FGFR over expression might be associated with true receptor activation. Further, we discuss the therapeutic implications of these aberrations in the paediatric setting and outline current and emerging therapeutic strategies to treat paediatric patients with FGFR-driven cancers.
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Affiliation(s)
- Lauren M Brown
- Children's Cancer Institute, Lowy Cancer Research Centre, UNSW Sydney, Sydney, NSW, Australia
- School of Clinical Medicine, UNSW Medicine & Health, UNSW Sydney, Sydney, NSW, Australia
| | - Paul G Ekert
- Children's Cancer Institute, Lowy Cancer Research Centre, UNSW Sydney, Sydney, NSW, Australia.
- School of Clinical Medicine, UNSW Medicine & Health, UNSW Sydney, Sydney, NSW, Australia.
- University of New South Wales Centre for Childhood Cancer Research, UNSW Sydney, Sydney, NSW, Australia.
- Cancer Immunology Program, Peter MacCallum Cancer Centre, Parkville, VIC, Australia.
| | - Emmy D G Fleuren
- Children's Cancer Institute, Lowy Cancer Research Centre, UNSW Sydney, Sydney, NSW, Australia
- School of Clinical Medicine, UNSW Medicine & Health, UNSW Sydney, Sydney, NSW, Australia
- University of New South Wales Centre for Childhood Cancer Research, UNSW Sydney, Sydney, NSW, Australia
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3
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Darvishi E, Slemmons K, Wan Z, Mitra S, Hou X, Hugues Parmentier J, Eddie Loh YH, Helman LJ. Molecular mechanisms of Guadecitabine induced FGFR4 down regulation in alveolar rhabdomyosarcomas. Neoplasia 2020; 22:274-282. [PMID: 32464274 PMCID: PMC7251315 DOI: 10.1016/j.neo.2020.05.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 04/28/2020] [Accepted: 05/01/2020] [Indexed: 01/07/2023] Open
Abstract
Fibroblast growth factor receptor 4 (FGFR4) aberrant expression and activity have been linked to the pathogenesis of a variety of cancers including rhabdomyosarcomas (RMS). We found that treatment of alveolar rhabdomyosarcoma (aRMS) cells with Guadecitabine (SGI-110), a next-generation DNA methyltransferase inhibitor (DNMTi), resulted in a significant reduction of FGFR4 protein levels, 5 days post treatment. Chromatin immunoprecipitation-sequencing (ChIP-seq) in aRMS cells revealed attenuation of the H3K4 mono-methylation across the FGFR4 super enhancer without changes in tri-methylation of either H3K4 or H3K27. These changes were associated with a significant reduction in FGFR4 transcript levels in treated cells. These decreases in H3K4me1 in the FGFR4 super enhancer were also associated with a 240-fold increase in KDM5B (JARID1B) mRNA levels. Immunoblot and immunofluorescent studies also revealed a significant increase in the KDM5B protein levels after treatment in these cells. KDM5B is the only member of KDM5 (JARID1) family of histone lysine demethylases that catalyzes demethylation of H3K4me1. These data together suggest a pleiotropic effect of DNMTi therapy in aRMS cells, converging to significantly lower FGFR4 protein levels in these cells.
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MESH Headings
- Antineoplastic Agents/pharmacology
- Azacitidine/analogs & derivatives
- Azacitidine/pharmacology
- Cell Line, Tumor
- Cell Proliferation/drug effects
- Chromatin Immunoprecipitation Sequencing
- Down-Regulation/drug effects
- Enhancer Elements, Genetic
- Histones/metabolism
- Humans
- Jumonji Domain-Containing Histone Demethylases/metabolism
- Lysine/metabolism
- Nuclear Proteins/metabolism
- Receptor, Fibroblast Growth Factor, Type 4/genetics
- Receptor, Fibroblast Growth Factor, Type 4/metabolism
- Repressor Proteins/metabolism
- Rhabdomyosarcoma, Alveolar/drug therapy
- Rhabdomyosarcoma, Alveolar/genetics
- Rhabdomyosarcoma, Alveolar/metabolism
- Rhabdomyosarcoma, Alveolar/pathology
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Affiliation(s)
- Emad Darvishi
- Division of Hematology-Oncology, Cancer and Blood Disease Institute, Children's Hospital Los Angeles, Los Angeles, CA, USA
| | - Katherine Slemmons
- Division of Hematology-Oncology, Cancer and Blood Disease Institute, Children's Hospital Los Angeles, Los Angeles, CA, USA
| | - Zesheng Wan
- Division of Hematology-Oncology, Cancer and Blood Disease Institute, Children's Hospital Los Angeles, Los Angeles, CA, USA
| | - Sheetal Mitra
- Division of Hematology-Oncology, Cancer and Blood Disease Institute, Children's Hospital Los Angeles, Los Angeles, CA, USA
| | - Xiaogang Hou
- Division of Hematology-Oncology, Cancer and Blood Disease Institute, Children's Hospital Los Angeles, Los Angeles, CA, USA
| | - Jean Hugues Parmentier
- Division of Hematology-Oncology, Cancer and Blood Disease Institute, Children's Hospital Los Angeles, Los Angeles, CA, USA
| | | | - Lee J Helman
- Division of Hematology-Oncology, Cancer and Blood Disease Institute, Children's Hospital Los Angeles, Los Angeles, CA, USA; Keck School of Medicine, University of Southern California, Los Angeles, CA, USA.
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4
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Weiss A, Adler F, Buhles A, Stamm C, Fairhurst RA, Kiffe M, Sterker D, Centeleghe M, Wartmann M, Kinyamu-Akunda J, Schadt HS, Couttet P, Wolf A, Wang Y, Barzaghi-Rinaudo P, Murakami M, Kauffmann A, Knoepfel T, Buschmann N, Leblanc C, Mah R, Furet P, Blank J, Hofmann F, Sellers WR, Graus Porta D. FGF401, A First-In-Class Highly Selective and Potent FGFR4 Inhibitor for the Treatment of FGF19-Driven Hepatocellular Cancer. Mol Cancer Ther 2019; 18:2194-2206. [DOI: 10.1158/1535-7163.mct-18-1291] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2018] [Revised: 06/12/2019] [Accepted: 08/06/2019] [Indexed: 12/09/2022]
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5
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Lagutina IV, Valentine V, Picchione F, Harwood F, Valentine MB, Villarejo-Balcells B, Carvajal JJ, Grosveld GC. Modeling of the human alveolar rhabdomyosarcoma Pax3-Foxo1 chromosome translocation in mouse myoblasts using CRISPR-Cas9 nuclease. PLoS Genet 2015; 11:e1004951. [PMID: 25659124 PMCID: PMC4319822 DOI: 10.1371/journal.pgen.1004951] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Accepted: 12/10/2014] [Indexed: 01/01/2023] Open
Abstract
Many recurrent chromosome translocations in cancer result in the generation of fusion genes that are directly implicated in the tumorigenic process. Precise modeling of the effects of cancer fusion genes in mice has been inaccurate, as constructs of fusion genes often completely or partially lack the correct regulatory sequences. The reciprocal t(2;13)(q36.1;q14.1) in human alveolar rhabdomyosarcoma (A-RMS) creates a pathognomonic PAX3-FOXO1 fusion gene. In vivo mimicking of this translocation in mice is complicated by the fact that Pax3 and Foxo1 are in opposite orientation on their respective chromosomes, precluding formation of a functional Pax3-Foxo1 fusion via a simple translocation. To circumvent this problem, we irreversibly inverted the orientation of a 4.9 Mb syntenic fragment on chromosome 3, encompassing Foxo1, by using Cre-mediated recombination of two pairs of unrelated oppositely oriented LoxP sites situated at the borders of the syntenic region. We tested if spatial proximity of the Pax3 and Foxo1 loci in myoblasts of mice homozygous for the inversion facilitated Pax3-Foxo1 fusion gene formation upon induction of targeted CRISPR-Cas9 nuclease-induced DNA double strand breaks in Pax3 and Foxo1. Fluorescent in situ hybridization indicated that fore limb myoblasts show a higher frequency of Pax3/Foxo1 co-localization than hind limb myoblasts. Indeed, more fusion genes were generated in fore limb myoblasts via a reciprocal t(1;3), which expressed correctly spliced Pax3-Foxo1 mRNA encoding Pax3-Foxo1 fusion protein. We conclude that locus proximity facilitates chromosome translocation upon induction of DNA double strand breaks. Given that the Pax3-Foxo1 fusion gene will contain all the regulatory sequences necessary for precise regulation of its expression, we propose that CRISPR-Cas9 provides a novel means to faithfully model human diseases caused by chromosome translocation in mice.
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Affiliation(s)
- Irina V. Lagutina
- Departments of Genetics, St. Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
| | - Virginia Valentine
- Tumor Cell Biology, St. Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
| | - Fabrizio Picchione
- Departments of Genetics, St. Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
| | - Frank Harwood
- Departments of Genetics, St. Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
| | - Marcus B. Valentine
- Tumor Cell Biology, St. Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
| | | | - Jaime J. Carvajal
- Division of Cancer Biology, The Institute of Cancer Research, London, United Kingdom
- Centro Andaluz de Biología del Desarrollo (CSIC/UPO/JA), Sevilla, Spain
| | - Gerard C. Grosveld
- Departments of Genetics, St. Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
- * E-mail:
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6
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Thalhammer V, Lopez-Garcia LA, Herrero-Martin D, Hecker R, Laubscher D, Gierisch ME, Wachtel M, Bode P, Nanni P, Blank B, Koscielniak E, Schäfer BW. PLK1 phosphorylates PAX3-FOXO1, the inhibition of which triggers regression of alveolar Rhabdomyosarcoma. Cancer Res 2015; 75:98-110. [PMID: 25398439 DOI: 10.1158/0008-5472.can-14-1246] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Pediatric tumors harbor very low numbers of somatic mutations and therefore offer few targets to improve therapeutic management with targeted drugs. In particular, outcomes remain dismal for patients with metastatic alveolar rhabdomyosarcoma (aRMS), where the chimeric transcription factor PAX3/7-FOXO1 has been implicated but problematic to target. In this report, we addressed this challenge by developing a two-armed screen for druggable upstream regulatory kinases in the PAX3/7-FOXO1 pathway. Screening libraries of kinome siRNA and small molecules, we defined PLK1 as an upstream-acting regulator. Mechanistically, PLK1 interacted with and phosphorylated PAX3-FOXO1 at the novel site S503, leading to protein stabilization. Notably, PLK1 inhibition led to elevated ubiquitination and rapid proteasomal degradation of the PAX3-FOXO1 chimeric oncoprotein. On this basis, we embarked on a preclinical validation of PLK1 as a target in a xenograft mouse model of aRMS, where the PLK1 inhibitor BI 2536 reduced PAX3-FOXO1-mediated gene expression and elicited tumor regression. Clinically, analysis of human aRMS tumor biopsies documented high PLK1 expression to offer prognostic significance for both event-free survival and overall survival. Taken together, these preclinical studies validate the PLK1-PAX3-FOXO1 axis as a rational target to treat aRMS.
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Affiliation(s)
- Verena Thalhammer
- Department of Oncology and Children's Research Center, University Children's Hospital Zurich, Zurich, Switzerland
| | - Laura A Lopez-Garcia
- Department of Oncology and Children's Research Center, University Children's Hospital Zurich, Zurich, Switzerland
| | - David Herrero-Martin
- Department of Oncology and Children's Research Center, University Children's Hospital Zurich, Zurich, Switzerland
| | - Regina Hecker
- Department of Oncology and Children's Research Center, University Children's Hospital Zurich, Zurich, Switzerland
| | - Dominik Laubscher
- Department of Oncology and Children's Research Center, University Children's Hospital Zurich, Zurich, Switzerland
| | - Maria E Gierisch
- Department of Oncology and Children's Research Center, University Children's Hospital Zurich, Zurich, Switzerland
| | - Marco Wachtel
- Department of Oncology and Children's Research Center, University Children's Hospital Zurich, Zurich, Switzerland
| | - Peter Bode
- Department of Surgical Pathology, University Hospital Zurich, Zurich, Switzerland
| | - Paolo Nanni
- Functional Genomics Center Zurich, University of Zurich, Zurich, Switzerland
| | - Bernd Blank
- Department of Oncology/Hematology/Immunology, Olgahospital, Klinikum Stuttgart, Stuttgart, Germany
| | - Ewa Koscielniak
- Department of Oncology/Hematology/Immunology, Olgahospital, Klinikum Stuttgart, Stuttgart, Germany
| | - Beat W Schäfer
- Department of Oncology and Children's Research Center, University Children's Hospital Zurich, Zurich, Switzerland.
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7
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PAX3-FOXO1 induces up-regulation of Noxa sensitizing alveolar rhabdomyosarcoma cells to apoptosis. Neoplasia 2014; 15:738-48. [PMID: 23814486 DOI: 10.1593/neo.121888] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Revised: 04/05/2013] [Accepted: 04/11/2013] [Indexed: 02/08/2023] Open
Abstract
Alveolar rhabdomyosarcoma (ARMS) has a much poorer prognosis than the more common embryonal subtype. Most ARMS tumors characteristically possess a specific genomic translocation between the genes of PAX3/7 and FOXO1 (FKHR), which forms fusion proteins possessing the DNA binding domains of PAX3/7 and the more transcriptionally potent transactivation domain of FOXO1. We have shown that the proapoptotic BH3-only family member Noxa is upregulated by the PAX3-FOXO1 fusion transcription factor in a p53-independent manner. The increased expression of Noxa renders PAX3-FOXO1-expressing cells more susceptible to apoptosis induced by a γ-secretase inhibitor (GSI1, Z-LLNle-CHO), the proteasome inhibitor bortezomib, and BH3 mimetic ABT-737. Apoptosis in response to bortezomib can be overcome by shRNA knockdown of Noxa. In vivo treatment with bortezomib reduced the growth of tumors derived from a PAX3-FOXO1-expressing primary myoblast tumor model and RH41 xenografts. We therefore demonstrate that PAX3-FOXO1 up-regulation of Noxa represents an unanticipated aspect of ARMS tumor biology that creates a therapeutic window to allow induction of apoptosis in ARMS cells.
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8
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Sokolowski E, Turina CB, Kikuchi K, Langenau DM, Keller C. Proof-of-concept rare cancers in drug development: the case for rhabdomyosarcoma. Oncogene 2013; 33:1877-89. [PMID: 23665679 DOI: 10.1038/onc.2013.129] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2013] [Revised: 02/22/2013] [Accepted: 02/27/2013] [Indexed: 12/14/2022]
Abstract
Rare diseases typically affect fewer than 200,000 patients annually, yet because thousands of rare diseases exist, the cumulative impact is millions of patients worldwide. Every form of childhood cancer qualifies as a rare disease-including the childhood muscle cancer, rhabdomyosarcoma (RMS). The next few years promise to be an exceptionally good era of opportunity for public-private collaboration for rare and childhood cancers. Not only do certain governmental regulation advantages exist, but these advantages are being made permanent with special incentives for pediatric orphan drug-product development. Coupled with a growing understanding of sarcoma tumor biology, synergy with pharmaceutical muscle disease drug-development programs, and emerging publically available preclinical and clinical tools, the outlook for academic-community-industry partnerships in RMS drug development looks promising.
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Affiliation(s)
- E Sokolowski
- Department of Student Affairs, Oregon State University, Corvallis, OR, USA
| | - C B Turina
- 1] Department of Student Affairs, Oregon State University, Corvallis, OR, USA [2] Pediatric Cancer Biology Program, Department of Pediatrics, Papé Family Pediatric Research Institute, Oregon Health and Science University, Portland, OR, USA
| | - K Kikuchi
- Pediatric Cancer Biology Program, Department of Pediatrics, Papé Family Pediatric Research Institute, Oregon Health and Science University, Portland, OR, USA
| | - D M Langenau
- 1] Division of Molecular Pathology and Cancer Center, Massachusetts General Hospital, Boston, MA, USA [2] Harvard Medical School and Harvard Stem Cell Institute, Boston, MA, USA
| | - C Keller
- Pediatric Cancer Biology Program, Department of Pediatrics, Papé Family Pediatric Research Institute, Oregon Health and Science University, Portland, OR, USA
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9
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Caserto BG. A Comparative Review of Canine and Human Rhabdomyosarcoma With Emphasis on Classification and Pathogenesis. Vet Pathol 2013; 50:806-26. [DOI: 10.1177/0300985813476069] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Rhabdomyosarcomas are a diverse group of malignant mesenchymal neoplasms exhibiting variable levels of differentiation toward skeletal myocytes. Neoplastic cells may resemble relatively undifferentiated myoblasts, satellite cells, or more differentiated elongated spindle cells and multicellular myotubes. In veterinary medicine, classification into subtypes and variants is based on an outdated system derived from human pathology and is solely based on histologic characteristics. In contrast, classification of human rhabdomyosarcoma is based on histologic, immunohistochemical, and molecular diagnostic techniques, and subclassification has clinical and prognostic relevance. Relevance of tumor subtyping has not been established in veterinary medicine. Recent discoveries of components of the molecular pathogenesis and genomes of human rhabdomyosarcomas have led to new diagnostic techniques and revisions of the human classification system. The current classification system in veterinary medicine is reviewed in light of these changes. Diagnosis of rhabdomyosarcoma using histopathology, electron microscopy, and the clinical aspects of human and canine rhabdomyosarcomas is compared. The clinical features and biologic behavior of canine rhabdomyosarcomas are compared with canine soft tissue sarcomas.
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Affiliation(s)
- B. G. Caserto
- Cornell University College of Veterinary Medicine, Department of Biomedical Sciences, Ithaca, NY, USA
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Olanich ME, Barr FG. A call to ARMS: targeting the PAX3-FOXO1 gene in alveolar rhabdomyosarcoma. Expert Opin Ther Targets 2013; 17:607-23. [PMID: 23432728 DOI: 10.1517/14728222.2013.772136] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
INTRODUCTION Expression of fusion oncoproteins generated by recurrent chromosomal translocations represents a major tumorigenic mechanism characteristic of multiple cancers, including one-third of all sarcomas. Oncogenic fusion genes provide novel targets for therapeutic intervention. The PAX3-FOXO1 oncoprotein in alveolar rhabdomyosarcoma (ARMS) is presented as a paradigm to examine therapeutic strategies for targeting sarcoma-associated fusion genes. AREAS COVERED This review discusses the role of PAX3-FOXO1 in ARMS tumors. Besides evaluating various approaches to molecularly target PAX3-FOXO1 itself, this review highlights therapeutically attractive downstream genes activated by PAX3-FOXO1. EXPERT OPINION Oncogenic fusion proteins represent desirable therapeutic targets because their expression is specific to tumor cells, but these fusions generally characterize rare malignancies. Full development and testing of potential drugs targeted to these fusions are complicated by the small numbers of patients in these disease categories. Although efforts to develop targeted therapies against fusion proteins should continue, molecular targets that are applicable to a broader tumor landscape should be pursued. A shift of the traditional paradigm to view therapeutic intervention as target-specific rather than tumor-specific will help to circumvent the challenges posed by rare tumors and maximize the possibility of developing successful new treatments for patients with these rare translocation-associated sarcomas.
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Affiliation(s)
- Mary E Olanich
- National Institutes of Health, National Cancer Institute, Center for Cancer Research, Laboratory of Pathology , Bethesda, MD 20892, USA
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11
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Marshall AD, Grosveld GC. Alveolar rhabdomyosarcoma - The molecular drivers of PAX3/7-FOXO1-induced tumorigenesis. Skelet Muscle 2012. [PMID: 23206814 PMCID: PMC3564712 DOI: 10.1186/2044-5040-2-25] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Rhabdomyosarcoma is a soft tissue sarcoma arising from cells of a mesenchymal or skeletal muscle lineage. Alveolar rhabdomyosarcoma (ARMS) is more aggressive than the more common embryonal (ERMS) subtype. ARMS is more prone to metastasis and carries a poorer prognosis. In contrast to ERMS, the majority of ARMS tumors carry one of several characteristic chromosomal translocations, such as t(2;13)(q35;q14), which results in the expression of a PAX3-FOXO1 fusion transcription factor. In this review we discuss the genes that cooperate with PAX3-FOXO1, as well as the target genes of the fusion transcription factor that contribute to various aspects of ARMS tumorigenesis. The characterization of these pathways will lead to a better understanding of ARMS tumorigenesis and will allow the design of novel targeted therapies that will lead to better treatment for this aggressive pediatric tumor.
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Affiliation(s)
- Amy D Marshall
- Department of Genetics, St Jude Children's Research Hospital, Memphis, TN, 38105, USA.
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12
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Crose LES, Etheridge KT, Chen C, Belyea B, Talbot LJ, Bentley RC, Linardic CM. FGFR4 blockade exerts distinct antitumorigenic effects in human embryonal versus alveolar rhabdomyosarcoma. Clin Cancer Res 2012; 18:3780-90. [PMID: 22648271 DOI: 10.1158/1078-0432.ccr-10-3063] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Rhabdomyosarcoma (RMS) is a malignancy with features of skeletal muscle, and the most common soft tissue sarcoma of childhood. Survival for high-risk groups is approximately 30% at 5 years and there are no durable therapies tailored to its genetic aberrations. During genetic modeling of the common RMS variants, embryonal RMS (eRMS) and alveolar RMS (aRMS), we noted that the receptor tyrosine kinase (RTK) fibroblast growth factor receptor 4 (FGFR4) was upregulated as an early event in aRMS. Herein, we evaluated the expression of FGFR4 in eRMS compared with aRMS, and whether FGFR4 had similar or distinct roles in their tumorigenesis. EXPERIMENTAL DESIGN Human RMS cell lines and tumor tissue were analyzed for FGFR4 expression by immunoblot and immunohistochemistry. Genetic and pharmacologic loss-of-function of FGFR4 using virally transduced short hairpin RNA (shRNA) and the FGFR small-molecule inhibitor PD173074, respectively, were used to study the role of FGFR4 in RMS cell lines in vitro and xenografts in vivo. Expression of the antiapoptotic protein BCL2L1 was also examined. RESULTS FGFR4 is expressed in both RMS subtypes, but protein expression is higher in aRMS. The signature aRMS gene fusion product, PAX3-FOXO1, induced FGFR4 expression in primary human myoblasts. In eRMS, FGFR4 loss-of-function reduced cell proliferation in vitro and xenograft formation in vivo. In aRMS, it diminished cell survival in vitro. In myoblasts and aRMS, FGFR4 was necessary and sufficient for expression of BCL2L1 whereas in eRMS, this induction was not observed, suggesting differential FGFR4 signaling. CONCLUSION These studies define dichotomous roles for FGFR4 in RMS subtypes, and support further study of FGFR4 as a therapeutic target.
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Affiliation(s)
- Lisa E S Crose
- Department of Pediatrics, Duke University Medical Center, Durham, NC, USA
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