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Yang J, Dong X, Wen H, Li Y, Wang X, Yan S, Zuo C, Lyu L, Zhang K, Qi X. FGFs function in regulating myoblasts differentiation in spotted sea bass (Lateolabrax maculatus). Gen Comp Endocrinol 2024; 347:114426. [PMID: 38103843 DOI: 10.1016/j.ygcen.2023.114426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 12/11/2023] [Accepted: 12/11/2023] [Indexed: 12/19/2023]
Abstract
Fibroblast growth factors (FGFs) are a family of structurally related peptides that regulate processes such as cell proliferation, differentiation, and damage repair. In our previous study, fibroblast growth factor receptor 4 (fgfr4) was detected in the most significant quantitative trait loci (QTL), when identified of QTLs and genetic markers for growth-related traits in spotted sea bass. However, knowledge of the function of fgfr4 is lacking, even the legends to activate the receptor is unknown in fish. To remedy this problem, in the present study, a total of 33 fgfs were identified from the genomic and transcriptomic databases of spotted sea bass, of which 10 were expressed in the myoblasts. According to the expression pattern during myoblasts proliferation and differentiation, fgf6a, fgf6b and fgf18 were selected for further prokaryotic expression and purification. The recombinant proteins FGF6a, FGF6b and FGF18 were found to inhibit myoblast differentiation. Overall, our results provide a theoretical basis for the molecular mechanisms of growth regulation in economic fish such as spotted sea bass.
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Affiliation(s)
- Jing Yang
- Key Laboratory of Mariculture, Ministry of Education (KLMME), Ocean University of China, Qingdao 266003
| | - Ximeng Dong
- Key Laboratory of Mariculture, Ministry of Education (KLMME), Ocean University of China, Qingdao 266003
| | - Haishen Wen
- Key Laboratory of Mariculture, Ministry of Education (KLMME), Ocean University of China, Qingdao 266003
| | - Yun Li
- Key Laboratory of Mariculture, Ministry of Education (KLMME), Ocean University of China, Qingdao 266003
| | - Xiaojie Wang
- Key Laboratory of Mariculture, Ministry of Education (KLMME), Ocean University of China, Qingdao 266003
| | - Shaojing Yan
- Key Laboratory of Mariculture, Ministry of Education (KLMME), Ocean University of China, Qingdao 266003
| | - Chenpeng Zuo
- Key Laboratory of Mariculture, Ministry of Education (KLMME), Ocean University of China, Qingdao 266003
| | - Likang Lyu
- Key Laboratory of Mariculture, Ministry of Education (KLMME), Ocean University of China, Qingdao 266003
| | - Kaiqiang Zhang
- Key Laboratory of Mariculture, Ministry of Education (KLMME), Ocean University of China, Qingdao 266003
| | - Xin Qi
- Key Laboratory of Mariculture, Ministry of Education (KLMME), Ocean University of China, Qingdao 266003.
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Ferreira A, Timmerman E, Staes A, Vuylsteke M, De Muynck L, Gevaert K. Protein interactors of 3-O sulfated heparan sulfates in human MCI and age-matched control cerebrospinal fluid. Sci Data 2023; 10:121. [PMID: 36879013 PMCID: PMC9986659 DOI: 10.1038/s41597-023-02009-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 02/07/2023] [Indexed: 03/08/2023] Open
Abstract
Heparan sulfates (HS) proteoglycans are commonly found on the cell surface and mediate many processes. Binding of HS ligands is determined by the sulfation code on the HS chain that can be N-/2-O/6-O- or 3-O-sulfated, generating heterogenous sulfation patterns. 3-O sulfated HS (3S-HS) play a role in several (patho)physiological processes such as blood coagulation, viral pathogenesis and binding and internalization of tau in Alzheimer's disease. However, few 3S-HS-specific interactors are known. Thus, our insight into the role of 3S-HS in health and disease is limited, especially in the central nervous system. Using human CSF, we determined the interactome of synthetic HS with defined sulfation patterns. Our affinity-enrichment mass spectrometry studies expand the repertoire of proteins that may interact with (3S-)HS. Validating our approach, ATIII, a known 3S-HS interactor, was found to require GlcA-GlcNS6S3S for binding, similar to what has been reported. Our dataset holds novel, potential HS and 3S-HS protein ligands, that can be explored in future studies focusing on molecular mechanisms that depend on 3S-HS in (patho)physiological conditions.
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Affiliation(s)
- Andreia Ferreira
- Janssen Research & Development, a Division of Janssen Pharmaceutica N.V., 2340, Beerse, Belgium
- VIB-UGent Center for Medical Biotechnology, B-9052 Ghent, Belgium; Department of Biomolecular Medicine, Ghent University, B-9052, Ghent, Belgium
| | - Evy Timmerman
- VIB-UGent Center for Medical Biotechnology, B-9052 Ghent, Belgium; Department of Biomolecular Medicine, Ghent University, B-9052, Ghent, Belgium
- VIB Proteomics Core, B-9000 Ghent, Belgium; Department of Biomolecular Medicine, Ghent University, B-9000, Ghent, Belgium
| | - An Staes
- VIB-UGent Center for Medical Biotechnology, B-9052 Ghent, Belgium; Department of Biomolecular Medicine, Ghent University, B-9052, Ghent, Belgium
| | | | - Louis De Muynck
- Janssen Research & Development, a Division of Janssen Pharmaceutica N.V., 2340, Beerse, Belgium.
| | - Kris Gevaert
- VIB-UGent Center for Medical Biotechnology, B-9052 Ghent, Belgium; Department of Biomolecular Medicine, Ghent University, B-9052, Ghent, Belgium.
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3
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Danielsson A, Kogut MM, Maszota-Zieleniak M, Chopra P, Boons GJ, Samsonov SA. Molecular Dynamics-based descriptors of 3-O-Sulfated Heparan Sulfate as Contributors of Protein Binding Specificity. Comput Biol Chem 2022; 99:107716. [DOI: 10.1016/j.compbiolchem.2022.107716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 06/03/2022] [Accepted: 06/20/2022] [Indexed: 11/03/2022]
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4
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Sadeghi S, Kalhor H, Panahi M, Abolhasani H, Rahimi B, Kalhor R, Mehrabi A, Vahdatinia M, Rahimi H. Keratinocyte growth factor in focus: A comprehensive review from structural and functional aspects to therapeutic applications of palifermin. Int J Biol Macromol 2021; 191:1175-1190. [PMID: 34606789 DOI: 10.1016/j.ijbiomac.2021.09.151] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 09/21/2021] [Accepted: 09/22/2021] [Indexed: 11/29/2022]
Abstract
Palifermin (Kepivance™) is the first therapeutic approved by the Food and Drug Administration for preventing and managing the oral mucositis provoked by myelotoxic and mucotoxic therapies. Palifermin is a recombinant protein generated from human keratinocyte growth factor (KGF) and imitates the function of endogenous KGF. KGF is an epithelial mitogen involved in various biological processes which belongs to the FGF family. KGF possesses a high level of receptor specificity and plays an important role in tissue repair and maintaining of the mucosal barrier integrity. Based on these unique features, palifermin was developed to enhance the growth of damaged epithelial tissues. Administration of palifermin has shown success in the reduction of toxicities of chemotherapy and radiotherapy, and improvement of the patient's quality of life. Notwithstanding all merits, the clinical application of palifermin is limited owing to its instability and production challenges. Hence, a growing number of ongoing researches are designed to deal with these problems and enhance the physicochemical and pharmaceutical properties of palifermin. In the current review, we discuss KGF structure and function, potential therapeutic applications of palifermin, as well as the latest progress in the production of recombinant human KGF and its challenges ahead.
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Affiliation(s)
- Solmaz Sadeghi
- Molecular Medicine Department, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran
| | - Hourieh Kalhor
- Molecular Medicine Department, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran; Cellular and Molecular Research Center, Qom University of Medical Sciences, Qom, Iran
| | - Mohammad Panahi
- Department of Medical Biotechnology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Hoda Abolhasani
- Cellular and Molecular Research Center, Qom University of Medical Sciences, Qom, Iran; Department of Pharmacology, School of Medicine, Qom University of Medical Sciences, Qom, Iran
| | - Bahareh Rahimi
- Department of Medical Biotechnology, Faculty of Applied Medical Sciences, Iran University of Medical Sciences, Tehran, Iran
| | - Reyhaneh Kalhor
- Cellular and Molecular Research Center, Qom University of Medical Sciences, Qom, Iran; Department of Genetics, Colleague of Sciences, Kazerun Branch, Islamic Azad University, Kazerun, Iran
| | - Amirmehdi Mehrabi
- Department of Pharmacoeconomy & Administrative Pharmacy, School Of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| | - Mahsa Vahdatinia
- Molecular Medicine Department, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran
| | - Hamzeh Rahimi
- Molecular Medicine Department, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran.
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The 3- O-sulfation of heparan sulfate modulates protein binding and lyase degradation. Proc Natl Acad Sci U S A 2021; 118:2012935118. [PMID: 33441484 DOI: 10.1073/pnas.2012935118] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Humans express seven heparan sulfate (HS) 3-O-sulfotransferases that differ in substrate specificity and tissue expression. Although genetic studies have indicated that 3-O-sulfated HS modulates many biological processes, ligand requirements for proteins engaging with HS modified by 3-O-sulfate (3-OS) have been difficult to determine. In particular, the context in which the 3-OS group needs to be presented for binding is largely unknown. We describe herein a modular synthetic approach that can provide structurally diverse HS oligosaccharides with and without 3-OS. The methodology was employed to prepare 27 hexasaccharides that were printed as a glycan microarray to examine ligand requirements of a wide range of HS-binding proteins. The binding selectivity of antithrombin-III (AT-III) compared well with anti-Factor Xa activity supporting robustness of the array technology. Many of the other examined HS-binding proteins required an IdoA2S-GlcNS3S6S sequon for binding but exhibited variable dependence for the 2-OS and 6-OS moieties, and a GlcA or IdoA2S residue neighboring the central GlcNS3S. The HS oligosaccharides were also examined as inhibitors of cell entry by herpes simplex virus type 1, which, surprisingly, showed a lack of dependence of 3-OS, indicating that, instead of glycoprotein D (gD), they competitively bind to gB and gC. The compounds were also used to examine substrate specificities of heparin lyases, which are enzymes used for depolymerization of HS/heparin for sequence determination and production of therapeutic heparins. It was found that cleavage by lyase II is influenced by 3-OS, while digestion by lyase I is only affected by 2-OS. Lyase III exhibited sensitivity to both 3-OS and 2-OS.
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6
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Gulberti S, Mao X, Bui C, Fournel-Gigleux S. The role of heparan sulfate maturation in cancer: A focus on the 3O-sulfation and the enigmatic 3O-sulfotransferases (HS3STs). Semin Cancer Biol 2020; 62:68-85. [DOI: 10.1016/j.semcancer.2019.10.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 10/10/2019] [Accepted: 10/11/2019] [Indexed: 01/05/2023]
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7
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Lan Y, Li X, Liu Y, He Y, Hao C, Wang H, Jin L, Zhang G, Zhang S, Zhou A, Zhang L. Pingyangmycin inhibits glycosaminoglycan sulphation in both cancer cells and tumour tissues. J Cell Mol Med 2020; 24:3419-3430. [PMID: 32068946 PMCID: PMC7131950 DOI: 10.1111/jcmm.15017] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 01/05/2020] [Accepted: 01/10/2020] [Indexed: 12/18/2022] Open
Abstract
Pingyangmycin is a clinically used anticancer drug and induces lung fibrosis in certain cancer patients. We previously reported that the negatively charged cell surface glycosaminoglycans are involved in the cellular uptake of the positively charged pingyangmycin. However, it is unknown if pingyangmycin affects glycosaminoglycan structures. Seven cell lines and a Lewis lung carcinoma‐injected C57BL/6 mouse model were used to understand the cytotoxicity of pingyangmycin and its effect on glycosaminoglycan biosynthesis. Stable isotope labelling coupled with LC/MS method was used to quantify glycosaminoglycan disaccharide compositions from pingyangmycin‐treated and untreated cell and tumour samples. Pingyangmycin reduced both chondroitin sulphate and heparan sulphate sulphation in cancer cells and in tumours. The effect was persistent at different pingyangmycin concentrations and at different exposure times. Moreover, the cytotoxicity of pingyangmycin was decreased in the presence of soluble glycosaminoglycans, in the glycosaminoglycan‐deficient cell line CHO745, and in the presence of chlorate. A flow cytometry‐based cell surface FGF/FGFR/glycosaminoglycan binding assay also showed that pingyangmycin changed cell surface glycosaminoglycan structures. Changes in the structures of glycosaminoglycans may be related to fibrosis induced by pingyangmycin in certain cancer patients.
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Affiliation(s)
- Ying Lan
- Systems Biology & Medicine Center for Complex Diseases, Affiliated Hospital of Qingdao University, Qingdao, China.,College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Xiulian Li
- Systems Biology & Medicine Center for Complex Diseases, Affiliated Hospital of Qingdao University, Qingdao, China
| | - Yong Liu
- Systems Biology & Medicine Center for Complex Diseases, Affiliated Hospital of Qingdao University, Qingdao, China
| | - Yanli He
- Systems Biology & Medicine Center for Complex Diseases, Affiliated Hospital of Qingdao University, Qingdao, China
| | - Cui Hao
- Systems Biology & Medicine Center for Complex Diseases, Affiliated Hospital of Qingdao University, Qingdao, China
| | - Hua Wang
- Systems Biology & Medicine Center for Complex Diseases, Affiliated Hospital of Qingdao University, Qingdao, China
| | - Liying Jin
- Systems Biology & Medicine Center for Complex Diseases, Affiliated Hospital of Qingdao University, Qingdao, China
| | - Guoqing Zhang
- Systems Biology & Medicine Center for Complex Diseases, Affiliated Hospital of Qingdao University, Qingdao, China
| | - Shufeng Zhang
- College of Chemistry, Tianjin Normal University, Tianjin, China
| | - Aimin Zhou
- Clinical Chemistry Program, Department of Chemistry, Cleveland State University, Cleveland, OH, USA
| | - Lijuan Zhang
- Systems Biology & Medicine Center for Complex Diseases, Affiliated Hospital of Qingdao University, Qingdao, China
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8
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Sun C, Liu M, Sun P, Yang M, Yates EA, Guo Z, Fernig DG. Sulfated polysaccharides interact with fibroblast growth factors and protect from denaturation. FEBS Open Bio 2019; 9:1477-1487. [PMID: 31271519 PMCID: PMC6668377 DOI: 10.1002/2211-5463.12696] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 06/26/2019] [Accepted: 07/03/2019] [Indexed: 01/08/2023] Open
Abstract
Fibroblast growth factors (FGFs) regulate embryonic development and homeostasis, including tissue and organ repair and specific aspects of metabolism. The basic FGF and acidic FGF, now known as FGF2 and FGF1, are widely used protein drugs for tissue repair. However, they are susceptible to denaturation at ambient temperatures and during long-time storage, which will reduce their biological activity. The interaction of FGFs with the sulfated domains of heparan sulfate and heparin is essential for their cellular signaling and stability. Therefore, we analyzed the interactions of FGF1 and FGF2 with four sulfated polysaccharides: heparin, dextran sulfate (DXS), λ-carrageenan, and chondroitin sulfate. The results of thermal stability and cell proliferation assays demonstrate that heparin, DXS, and λ-carrageenan bound to both FGFs and protected them from denaturation. Our results suggest heparin, DXS, and λ-carrageenan are potential formulation materials that bind and stabilize FGFs, and which may also potentiate their activity and control their delivery.
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Affiliation(s)
- Changye Sun
- Henan Key Laboratory of Medical Tissue RegenerationXinxiang Medical UniversityChina
| | - Mengxin Liu
- Henan Key Laboratory of Medical Tissue RegenerationXinxiang Medical UniversityChina
| | - Panwen Sun
- Henan Key Laboratory of Medical Tissue RegenerationXinxiang Medical UniversityChina
| | - Mingming Yang
- Department of CardiologySchool of MedicineAffiliated Zhongda HospitalSoutheast UniversityNanjingChina
| | - Edwin A. Yates
- Department of BiochemistryInstitute of Integrative BiologyUniversity of LiverpoolUK
| | - Zhikun Guo
- Henan Key Laboratory of Medical Tissue RegenerationXinxiang Medical UniversityChina
| | - David G. Fernig
- Department of BiochemistryInstitute of Integrative BiologyUniversity of LiverpoolUK
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9
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Zinkle A, Mohammadi M. Structural Biology of the FGF7 Subfamily. Front Genet 2019; 10:102. [PMID: 30809251 PMCID: PMC6379346 DOI: 10.3389/fgene.2019.00102] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Accepted: 01/29/2019] [Indexed: 11/13/2022] Open
Abstract
Mammalian fibroblast growth factor (FGF) signaling is intricately regulated via selective binding interactions between 18 FGF ligands and four FGF receptors (FGFR1–4), three of which (FGFR1–3) are expressed as either epithelial (“b”) or mesenchymal (“c”) splice isoforms. The FGF7 subfamily, consisting of FGF3, FGF7, FGF10, and FGF22, is unique among FGFs in that its members are secreted exclusively by the mesenchyme, and specifically activate the “b” isoforms of FGFR1 (FGFR1b) and FGFR2 (FGFR2b) present in the overlying epithelium. This unidirectional mesenchyme-to-epithelium signaling contributes to the development of essentially all organs, glands, and limbs. Structural analysis has shown that members of the FGF7 subfamily achieve their restricted specificity for FGFR1b/FGFR2b by engaging in specific contacts with two alternatively spliced loop regions in the immunoglobulin-like domain 3 (D3) of these receptors. Weak basal receptor-binding affinity further constrains the FGF7 subfamily’s specificity for FGFR1b/2b. In this review, we elaborate on the structural determinants of FGF7 subfamily receptor-binding specificity, and discuss how affinity differences among the four members for the heparin sulfate (HS) co-receptor contribute to their disparate biological activities.
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Affiliation(s)
- Allen Zinkle
- Department of Biochemistry and Molecular Pharmacology, New York University Langone Medical Center, New York, NY, United States
| | - Moosa Mohammadi
- Department of Biochemistry and Molecular Pharmacology, New York University Langone Medical Center, New York, NY, United States
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10
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Alavi Naini SM, Soussi-Yanicostas N. Heparan Sulfate as a Therapeutic Target in Tauopathies: Insights From Zebrafish. Front Cell Dev Biol 2018; 6:163. [PMID: 30619849 PMCID: PMC6306439 DOI: 10.3389/fcell.2018.00163] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 11/15/2018] [Indexed: 12/13/2022] Open
Abstract
Microtubule-associated protein tau (MAPT) hyperphosphorylation and aggregation, are two hallmarks of a family of neurodegenerative disorders collectively referred to as tauopathies. In many tauopathies, including Alzheimer's disease (AD), progressive supranuclear palsy (PSP) and Pick's disease, tau aggregates are found associated with highly sulfated polysaccharides known as heparan sulfates (HSs). In AD, amyloid beta (Aβ) peptide aggregates associated with HS are also characteristic of disease. Heparin, an HS analog, promotes misfolding, hyperphosphorylation and aggregation of tau protein in vitro. HS also provides cell surface receptors for attachment and uptake of tau seeds, enabling their propagation. These findings point to HS-tau interactions as potential therapeutic targets in tauopathies. The zebrafish genome contains genes paralogous to MAPT, genes orthologous to HS biosynthetic and chain modifier enzymes, and other genes implicated in AD. The nervous system in the zebrafish bears anatomical and chemical similarities to that in humans. These homologies, together with numerous technical advantages, make zebrafish a valuable model for investigating basic mechanisms in tauopathies and identifying therapeutic targets. Here, we comprehensively review current knowledge on the role of HSs in tau pathology and HS-targeting therapeutic approaches. We also discuss novel insights from zebrafish suggesting a role for HS 3-O-sulfated motifs in tau pathology and establishing HS antagonists as potential preventive agents or therapies for tauopathies.
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Affiliation(s)
- Seyedeh Maryam Alavi Naini
- Department of Neuroscience, Institut de Biologie Paris Seine (IBPS), INSERM, CNRS, Sorbonne Université, Paris, France
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Li JP, Kusche-Gullberg M. Heparan Sulfate: Biosynthesis, Structure, and Function. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2016; 325:215-73. [PMID: 27241222 DOI: 10.1016/bs.ircmb.2016.02.009] [Citation(s) in RCA: 182] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Heparan sulfate (HS) proteoglycans (PGs) are ubiquitously expressed on cell surfaces and in the extracellular matrix of most animal tissues, having essential functions in development and homeostasis, as well as playing various roles in disease processes. The functions of HSPGs are mainly dependent on interactions between the HS-side chains with a variety of proteins including cytokines, growth factors, and their receptors. In a given HS polysaccharide, negatively charged sulfate and carboxylate groups are arranged in various types of domains, generated through strictly regulated biosynthetic reactions and with enormous potential for structural variability. The mode of HS-protein interactions is assessed through binding experiments using saccharides of defined composition in vitro, signaling assays in cell models where HS structures are manipulated, and targeted disruption of genes for biosynthetic enzymes in animals (mouse, zebrafish, Drosophila, and Caenorhabditis elegans) followed by phenotype analysis. Whereas some protein ligands appear to require strictly defined HS structure, others bind to variable saccharide domains without apparent dependence on distinct saccharide sequence. These findings raise intriguing questions concerning the functional significance of regulation in HS biosynthesis and the potential for development of therapeutics targeting HS-protein interactions.
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Affiliation(s)
- J-P Li
- Department of Medical Biochemistry and Microbiology, University of Uppsala, Uppsala, Sweden; SciLifeLab, University of Uppsala, Uppsala, Sweden.
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12
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Li X, Wang C, Xiao J, McKeehan WL, Wang F. Fibroblast growth factors, old kids on the new block. Semin Cell Dev Biol 2016; 53:155-67. [PMID: 26768548 DOI: 10.1016/j.semcdb.2015.12.014] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Accepted: 12/18/2015] [Indexed: 01/08/2023]
Abstract
The fibroblast growth factors (FGFs) are a family of cell intrinsic regulatory peptides that control a broad spectrum of cellular activities. The family includes canonic FGFs that elicit their activities by activating the FGF receptor (FGFR) tyrosine kinase and non-canonic members that elicit their activities intracellularly and via FGFR-independent mechanisms. The FGF signaling axis is highly complex due to the existence of multiple isoforms of both ligands and receptors, as well as cofactors that include the chemically heterogeneous heparan sulfate (HS) cofactors, and in the case of endocrine FGFs, the Klotho coreceptors. Resident FGF signaling controls embryonic development, maintains tissue homeostasis, promotes wound healing and tissue regeneration, and regulates functions of multiple organs. However, ectopic or aberrant FGF signaling is a culprit for various diseases, including congenital birth defects, metabolic disorder, and cancer. The molecular mechanisms by which the specificity of FGF signaling is achieved remain incompletely understood. Since its application as a druggable target has been gradually recognized by pharmaceutical companies and translational researchers, understanding the determinants of FGF signaling specificity has become even more important in order to get into the position to selectively suppress a particular pathway without affecting others to minimize side effects.
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Affiliation(s)
- Xiaokun Li
- College of Pharmacy, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Cong Wang
- College of Pharmacy, Wenzhou Medical University, Wenzhou, Zhejiang, China.
| | - Jian Xiao
- College of Pharmacy, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Wallace L McKeehan
- Institute of Biosciences and Technology, Texas A&M University Health Science Center, Houston, TX 77030-3303, United States
| | - Fen Wang
- Institute of Biosciences and Technology, Texas A&M University Health Science Center, Houston, TX 77030-3303, United States.
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13
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Abstract
Numerous proteins, including cytokines and chemokines, enzymes and enzyme inhibitors, extracellular matrix proteins, and membrane receptors, bind heparin. Although they are traditionally classified as heparin-binding proteins, under normal physiological conditions these proteins actually interact with the heparan sulfate chains of one or more membrane or extracellular proteoglycans. Thus, they are more appropriately classified as heparan sulfate-binding proteins (HSBPs). This review provides an overview of the various modes of interaction between heparan sulfate and HSBPs, emphasizing biochemical and structural insights that improve our understanding of the many biological functions of heparan sulfate.
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Affiliation(s)
- Ding Xu
- Department of Cellular and Molecular Medicine, Glycobiology Research and Training Center, University of California, San Diego, La Jolla, California 92093; ,
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14
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Thacker BE, Xu D, Lawrence R, Esko JD. Heparan sulfate 3-O-sulfation: a rare modification in search of a function. Matrix Biol 2013; 35:60-72. [PMID: 24361527 DOI: 10.1016/j.matbio.2013.12.001] [Citation(s) in RCA: 157] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Revised: 12/03/2013] [Accepted: 12/03/2013] [Indexed: 02/02/2023]
Abstract
Many protein ligands bind to heparan sulfate, which results in their presentation, protection, oligomerization or conformational activation. Binding depends on the pattern of sulfation and arrangement of uronic acid epimers along the chains. Sulfation at the C3 position of glucosamine is a relatively rare, yet biologically significant modification, initially described as a key determinant for binding and activation of antithrombin and later for infection by type I herpes simplex virus. In mammals, a family of seven heparan sulfate 3-O-sulfotransferases installs sulfate groups at this position and constitutes the largest group of sulfotransferases involved in heparan sulfate formation. However, to date very few proteins or biological systems have been described that are influenced by 3-O-sulfation. This review describes our current understanding of the prevalence and structure of 3-O-sulfation sites, expression and substrate specificity of the 3-O-sulfotransferase family and the emerging roles of 3-O-sulfation in biology.
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Affiliation(s)
- Bryan E Thacker
- Department of Cellular and Molecular Medicine, Glycobiology Research and Training Center, University of California, San Diego, La Jolla, CA 92093-0687, United States; Biomedical Sciences Graduate Program, University of California, San Diego, La Jolla, CA 92093-0687, United States
| | - Ding Xu
- Department of Cellular and Molecular Medicine, Glycobiology Research and Training Center, University of California, San Diego, La Jolla, CA 92093-0687, United States
| | - Roger Lawrence
- Department of Cellular and Molecular Medicine, Glycobiology Research and Training Center, University of California, San Diego, La Jolla, CA 92093-0687, United States
| | - Jeffrey D Esko
- Department of Cellular and Molecular Medicine, Glycobiology Research and Training Center, University of California, San Diego, La Jolla, CA 92093-0687, United States; Biomedical Sciences Graduate Program, University of California, San Diego, La Jolla, CA 92093-0687, United States.
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15
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Mechanisms of pituitary tumorigenesis. Mol Oncol 2013. [DOI: 10.1017/cbo9781139046947.059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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16
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17
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Cattaruzza S, Ozerdem U, Denzel M, Ranscht B, Bulian P, Cavallaro U, Zanocco D, Colombatti A, Stallcup WB, Perris R. Multivalent proteoglycan modulation of FGF mitogenic responses in perivascular cells. Angiogenesis 2012; 16:309-27. [PMID: 23124902 DOI: 10.1007/s10456-012-9316-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2012] [Accepted: 10/12/2012] [Indexed: 01/10/2023]
Abstract
Sprouting of angiogenic perivascular cells is thought to be highly dependent upon autocrine and paracrine growth factor stimulation. Accordingly, we report that corneal angiogenesis induced by ectopic FGF implantation is strongly impaired in NG2/CSPG4 proteoglycan (PG) null mice known to harbour a putative deficit in pericyte proliferation/mobilization. Conversely, no significant differences were seen between wild type and knockout corneas when VEGF was used as an angiocrine factor. Perturbed responsiveness of NG2-deficient pericytes to paracrine and autocrine stimulation by several FGFs could be confirmed in cells isolated from NG2 null mice, while proliferation induced by other growth factors was equivalent in wild type and knockout cells. Identical results were obtained after siRNA-mediated knock-down of NG2 in human smooth muscle-like cell lines, as also demonstrated by the decreased levels of FGF receptor phosphorylation detected in these NG2 deprived cells. Binding assays with recombinant proteins and molecular interactions examined on live cells asserted that FGF-2 bound to NG2 in a glycosaminoglycan-independent, core protein-mediated manner and that the PG was alone capable of retaining FGF-2 on the cell membrane for subsequent receptor presentation. The use of dominant-negative mutant cells, engineered by combined transduction of NG2 deletion constructs and siRNA knock-down of the endogenous PG, allowed us to establish that the FGF co-receptor activity of NG2 is entirely mediated by its extracellular portion. In fact, forced overexpression of the NG2 ectodomain in human smooth muscle-like cells increased their FGF-2-induced mitosis and compensated for low levels of FGF receptor surface expression, in a manner equivalent to that produced by overexpression of the full-length NG2. Upon FGF binding, the cytoplasmic domain of NG2 is phosphorylated, but there is no evidence that this event elicits signal transductions that could bypass the FGFR-mediated ones. Pull-down experiments, protein-protein binding assays and flow cytometry FRET coherently revealed an elective ligand-independent association of NG2 with FGFR1 and FGFR3. The NG2 cooperation with these receptors was also corroborated functionally by the outcome of FGF-2 treatments of cells engineered to express diverse NG2/FGFR combinations. Comprehensively, the findings suggest that perivascular NG2 may serve as a dual modulator of the availability/accessibility of FGF at the cell membrane, as well as the resulting FGFR transducing activity.
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Affiliation(s)
- Sabrina Cattaruzza
- S.O.C. for Experimental Oncology 2, The National Cancer Institute Aviano, CRO-IRCCS, Via Pedemontana Occidentale 12, 33081, Aviano, PN, Italy.
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18
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The breast cancer susceptibility gene product fibroblast growth factor receptor 2 serves as a scaffold for regulation of NF-κB signaling. Mol Cell Biol 2012; 32:4662-73. [PMID: 22988296 DOI: 10.1128/mcb.00935-12] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Fibroblast growth factor (FGF) receptor 2 (FGFR2) has been identified in genome-wide association studies to be associated with increased breast cancer risk; however, its mechanism of action remains unclear. Here we show that the two major FGFR2 alternatively spliced isoforms, FGFR2-IIIb and FGFR2-IIIc, interact with IκB kinase β and its downstream target, NF-κB. FGFR2 inhibits nuclear RelA/p65 NF-κB translocation and activity and reduces expression of dependent transcripts, including interleukin-6. These interactions result in diminished STAT3 phosphorylation and reduced breast cancer cell growth, motility, and invasiveness. FGFR2 also arrests the epithelial cell-to-mesenchymal cell transition (EMT), resulting in attenuated neoplastic growth in orthotopic xenografts of breast cancer cells. Our studies provide strong evidence for the protective effects of FGFR2 on tumor progression. We propose that FGFR2 serves as a scaffold for multiple components of the NF-κB signaling complex. Through these interactions, FGFR2 isoforms can respond to tissue-specific FGF signals to modulate epithelial cell-stromal cell communications in cancer progression.
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19
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Yang C, Jin C, Li X, Wang F, McKeehan WL, Luo Y. Differential specificity of endocrine FGF19 and FGF21 to FGFR1 and FGFR4 in complex with KLB. PLoS One 2012; 7:e33870. [PMID: 22442730 PMCID: PMC3307775 DOI: 10.1371/journal.pone.0033870] [Citation(s) in RCA: 125] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2011] [Accepted: 02/19/2012] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Recent studies suggest that betaKlotho (KLB) and endocrine FGF19 and FGF21 redirect FGFR signaling to regulation of metabolic homeostasis and suppression of obesity and diabetes. However, the identity of the predominant metabolic tissue in which a major FGFR-KLB resides that critically mediates the differential actions and metabolism effects of FGF19 and FGF21 remain unclear. METHODOLOGY/PRINCIPAL FINDINGS We determined the receptor and tissue specificity of FGF21 in comparison to FGF19 by using direct, sensitive and quantitative binding kinetics, and downstream signal transduction and expression of early response gene upon administration of FGF19 and FGF21 in mice. We found that FGF21 binds FGFR1 with much higher affinity than FGFR4 in presence of KLB; while FGF19 binds both FGFR1 and FGFR4 in presence of KLB with comparable affinity. The interaction of FGF21 with FGFR4-KLB is very weak even at high concentration and could be negligible at physiological concentration. Both FGF19 and FGF21 but not FGF1 exhibit binding affinity to KLB. The binding of FGF1 is dependent on where FGFRs are present. Both FGF19 and FGF21 are unable to displace the FGF1 binding, and conversely FGF1 cannot displace FGF19 and FGF21 binding. These results indicate that KLB is an indispensable mediator for the binding of FGF19 and FGF21 to FGFRs that is not required for FGF1. Although FGF19 can predominantly activate the responses of the liver and to a less extent the adipose tissue, FGF21 can do so significantly only in the adipose tissue and adipocytes. Among several metabolic and endocrine tissues, the response of adipose tissue to FGF21 is predominant, and can be blunted by the ablation of KLB or FGFR1. CONCLUSIONS Our results indicate that unlike FGF19, FGF21 is unable to bind FGFR4-KLB complex with affinity comparable to FGFR1-KLB, and therefore, at physiological concentration less likely to directly and significantly target the liver where FGFR4-KLB predominantly resides. However, both FGF21 and FGF19 have the potential to activate responses of primarily the adipose tissue where FGFR1-KLB resides.
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MESH Headings
- Adipose Tissue
- Animals
- Cell Line, Tumor
- Diabetes Mellitus/genetics
- Diabetes Mellitus/metabolism
- Fibroblast Growth Factors/genetics
- Fibroblast Growth Factors/metabolism
- Humans
- Klotho Proteins
- Membrane Proteins/genetics
- Membrane Proteins/metabolism
- Mice
- Mice, Knockout
- Multiprotein Complexes/genetics
- Multiprotein Complexes/metabolism
- Obesity/genetics
- Obesity/metabolism
- Protein Binding
- Receptor, Fibroblast Growth Factor, Type 1/genetics
- Receptor, Fibroblast Growth Factor, Type 1/metabolism
- Receptor, Fibroblast Growth Factor, Type 4/genetics
- Receptor, Fibroblast Growth Factor, Type 4/metabolism
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Affiliation(s)
- Chaofeng Yang
- Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, Texas, United States of America
| | - Chengliu Jin
- Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, Texas, United States of America
| | - Xiaokun Li
- School of Pharmacy, Wenzhou Medical College, Wenzhou, China
| | - Fen Wang
- Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, Texas, United States of America
| | - Wallace L. McKeehan
- Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, Texas, United States of America
- IBT Proteomics and Nanotechnology Laboratory, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, Texas, United States of America
| | - Yongde Luo
- Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, Texas, United States of America
- IBT Proteomics and Nanotechnology Laboratory, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, Texas, United States of America
- * E-mail:
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20
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Guo M, Liu W, Serra S, Asa SL, Ezzat S. FGFR2 isoforms support epithelial-stromal interactions in thyroid cancer progression. Cancer Res 2012; 72:2017-27. [PMID: 22345151 DOI: 10.1158/0008-5472.can-11-3985] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Alternate splicing yields two distinct isoforms of the fibroblast growth factor (FGF) receptor FGFR2-IIIb and FGFR2-IIIc varying their extracellular structure in human thyroid cancer, in which FGFR expression is commonly dysregulated. In this study, we characterized the function of these variants in modulating thyroid cancer behavior. Enforced expression of either FGFR2-IIIb or FGFR2-IIIc in thyroid epithelial cancer cells reduced expression of fibronectin, MAGE-A3 and MMP9, while increasing p21 and enhancing Rb dephosphorylation. Consistent with these tumor-suppressive properties, FGFR2-IIIb and FGFR2-IIIc each diminished invasive behavior in vitro and reduced tumor growth and metastasis in vivo. Notably, these effects contrasted with those produced by expression of these FGFR isoforms in fibroblasts, in which they both stimulated cell growth. Moreover, in xenograft tumors generated by coimplantation of epithelial and fibroblast cells expressing that same isoform, there was no significant effect on tumor progression. Conversely, FGFR2-IIIb expression in epithelial cells yielded higher FGF4/FGF7 expression that, in the presence of FGFR2-IIIc-expressing fibroblasts, enhanced tumor progression. Together, our findings highlight the importance of cellular context in assigning growth properties to growth factor receptor isoforms. More specifically, they show how alternative splicing of FGFR2 yields heteroisoforms critical to the growth-promoting actions of FGFs that exert distinct epithelial-stromal effects in thyroid cancer.
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Affiliation(s)
- Miao Guo
- The Ontario Cancer Institute, Department of Medicine, University Health Network, Toronto, Ontario, Canada
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21
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Harvey DJ. Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: an update for the period 2005-2006. MASS SPECTROMETRY REVIEWS 2011; 30:1-100. [PMID: 20222147 DOI: 10.1002/mas.20265] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
This review is the fourth update of the original review, published in 1999, on the application of MALDI mass spectrometry to the analysis of carbohydrates and glycoconjugates and brings coverage of the literature to the end of 2006. The review covers fundamental studies, fragmentation of carbohydrate ions, method developments, and applications of the technique to the analysis of different types of carbohydrate. Specific compound classes that are covered include carbohydrate polymers from plants, N- and O-linked glycans from glycoproteins, glycated proteins, glycolipids from bacteria, glycosides, and various other natural products. There is a short section on the use of MALDI-TOF mass spectrometry for the study of enzymes involved in glycan processing, a section on industrial processes, particularly the development of biopharmaceuticals and a section on the use of MALDI-MS to monitor products of chemical synthesis of carbohydrates. Large carbohydrate-protein complexes and glycodendrimers are highlighted in this final section.
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Affiliation(s)
- David J Harvey
- Department of Biochemistry, Oxford Glycobiology Institute, University of Oxford, Oxford OX1 3QU, UK.
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22
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Luo Y, Yang C, Lu W, Xie R, Jin C, Huang P, Wang F, McKeehan WL. Metabolic regulator betaKlotho interacts with fibroblast growth factor receptor 4 (FGFR4) to induce apoptosis and inhibit tumor cell proliferation. J Biol Chem 2010; 285:30069-78. [PMID: 20657013 PMCID: PMC2943257 DOI: 10.1074/jbc.m110.148288] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2010] [Revised: 07/16/2010] [Indexed: 11/06/2022] Open
Abstract
In organs involved in metabolic homeostasis, transmembrane α and βklothos direct FGFR signaling to control of metabolic pathways. Coordinate expression of βklotho and FGFR4 is a property of mature hepatocytes. Genetic deletion of FGFR4 or βklotho in mice disrupts hepatic cholesterol/bile acid and lipid metabolism. The deletion of FGFR4 has no effect on the proliferative response of hepatocytes after liver injury. However, its absence results in accelerated progression of dimethynitrosamine-initiated hepatocellular carcinomas, indicating that FGFR4 suppresses hepatoma proliferation. The mechanism underlying the FGFR4-mediated hepatoma suppression has not been addressed. Here we show that βklotho expression is more consistently down-regulated in human and mouse hepatomas than FGFR4. Co-expression and activation by either endocrine FGF19 or cellular FGF1 of the FGFR4 kinase in a complex with βklotho restricts cell population growth through induction of apoptotic cell death in both hepatic and nonhepatic cells. The βklotho-FGFR4 partnership caused a depression of activated AKT and mammalian target of rapamycin while activating ERK1/2 that may underlie the pro-apoptotic effect. Our results show that βklotho not only interacts with heparan sulfate-FGFR4 to form a complex with high affinity for endocrine FGF19 but also impacts the quality of downstream signaling and biological end points activated by either FGF19 or canonical FGF1. Thus the same βklotho-heparan sulfate-FGFR4 partnership that mediates endocrine control of hepatic metabolism plays a role in cellular homeostasis and hepatoma suppression through negative control of cell population growth mediated by pro-apoptotic signaling.
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Affiliation(s)
- Yongde Luo
- From the IBT Proteomics and Nanotechnology Laboratory and
- the Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A & M Health Science Center and
| | - Chaofeng Yang
- the Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A & M Health Science Center and
| | - Weiqin Lu
- the Department of Molecular Pathology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030
| | - Rui Xie
- From the IBT Proteomics and Nanotechnology Laboratory and
| | - Chengliu Jin
- the Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A & M Health Science Center and
| | - Peng Huang
- the Department of Molecular Pathology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030
| | - Fen Wang
- the Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A & M Health Science Center and
| | - Wallace L. McKeehan
- From the IBT Proteomics and Nanotechnology Laboratory and
- the Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A & M Health Science Center and
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23
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24
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Zhu X, Asa SL, Ezzat S. Genetic and epigenetic mechanisms down-regulate FGF receptor 2 to induce melanoma-associated antigen A in breast cancer. THE AMERICAN JOURNAL OF PATHOLOGY 2010; 176:2333-43. [PMID: 20348248 DOI: 10.2353/ajpath.2010.091049] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Recent genome-wide association studies have identified single nucleotide polymorphisms (SNPs) in the gene encoding fibroblast growth factor receptor 2 (FGFR2) as a risk factor for breast cancer. We examined the relationship between these intron 2 SNPs and gene expression in breast carcinomas. Primary breast tissue showed a common occurrence of these SNPs accompanied by FGFR2 expression in normal ductal epithelium. Unexpectedly, we found that FGFR2 mRNA and protein levels were reduced in microdissected cancer cells when compared with paired normal breast epithelium. FGFR2 down-regulation was associated with DNA methylation and loss-of-heterozygosity. Where FGFR2-IIIb was expressed in tumor cells, it was accompanied by up-regulation of the RNA-binding proteins ESRP1/2, consistent with splicing of this isoform. Reduction in FGFR2 was associated with re-expression of its putative target melanoma-associated antigen (MAGE-A) in primary carcinoma cells. Conversely, forced expression or activation of FGFR2-IIIb resulted in MAGE-A silencing. These data provide the first evidence for FGFR2 down-regulation in breast carcinomas harboring intron 2 SNPs. Our findings underscore the significance of epigenetic and somatic changes that can potentially modify the effects of germline polymorphisms in determining FGFR2 gene expression.
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Affiliation(s)
- Xuegong Zhu
- Department of Medicine, University Health Network, University of Toronto, Toronto, Ontario, Canada
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25
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Kirn-Safran C, Farach-Carson MC, Carson DD. Multifunctionality of extracellular and cell surface heparan sulfate proteoglycans. Cell Mol Life Sci 2009; 66:3421-34. [PMID: 19629389 PMCID: PMC11115568 DOI: 10.1007/s00018-009-0096-1] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2009] [Revised: 07/01/2009] [Accepted: 07/06/2009] [Indexed: 02/06/2023]
Abstract
Heparan sulfate proteoglycans are a remarkably diverse family of glycosaminoglycan-bearing protein cores that include the syndecans, the glypicans, perlecan, agrin, and collagen XVIII. Members of this protein class play key roles during normal processes that occur during development, tissue morphogenesis, and wound healing. As key components of basement membranes in organs and tissues, they also participate in selective filtration of biological fluids, in establishing cellular barriers, and in modulation of angiogenesis. The ability to perform these functions is provided both by the features of the protein cores as well as by the unique properties of heparan sulfate, which is assembled as a polymer of N-acetylglucosamine and glucuronic acid and modified by specific enzymes to generate specialized biologically active structures. This article discusses the structures and functions of this amazing family of proteoglycans and provides a platform for further study of the individual members.
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Affiliation(s)
| | - Mary C. Farach-Carson
- Department of Biological Sciences, University of Delaware, Newark, DE 19707 USA
- Present Address: Department of Biochemistry and Cell Biology, Weiss School of Natural Sciences, Rice University, MS-102, P.O. Box 1892, Houston, TX 77251-1892 USA
| | - Daniel D. Carson
- Present Address: Department of Biochemistry and Cell Biology, Weiss School of Natural Sciences, Rice University, MS-102, P.O. Box 1892, Houston, TX 77251-1892 USA
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26
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Makarenkova HP, Hoffman MP, Beenken A, Eliseenkova AV, Meech R, Tsau C, Patel VN, Lang RA, Mohammadi M. Differential interactions of FGFs with heparan sulfate control gradient formation and branching morphogenesis. Sci Signal 2009; 2:ra55. [PMID: 19755711 DOI: 10.1126/scisignal.2000304] [Citation(s) in RCA: 137] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The developmental activities of morphogens depend on the gradients that they form in the extracellular matrix. Here, we show that differences in the binding of fibroblast growth factor 7 (FGF7) and FGF10 to heparan sulfate (HS) underlie the formation of different gradients that dictate distinct activities during branching morphogenesis. Reducing the binding affinity of FGF10 for HS by mutating a single residue in its HS-binding pocket converted FGF10 into a functional mimic of FGF7 with respect to gradient formation and regulation of branching morphogenesis. In particular, the mutant form of FGF10 caused lacrimal and salivary gland epithelium buds to branch rather than to elongate. In contrast, mutations that reduced the affinity of the FGF10 for its receptor affected the extent, but not the nature, of the response. Our data may provide a general model for understanding how binding to HS regulates other morphogenetic gradients.
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Affiliation(s)
- Helen P Makarenkova
- The Neurobiology Department, The Scripps Research Institute, La Jolla, CA 92037, USA.
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27
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Luo Y, Yang C, Jin C, Xie R, Wang F, McKeehan WL. Novel phosphotyrosine targets of FGFR2IIIb signaling. Cell Signal 2009; 21:1370-8. [PMID: 19410646 PMCID: PMC2782441 DOI: 10.1016/j.cellsig.2009.04.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2009] [Accepted: 04/27/2009] [Indexed: 02/07/2023]
Abstract
In partnership exclusively with the epithelial FGFR2IIIb isotype and a structurally-specific heparan sulfate motif, stromal-derived FGF7 delivers both growth-promoting and growth-limiting differentiation signals to epithelial cells that promote cellular homeostasis between stromal and epithelial compartments. Intercompartmental homeostasis supported by FGF7/FGFR2IIIb is subverted in many solid epithelial tumors. The normally mesenchymal-derived homologue FGFR1 drives proliferation and a progressive tumor-associated phenotype when it appears ectopically in epithelial cells. In order to understand the mechanism underlying the unique biological effects of FGFR2IIIb, we developed an inducible FGFR2IIIb expression system that is specifically dependent on FGF7 for activation in an initially unresponsive cell line to avoid selection for only the growth-promoting aspects of FGFR2IIIb signaling. We then determined FGF7/FGFR2IIIb signaling-specific tyrosine phosphorylated proteins within 5 min after FGF7 stimulation by phosphopeptide immunoaffinity purification and nano-LC-MS/MS. The FGF7/FGFR2 pair caused tyrosine phosphorylation of multiple proteins that have been implicated in the growth stimulating activities of FGFR1 that included multi-substrate organizers FRS2alpha and IRS4, ERK2 and phosphatases SHP2 and SHIP2. It uniquely phosphorylated CDK2 and phosphatase PTPN18 on sites involved in the attenuation of cell proliferation, and several factors that maintain nuclear-cytosolic relationships (emerin and LAP2), protein structure and other cellular fine structures as well as some proteins of unknown functions. Several of the FGF7/FGFR2IIIb-specific targets have been associated with maintenance of function and tumor suppression and disruption in tumors. In contrast, a number of pTyr substrates associated with FGF2/FGFR1 that are generally associated with intracellular Ca(2+)-phospholipid signaling, membrane and cytoskeletal plasticity, cell adhesion, migration and the tumorigenic phenotype were not observed with FGF7/FGFR2IIIb. Our findings provide specific downstream targets for dissection of causal relationships underlying the distinct role of FGF7/FGFR2IIIb signaling in epithelial cell homeostasis.
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Affiliation(s)
- Yongde Luo
- IBT Proteomics and Nanotechnology Laboratory, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, Texas 77030-3303, USA
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28
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Kirn-Safran C, Farach-Carson MC, Carson DD. Multifunctionality of extracellular and cell surface heparan sulfate proteoglycans. Cell Mol Life Sci 2009. [DOI: 10.1007/s00018-009-0096-1 doi:dx.doi.org] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/29/2022]
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29
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Zhu X, Asa SL, Ezzat S. Histone-acetylated control of fibroblast growth factor receptor 2 intron 2 polymorphisms and isoform splicing in breast cancer. Mol Endocrinol 2009; 23:1397-405. [PMID: 19497954 DOI: 10.1210/me.2009-0071] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Recent genome-wide association studies have identified fibroblast growth factor receptor (FGFR)2 as one of a few candidate genes linked with breast cancer susceptibility. In particular, the disease-predisposing allele of FGFR2 is inherited as a 7.5-kb region within intron 2 that harbors eight single nucleotide polymorphisms. The relationship between these single nucleotide polymorphisms and FGFR2 gene expression remains unclear. Here we show the common occurrence of polymorphisms within the intron 2 region in a panel of 10 breast cancer cell lines. High FGFR2-expressing cell lines such as MCF-7 cells displayed polymorphic sequences with constitutive histone acetylation at multiple intron 2 sequences harboring putative transcription binding sites. Knockdown of Runx2 or CCAAT enhancer binding protein beta in these cells resulted in diminished endogenous FGFR2 gene expression. In contrast FGFR2-negative MDA-231 cells were wild type and showed evidence of histone 3/4 deacetylation at the rs2981578, rs10736303, and rs7895676 disease-associated alleles that harbor binding sites for Runx2, estrogen receptor, and CCAAT enhancer binding protein beta, respectively. Histone deacetylation inhibition with trichostatin A resulted in enhanced acetylation at these intron 2 sites, an effect associated with robust FGFR2 reexpression. Isoform analysis proved reexpression of the FGFR2-IIIc variant the splicing of which was positively influenced by trichostatin A-mediated recruitment of the Fas-activated serine/threonine phosphoprotein survival protein. Our findings highlight the potential role of histone acetylation in modulating access to selected polymorphic sites within intron 2 as well as downstream splicing sites in generating variable FGFR2 levels and isoforms in breast cancer.
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Affiliation(s)
- Xuegong Zhu
- Department of Medicine, and the Endocrine Oncology Site Group, Princess Margaret Hospital, Ontario Cancer Institute, University Health Network, Toronto, Ontario, Canada M5G 2M9
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Abstract
Epigenetically-mediated gene dysregulation is a common feature associated with human pituitary tumorigenesis. The mechanisms leading to these changes, however, remain largely unknown. In this review, we examine changes responsible for DNA and histone modifications as independent, butpotentially interrlated modes of communication effecting chromatin remodeling. The dynamic properties of the enzymes involved in these reactions is highlighted. We use the fibroblast growth factor receptor 2 (FGFR2) as a model through which the p53-regulating melanoma-associated antigen (MAGE) system is governing in pituitary cells. The pathogenetic and potential therapeutic implications are discussed.
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Affiliation(s)
- Shereen Ezzat
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada
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31
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Zhu X, Asa SL, Ezzat S. Fibroblast growth factor 2 and estrogen control the balance of histone 3 modifications targeting MAGE-A3 in pituitary neoplasia. Clin Cancer Res 2008; 14:1984-96. [PMID: 18381936 DOI: 10.1158/1078-0432.ccr-07-2003] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Four members of the fibroblast growth factor receptor (FGFR) family transduce signals of a diverse group of FGF ligands. The FGFR2-IIIb isoform is abundantly present in the normal pituitary gland with contrasting down-regulation in neoplastic pituitary cells. cDNA profiling identified the cancer-testis antigen melanoma-associated antigen A3 (MAGE-A3) as a putative target negatively regulated by FGFR2. EXPERIMENTAL DESIGN Comparisons were made between normal and neoplastic human and mouse pituitary cells. Gene expression was examined by reverse transcription-PCR, DNA methylation was determined by methylation-specific PCR and combined bisulfite restriction analysis, and histone modification marks were identified by chromatin immunoprecipitation. RESULTS Normal human pituitary tissue that expresses FGFR2-IIIb does not express MAGE-A3; in contrast, pituitary tumors that are FGFR2 negative show abundant MAGE-A3 mRNA expression. MAGE-A3 expression correlates with the presence and extent of DNA promoter methylation; more frequent and higher-degree methylation is present in the normal gland compared with pituitary tumors. Conversely, pituitary tumors are hypomethylated, particularly in females where MAGE-A3 expression is nearly thrice higher than in males. Estradiol treatment induces MAGE-A3 through enhanced histone 3 acetylation and diminished methylation. The effects of estradiol are directly opposed by FGF7/FGFR2-IIIb. Down-regulation of MAGE-A3 results in p53 transcriptional induction, also through reciprocal histone acetylation and methylation modifications. CONCLUSIONS These findings highlight MAGE-A3 as a target of FGFR2-IIIb and estrogen action and provide evidence for a common histone-modifying network in the control of the balance between opposing signals.
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Affiliation(s)
- Xuegong Zhu
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada
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32
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Zhu X, Lee K, Asa SL, Ezzat S. Epigenetic silencing through DNA and histone methylation of fibroblast growth factor receptor 2 in neoplastic pituitary cells. THE AMERICAN JOURNAL OF PATHOLOGY 2007; 170:1618-28. [PMID: 17456767 PMCID: PMC1854956 DOI: 10.2353/ajpath.2007.061111] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 02/06/2007] [Indexed: 01/07/2023]
Abstract
Four members of the fibroblast growth factor receptor (FGFR) family of tyrosine kinases transduce signals of a diverse group of more than 23 fibroblast growth factor (FGF) ligands. Each prototypic receptor is composed of three immunoglobulin-like extracellular domains, two of which are involved in ligand binding. Alternative RNA splicing of one of two exons results in two different forms of the second half of the third immunoglobulin-like domain, the IIIb or IIIc isoforms. The contribution of each receptor and their isoforms in tumorigenesis remains unknown. In the pituitary, FGFR2 is expressed primarily as the IIIb isoform in normal adenohypophysial cells. In contrast, FGFR2 is significantly down-regulated in mouse corticotroph AtT20 tumor cells where the 5' promoter is methylated. Treatment of AtT20 cells with 5'-azacytidine resulted in FGFR2 re-expression, mainly as the FGFR2-IIIb isoform. Chromatin immunoprecipitation revealed evidence of histone methylation, but not of deacetylation, in the silencing of FGFR2 in AtT20 cells. Exposure of these cells to the cognate FGFR2-IIIb ligand FGF-7 resulted in diminished Rb phosphorylation and accumulation of p21 and p27, indicating diminished cell cycle progression. Examination of primary human pituitary adenomas revealed FGFR2 down-regulation in 52% (11 of 21) of samples and FGFR2 promoter DNA methylation in 45% (10 of 22) of samples. These data highlight the contribution from DNA and histone methylation as epigenetic mechanisms responsible for FGFR2 silencing in pituitary neoplasia.
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Affiliation(s)
- Xuegong Zhu
- Department of Medicine, Mount Sinai Hospital and University of Toronto, Canada
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Luo Y, Huang X, McKeehan WL. High yield, purity and activity of soluble recombinant Bacteroides thetaiotaomicron GST-heparinase I from Escherichia coli. Arch Biochem Biophys 2007; 460:17-24. [PMID: 17346663 PMCID: PMC1993911 DOI: 10.1016/j.abb.2007.01.029] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2007] [Revised: 01/24/2007] [Accepted: 01/25/2007] [Indexed: 11/18/2022]
Abstract
Heparinase I from Flavobacterium heparinum, a source of diverse polysaccharidases, suffers from low yields, insufficient purity for structural studies and insolubility when expressed as a recombinant product in Escherichia coli that is devoid of glycosaminoglycan polysaccharidases. In this study, cDNA coding for the orthologue of F. heparinum heparinase I was constructed from genomic information from the mammalian gut symbiont Bacteroides thetaiotaomicron and expressed in E. coli as a fusion protein with GST at the N-terminus. This resulted in high yield (30 mg/g dry bacteria) of soluble product and facilitated one-step affinity purification to homogeneity. Purified heparinase I bearing the GST fusion exhibited a K(m) of 2.3 microM and V(max) of 42.7 micromol/min with a specific activity of 164 U/mg with heparin (average 12,000 Da) as substrate. The results indicate a 2-fold improvement in yield, specific activity and affinity for heparin as substrate over previous reports. The data suggest that the heparinase I from the gut symbiont exhibits a higher intrinsic affinity for heparin than that from F. heparinum. The purified GST fusion enzyme exhibited a requirement for Ca(2+) and a pH optimum between 6.7 and 7.3 that was similar to the enzyme freed of the N-terminal GST portion. Our study revealed that catalytic activity of heparinase I requires a reducing environment. The GST facilitated immobilization of heparinase I in solid phase either for clinical purposes or for structural studies in absence of interference by contaminating polysaccharidases.
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Affiliation(s)
- Yongde Luo
- Center for Cancer and Stem Cell Biology (formerly Cancer Biology and Nutrition), Texas A&M University, Institute of Biosciences and Technology (IBT), The Texas A&M Health Science Center, 2121 W. Holcombe Blvd., Houston, Texas 77030-3303, USA
| | - Xinqiang Huang
- Center for Cancer and Stem Cell Biology (formerly Cancer Biology and Nutrition), Texas A&M University, Institute of Biosciences and Technology (IBT), The Texas A&M Health Science Center, 2121 W. Holcombe Blvd., Houston, Texas 77030-3303, USA
| | - Wallace L. McKeehan
- Center for Cancer and Stem Cell Biology (formerly Cancer Biology and Nutrition), Texas A&M University, Institute of Biosciences and Technology (IBT), The Texas A&M Health Science Center, 2121 W. Holcombe Blvd., Houston, Texas 77030-3303, USA
- Department of Biochemistry and Biophysics, Texas A&M University, Institute of Biosciences and Technology (IBT), The Texas A&M Health Science Center, 2121 W. Holcombe Blvd., Houston, Texas 77030-3303, USA
- *Corresponding author: Phone: 713-677-7522; Fax: 713-677-7512;
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Huang X, Yu C, Jin C, Yang C, Xie R, Cao D, Wang F, McKeehan WL. Forced expression of hepatocyte-specific fibroblast growth factor 21 delays initiation of chemically induced hepatocarcinogenesis. Mol Carcinog 2007; 45:934-42. [PMID: 16929488 DOI: 10.1002/mc.20241] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Inappropriate fibroblast growth factor (FGF) signaling is involved in most tissue-specific pathologies including cancer. Previously we showed that inappropriate expression and chronic activity of FGF receptor (FGFR) 1 in hepatocytes accelerated diethylnitrosamine (DEN)-initiated hepatocarcinogenesis. Here we showed that although widely expressed FGF1 and FGF2 are frequently upregulated in hepatocellular carcinoma (HCC), germline deletion of both FGF1 and FGF2 had no effect on DEN-initiated hepatocarcinogenesis. Thus overexpression of FGF1 or FGF2 may be a consequence rather than contributor to hepatoma progression. FGF21 is the first of 22 homologues whose expression has been reported to be preferentially in the liver. We showed that similar to FGF1 and FGF2, FGF21 mRNA was upregulated in neoplastic and regenerating liver after partial hepatectomy (PH) and CCl4 administration. In situ hybridization analysis confirmed that in contrast to FGF1 and FGF2, expression of FGF21 mRNA was limited to hepatocytes. Forced overexpression of FGF21 in hepatocytes by gene targeting had no apparent impact on normal liver development and compensatory response to injury. Surprisingly, overexpression of FGF21 delayed the appearance of DEN-induced liver tumors. At 8 and 10 mo, only 10% and 30% of transgenic mice, respectively, developed adenomas compared to 50% (all adenomas) and 80% (60% adenoma/20% HCC) in the wild-type (WT) mice. However, the incidence and burden of HCC at 10 mo and later was equal in the FGF21 transgenic and WT mice. We propose that FGF21 may delay development of adenomas through activation of resident hepatocyte FGFR4 at early times, but counteracts the delay by acceleration of progression to HCC through interaction with ectopic FGFR1 once it appears in hepatoma cells. This indicates a dual function of FGF21 that may reflect changes in FGFR isotype during progression of differentiated hepatoma cells.
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MESH Headings
- Animals
- Carbon Tetrachloride/toxicity
- Carcinoma, Hepatocellular/chemically induced
- Carcinoma, Hepatocellular/genetics
- Carcinoma, Hepatocellular/pathology
- Cell Transformation, Neoplastic/chemically induced
- Cell Transformation, Neoplastic/genetics
- Cell Transformation, Neoplastic/pathology
- Fibroblast Growth Factor 1/antagonists & inhibitors
- Fibroblast Growth Factor 1/genetics
- Fibroblast Growth Factor 1/physiology
- Fibroblast Growth Factor 2/antagonists & inhibitors
- Fibroblast Growth Factor 2/genetics
- Fibroblast Growth Factor 2/physiology
- Fibroblast Growth Factors/antagonists & inhibitors
- Fibroblast Growth Factors/genetics
- Fibroblast Growth Factors/physiology
- Gene Targeting
- Hepatocytes/metabolism
- Hepatocytes/pathology
- Liver Neoplasms/chemically induced
- Liver Neoplasms/genetics
- Liver Neoplasms/pathology
- Mice
- Mice, Transgenic
- RNA, Messenger/analysis
- RNA, Messenger/metabolism
- Receptor, Fibroblast Growth Factor, Type 4/agonists
- Receptor, Fibroblast Growth Factor, Type 4/metabolism
- Transcriptional Activation
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Affiliation(s)
- Xinqiang Huang
- Center for Cancer Biology and Nutrition, Institute of Biosciences and Technology, Texas A&M University System Health Science Center, Houston, Texas 77030, USA
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Luo Y, Ye S, Kan M, McKeehan WL. Control of fibroblast growth factor (FGF) 7- and FGF1-induced mitogenesis and downstream signaling by distinct heparin octasaccharide motifs. J Biol Chem 2006; 281:21052-21061. [PMID: 16728399 DOI: 10.1074/jbc.m601559200] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Variation in length, disaccharide composition, and sulfation of heparan sulfate (HS) affects fibroblast growth factor (FGF) signaling. However, it is unclear whether the specific distribution of groups within oligosaccharides or random variations in charge density underlies the effects. Recently we showed that a mixture of undersulfated octasaccharides exhibiting 7 and 8 sulfates (7,8-S-OctaF7) generated from heparin had the highest affinity for FGF7 monitored by salt resistance (>0.60 M salt) of octasaccharide-FGF7 complexes. 7,8-S-OctaF7 also had the highest specific activity for formation of a complex with dimeric FGFR2IIIb competent to bind FGF7. Here we show that when endogenous HS was inhibited by chlorate treatment, 7,8-S-OctaF7 specifically supported FGF7-stimulated DNA synthesis and downstream signaling in FGFR2IIIb-expressing mouse keratinocytes. It failed to support FGF1 signaling in both HS-deficient mouse keratinocytes and 3T3 fibroblasts. In contrast, abundant, more highly sulfated and heterogenous mixtures of octasaccharides with lower affinity (0.30-0.60 M salt) for FGF7 supported FGF1-induced signaling in both cell types. In contrast to the two-component 7,8-S-OctaF7 mixture from FGF7, the high affinity octasaccharide fraction from FGF1 was a heterogeneous mixture with components ranging from 8 to 12 sulfates with 11-S-octasaccharides the most abundant. The high affinity fraction exhibited similar properties to the lower affinity fractions from both FGF1 and FGF7. Octasaccharide mixtures eluting from FGF1 between 0.30 and 0.60 M and above 0.60 M salt were nearly equal in support of FGF1 signaling in fibroblasts and keratinocytes. Both were deficient in support of FGF7-induced signaling in keratinocytes. The results show that both variations in overall charge density and specific distribution of charged groups within HS motifs exhibit FGF-specific control over formation of FGF-HS-FGFR complexes and downstream signaling.
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Affiliation(s)
- Yongde Luo
- Center for Cancer Biology and Nutrition, Institute of Biosciences and Technology, The Texas A&M University System Health Science Center, Houston, Texas 77030-3303
| | - Sheng Ye
- Department of Physiology, The University of Texas Southwestern Medical Center, Dallas, Texas 75390-9040
| | - Mikio Kan
- Zeria Pharmaceutical Co., Ltd., GS PlatZ., 2512-1, Oshikiri, Kohnan-Machi, Ohsato-Gun, Saitama 360-0111, Japan
| | - Wallace L McKeehan
- Center for Cancer Biology and Nutrition, Institute of Biosciences and Technology, The Texas A&M University System Health Science Center, Houston, Texas 77030-3303; Department of Biochemistry and Biophysics, Texas A&M University, Houston, Texas 77030-3303.
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