1
|
Alalwany RH, Hawtrey T, Morgan K, Morris JC, Donaldson LF, Bates DO. Vascular endothelial growth factor isoforms differentially protect neurons against neurotoxic events associated with Alzheimer's disease. Front Mol Neurosci 2023; 16:1181626. [PMID: 37456522 PMCID: PMC10349181 DOI: 10.3389/fnmol.2023.1181626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 05/16/2023] [Indexed: 07/18/2023] Open
Abstract
Alzheimer's disease (AD) is the most common cause of dementia, the chronic and progressive deterioration of memory and cognitive abilities. AD can be pathologically characterised by neuritic plaques and neurofibrillary tangles, formed by the aberrant aggregation of β-amyloid and tau proteins, respectively. We tested the hypothesis that VEGF isoforms VEGF-A165a and VEGF-A165b, produced by differential splice site selection in exon 8, could differentially protect neurons from neurotoxicities induced by β-amyloid and tau proteins, and that controlling expression of splicing factor kinase activity could have protective effects on AD-related neurotoxicity in vitro. Using oxidative stress, β-amyloid, and tau hyperphosphorylation models, we investigated the effect of VEGF-A splicing isoforms, previously established to be neurotrophic agents, as well as small molecule kinase inhibitors, which selectively inhibit SRPK1, the major regulator of VEGF splicing. While both VEGF-A165a and VEGF-A165b isoforms were protective against AD-related neurotoxicity, measured by increased metabolic activity and neurite outgrowth, VEGF-A165a was able to enhance neurite outgrowth but VEGF-A165b did not. In contrast, VEGF-A165b was more effective than VEGF-A165a in preventing neurite "dieback" in a tau hyperphosphorylation model. SRPK1 inhibition was found to significantly protect against neurite "dieback" through shifting AS of VEGFA towards the VEGF-A165b isoform. These results indicate that controlling the activities of the two different isoforms could have therapeutic potential in Alzheimer's disease, but their effect may depend on the predominant mechanism of the neurotoxicity-tau or β-amyloid.
Collapse
Affiliation(s)
- Roaa H. Alalwany
- Tumour and Vascular Biology Laboratories, Division of Cancer and Stem Cells, Centre for Cancer Sciences, School of Medicine, Biodiscovery Institute, University of Nottingham, Nottingham, United Kingdom
| | - Tom Hawtrey
- School of Chemistry, University of New South Wales, Sydney, NSW, Australia
| | - Kevin Morgan
- School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Jonathan C. Morris
- School of Chemistry, University of New South Wales, Sydney, NSW, Australia
| | - Lucy F. Donaldson
- School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - David O. Bates
- Tumour and Vascular Biology Laboratories, Division of Cancer and Stem Cells, Centre for Cancer Sciences, School of Medicine, Biodiscovery Institute, University of Nottingham, Nottingham, United Kingdom
- Pan African Cancer Research Institute, University of Pretoria, Pretoria, South Africa
| |
Collapse
|
2
|
Go YJ, Kalathingal M, Rhee YM. Elucidating activation and deactivation dynamics of VEGFR-2 transmembrane domain with coarse-grained molecular dynamics simulations. PLoS One 2023; 18:e0281781. [PMID: 36795710 PMCID: PMC9934429 DOI: 10.1371/journal.pone.0281781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 02/01/2023] [Indexed: 02/17/2023] Open
Abstract
The vascular endothelial growth factor receptor 2 (VEGFR-2) is a member of receptor tyrosine kinases (RTKs) and is a dimeric membrane protein that functions as a primary regulator of angiogenesis. As is usual with RTKs, spatial alignment of its transmembrane domain (TMD) is essential toward VEGFR-2 activation. Experimentally, the helix rotations within TMD around their own helical axes are known to participate importantly toward the activation process in VEGFR-2, but the detailed dynamics of the interconversion between the active and inactive TMD forms have not been clearly elucidated at the molecular level. Here, we attempt to elucidate the process by using coarse grained (CG) molecular dynamics (MD) simulations. We observe that inactive dimeric TMD in separation is structurally stable over tens of microseconds, suggesting that TMD itself is passive and does not allow spontaneous signaling of VEGFR-2. By starting from the active conformation, we reveal the mechanism of TMD inactivation through analyzing the CG MD trajectories. We observe that interconversions between a left-handed overlay and a right-handed one are essential for the process of going from an active TMD structure to the inactive form. In addition, our simulations find that the helices can rotate properly when the overlaying structure of the helices interconverts and when the crossing angle of the two helices changes by larger than ~40 degrees. As the activation right after the ligand attachment on VEGFR-2 will take place in the reverse manner of this inactivation process, these structural aspects will also appear importantly for the activation process. The rather large change in helix configuration for activation also explains why VEGFR-2 rarely self-activate and how the activating ligand structurally drive the whole VEGFR-2. This mechanism of TMD activation / inactivation within VEGFR-2 may help in further understanding the overall activation processes of other RTKs.
Collapse
Affiliation(s)
- Yeon Ju Go
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Korea
| | - Mahroof Kalathingal
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Korea
- Department of Chemistry, Pohang University of Science and Technology (POSTECH), Pohang, Korea
| | - Young Min Rhee
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Korea
- * E-mail:
| |
Collapse
|
3
|
Depetris RS, Lu D, Polonskaya Z, Zhang Z, Luna X, Tankard A, Kolahi P, Drummond M, Williams C, Ebert MCCJC, Patel JP, Poyurovsky MV. Functional antibody characterization via direct structural analysis and information-driven protein-protein docking. Proteins 2021; 90:919-935. [PMID: 34773424 PMCID: PMC9544432 DOI: 10.1002/prot.26280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 08/28/2021] [Accepted: 11/07/2021] [Indexed: 12/02/2022]
Abstract
Detailed description of the mechanism of action of the therapeutic antibodies is essential for the functional characterization and future optimization of potential clinical agents. We recently developed KD035, a fully human antibody targeting vascular endothelial growth factor receptor 2 (VEGFR2). KD035 blocked VEGF‐A, and VEGF‐C‐mediated VEGFR2 activation, as demonstrated by the in vitro binding and competition assays and functional cellular assays. Here, we report a computational model of the complex between the variable fragment of KD035 (KD035(Fv)) and the domains 2 and 3 of the extracellular portion of VEGFR2 (VEGFR2(D2‐3)). Our modeling was guided by a priori experimental information including the X‐ray structures of KD035 and related antibodies, binding assays, target domain mapping and comparison of KD035 affinity for VEGFR2 from different species. The accuracy of the model was assessed by molecular dynamics simulations, and subsequently validated by mutagenesis and binding analysis. Importantly, the steps followed during the generation of this model can set a precedent for future in silico efforts aimed at the accurate description of the antibody–antigen and more broadly protein–protein complexes.
Collapse
Affiliation(s)
| | - Dan Lu
- Kadmon Corporation, LLC, New York, New York, USA
| | | | - Zhikai Zhang
- Kadmon Corporation, LLC, New York, New York, USA
| | - Xenia Luna
- Kadmon Corporation, LLC, New York, New York, USA
| | | | - Pegah Kolahi
- Kadmon Corporation, LLC, New York, New York, USA
| | | | | | | | | | | |
Collapse
|
4
|
Di Stasi R, Diana D, De Rosa L, Fattorusso R, D'Andrea LD. Biochemical and Conformational Characterization of Recombinant VEGFR2 Domain 7. Mol Biotechnol 2020; 61:860-872. [PMID: 31531759 DOI: 10.1007/s12033-019-00211-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Angiogenesis is a biological process finely tuned by a plethora of pro- and anti-angiogenic molecules, among which vascular endothelial growth factors (VEGFs). Their biological activity is expressed through the interaction with three cognate receptor tyrosine kinases, VEGFR1, 2, and 3. VEGFR2 is the primary regulator of angiogenesis. Ligand-induced VEGFR2 dimerization and activation depend on direct ligand binding to extracellular domains 2 and 3 of receptor and in the establishment of interactions between proximal membrane domains. VEGFR2 domain 7 has been shown to play a crucial role in receptor dimerization and regulation, therefore, representing a convenient target for the allosteric modulation of VEGFR2 activity. The ability to prepare a functional VEGFR2D7 domain represents the starting point to the development of novel VEGFR2 binders acting as allosteric inhibitors of receptor activity. Here, we describe a robust and efficient procedure for the preparation in E. coli of the VEGFR2 domain 7. The protein was obtained with a good yield and was properly folded. It was investigated in a biochemical and structural study, providing information on its conformational arrangement and in solution properties.
Collapse
Affiliation(s)
- Rossella Di Stasi
- Istituto di Biostrutture e Bioimmagini, CNR, Via Mezzocannone 16, 80134, Naples, Italy.
| | - Donatella Diana
- Istituto di Biostrutture e Bioimmagini, CNR, Via Mezzocannone 16, 80134, Naples, Italy
| | - Lucia De Rosa
- Istituto di Biostrutture e Bioimmagini, CNR, Via Mezzocannone 16, 80134, Naples, Italy
| | - Roberto Fattorusso
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università della Campania "L. Vanvitelli", Via Vivaldi, 43 - 81100, Caserta, Italy
| | - Luca D D'Andrea
- Istituto di Biostrutture e Bioimmagini, CNR, Via Mezzocannone 16, 80134, Naples, Italy.
- Istituto di Biostrutture e Bioimmagini, CNR, Via Nizza 52, 10126, Turin, Italy.
| |
Collapse
|
5
|
Di Stasi R, De Rosa L, Diana D, Fattorusso R, D'Andrea LD. Human Recombinant VEGFR2D4 Biochemical Characterization to Investigate Novel Anti-VEGFR2D4 Antibodies for Allosteric Targeting of VEGFR2. Mol Biotechnol 2019; 61:513-520. [PMID: 31025286 DOI: 10.1007/s12033-019-00181-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
VEGF-A/VEGFR2 complex is the major signaling pathway involved in angiogenesis and the inhibition of this axis retards tumor growth and inflammatory disorders progression, reducing vessel sprouting. Signaling by VEGFR2 requires receptor dimerization and a well-defined orientation of monomers in the active dimer. The extracellular portion of receptor is composed of seven Ig-like domains, of which D2-3 are the ligand binding domains, while D4 and D7, establishing homotypic contacts, allosterically regulate receptor activity. The allosteric targeting of VEGFR2 represents a promising alternative to study neovascular disorders overcoming drawbacks related to competition with VEGF. In this work, we expressed in bacterial host domain 4 of VEGFR2 (VEGFR2D4). After protein refolding, we characterized the purified domain and administered it in mice for monoclonal antibodies production. One of them, mAbD4, was tested in ELISA assays, showing a nanomolar affinity for VEGFR2D4. Finally, the methodology here described could contribute to the development of antibodies which can allosterically bind VEGFR2 and therefore to be used for imaging purposes or to modulate receptor signaling.
Collapse
Affiliation(s)
- Rossella Di Stasi
- Istituto di Biostrutture e Bioimmagini, CNR, Via Mezzocannone 16, 80134, Napoli, Italy
| | - Lucia De Rosa
- Istituto di Biostrutture e Bioimmagini, CNR, Via Mezzocannone 16, 80134, Napoli, Italy
| | - Donatella Diana
- Istituto di Biostrutture e Bioimmagini, CNR, Via Mezzocannone 16, 80134, Napoli, Italy
| | - Roberto Fattorusso
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università della Campania "L. Vanvitelli", Via Vivaldi, 43, 81100, Caserta, Italy
| | - Luca D D'Andrea
- Istituto di Biostrutture e Bioimmagini, CNR, Via Nizza 52, 10126, Torino, Italy.
| |
Collapse
|
6
|
VEGFR Recognition Interface of a Proangiogenic VEGF-Mimetic Peptide Determined In Vitro and in the Presence of Endothelial Cells by NMR Spectroscopy. Chemistry 2018; 24:11461-11466. [DOI: 10.1002/chem.201802117] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Indexed: 01/18/2023]
|
7
|
Ballmer-Hofer K, A C Hyde C, Schleier T, Avramovic D. ScFvs as Allosteric Inhibitors of VEGFR-2: Novel Tools to Harness VEGF Signaling. Int J Mol Sci 2018; 19:E1334. [PMID: 29723982 PMCID: PMC5983656 DOI: 10.3390/ijms19051334] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 04/23/2018] [Accepted: 04/23/2018] [Indexed: 01/04/2023] Open
Abstract
Vascular Endothelial Growth Factor Receptor 2 (VEGFR-2) is the main mediator of angiogenic signaling in endothelial cells and a primary responder to VEGF. VEGF dependent VEGFR-2 activation regulates endothelial cell migration and proliferation, as well as vessel permeability. VEGF is presented as an antiparallel homodimer, and its binding to VEGFR-2 brings two receptors in close proximity. Downstream signaling is triggered by receptor dimerization, kinase activation, and receptor internalization. Our aim was to further investigate allosteric inhibition using binders targeting extracellular subdomains 4⁻7 of VEGFR-2 as an alternative to existing anti-angiogenic therapies, which rely on neutralizing VEGF or blocking of the ligand-binding site on the receptor. We applied phage display technology to produce single chain antibody fragments (scFvs) targeting VEGFR-2. Selected antibody fragments were characterized using biophysical and biological assays. We characterized several antibody fragments, which exert their inhibitory effect of VEGFR-2 independent of ligand binding. These reagents led to rapid clearance of VEGFR-2 from the cell surface without kinase activation, followed by an increase in intracellular receptor-positive vesicles, suggesting receptor internalization. Our highly specific VEGFR-2 binders thus represent novel tools for anti-angiogenic therapy and diagnostic applications.
Collapse
Affiliation(s)
- Kurt Ballmer-Hofer
- Laboratory of Biomolecular Research, Paul Scherrer Institut, 5232 Villigen, Switzerland.
| | - Caroline A C Hyde
- Laboratory of Biomolecular Research, Paul Scherrer Institut, 5232 Villigen, Switzerland.
| | - Thomas Schleier
- Laboratory of Biomolecular Research, Paul Scherrer Institut, 5232 Villigen, Switzerland.
| | - Dragana Avramovic
- Laboratory of Biomolecular Research, Paul Scherrer Institut, 5232 Villigen, Switzerland.
| |
Collapse
|
8
|
Peach CJ, Mignone VW, Arruda MA, Alcobia DC, Hill SJ, Kilpatrick LE, Woolard J. Molecular Pharmacology of VEGF-A Isoforms: Binding and Signalling at VEGFR2. Int J Mol Sci 2018; 19:E1264. [PMID: 29690653 PMCID: PMC5979509 DOI: 10.3390/ijms19041264] [Citation(s) in RCA: 259] [Impact Index Per Article: 43.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 04/14/2018] [Accepted: 04/16/2018] [Indexed: 02/07/2023] Open
Abstract
Vascular endothelial growth factor-A (VEGF-A) is a key mediator of angiogenesis, signalling via the class IV tyrosine kinase receptor family of VEGF Receptors (VEGFRs). Although VEGF-A ligands bind to both VEGFR1 and VEGFR2, they primarily signal via VEGFR2 leading to endothelial cell proliferation, survival, migration and vascular permeability. Distinct VEGF-A isoforms result from alternative splicing of the Vegfa gene at exon 8, resulting in VEGFxxxa or VEGFxxxb isoforms. Alternative splicing events at exons 5⁻7, in addition to recently identified posttranslational read-through events, produce VEGF-A isoforms that differ in their bioavailability and interaction with the co-receptor Neuropilin-1. This review explores the molecular pharmacology of VEGF-A isoforms at VEGFR2 in respect to ligand binding and downstream signalling. To understand how VEGF-A isoforms have distinct signalling despite similar affinities for VEGFR2, this review re-evaluates the typical classification of these isoforms relative to the prototypical, “pro-angiogenic” VEGF165a. We also examine the molecular mechanisms underpinning the regulation of VEGF-A isoform signalling and the importance of interactions with other membrane and extracellular matrix proteins. As approved therapeutics targeting the VEGF-A/VEGFR signalling axis largely lack long-term efficacy, understanding these isoform-specific mechanisms could aid future drug discovery efforts targeting VEGF receptor pharmacology.
Collapse
Affiliation(s)
- Chloe J Peach
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK.
- Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands NG7 2UH, UK.
| | - Viviane W Mignone
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK.
- Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands NG7 2UH, UK.
- CAPES-University of Nottingham Programme in Drug Discovery, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK.
| | - Maria Augusta Arruda
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK.
- Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands NG7 2UH, UK.
- CAPES-University of Nottingham Programme in Drug Discovery, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK.
| | - Diana C Alcobia
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK.
- Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands NG7 2UH, UK.
| | - Stephen J Hill
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK.
- Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands NG7 2UH, UK.
| | - Laura E Kilpatrick
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK.
- Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands NG7 2UH, UK.
| | - Jeanette Woolard
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK.
- Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands NG7 2UH, UK.
| |
Collapse
|
9
|
King C, Wirth D, Workman S, Hristova K. Cooperative interactions between VEGFR2 extracellular Ig-like subdomains ensure VEGFR2 dimerization. Biochim Biophys Acta Gen Subj 2017; 1861:2559-2567. [PMID: 28847506 DOI: 10.1016/j.bbagen.2017.08.021] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 08/16/2017] [Accepted: 08/24/2017] [Indexed: 01/02/2023]
Abstract
BACKGROUND Prior studies have suggested that the interactions occurring between VEGFR2 extracellular domains in the absence of ligand are complex. Here we seek novel insights into these interactions, and into the role of the different Ig-like domains (D1 through D7) in VEGFR2 dimerization. METHODS We study the dimerization of a single amino acid mutant and of three deletion mutants in the plasma membrane using two photon microscopy and fully quantified spectral imaging. RESULTS We demonstrate that a set of cooperative interactions between the different Ig-like domains ensure that VEGFR2 dimerizes with a specific affinity instead of forming oligomers. CONCLUSIONS The contributions of subunits D7 and D4 seem to be the most critical, as they appear essential for strong lateral interactions and for the formation of dimers, respectively. GENERAL SIGNIFICANCE This study provides new insights into the mechanism of VEGFR2 dimerization and activation.
Collapse
Affiliation(s)
- Christopher King
- Program in Molecular Biophysics, Johns Hopkins University, Baltimore, MD 21218, United States
| | - Daniel Wirth
- Department of Materials Science and Engineering, Institute for NanoBioTechnology, Johns Hopkins University, Baltimore, MD 21218, United States
| | - Samuel Workman
- Department of Materials Science and Engineering, Institute for NanoBioTechnology, Johns Hopkins University, Baltimore, MD 21218, United States
| | - Kalina Hristova
- Department of Materials Science and Engineering, Institute for NanoBioTechnology, Johns Hopkins University, Baltimore, MD 21218, United States; Program in Molecular Biophysics, Johns Hopkins University, Baltimore, MD 21218, United States.
| |
Collapse
|
10
|
Kilpatrick LE, Friedman-Ohana R, Alcobia DC, Riching K, Peach CJ, Wheal AJ, Briddon SJ, Robers MB, Zimmerman K, Machleidt T, Wood KV, Woolard J, Hill SJ. Real-time analysis of the binding of fluorescent VEGF 165a to VEGFR2 in living cells: Effect of receptor tyrosine kinase inhibitors and fate of internalized agonist-receptor complexes. Biochem Pharmacol 2017; 136:62-75. [PMID: 28392095 PMCID: PMC5457915 DOI: 10.1016/j.bcp.2017.04.006] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2016] [Accepted: 04/04/2017] [Indexed: 01/01/2023]
Abstract
Vascular endothelial growth factor (VEGF) is an important mediator of angiogenesis. Here we have used a novel stoichiometric protein-labeling method to generate a fluorescent variant of VEGF (VEGF165a-TMR) labeled on a single cysteine within each protomer of the antiparallel VEGF homodimer. VEGF165a-TMR has then been used in conjunction with full length VEGFR2, tagged with the bioluminescent protein NanoLuc, to undertake a real time quantitative evaluation of VEGFR2 binding characteristics in living cells using bioluminescence resonance energy transfer (BRET). This provided quantitative information on VEGF-VEGFR2 interactions. At longer incubation times, VEGFR2 is internalized by VEGF165a-TMR into intracellular endosomes. This internalization can be prevented by the receptor tyrosine kinase inhibitors (RTKIs) cediranib, sorafenib, pazopanib or vandetanib. In the absence of RTKIs, the BRET signal is decreased over time as a consequence of the dissociation of agonist from the receptor in intracellular endosomes and recycling of VEGFR2 back to the plasma membrane.
Collapse
Affiliation(s)
- Laura E Kilpatrick
- Cell Signalling and Pharmacology Research Group, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | | | - Diana C Alcobia
- Cell Signalling and Pharmacology Research Group, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | | | - Chloe J Peach
- Cell Signalling and Pharmacology Research Group, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Amanda J Wheal
- Cell Signalling and Pharmacology Research Group, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Stephen J Briddon
- Cell Signalling and Pharmacology Research Group, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | | | | | | | | | - Jeanette Woolard
- Cell Signalling and Pharmacology Research Group, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom.
| | - Stephen J Hill
- Cell Signalling and Pharmacology Research Group, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom.
| |
Collapse
|
11
|
Immunoglobulin-like domain 4-mediated ligand-independent dimerization triggers VEGFR-2 activation in HUVECs and VEGFR2-positive breast cancer cells. Breast Cancer Res Treat 2017; 163:423-434. [PMID: 28303365 DOI: 10.1007/s10549-017-4189-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Accepted: 03/06/2017] [Indexed: 02/07/2023]
Abstract
PURPOSE The extracellular region (EC) of the vascular endothelial growth factor (VEGF) receptor-2 (VEGFR-2) contains seven immunoglobulin-like (Ig-like) domains that are required for specific ligand binding and receptor dimerization. Studies of domain 4-7 deletions and substitutions provided insights into the interaction between receptors in the absence of VEGF. In this study, we investigated the effect of domain 4 in ligand-independent VEGFR-2 dimerization and activation in human vascular endothelial cells and human breast cancer cells. METHODS To confirm the role of domain 4 in ligand-independent receptor dimerization and activation, two VEGFR-2 fragments with and without domain 4, KFP1 and KFP2, were generated by recombinant DNA technology. We measured the affinity of KFP1 and KFP2 with VEGFR-2, and the roles of KFP1 and FKP2 in dimerization and phosphorylation of VEGFR-2. We also evaluated the effect of KFP1 and FKP2 on cell proliferation and migration in HUVECs and in human breast cancer cells. RESULTS We showed that KFP1 did not affect the interaction of VEGFR-2 and VEGF but bound VEGFR-2 in the absence of VEGF. Furthermore, cross-linking and cross-linking immunoblotting demonstrated that KFP1 could form a complex with VEGFR-2, which resulted in VEGFR-2 dimerization in the absence of VEGF. Importantly, we found that the KDR fragment with domain 4 induced phosphorylation of VEGFR-2, as well as phosphorylation of downstream receptor kinases in HUVECs and VEGFR-2-positive breast cancer cells. Consistent with these results, this ligand-independent activation of VEGFR-2 also promoted downstream signaling and cell proliferation and migration. CONCLUSIONS The domain 4 of VEGFR-2 plays an important role in the interaction between VEGFR receptors in the absence of VEGF.
Collapse
|
12
|
Structure of the Full-length VEGFR-1 Extracellular Domain in Complex with VEGF-A. Structure 2017; 25:341-352. [DOI: 10.1016/j.str.2016.12.012] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2016] [Revised: 11/14/2016] [Accepted: 12/21/2016] [Indexed: 12/27/2022]
|
13
|
Chandler KB, Leon DR, Meyer RD, Rahimi N, Costello CE. Site-Specific N-Glycosylation of Endothelial Cell Receptor Tyrosine Kinase VEGFR-2. J Proteome Res 2016; 16:677-688. [PMID: 27966990 DOI: 10.1021/acs.jproteome.6b00738] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Vascular endothelial growth factor receptor-2 (VEGFR-2) is an important receptor tyrosine kinase (RTK) that plays critical roles in both physiologic and pathologic angiogenesis. The extracellular domain of VEGFR-2 is composed of seven immunoglobulin-like domains, each with multiple potential N-glycosylation sites (sequons). N-glycosylation plays a central role in RTK ligand binding, trafficking, and stability. However, despite its importance, the functional role of N-glycosylation of VEGFR-2 remains poorly understood. The objectives of the present study were to characterize N-glycosylation sites in VEGFR-2 via enzymatic release of the glycans and concomitant incorporation of 18O into formerly N-glycosylated sites followed by tandem mass spectrometry (MS/MS) analysis to determine N-glycosylation site occupancy and the site-specific N-glycan heterogeneity of VEGFR-2 glycopeptides. The data demonstrated that all seven VEGFR-2 immunoglobulin-like domains have at least one occupied N-glycosylation site. MS/MS analyses of glycopeptides and deamidated, deglycosylated (PNGase F-treated) peptides from ectopically expressed VEGFR-2 in porcine aortic endothelial (PAE) cells identified N-glycans at the majority of the 17 potential N-glycosylation sites on VEGFR-2 in a site-specific manner. The data presented here provide direct evidence for site-specific, heterogeneous N-glycosylation and N-glycosylation site occupancy on VEGFR-2. The study has important implications for the therapeutic targeting of VEGFR-2, ligand binding, trafficking, and signaling.
Collapse
Affiliation(s)
- Kevin Brown Chandler
- Center for Biomedical Mass Spectrometry, Department of Biochemistry and ‡Department of Pathology and Laboratory Medicine, Boston University School of Medicine , Boston, Massachusetts 02118, United States
| | - Deborah R Leon
- Center for Biomedical Mass Spectrometry, Department of Biochemistry and ‡Department of Pathology and Laboratory Medicine, Boston University School of Medicine , Boston, Massachusetts 02118, United States
| | - Rosana D Meyer
- Center for Biomedical Mass Spectrometry, Department of Biochemistry and ‡Department of Pathology and Laboratory Medicine, Boston University School of Medicine , Boston, Massachusetts 02118, United States
| | - Nader Rahimi
- Center for Biomedical Mass Spectrometry, Department of Biochemistry and ‡Department of Pathology and Laboratory Medicine, Boston University School of Medicine , Boston, Massachusetts 02118, United States
| | - Catherine E Costello
- Center for Biomedical Mass Spectrometry, Department of Biochemistry and ‡Department of Pathology and Laboratory Medicine, Boston University School of Medicine , Boston, Massachusetts 02118, United States
| |
Collapse
|
14
|
Structural basis for misregulation of kinesin KIF21A autoinhibition by CFEOM1 disease mutations. Sci Rep 2016; 6:30668. [PMID: 27485312 PMCID: PMC4971492 DOI: 10.1038/srep30668] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Accepted: 07/08/2016] [Indexed: 11/09/2022] Open
Abstract
Tight regulation of kinesin activity is crucial and malfunction is linked to neurological diseases. Point mutations in the KIF21A gene cause congenital fibrosis of the extraocular muscles type 1 (CFEOM1) by disrupting the autoinhibitory interaction between the motor domain and a regulatory region in the stalk. However, the molecular mechanism underlying the misregulation of KIF21A activity in CFEOM1 is not understood. Here, we show that the KIF21A regulatory domain containing all disease-associated substitutions in the stalk forms an intramolecular antiparallel coiled coil that inhibits the kinesin. CFEOM1 mutations lead to KIF21A hyperactivation by affecting either the structural integrity of the antiparallel coiled coil or the autoinhibitory binding interface, thereby reducing its affinity for the motor domain. Interaction of the KIF21A regulatory domain with the KIF21B motor domain and sequence similarities to KIF7 and KIF27 strongly suggest a conservation of this regulatory mechanism in other kinesin-4 family members.
Collapse
|
15
|
Sarabipour S, Ballmer-Hofer K, Hristova K. VEGFR-2 conformational switch in response to ligand binding. eLife 2016; 5:e13876. [PMID: 27052508 PMCID: PMC4829425 DOI: 10.7554/elife.13876] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 03/09/2016] [Indexed: 01/02/2023] Open
Abstract
VEGFR-2 is the primary regulator of angiogenesis, the development of new blood vessels from pre-existing ones. VEGFR-2 has been hypothesized to be monomeric in the absence of bound ligand, and to undergo dimerization and activation only upon ligand binding. Using quantitative FRET and biochemical analysis, we show that VEGFR-2 forms dimers also in the absence of ligand when expressed at physiological levels, and that these dimers are phosphorylated. Ligand binding leads to a change in the TM domain conformation, resulting in increased kinase domain phosphorylation. Inter-receptor contacts within the extracellular and TM domains are critical for the establishment of the unliganded dimer structure, and for the transition to the ligand-bound active conformation. We further show that the pathogenic C482R VEGFR-2 mutant, linked to infantile hemangioma, promotes ligand-independent signaling by mimicking the structure of the ligand-bound wild-type VEGFR-2 dimer.
Collapse
Affiliation(s)
- Sarvenaz Sarabipour
- Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, United States
| | - Kurt Ballmer-Hofer
- Laboratory of Biomolecular Research, Molecular Cell Biology, Paul Scherrer Institute, Villigen, Switzerland
| | - Kalina Hristova
- Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, United States
| |
Collapse
|
16
|
Lu X, Sun X. Profile of conbercept in the treatment of neovascular age-related macular degeneration. DRUG DESIGN DEVELOPMENT AND THERAPY 2015; 9:2311-20. [PMID: 25960634 PMCID: PMC4410828 DOI: 10.2147/dddt.s67536] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
In developed countries, age-related macular degeneration (AMD) is the leading cause of irreversible blindness in individuals over the age of 65 years. Vascular endothelial growth factor (VEGF) plays a vital role in the formation of neovascular AMD. VEGF regulates angiogenesis, enhances vascular permeability, and drives the formation of choroidal neovascularization. As a result of the introduction of anti-VEGF drugs, the incidence of blindness from neovascular AMD has greatly reduced. Anti-VEGF drugs are used as a first-line treatment for neovascular AMD. The most recent anti-VEGF drug is conbercept, also named KH902, which was approved for the treatment of neovascular AMD by the China Food and Drug Administration in December 2013. In this review, recent clinical information regarding the use of conbercept to treat neovascular AMD is summarized. Conbercept is a soluble receptor decoy that blocks all isoforms of VEGF-A, VEGF-B, VEGF-C, and PlGF, which has a high binding affinity to VEGF and a long half-life in vitreous. Preclinical studies have demonstrated its anti-angiogenesis activity in both ocular neovascular disease models and tumor models. Clinical trials of conbercept have shown its superior efficacy and safety. Patients respond well even with 3-month treatment intervals following loading doses once a month for 3 months. The potential therapeutic effect of conbercept on the treatment of polypoidal choroidal vasculopathy, a special type of neovascular AMD, is also promising. In summary, conbercept is a new treatment option for ophthalmologists and their patients and may help address the limitations of current anti-VEGF drugs.
Collapse
Affiliation(s)
- Xinmin Lu
- Department of Ophthalmology, Shanghai First People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People's Republic of China
| | - Xiaodong Sun
- Department of Ophthalmology, Shanghai First People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People's Republic of China ; Eye Research Institute of Shanghai Jiao Tong University, Shanghai, People's Republic of China ; Shanghai Key Laboratory of Fundus Disease, Shanghai, People's Republic of China
| |
Collapse
|
17
|
Hulse RP, Beazley-Long N, Hua J, Kennedy H, Prager J, Bevan H, Qiu Y, Fernandes ES, Gammons MV, Ballmer-Hofer K, Gittenberger de Groot AC, Churchill AJ, Harper SJ, Brain SD, Bates DO, Donaldson LF. Regulation of alternative VEGF-A mRNA splicing is a therapeutic target for analgesia. Neurobiol Dis 2014; 71:245-59. [PMID: 25151644 PMCID: PMC4194316 DOI: 10.1016/j.nbd.2014.08.012] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Revised: 07/29/2014] [Accepted: 08/06/2014] [Indexed: 12/02/2022] Open
Abstract
Vascular endothelial growth factor-A (VEGF-A) is best known as a key regulator of the formation of new blood vessels. Neutralization of VEGF-A with anti-VEGF therapy e.g. bevacizumab, can be painful, and this is hypothesized to result from a loss of VEGF-A-mediated neuroprotection. The multiple vegf-a gene products consist of two alternatively spliced families, typified by VEGF-A165a and VEGF-A165b (both contain 165 amino acids), both of which are neuroprotective. Under pathological conditions, such as in inflammation and cancer, the pro-angiogenic VEGF-A165a is upregulated and predominates over the VEGF-A165b isoform. We show here that in rats and mice VEGF-A165a and VEGF-A165b have opposing effects on pain, and that blocking the proximal splicing event – leading to the preferential expression of VEGF-A165b over VEGF165a – prevents pain in vivo. VEGF-A165a sensitizes peripheral nociceptive neurons through actions on VEGFR2 and a TRPV1-dependent mechanism, thus enhancing nociceptive signaling. VEGF-A165b blocks the effect of VEGF-A165a. After nerve injury, the endogenous balance of VEGF-A isoforms switches to greater expression of VEGF-Axxxa compared to VEGF-Axxxb, through an SRPK1-dependent pre-mRNA splicing mechanism. Pharmacological inhibition of SRPK1 after traumatic nerve injury selectively reduced VEGF-Axxxa expression and reversed associated neuropathic pain. Exogenous VEGF-A165b also ameliorated neuropathic pain. We conclude that the relative levels of alternatively spliced VEGF-A isoforms are critical for pain modulation under both normal conditions and in sensory neuropathy. Altering VEGF-Axxxa/VEGF-Axxxb balance by targeting alternative RNA splicing may be a new analgesic strategy. The different vegf-a splice variants, VEGF-A165a and VEGF-A165b have pro- and anti-nociceptive actions respectively. Pro-nociceptive actions of VEGF-A165a are dependent on TRPV1. Alternative pre-mRNA splicing underpins peripheral sensitization by VEGF-A isoforms in normal and neuropathic animals.
Collapse
Affiliation(s)
- R P Hulse
- Physiology and Pharmacology, University of Bristol, Bristol BS8 1TD, UK; Cancer Biology, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Queen's Medical Centre, Nottingham NG2 7UH, UK
| | - N Beazley-Long
- Physiology and Pharmacology, University of Bristol, Bristol BS8 1TD, UK; School of Life Sciences, The Medical School, University of Nottingham, Queen's Medical Centre, Nottingham NG2 7UH, UK
| | - J Hua
- Physiology and Pharmacology, University of Bristol, Bristol BS8 1TD, UK
| | - H Kennedy
- Physiology and Pharmacology, University of Bristol, Bristol BS8 1TD, UK
| | - J Prager
- Physiology and Pharmacology, University of Bristol, Bristol BS8 1TD, UK
| | - H Bevan
- Physiology and Pharmacology, University of Bristol, Bristol BS8 1TD, UK
| | - Y Qiu
- Physiology and Pharmacology, University of Bristol, Bristol BS8 1TD, UK
| | | | - M V Gammons
- Physiology and Pharmacology, University of Bristol, Bristol BS8 1TD, UK
| | | | | | - A J Churchill
- Clinical Sciences, University of Bristol, Bristol BS1 2LX, UK
| | - S J Harper
- Physiology and Pharmacology, University of Bristol, Bristol BS8 1TD, UK
| | - S D Brain
- King's College London, London SE1 9NH, UK
| | - D O Bates
- Cancer Biology, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Queen's Medical Centre, Nottingham NG2 7UH, UK.
| | - L F Donaldson
- Physiology and Pharmacology, University of Bristol, Bristol BS8 1TD, UK; School of Life Sciences, The Medical School, University of Nottingham, Queen's Medical Centre, Nottingham NG2 7UH, UK.
| |
Collapse
|
18
|
Manni S, Kisko K, Schleier T, Missimer J, Ballmer-Hofer K. Functional and structural characterization of the kinase insert and the carboxy terminal domain in VEGF receptor 2 activation. FASEB J 2014; 28:4914-23. [PMID: 25114179 DOI: 10.1096/fj.14-256206] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Vascular endothelial growth factors (VEGFs) regulate blood and lymphatic vessel development and homeostasis. VEGF receptor 2 (VEGFR-2) is the major receptor involved in vasculogenesis and angiogenesis and regulates endothelial cell survival, migration, and mitogenesis. Ligand-mediated receptor dimerization instigates transmembrane signaling, thereby promoting activation of the intracellular kinase domain. The intracellular part of the receptor comprises the juxtamembrane domain, the catalytic kinase domain, the kinase insert domain (KID), and the carboxy terminal domain (CD). Here we show that the CD inhibits VEGFR-2 activity in the absence of ligand, whereas the KID, particularly a tyrosine residue in this domain (Y951), is indispensable for downstream signaling by the activated kinase. Because of the lack of crystallographic data for the complete kinase domain, we applied size-exclusion chromatography, multiangle laser scattering, analytical ultracentrifugation, and small-angle X-ray scattering to build and functionally validate structural models. Our data show substantial conformational changes of the kinase when it is switched from the inactive, unphosphorylated state to the active, phosphorylated state. Finally, we structurally characterized recombinantly produced protein complexes between VEGFR-2 and T cell-specific adapter protein, a molecule involved in downstream signaling by VEGFR-2.
Collapse
Affiliation(s)
- Sandro Manni
- Biomolecular Research, Molecular Cell Biology, Paul Scherrer Institute, Villigen, Switzerland
| | - Kaisa Kisko
- Biomolecular Research, Molecular Cell Biology, Paul Scherrer Institute, Villigen, Switzerland
| | - Thomas Schleier
- Biomolecular Research, Molecular Cell Biology, Paul Scherrer Institute, Villigen, Switzerland
| | - Jack Missimer
- Biomolecular Research, Molecular Cell Biology, Paul Scherrer Institute, Villigen, Switzerland
| | - Kurt Ballmer-Hofer
- Biomolecular Research, Molecular Cell Biology, Paul Scherrer Institute, Villigen, Switzerland
| |
Collapse
|
19
|
Manni S, Mineev KS, Usmanova D, Lyukmanova EN, Shulepko MA, Kirpichnikov MP, Winter J, Matkovic M, Deupi X, Arseniev AS, Ballmer-Hofer K. Structural and functional characterization of alternative transmembrane domain conformations in VEGF receptor 2 activation. Structure 2014; 22:1077-1089. [PMID: 24980797 DOI: 10.1016/j.str.2014.05.010] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Revised: 05/16/2014] [Accepted: 05/17/2014] [Indexed: 10/25/2022]
Abstract
Transmembrane signaling by receptor tyrosine kinases (RTKs) entails ligand-mediated dimerization and structural rearrangement of the extracellular domains. RTK activation also depends on the specific orientation of the transmembrane domain (TMD) helices, as suggested by pathogenic, constitutively active RTK mutants. Such mutant TMDs carry polar amino acids promoting stable transmembrane helix dimerization, which is essential for kinase activation. We investigated the effect of polar amino acids introduced into the TMD of vascular endothelial growth factor receptor 2, regulating blood vessel homeostasis. Two mutants showed constitutive kinase activity, suggesting that precise TMD orientation is mandatory for kinase activation. Nuclear magnetic resonance spectroscopy revealed that TMD helices in activated constructs were rotated by 180° relative to the interface of the wild-type conformation, confirming that ligand-mediated receptor activation indeed results from transmembrane helix rearrangement. A molecular dynamics simulation confirmed the transmembrane helix arrangement of wild-type and mutant TMDs revealed by nuclear magnetic resonance spectroscopy.
Collapse
Affiliation(s)
- Sandro Manni
- Paul Scherrer Institute, Biomolecular Research, 5232 Villigen PSI, Switzerland
| | - Konstantin S Mineev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Miklukho-Maklaya Street 16/10, Moscow 117997, Russian Federation
| | - Dinara Usmanova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Miklukho-Maklaya Street 16/10, Moscow 117997, Russian Federation; Moscow Institute of Physics and Technology, Institutskiy Pereulok 9, Dolgoprudny, Moscow Region 141700, Russian Federation
| | - Ekaterina N Lyukmanova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Miklukho-Maklaya Street 16/10, Moscow 117997, Russian Federation
| | - Mikhail A Shulepko
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Miklukho-Maklaya Street 16/10, Moscow 117997, Russian Federation; Lomonosov Moscow State University, Leninskie Gori 1, Moscow 119234, Russian Federation
| | - Mikhail P Kirpichnikov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Miklukho-Maklaya Street 16/10, Moscow 117997, Russian Federation; Lomonosov Moscow State University, Leninskie Gori 1, Moscow 119234, Russian Federation
| | - Jonas Winter
- Paul Scherrer Institute, Biomolecular Research, 5232 Villigen PSI, Switzerland
| | - Milos Matkovic
- Paul Scherrer Institute, Biomolecular Research, 5232 Villigen PSI, Switzerland
| | - Xavier Deupi
- Paul Scherrer Institute, Biomolecular Research, 5232 Villigen PSI, Switzerland; Paul Scherrer Institute, Condensed Matter Theory Group, 5232 Villigen PSI, Switzerland
| | - Alexander S Arseniev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Miklukho-Maklaya Street 16/10, Moscow 117997, Russian Federation; Moscow Institute of Physics and Technology, Institutskiy Pereulok 9, Dolgoprudny, Moscow Region 141700, Russian Federation
| | - Kurt Ballmer-Hofer
- Paul Scherrer Institute, Biomolecular Research, 5232 Villigen PSI, Switzerland.
| |
Collapse
|
20
|
Sharma V, Köllmer M, Szymusiak M, Nitsche LC, Gemeinhart RA, Liu Y. Toroidal-spiral particles for codelivery of anti-VEGFR-2 antibody and irinotecan: a potential implant to hinder recurrence of glioblastoma multiforme. Biomacromolecules 2014; 15:756-62. [PMID: 24460101 PMCID: PMC3983134 DOI: 10.1021/bm401550r] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Revised: 01/23/2014] [Indexed: 12/25/2022]
Abstract
Heterogeneous toroidal-spiral particles (TSPs) were generated by polymer droplet sedimentation, interaction, and cross-linking. TSPs provide a platform for encapsulation and release of multiple compounds of different sizes and physicochemical properties. As a model system, we demonstrate the encapsulation and independently controlled release of an anti-VEGFR-2 antibody and irinotecan for the treatment of glioblastoma multiforme. The anti-VEGFR-2 antibody was released from the TS channels and its binding to HUVECs was confirmed by confocal microscopy and flow cytometry, suggesting active antibody encapsulation and release. Irinotecan, a small molecule drug, was released from the dense polymer matrix of poly(ethylene glycol) diacrylate (MW ~ 700 g/mol; PEGDA 700). Released irinotecan inhibited the proliferation of U251 malignant glioma cells. Since the therapeutic compounds are released through different pathways, specifically diffusion through the polymer matrix versus TS channels, the release rate can be controlled independently through the design of the structure and material of particle components.
Collapse
Affiliation(s)
- Vishal Sharma
- Department of Chemical Engineering and Department of Bioengineering, University of Illinois at Chicago, Chicago, Illinois 60607, United States
| | - Melanie Köllmer
- Department of Biopharmaceutical Sciences and Department of Ophthalmology and Visual
Sciences, University of Illinois, Chicago, Illinois 60612, United States
| | - Magdalena Szymusiak
- Department of Chemical Engineering and Department of Bioengineering, University of Illinois at Chicago, Chicago, Illinois 60607, United States
| | - Ludwig C. Nitsche
- Department of Chemical Engineering and Department of Bioengineering, University of Illinois at Chicago, Chicago, Illinois 60607, United States
| | - Richard A. Gemeinhart
- Department of Chemical Engineering and Department of Bioengineering, University of Illinois at Chicago, Chicago, Illinois 60607, United States
- Department of Biopharmaceutical Sciences and Department of Ophthalmology and Visual
Sciences, University of Illinois, Chicago, Illinois 60612, United States
| | - Ying Liu
- Department of Chemical Engineering and Department of Bioengineering, University of Illinois at Chicago, Chicago, Illinois 60607, United States
- Department of Biopharmaceutical Sciences and Department of Ophthalmology and Visual
Sciences, University of Illinois, Chicago, Illinois 60612, United States
| |
Collapse
|
21
|
Lysine-specific chemical cross-linking of protein complexes and identification of cross-linking sites using LC-MS/MS and the xQuest/xProphet software pipeline. Nat Protoc 2013; 9:120-37. [DOI: 10.1038/nprot.2013.168] [Citation(s) in RCA: 200] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
22
|
Structural and mechanistic insights into VEGF receptor 3 ligand binding and activation. Proc Natl Acad Sci U S A 2013; 110:12960-5. [PMID: 23878260 DOI: 10.1073/pnas.1301415110] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Vascular endothelial growth factors (VEGFs) and their receptors (VEGFRs) are key drivers of blood and lymph vessel formation in development, but also in several pathological processes. VEGF-C signaling through VEGFR-3 promotes lymphangiogenesis, which is a clinically relevant target for treating lymphatic insufficiency and for blocking tumor angiogenesis and metastasis. The extracellular domain of VEGFRs consists of seven Ig homology domains; domains 1-3 (D1-3) are responsible for ligand binding, and the membrane-proximal domains 4-7 (D4-7) are involved in structural rearrangements essential for receptor dimerization and activation. Here we analyzed the crystal structures of VEGF-C in complex with VEGFR-3 domains D1-2 and of the VEGFR-3 D4-5 homodimer. The structures revealed a conserved ligand-binding interface in D2 and a unique mechanism for VEGFR dimerization and activation, with homotypic interactions in D5. Mutation of the conserved residues mediating the D5 interaction (Thr446 and Lys516) and the D7 interaction (Arg737) compromised VEGF-C induced VEGFR-3 activation. A thermodynamic analysis of VEGFR-3 deletion mutants showed that D3, D4-5, and D6-7 all contribute to ligand binding. A structural model of the VEGF-C/VEGFR-3 D1-7 complex derived from small-angle X-ray scattering data is consistent with the homotypic interactions in D5 and D7. Taken together, our data show that ligand-dependent homotypic interactions in D5 and D7 are essential for VEGFR activation, opening promising possibilities for the design of VEGFR-specific drugs.
Collapse
|
23
|
Anisimov A, Leppanen VM, Tvorogov D, Zarkada G, Jeltsch M, Holopainen T, Kaijalainen S, Alitalo K. The Basis for the Distinct Biological Activities of Vascular Endothelial Growth Factor Receptor-1 Ligands. Sci Signal 2013; 6:ra52. [DOI: 10.1126/scisignal.2003905] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
|
24
|
Nakayama M, Berger P. Coordination of VEGF receptor trafficking and signaling by coreceptors. Exp Cell Res 2013; 319:1340-7. [PMID: 23499743 DOI: 10.1016/j.yexcr.2013.03.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Revised: 02/25/2013] [Accepted: 03/02/2013] [Indexed: 02/01/2023]
Abstract
During development, regeneration and in certain pathological settings, the vasculature is expanded and remodeled substantially. Proper morphogenesis and function of blood vessels are essential in multicellular organisms. Upon stimulation with growth factors including vascular endothelial growth factors (VEGFs), the activation, internalization and sorting of receptor tyrosine kinases (RTKs) orchestrate developmental processes and the homeostatic maintenance of all organs including the vasculature. Previously, RTK signaling was thought to occur exclusively at the plasma membrane, a process that was subsequently terminated by endocytosis and receptor degradation. However, this model turned out to be an oversimplification and there is now a substantial amount of reports indicating that receptor internalization and trafficking to intracellular compartments depends on coreceptors leading to the activation of specific signaling pathways. Here we review the latest findings concerning endocytosis and intracellular trafficking of VEGFRs. The body of evidence is compelling that VEGF receptor trafficking is coordinated with other proteins such as Neuropilin-1, ephrin-B2, VE-cadherin and protein phosphatases.
Collapse
Affiliation(s)
- Masanori Nakayama
- Max-Planck-Institute for Molecular Biomedicine, Department of Tissue Morphogenesis, D-48149 Münster, Germany
| | | |
Collapse
|
25
|
Felix J, Elegheert J, Gutsche I, Shkumatov AV, Wen Y, Bracke N, Pannecoucke E, Vandenberghe I, Devreese B, Svergun DI, Pauwels E, Vergauwen B, Savvides SN. Human IL-34 and CSF-1 establish structurally similar extracellular assemblies with their common hematopoietic receptor. Structure 2013; 21:528-39. [PMID: 23478061 DOI: 10.1016/j.str.2013.01.018] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2012] [Revised: 01/22/2013] [Accepted: 01/28/2013] [Indexed: 12/21/2022]
Abstract
The discovery that hematopoietic human colony stimulating factor-1 receptor (CSF-1R) can be activated by two distinct cognate cytokines, colony stimulating factor-1 (CSF-1) and interleukin-34 (IL-34), created puzzling scenarios for the two possible signaling complexes. We here employ a hybrid structural approach based on small-angle X-ray scattering (SAXS) and negative-stain EM to reveal that bivalent binding of human IL-34 to CSF-1R leads to an extracellular assembly hallmarked by striking similarities to the CSF-1:CSF-1R complex, including homotypic receptor-receptor interactions. Thus, IL-34 and CSF-1 have evolved to exploit the geometric requirements of CSF-1R activation. Our models include N-linked oligomannose glycans derived from a systematic approach resulting in the accurate fitting of glycosylated models to the SAXS data. We further show that the C-terminal region of IL-34 is heavily glycosylated and that it can be proteolytically cleaved from the IL-34:hCSF-1R complex, providing insights into its role in the functional nonredundancy of IL-34 and CSF-1.
Collapse
Affiliation(s)
- Jan Felix
- Unit for Structural Biology, Laboratory for Protein Biochemistry and Biomolecular Engineering (L-ProBE), Ghent University, K.L. Ledeganckstraat 35, 9000 Ghent, Belgium
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
26
|
Seyednejad H, Ji W, Yang F, van Nostrum CF, Vermonden T, van den Beucken JJ, Dhert WJ, Hennink WE, Jansen JA. Coaxially Electrospun Scaffolds Based on Hydroxyl-Functionalized Poly(ε-caprolactone) and Loaded with VEGF for Tissue Engineering Applications. Biomacromolecules 2012; 13:3650-60. [DOI: 10.1021/bm301101r] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Hajar Seyednejad
- Department of Pharmaceutics,
Utrecht Institute for Pharmaceutical Sciences (UIPS), Faculty of Science, Utrecht University, P.O. Box 80082, 3508 TB Utrecht,
The Netherlands
| | - Wei Ji
- Department
of Biomaterials, Radboud University Nijmegen Medical Center, P.O. Box
9101, 6500 HB, Nijmegen, The Netherlands
| | - Fang Yang
- Department
of Biomaterials, Radboud University Nijmegen Medical Center, P.O. Box
9101, 6500 HB, Nijmegen, The Netherlands
| | - Cornelus F. van Nostrum
- Department of Pharmaceutics,
Utrecht Institute for Pharmaceutical Sciences (UIPS), Faculty of Science, Utrecht University, P.O. Box 80082, 3508 TB Utrecht,
The Netherlands
| | - Tina Vermonden
- Department of Pharmaceutics,
Utrecht Institute for Pharmaceutical Sciences (UIPS), Faculty of Science, Utrecht University, P.O. Box 80082, 3508 TB Utrecht,
The Netherlands
| | - Jeroen J.J.P. van den Beucken
- Department
of Biomaterials, Radboud University Nijmegen Medical Center, P.O. Box
9101, 6500 HB, Nijmegen, The Netherlands
| | - Wouter J.A. Dhert
- Department of Orthopaedics, University Medical Center Utrecht, P.O. Box 85500,
3508 GA Utrecht, The Netherlands
- Faculty of Veterinary Medicine, Utrecht University, P.O. Box 80163, 3508 TD Utrecht,
The Netherlands
| | - Wim E. Hennink
- Department of Pharmaceutics,
Utrecht Institute for Pharmaceutical Sciences (UIPS), Faculty of Science, Utrecht University, P.O. Box 80082, 3508 TB Utrecht,
The Netherlands
| | - John A. Jansen
- Department
of Biomaterials, Radboud University Nijmegen Medical Center, P.O. Box
9101, 6500 HB, Nijmegen, The Netherlands
| |
Collapse
|
27
|
Highly potent VEGF-A-antagonistic DARPins as anti-angiogenic agents for topical and intravitreal applications. Angiogenesis 2012; 16:101-11. [PMID: 22983424 PMCID: PMC3526737 DOI: 10.1007/s10456-012-9302-0] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2011] [Accepted: 08/24/2012] [Indexed: 01/08/2023]
Abstract
The next-generation ophthalmic anti-VEGF therapeutics must aim at being superior to the currently available agents with regard to potency and improved drug delivery, while still being stable and safe to use at elevated concentrations. We show here the generation of a set of highly potent VEGF-A antagonistic DARPins (designed ankyrin repeat proteins) delivering these properties. DARPins with single-digit picomolar affinity to human VEGF-A were generated using ribosome display selections. Specific and potent human VEGF-A binding was confirmed by ELISA and endothelial cell sprouting assays. Cross-reactivity with VEGF-A of several species was confirmed by ELISA. Intravitreally injected DARPin penetrated into the retina and reduced fluorescein extravasation in a rabbit model of vascular leakage. In addition, topical DARPin application was found to diminish corneal neovascularization in a rabbit suture model, and to suppress laser-induced neovascularization in a rat model. Even at elevated doses, DARPins were safe to use. The fact that several DARPins are highly active in various assays illustrates the favorable class behavior of the selected binders. Anti-VEGF-A DARPins thus represent a novel class of highly potent and specific drug candidates for the treatment of neovascular eye diseases in both the posterior and the anterior eye chamber.
Collapse
|
28
|
Maiolo D, Mitola S, Leali D, Oliviero G, Ravelli C, Bugatti A, Depero LE, Presta M, Bergese P. Role of nanomechanics in canonical and noncanonical pro-angiogenic ligand/VEGF receptor-2 activation. J Am Chem Soc 2012; 134:14573-9. [PMID: 22860754 DOI: 10.1021/ja305816p] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Vascular endothelial growth factor receptor-2 (VEGFR2) is an endothelial cell receptor that plays a pivotal role in physiologic and pathologic angiogenesis and is a therapeutic target for angiogenesis-dependent diseases, including cancer. By leveraging on a dedicated nanomechanical biosensor, we investigated the nanoscale mechanical phenomena intertwined with VEGFR2 surface recognition by its prototypic ligand VEGF-A and its noncanonical ligand gremlin. We found that the two ligands bind the immobilized extracellular domain of VEGFR2 (sVEGFR2) with comparable binding affinity. Nevertheless, they interact with sVEGFR2 with different binding kinetics and drive different in-plane piconewton intermolecular forces, suggesting that the binding of VEGF-A or gremlin induces different conformational changes in sVEGFR2. These behaviors can be effectively described in terms of a different "nanomechanical affinity" of the two ligands for sVEGFR2, about 16-fold higher for VEGF-A with respect to gremlin. Such nanomechanical differences affect the biological activity driven by the two angiogenic factors in endothelial cells, as evidenced by a more rapid VEGFR2 clustering and a more potent mitogenic response triggered by VEGF-A in respect to gremlin. Together, these data point to surface intermolecular interactions on cell membrane between activated receptors as a key modulator of the intracellular signaling cascade.
Collapse
Affiliation(s)
- Daniele Maiolo
- Chemistry for Technologies Laboratory and INSTM, School of Engineering, University of Brescia, Via Branze, 38, 25123 Brescia, Italy
| | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Targeting extracellular domains D4 and D7 of vascular endothelial growth factor receptor 2 reveals allosteric receptor regulatory sites. Mol Cell Biol 2012; 32:3802-13. [PMID: 22801374 DOI: 10.1128/mcb.06787-11] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Vascular endothelial growth factors (VEGFs) activate three receptor tyrosine kinases, VEGFR-1, -2, and -3, which regulate angiogenic and lymphangiogenic signaling. VEGFR-2 is the most prominent receptor in angiogenic signaling by VEGF ligands. The extracellular part of VEGF receptors consists of seven immunoglobulin homology domains (Ig domains). Earlier studies showed that domains 2 and 3 (D23) mediate ligand binding, while structural analysis of dimeric ligand/receptor complexes by electron microscopy and small-angle solution scattering revealed additional homotypic contacts in membrane-proximal Ig domains D4 and D7. Here we show that D4 and D7 are indispensable for receptor signaling. To confirm the essential role of these domains in signaling, we isolated VEGFR-2-inhibitory "designed ankyrin repeat proteins" (DARPins) that interact with D23, D4, or D7. DARPins that interact with D23 inhibited ligand binding, receptor dimerization, and receptor kinase activation, while DARPins specific for D4 or D7 did not prevent ligand binding or receptor dimerization but effectively blocked receptor signaling and functional output. These data show that D4 and D7 allosterically regulate VEGFR-2 activity. We propose that these extracellular-domain-specific DARPins represent a novel generation of receptor-inhibitory drugs for in vivo applications such as targeting of VEGFRs in medical diagnostics and for treating vascular pathologies.
Collapse
|
30
|
Abstract
Abstract
VEGFs activate 3 receptor tyrosine kinases, VEGFR-1, VEGFR-2, and VEGFR-3, promoting angiogenic and lymphangiogenic signaling. The extracellular receptor domain (ECD) consists of 7 Ig-homology domains; domains 2 and 3 (D23) represent the ligand-binding domain, whereas the function of D4-7 is unclear. Ligand binding promotes receptor dimerization and instigates transmembrane signaling and receptor kinase activation. In the present study, isothermal titration calorimetry showed that the Gibbs free energy of VEGF-A, VEGF-C, or VEGF-E binding to D23 or the full-length ECD of VEGFR-2 is dominated by favorable entropic contribution with enthalpic penalty. The free energy of VEGF binding to the ECD is 1.0-1.7 kcal/mol less favorable than for binding to D23. A model of the VEGF-E/VEGFR-2 ECD complex derived from small-angle scattering data provided evidence for homotypic interactions in D4-7. We also solved the crystal structures of complexes between VEGF-A or VEGF-E with D23, which revealed comparable binding surfaces and similar interactions between the ligands and the receptor, but showed variation in D23 twist angles. The energetically unfavorable homotypic interactions in D4-7 may be required for re-orientation of receptor monomers, and this mechanism might prevent ligand-independent activation of VEGFR-2 to evade the deleterious consequences for blood and lymph vessel homeostasis arising from inappropriate receptor activation.
Collapse
|
31
|
Stengel F, Aebersold R, Robinson CV. Joining forces: integrating proteomics and cross-linking with the mass spectrometry of intact complexes. Mol Cell Proteomics 2011; 11:R111.014027. [PMID: 22180098 PMCID: PMC3316738 DOI: 10.1074/mcp.r111.014027] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Protein assemblies are critical for cellular function and understanding their physical organization is the key aim of structural biology. However, applying conventional structural biology approaches is challenging for transient, dynamic, or polydisperse assemblies. There is therefore a growing demand for hybrid technologies that are able to complement classical structural biology methods and thereby broaden our arsenal for the study of these important complexes. Exciting new developments in the field of mass spectrometry and proteomics have added a new dimension to the study of protein-protein interactions and protein complex architecture. In this review, we focus on how complementary mass spectrometry-based techniques can greatly facilitate structural understanding of protein assemblies.
Collapse
Affiliation(s)
- Florian Stengel
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Oxford, OX1 3TA United Kingdom
| | | | | |
Collapse
|
32
|
|