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Aghaei Z, Karbalaei N, Namavar MR, Haghani M, Razmkhah M, Ghaffari MK, Nemati M. Neuroprotective Effect of Wharton's Jelly-Derived Mesenchymal Stem Cell-Conditioned Medium (WJMSC-CM) on Diabetes-Associated Cognitive Impairment by Improving Oxidative Stress, Neuroinflammation, and Apoptosis. Stem Cells Int 2023; 2023:7852394. [PMID: 37081849 PMCID: PMC10113062 DOI: 10.1155/2023/7852394] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 03/13/2023] [Accepted: 03/16/2023] [Indexed: 04/22/2023] Open
Abstract
According to strong evidence, diabetes mellitus increases the risk of cognitive impairment. Mesenchymal stem cells have been shown to be potential therapeutic agents for neurological disorders. In the current study, we aimed to examine the effects of Wharton's jelly-derived mesenchymal stem cell-conditioned medium (WJMSC-CM) on learning and memory, oxidative stress, apoptosis, and histological changes in the hippocampus of diabetic rats. Randomly, 35 male Sprague Dawley rats weighing 260-300 g were allocated into five groups: control, diabetes, and three diabetic groups treated with insulin, WJMSC-CM, and DMEM. The injections of insulin (3 U/day, S.C.) and WJMSC-CM (10 mg/week, I.P.) were done for 60 days. The Morris water maze and open field were used to measure cognition and anxiety-like behaviors. Colorimetric assays were used to determine hippocampus glutathione (GSH), malondialdehyde (MDA) levels, and antioxidant enzyme activity. The histopathological evaluation of the hippocampus was performed by Nissl staining. The expression levels of Bax, Bcl-2, BDNF, and TNF-α were detected by real-time polymerase chain reaction (RT-PCR). According to our findings, WJMSC-CM significantly reduced and increased blood glucose and insulin levels, respectively. Enhanced cognition and improved anxiety-like behavior were also found in WJMSC-CM-treated diabetic rats. In addition, WJMSC-CM treatment reduced oxidative stress by lowering MDA and elevating GSH and antioxidant enzyme activity. Reduced TNF-α and enhanced Bcl-2 gene expression levels and elevated neuronal and nonneuronal (astrocytes and oligodendrocytes) cells were detected in the hippocampus of WJMSC-CM-treated diabetic rats. In conclusion, WJMSC-CM alleviated diabetes-related cognitive impairment by reducing oxidative stress, neuroinflammation, and apoptosis in diabetic rats.
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Affiliation(s)
- Zohre Aghaei
- Department of Physiology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Narges Karbalaei
- Department of Physiology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
- Histomorphometry and Stereology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mohammad Reza Namavar
- Histomorphometry and Stereology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
- Department of Anatomy, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Masoud Haghani
- Department of Physiology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
- Histomorphometry and Stereology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mahboobeh Razmkhah
- Department of Tissue Engineering and Applied Cell Sciences, School of Advanced Medical Sciences and Technologies, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mahdi Khorsand Ghaffari
- Department of Physiology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Marzieh Nemati
- Department of Endocrinology and Metabolism Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
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The Role of NEDD4 E3 Ubiquitin–Protein Ligases in Parkinson’s Disease. Genes (Basel) 2022; 13:genes13030513. [PMID: 35328067 PMCID: PMC8950476 DOI: 10.3390/genes13030513] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 03/03/2022] [Indexed: 01/25/2023] Open
Abstract
Parkinson’s disease (PD) is a debilitating neurodegenerative disease that causes a great clinical burden. However, its exact molecular pathologies are not fully understood. Whilst there are a number of avenues for research into slowing, halting, or reversing PD, one central idea is to enhance the clearance of the proposed aetiological protein, oligomeric α-synuclein. Oligomeric α-synuclein is the main constituent protein in Lewy bodies and neurites and is considered neurotoxic. Multiple E3 ubiquitin-protein ligases, including the NEDD4 (neural precursor cell expressed developmentally downregulated protein 4) family, parkin, SIAH (mammalian homologues of Drosophila seven in absentia), CHIP (carboxy-terminus of Hsc70 interacting protein), and SCFFXBL5 SCF ubiquitin ligase assembled by the S-phase kinase-associated protein (SKP1), cullin-1 (Cul1), a zinc-binding RING finger protein, and the F-box domain/Leucine-rich repeat protein 5-containing protein FBXL5), have been shown to be able to ubiquitinate α-synuclein, influencing its subsequent degradation via the proteasome or lysosome. Here, we explore the link between NEDD4 ligases and PD, which is not only via α-synuclein but further strengthened by several additional substrates and interaction partners. Some members of the NEDD4 family of ligases are thought to crosstalk even with PD-related genes and proteins found to be mutated in familial forms of PD. Mutations in NEDD4 family genes have not been observed in PD patients, most likely because of their essential survival function during development. Following further in vivo studies, it has been thought that NEDD4 ligases may be viable therapeutic targets in PD. NEDD4 family members could clear toxic proteins, enhancing cell survival and slowing disease progression, or might diminish beneficial proteins, reducing cell survival and accelerating disease progression. Here, we review studies to date on the expression and function of NEDD4 ubiquitin ligases in the brain and their possible impact on PD pathology.
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Bayat M, Khalili A, Bayat G, Akbari S, Yousefi Nejad A, Borhani Haghighi A, Haghani M. Effects of platelet-rich plasma on the memory impairment, apoptosis, and hippocampal synaptic plasticity in a rat model of hepatic encephalopathy. Brain Behav 2022; 12:e2447. [PMID: 34855284 PMCID: PMC8785608 DOI: 10.1002/brb3.2447] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 09/22/2021] [Accepted: 10/30/2021] [Indexed: 11/12/2022] Open
Abstract
OBJECTIVES In the present study, we aimed to determine whether intraperitoneal injection of platelet-rich plasma (PRP) could have a neuroprotective effect on learning, memory, and synaptic plasticity impairment as well as hippocampal apoptosis in rats with hepatic encephalopathy induced by bile duct ligated (BDL). METHODS The rats were divided into four groups: the control, sham, BDL+ V (vehicle), and BDL+ PRP. The BDL rats were treated with PRP immediately after the surgery, and the injection was done every 3 days for 30 days. The passive avoidance and Morris water maze tests were used for the evaluation of learning and memory. The long-term potentiation (LTP), basal-synaptic transmission, and paired-pulse ratio, as an index for measurement of neurotransmitter release probability, were evaluated by field-potential recording. After taking a blood sample for assessment of the liver enzymes, the animals were sacrificed and their hippocampus was removed for evaluation of cleaved caspase-3 by Western blot. RESULTS Serological assessment of the liver function showed that BDL severely impaired the liver function. Also, PRP treatment could partially improve the liver dysfunction along with recovery in fear memory and spatial learning memory performance, LTP, basal-synaptic transmission, and neurotransmitter release probability. PRP-treated rats also showed a significant reduction in neuronal apoptosis in the CA1 area. CONCLUSIONS The results of this study suggest that PRP improves cognitive performance and synaptic plasticity in BDL rats via direct neuroprotective property and/or indirectly by improvement of hepatic dysfunction.
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Affiliation(s)
- Mahnaz Bayat
- Clinical Neurology Research Centre, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Azadeh Khalili
- Department of Physiology-Pharmacology-Medical Physic, School of Medicine, Alborz University of Medical Sciences, Karaj, Iran
| | - Gholamreza Bayat
- Department of Physiology-Pharmacology-Medical Physic, School of Medicine, Alborz University of Medical Sciences, Karaj, Iran.,Cardiovascular Research Center, Alborz University of Medical Sciences, Karaj, Iran
| | - Somayeh Akbari
- Department of Physiology, The Medical School, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Amirhossein Yousefi Nejad
- Faculty of Veterinary Medicine, Department of Veterinary Medicine, Islamic Azad University of Kazeroon, Shiraz, Iran
| | | | - Masoud Haghani
- Department of Physiology, The Medical School, Shiraz University of Medical Sciences, Shiraz, Iran.,Histomorphometry and Stereology Research Centre, Shiraz University of Medical Sciences, Shiraz, Iran
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A widespread viral entry mechanism: The C-end Rule motif-neuropilin receptor interaction. Proc Natl Acad Sci U S A 2021; 118:2112457118. [PMID: 34772761 PMCID: PMC8670474 DOI: 10.1073/pnas.2112457118] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/22/2021] [Indexed: 01/31/2023] Open
Abstract
Many phylogenetically distant animal viruses, including the new coronavirus severe acute respiratory syndrome coronavirus 2, have surface proteins with polybasic sites that are cleaved by host furin and furin-like proteases. Other than priming certain viral surface proteins for fusion, cleavage generates a carboxy-terminal RXXR sequence. This C-end Rule (CendR) motif is known to bind to neuropilin (NRP) receptors on the cell surface. NRPs are ubiquitously expressed, pleiotropic cell surface receptors with important roles in growth factor signaling, vascular biology, and neurobiology, as well as immune homeostasis and activation. The CendR–NRP receptor interaction promotes endocytic internalization and tissue spreading of different cargo, including viral particles. We propose that the interaction between viral surface proteins and NRPs plays an underappreciated and prevalent role in the transmission and pathogenesis of diverse viruses and represents a promising broad-spectrum antiviral target.
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Costa D, Ferreira R, Prada J, Queiroga FL, Rodrigues P, Silva F, Pires I. A Role for Angiogenesis in Canine Cutaneous Histiocytoma Regression: Insights into an Old Clinical Enigma. In Vivo 2021; 34:3279-3284. [PMID: 33144434 DOI: 10.21873/invivo.12165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 09/06/2020] [Accepted: 09/16/2020] [Indexed: 11/10/2022]
Abstract
BACKGROUND/AIM Canine Cutaneous Histiocytoma (CCH) is a Langerhans' cells benign tumour that undergoes spontaneous regression. The aim of the present study was to investigate the role of angiogenesis, a key step for tumour development, in CCH regression. MATERIALS AND METHODS 50 CCH samples were classified into 4 histological groups according to a regression scale, and evaluated for expression of vascular endothelial factor-A (VEGF-A) and its receptor VEGFR-2 as well as microvessel density (MVD). RESULTS Tumours during early stages of the regressive process had a lower MVD compared to later stages, while CCH tumoural cells showed a limited production of VEGF, but higher levels of VEGFR-2. On the contrary, tumours in advanced phases of regression showed a higher number of neovessels, probably associated with the inflammatory state and the healing process. CONCLUSION Our results suggest that angiogenesis may be compromised at early stages of histiocytoma development and this may be a determinant of regression in this tumour.
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Affiliation(s)
- Diana Costa
- Department of Genetics and Biotechnology, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal
| | - Rita Ferreira
- Department of Genetics and Biotechnology, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal
| | - Justina Prada
- Department of Veterinary Sciences, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal.,Animal and Veterinary Research Centre (CECAV), University of Trás-os-Montes and Alto Douro, Vila Real, Portugal
| | - Felisbina Luisa Queiroga
- Department of Veterinary Sciences, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal .,Center for Research and Technology of Agro-Environment and Biological Sciences (CITAB), University of Trás-os-Montes and Alto Douro, Vila Real, Portugal.,Center for the Study of Animal Sciences, CECA-ICETA, University of Porto, Porto, Portugal
| | - Paula Rodrigues
- Department of Veterinary Sciences, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal.,Animal and Veterinary Research Centre (CECAV), University of Trás-os-Montes and Alto Douro, Vila Real, Portugal
| | - Filipe Silva
- Department of Veterinary Sciences, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal.,Animal and Veterinary Research Centre (CECAV), University of Trás-os-Montes and Alto Douro, Vila Real, Portugal
| | - Isabel Pires
- Department of Veterinary Sciences, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal.,Animal and Veterinary Research Centre (CECAV), University of Trás-os-Montes and Alto Douro, Vila Real, Portugal
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Wang C, Ding S, Wang S, Shi Z, Pandey NK, Chudal L, Wang L, Zhang Z, Wen Y, Yao H, Lin L, Chen W, Xiong L. Endogenous tumor microenvironment-responsive multifunctional nanoplatforms for precision cancer theranostics. Coord Chem Rev 2021. [DOI: 10.1016/j.ccr.2020.213529] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Bhattacharjee S, Lee Y, Zhu B, Wu H, Chen Y, Chen H. Epsins in vascular development, function and disease. Cell Mol Life Sci 2020; 78:833-842. [PMID: 32930806 DOI: 10.1007/s00018-020-03642-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 08/14/2020] [Accepted: 09/03/2020] [Indexed: 12/15/2022]
Abstract
Epsins are a family of adaptor proteins involved in clathrin-dependent endocytosis. In the vasculature, epsins 1 and 2 are functionally redundant members of this family that are expressed in the endothelial cells of blood vessels and the lymphatic system throughout development and adulthood. These proteins contain a number of peptide motifs that allow them to interact with lipid moieties and a variety of proteins. These interactions facilitate the regulation of a wide range of cell signaling pathways. In this review, we focus on the involvement of epsins 1 and 2 in controlling vascular endothelial growth factor receptor signaling in angiogenesis and lymphangiogenesis. We also discuss the therapeutic implications of understanding the molecular mechanisms of epsin-mediated regulation in diseases such as atherosclerosis and diabetes.
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Affiliation(s)
- Sudarshan Bhattacharjee
- Vascular Biology Program, Harvard Medical School, Boston Children's Hospital and Department of Surgery, Boston, MA, 02115, USA
| | - Yang Lee
- Vascular Biology Program, Harvard Medical School, Boston Children's Hospital and Department of Surgery, Boston, MA, 02115, USA
| | - Bo Zhu
- Vascular Biology Program, Harvard Medical School, Boston Children's Hospital and Department of Surgery, Boston, MA, 02115, USA
| | - Hao Wu
- Vascular Biology Program, Harvard Medical School, Boston Children's Hospital and Department of Surgery, Boston, MA, 02115, USA
| | - Yabing Chen
- Department of Pathology, Birmingham Veterans Affairs Medical Center, University of Alabama at Birmingham and Research Department, Birmingham, AL, 35294, USA
| | - Hong Chen
- Vascular Biology Program, Harvard Medical School, Boston Children's Hospital and Department of Surgery, Boston, MA, 02115, USA.
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8
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Regulation of VEGFR2 trafficking and signaling by Rab GTPase-activating proteins. Sci Rep 2019; 9:13342. [PMID: 31527750 PMCID: PMC6746989 DOI: 10.1038/s41598-019-49646-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Accepted: 08/29/2019] [Indexed: 12/19/2022] Open
Abstract
Vascular endothelial growth factor receptor-2 (VEGFR2) and its ligands (VEGFs) are crucial players in vasculogenesis and angiogenesis. General blocking of this signaling system with antibodies or small molecule inhibitors is an established strategy to treat cancer and age-related macular degeneration. Nevertheless, the activated receptor can signal to discrete downstream signaling pathways and the equilibrium between these pathways is modulated by coreceptors and distinct isoforms of VEGF. Here we investigated the influence of Rab GTPase activating proteins (RabGAPs) on VEGFR2 signaling, tube formation, and migration of endothelial cells. We demonstrate that members of the TBC1D10 subfamily of RabGAPs have opposite effects. Whereas TBC1D10A leads to increased Erk1/2 signaling, TBC1D10B lowered Erk1/2 and p38 signaling and reduced tube formation in vitro. TBC1D10A is a RabGAP acting on RAB13 that was shown before to play a role in angiogenesis and we could indeed show colocalization of these two proteins with VEGFR2 in activated cells. In addition, we observed that cells expressing TBC1D10B show lower expression of VEGFR2 and NRP1 on filopodia of activated cells. Taken together, our systematic analysis of influence of RabGAPs on VEGFR2 signaling identifies the TBC1D10 subfamily members as modulators of angiogenesis.
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Zhao K, Li X, Lin B, Yang D, Zhou Y, Li Z, Guo Q, Lu N. Oroxyloside inhibits angiogenesis through suppressing internalization of VEGFR2/Flk-1 in endothelial cells. J Cell Physiol 2017; 233:3454-3464. [PMID: 28926106 DOI: 10.1002/jcp.26198] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 09/14/2017] [Indexed: 12/12/2022]
Abstract
Increasing flavonoids have been reported to possess anti-angiogenic effects. Inhibition of angiogenesis plays a critical role in the treatment of cancer, especially in advanced metastatic cancer. In this study, we assessed the effect of Oroxylin A-7-glucuronide (Oroxyloside), a main metabolite of Oroxylin A, on angiogenesis in human endothelial cell-like EA.hy926 cells. Oroxyloside suppressed the migration and tube formation of EA.hy926 cells. Meanwhile, microvessels sprouting from aortic rings and new blood vessels on the chicken chorioallantoic membrane (CAM) were also inhibited. Mechanism studies showed that Oroxyloside reduced the autophosphorylation of vascular endothelial growth factor receptor 2 (VEGFR2/Flk-1) while it up-regulated the expression of R-Ras and VE-cadherin. In consequence, Oroxyloside inhibited the downstream Akt/MAPK/NF-κB pathways and then decreased the nuclear translocation and DNA binding ability of NF-κB. Furthermore, in vivo study showed that Oroxyloside exhibited a potential anti-angiogenic effect in Matrigel plug assay and inhibited growth of xenografted tumors with low systemic toxicity, which could be ascribed to the inhibition of VEGFR2 internalization. Taken together, these results suggested that Oroxyloside could inhibit angiogenesis in vitro and in vivo via suppressing the internalization of VEGFR2 and might serve as a potential antitumor agent.
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Affiliation(s)
- Kai Zhao
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Carcinogenesis and Intervention, Department of Basic Medicine, School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, P.R. China
| | - Xiaorui Li
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Carcinogenesis and Intervention, Department of Basic Medicine, School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, P.R. China
| | - Binyan Lin
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Carcinogenesis and Intervention, Department of Basic Medicine, School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, P.R. China
| | - Dawei Yang
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Carcinogenesis and Intervention, Department of Basic Medicine, School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, P.R. China
| | - Yuxin Zhou
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Carcinogenesis and Intervention, Department of Basic Medicine, School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, P.R. China
| | - Zhiyu Li
- Department of Medicinal Chemistry, China Pharmaceutical University, Nanjing, P.R. China
| | - Qinglong Guo
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Carcinogenesis and Intervention, Department of Basic Medicine, School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, P.R. China
| | - Na Lu
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Carcinogenesis and Intervention, Department of Basic Medicine, School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, P.R. China
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11
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Hendricks C, Dubail J, Brohée L, Delforge Y, Colige A, Deroanne C. A Novel Physiological Glycosaminoglycan-Deficient Splice Variant of Neuropilin-1 Is Anti-Tumorigenic In Vitro and In Vivo. PLoS One 2016; 11:e0165153. [PMID: 27798666 PMCID: PMC5087894 DOI: 10.1371/journal.pone.0165153] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 10/09/2016] [Indexed: 01/13/2023] Open
Abstract
Neuropilin-1 (NRP1) is a transmembrane protein acting as a co-receptor for several growth factors and interacting with other proteins such as integrins and plexins/semaphorins. It is involved in axonal development, angiogenesis and cancer progression. Its primary mRNA is subjected to alternative splicing mechanisms generating different isoforms, some of which lack the transmembrane domain and display antagonist properties to NRP1 full size (FS). NRP1 is further post-translationally modified by the addition of glycosaminoglycans (GAG) side chains through an O-glycosylation site at serine612. Here, we characterized a novel splice variant which has never been investigated, NRP1-Δ7, differing from the NRP1-FS by a deletion of 7 amino acids occurring two residues downstream of the O-glycosylation site. This short sequence contains two aspartic residues critical for efficient glycosylation. As expected, the high molecular weight products appearing as a smear in SDS-PAGE and reflecting the presence of GAG in NRP1-FS were undetectable in the NRP1-Δ7 protein. NRP1-Δ7 mRNA was found expressed at an appreciable level, between 10 and 30% of the total NRP1, by various cells lines and tissues from human and murine origin. To investigate the biological properties of this isoform, we generated prostatic (PC3) and breast (MDA-MB-231) cancer cells able to express recombinant NRP1-FS or NRP1-Δ7 in a doxycycline-inducible manner. Cells with increased expression of NRP1-Δ7 were characterized in vitro by a significant reduction of proliferation, migration and anchorage-independent growth, while NRP1-FS had the expected opposite “pro-tumoral” effects. Upon VEGF-A165 treatment, a lower internalization rate was observed for NRP1-Δ7 than for NRP1-FS. Finally, we showed that NRP1-Δ7 inhibited growth of prostatic tumors and their vascularization in vivo. This report identifies NRP1-Δ7 as a splice variant displaying anti-tumorigenic properties in vitro and in vivo, emphasizing the need to consider this isoform in future studies.
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Affiliation(s)
- Céline Hendricks
- Laboratory of Connective Tissues Biology, Tour de Pathologie, GIGA-Cancer, University of Liège, Sart-Tilman, Belgium
| | - Johanne Dubail
- Laboratory of Connective Tissues Biology, Tour de Pathologie, GIGA-Cancer, University of Liège, Sart-Tilman, Belgium
| | - Laura Brohée
- Laboratory of Connective Tissues Biology, Tour de Pathologie, GIGA-Cancer, University of Liège, Sart-Tilman, Belgium
| | - Yves Delforge
- Laboratory of Connective Tissues Biology, Tour de Pathologie, GIGA-Cancer, University of Liège, Sart-Tilman, Belgium
| | - Alain Colige
- Laboratory of Connective Tissues Biology, Tour de Pathologie, GIGA-Cancer, University of Liège, Sart-Tilman, Belgium
- * E-mail: (AC)
| | - Christophe Deroanne
- Laboratory of Connective Tissues Biology, Tour de Pathologie, GIGA-Cancer, University of Liège, Sart-Tilman, Belgium
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Suzuki Y, Nagai N, Umemura K. A Review of the Mechanisms of Blood-Brain Barrier Permeability by Tissue-Type Plasminogen Activator Treatment for Cerebral Ischemia. Front Cell Neurosci 2016; 10:2. [PMID: 26834557 PMCID: PMC4724711 DOI: 10.3389/fncel.2016.00002] [Citation(s) in RCA: 89] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 01/04/2016] [Indexed: 11/13/2022] Open
Abstract
Cerebrovascular homeostasis is maintained by the blood-brain barrier (BBB), which forms a mechanical and functional barrier between systemic circulation and the central nervous system (CNS). In patients with ischemic stroke, the recombinant tissue-type plasminogen activator (rt-PA) is used to accelerate recanalization of the occluded vessels. However, rt-PA is associated with a risk of increasing intracranial bleeding (ICB). This effect is thought to be caused by the increase in cerebrovascular permeability though various factors such as ischemic reperfusion injury and the activation of matrix metalloproteinases (MMPs), but the detailed mechanisms are unknown. It was recently found that rt-PA treatment enhances BBB permeability not by disrupting the BBB, but by activating the vascular endothelial growth factor (VEGF) system. The VEGF regulates both the dissociation of endothelial cell (EC) junctions and endothelial endocytosis, and causes a subsequent increase in vessel permeability through the VEGF receptor-2 (VEGFR-2) activation in ECs. Here, we review the possibility that rt-PA increases the penetration of toxic molecules derived from the bloodstream including rt-PA itself, without disrupting the BBB, and contributes to these detrimental processes in the cerebral parenchyma.
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Affiliation(s)
- Yasuhiro Suzuki
- Department of Pharmacology, Hamamatsu University School of MedicineHamamatsu, Japan; School of Pharmaceutical Sciences, Ohu UniversityKoriyama, Japan
| | - Nobuo Nagai
- Faculty of Bioscience, Department of Animal Bioscience, Nagahama Institute of Bio-Science and Technology Nagahama, Japan
| | - Kazuo Umemura
- Department of Pharmacology, Hamamatsu University School of Medicine Hamamatsu, Japan
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Takyar S, Zhang Y, Haslip M, Jin L, Shan P, Zhang X, Lee PJ. An endothelial TLR4-VEGFR2 pathway mediates lung protection against oxidant-induced injury. FASEB J 2015; 30:1317-27. [PMID: 26655705 DOI: 10.1096/fj.15-275024] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 11/23/2015] [Indexed: 02/05/2023]
Abstract
TLR4 deficiency causes hypersusceptibility to oxidant-induced injury. We investigated the role of TLR4 in lung protection, using used bone marrow chimeras; cell-specific transgenic modeling; and lentiviral delivery in vivo to knock down or express TLR4 in various lung compartments; and lung-specific VEGF transgenic mice to investigate the effect of TLR4 on VEGF-mediated protection. C57/BL6 mice were exposed to 100% oxygen in an enclosed chamber and assessed for survival and lung injury. Primary endothelial cells were stimulated with recombinant VEGF and exposed to hyperoxia or hydrogen peroxide. Endothelium-specific expression of human TLR4 (as opposed to its expression in epithelium or immune cells) increased the survival of TLR4-deficent mice in hyperoxia by 24 h and decreased LDH release and lung cell apoptosis after 72 h of exposure by 30%. TLR4 expression was necessary and sufficient for the protective effect of VEGF in the lungs and in primary endothelial cells in culture. TLR4 knockdown inhibited VEGF signaling through VEGF receptor 2 (VEGFR2), Akt, and ERK pathways in lungs and primary endothelial cells and decreased the availability of VEGFR2 at the cell surface. These findings demonstrate a novel mechanism through which TLR4, an innate pattern receptor, interacts with an endothelial survival pathway.
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Affiliation(s)
- Seyedtaghi Takyar
- *Section of Pulmonary, Critical Care, and Sleep Medicine, and Department of Pathology, Yale University School of Medicine, New Haven, Connecticut, USA; and Veterans Affairs Connecticut Healthcare System, New Haven, Connecticut, USA
| | - Yi Zhang
- *Section of Pulmonary, Critical Care, and Sleep Medicine, and Department of Pathology, Yale University School of Medicine, New Haven, Connecticut, USA; and Veterans Affairs Connecticut Healthcare System, New Haven, Connecticut, USA
| | - Maria Haslip
- *Section of Pulmonary, Critical Care, and Sleep Medicine, and Department of Pathology, Yale University School of Medicine, New Haven, Connecticut, USA; and Veterans Affairs Connecticut Healthcare System, New Haven, Connecticut, USA
| | - Lei Jin
- *Section of Pulmonary, Critical Care, and Sleep Medicine, and Department of Pathology, Yale University School of Medicine, New Haven, Connecticut, USA; and Veterans Affairs Connecticut Healthcare System, New Haven, Connecticut, USA
| | - Peiying Shan
- *Section of Pulmonary, Critical Care, and Sleep Medicine, and Department of Pathology, Yale University School of Medicine, New Haven, Connecticut, USA; and Veterans Affairs Connecticut Healthcare System, New Haven, Connecticut, USA
| | - Xuchen Zhang
- *Section of Pulmonary, Critical Care, and Sleep Medicine, and Department of Pathology, Yale University School of Medicine, New Haven, Connecticut, USA; and Veterans Affairs Connecticut Healthcare System, New Haven, Connecticut, USA
| | - Patty J Lee
- *Section of Pulmonary, Critical Care, and Sleep Medicine, and Department of Pathology, Yale University School of Medicine, New Haven, Connecticut, USA; and Veterans Affairs Connecticut Healthcare System, New Haven, Connecticut, USA
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14
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Baburajeev CP, Dhananjaya Mohan C, Ananda H, Rangappa S, Fuchs JE, Jagadish S, Sivaraman Siveen K, Chinnathambi A, Ali Alharbi S, Zayed ME, Zhang J, Li F, Sethi G, Girish KS, Bender A, Basappa, Rangappa KS. Development of Novel Triazolo-Thiadiazoles from Heterogeneous "Green" Catalysis as Protein Tyrosine Phosphatase 1B Inhibitors. Sci Rep 2015; 5:14195. [PMID: 26388336 PMCID: PMC4585680 DOI: 10.1038/srep14195] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 08/18/2015] [Indexed: 02/06/2023] Open
Abstract
Condensed-bicyclic triazolo-thiadiazoles were synthesized via an efficient "green" catalyst strategy and identified as effective inhibitors of PTP1B in vitro. The lead compound, 6-(2-benzylphenyl)-3-phenyl-[1,2,4]triazolo[3][1,3,4]thiadiazole (BPTT) was most effective against human hepatoma cells, inhibits cell invasion, and decreases neovasculature in HUVEC and also tumor volume in EAT mouse models. This report describes an experimentally unidentified class of condensed-bicyclic triazolo-thiadiazoles targeting PTP1B and its analogs could be the therapeutic drug-seeds.
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Affiliation(s)
- C P Baburajeev
- Laboratory of Chemical Biology, Department of Chemistry, Bangalore University, Palace Road, Bangalore 560001, India
| | | | - Hanumappa Ananda
- Department of Studies in Chemistry, University of Mysore, Manasagangotri, Mysore-570006, India
| | - Shobith Rangappa
- Frontier Research Center for Post-genome Science and Technology, Hokkaido University, Sapporo 0600808, Japan
| | - Julian E Fuchs
- Centre for Molecular Informatics, Department of Chemistry, University of Cambridge, Lensfield Road, CB2 1EW, Cambridge, United Kingdom
| | - Swamy Jagadish
- Department of Studies in Chemistry, University of Mysore, Manasagangotri, Mysore-570006, India
| | - Kodappully Sivaraman Siveen
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore-117597, Singapore
| | - Arunachalam Chinnathambi
- Department of Botany and Microbiology, College of Science, King Saudi University, Riyadh -11451, Kingdom of Saudi Arabia
| | - Sulaiman Ali Alharbi
- Department of Botany and Microbiology, College of Science, King Saudi University, Riyadh -11451, Kingdom of Saudi Arabia
| | - M E Zayed
- Department of Botany and Microbiology, College of Science, King Saudi University, Riyadh -11451, Kingdom of Saudi Arabia
| | - Jingwen Zhang
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore-117597, Singapore
| | - Feng Li
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore-117597, Singapore
| | - Gautam Sethi
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore-117597, Singapore
| | - Kesturu S Girish
- Department of Studies in Biochemistry, University of Mysore, Manasagangotri, Mysore-570006, India
| | - Andreas Bender
- Centre for Molecular Informatics, Department of Chemistry, University of Cambridge, Lensfield Road, CB2 1EW, Cambridge, United Kingdom
| | - Basappa
- Laboratory of Chemical Biology, Department of Chemistry, Bangalore University, Palace Road, Bangalore 560001, India
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15
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Harney AS, Arwert EN, Entenberg D, Wang Y, Guo P, Qian BZ, Oktay MH, Pollard JW, Jones JG, Condeelis JS. Real-Time Imaging Reveals Local, Transient Vascular Permeability, and Tumor Cell Intravasation Stimulated by TIE2hi Macrophage-Derived VEGFA. Cancer Discov 2015; 5:932-43. [PMID: 26269515 PMCID: PMC4560669 DOI: 10.1158/2159-8290.cd-15-0012] [Citation(s) in RCA: 410] [Impact Index Per Article: 45.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Accepted: 06/09/2015] [Indexed: 12/11/2022]
Abstract
UNLABELLED Dissemination of tumor cells is an essential step in metastasis. Direct contact between a macrophage, mammalian-enabled (MENA)-overexpressing tumor cell, and endothelial cell [Tumor MicroEnvironment of Metastasis (TMEM)] correlates with metastasis in breast cancer patients. Here we show, using intravital high-resolution two-photon microscopy, that transient vascular permeability and tumor cell intravasation occur simultaneously and exclusively at TMEM. The hyperpermeable nature of tumor vasculature is described as spatially and temporally heterogeneous. Using real-time imaging, we observed that vascular permeability is transient, restricted to the TMEM, and required for tumor cell dissemination. VEGFA signaling from TIE2(hi) TMEM macrophages causes local loss of vascular junctions, transient vascular permeability, and tumor cell intravasation, demonstrating a role for the TMEM within the primary mammary tumor. These data provide insight into the mechanism of tumor cell intravasation and vascular permeability in breast cancer, explaining the value of TMEM density as a predictor of distant metastatic recurrence in patients. SIGNIFICANCE Tumor vasculature is abnormal with increased permeability. Here, we show that VEGFA signaling from TIE2(hi) TMEM macrophages results in local, transient vascular permeability and tumor cell intravasation. These data provide evidence for the mechanism underlying the association of TMEM with distant metastatic recurrence, offering a rationale for therapies targeting TMEM.
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Affiliation(s)
- Allison S Harney
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, New York, New York. Department of Radiology, Albert Einstein College of Medicine, New York, New York. Integrated Imaging Program, Albert Einstein College of Medicine, New York, New York. Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, New York, New York.
| | - Esther N Arwert
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, New York, New York. Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, New York, New York. Tumour Cell Biology Laboratory, Cancer Research UK, London Research Institute, London, United Kingdom
| | - David Entenberg
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, New York, New York. Integrated Imaging Program, Albert Einstein College of Medicine, New York, New York. Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, New York, New York
| | - Yarong Wang
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, New York, New York. Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, New York, New York
| | - Peng Guo
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, New York, New York. Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, New York, New York
| | - Bin-Zhi Qian
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, New York, New York. Department of Obstetrics & Gynecology and Women's Health, Albert Einstein College of Medicine, New York, New York. MRC Center for Reproductive Health, University of Edinburgh, Edinburgh, United Kingdom
| | - Maja H Oktay
- Department of Pathology, Albert Einstein College of Medicine, New York, New York
| | - Jeffrey W Pollard
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, New York, New York. Department of Obstetrics & Gynecology and Women's Health, Albert Einstein College of Medicine, New York, New York. MRC Center for Reproductive Health, University of Edinburgh, Edinburgh, United Kingdom
| | - Joan G Jones
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, New York, New York. Integrated Imaging Program, Albert Einstein College of Medicine, New York, New York. Department of Pathology, Albert Einstein College of Medicine, New York, New York. Department of Epidemiology and Population Health, Albert Einstein College of Medicine, New York, New York
| | - John S Condeelis
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, New York, New York. Integrated Imaging Program, Albert Einstein College of Medicine, New York, New York. Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, New York, New York.
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16
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Pitulescu ME, Adams RH. Regulation of signaling interactions and receptor endocytosis in growing blood vessels. Cell Adh Migr 2015; 8:366-77. [PMID: 25482636 DOI: 10.4161/19336918.2014.970010] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Blood vessels and the lymphatic vasculature are extensive tubular networks formed by endothelial cells that have several indispensable functions in the developing and adult organism. During growth and tissue regeneration but also in many pathological settings, these vascular networks expand, which is critically controlled by the receptor EphB4 and the ligand ephrin-B2. An increasing body of evidence links Eph/ephrin molecules to the function of other receptor tyrosine kinases and cell surface receptors. In the endothelium, ephrin-B2 is required for clathrin-dependent internalization and full signaling activity of VEGFR2, the main receptor for vascular endothelial growth factor. In vascular smooth muscle cells, ephrin-B2 antagonizes clathrin-dependent endocytosis of PDGFRβ and controls the balanced activation of different signal transduction processes after stimulation with platelet-derived growth factor. This review summarizes the important roles of Eph/ephrin molecules in vascular morphogenesis and explains the function of ephrin-B2 as a molecular hub for receptor endocytosis in the vasculature.
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Key Words
- Ang, angiopoietin
- CHC, clathrin heavy chains
- CLASP, clathrin-associated-sorting protein
- CV, cardinal vein
- DA, dorsal aorta
- EC, endothelial cell
- EEA1, early antigen 1
- Eph
- Ephrin-B2ΔV, ephrin-B2 deletion of C-terminal PDZ binding motif
- HSPG, heparan sulfate proteoglycan
- JNK, c-Jun N-terminal kinase
- LEC, lymphatic endothelial cells
- LRP1, Low density lipoprotein receptor-related protein 1
- MVB, multivesicular body
- NRP, neuropilin
- PC, pericytes
- PDGF, platelet-derived growth factor
- PDGFR, platelet-derived growth factor receptor
- PTC, peritubular capillary
- PlGF, placental growth factor
- RTK, receptor tyrosine kinase
- VEGF, Vascular endothelial growth factor
- VEGFR, Vascular endothelial growth factor receptor
- VSMC, vascular smooth muscle cells.
- aPKC, atypical protein kinase C
- endocytosis
- endothelial cells
- ephrin
- mural cells
- receptor
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Affiliation(s)
- Mara E Pitulescu
- a Department of Tissue Morphogenesis; Max Planck Institute for Molecular Biomedicine; and Faculty of Medicine , University of Münster ; Münster , Germany
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17
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van Lessen M, Nakayama M, Kato K, Kim JM, Kaibuchi K, Adams RH. Regulation of vascular endothelial growth factor receptor function in angiogenesis by numb and numb-like. Arterioscler Thromb Vasc Biol 2015; 35:1815-25. [PMID: 26069237 DOI: 10.1161/atvbaha.115.305473] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Accepted: 05/31/2015] [Indexed: 02/06/2023]
Abstract
OBJECTIVE Vascular endothelial growth factor (VEGF) signaling is a major regulator of physiological and pathological angiogenesis. VEGF receptor activity is strongly controlled by endocytosis, which can terminate or enhance signal transduction in the angiogenic endothelium, but the exact molecular regulation of these processes remains incompletely understood. We have therefore examined the function of Numb family clathrin-associated sorting proteins in angiogenesis. APPROACH AND RESULTS We show that Numb proteins are expressed by endothelial cells during retinal angiogenesis in mice. Inducible inactivation of the Numb/Numbl genes in the postnatal endothelium led to impaired vessel growth, reduced endothelial proliferation and sprouting, and decreased VEGF receptor activation. Biochemistry and cell biology experiments established that Numb can interact with VEGFR2 and VEGFR3 and controls VEGF receptor activation in response to ligand stimulation. Experiments in cultured endothelial cells showed that Numb proteins counteract VEGF receptor degradation and promote VEGFR2 recycling back to the plasma membrane. CONCLUSIONS Numb proteins control VEGF receptor endocytosis, signaling, and recycling in endothelial cells, which promotes the angiogenic growth of blood vessels.
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Affiliation(s)
- Max van Lessen
- From the Max-Planck-Institute for Molecular Biomedicine, Department of Tissue Morphogenesis, and University of Münster, Faculty of Medicine, Münster, Germany (M.v.L., M.N., K. Kato, J.M.K., R.H.A.); and Department of Cell Pharmacology, Nagoya University, Graduate School of Medicine, Nagoya, Japan (K. Kato, K. Kaibuchi)
| | - Masanori Nakayama
- From the Max-Planck-Institute for Molecular Biomedicine, Department of Tissue Morphogenesis, and University of Münster, Faculty of Medicine, Münster, Germany (M.v.L., M.N., K. Kato, J.M.K., R.H.A.); and Department of Cell Pharmacology, Nagoya University, Graduate School of Medicine, Nagoya, Japan (K. Kato, K. Kaibuchi)
| | - Katsuhiro Kato
- From the Max-Planck-Institute for Molecular Biomedicine, Department of Tissue Morphogenesis, and University of Münster, Faculty of Medicine, Münster, Germany (M.v.L., M.N., K. Kato, J.M.K., R.H.A.); and Department of Cell Pharmacology, Nagoya University, Graduate School of Medicine, Nagoya, Japan (K. Kato, K. Kaibuchi)
| | - Jung Mo Kim
- From the Max-Planck-Institute for Molecular Biomedicine, Department of Tissue Morphogenesis, and University of Münster, Faculty of Medicine, Münster, Germany (M.v.L., M.N., K. Kato, J.M.K., R.H.A.); and Department of Cell Pharmacology, Nagoya University, Graduate School of Medicine, Nagoya, Japan (K. Kato, K. Kaibuchi)
| | - Kozo Kaibuchi
- From the Max-Planck-Institute for Molecular Biomedicine, Department of Tissue Morphogenesis, and University of Münster, Faculty of Medicine, Münster, Germany (M.v.L., M.N., K. Kato, J.M.K., R.H.A.); and Department of Cell Pharmacology, Nagoya University, Graduate School of Medicine, Nagoya, Japan (K. Kato, K. Kaibuchi)
| | - Ralf H Adams
- From the Max-Planck-Institute for Molecular Biomedicine, Department of Tissue Morphogenesis, and University of Münster, Faculty of Medicine, Münster, Germany (M.v.L., M.N., K. Kato, J.M.K., R.H.A.); and Department of Cell Pharmacology, Nagoya University, Graduate School of Medicine, Nagoya, Japan (K. Kato, K. Kaibuchi).
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18
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Clegg LW, Mac Gabhann F. Site-Specific Phosphorylation of VEGFR2 Is Mediated by Receptor Trafficking: Insights from a Computational Model. PLoS Comput Biol 2015; 11:e1004158. [PMID: 26067165 PMCID: PMC4466579 DOI: 10.1371/journal.pcbi.1004158] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Accepted: 01/25/2015] [Indexed: 02/05/2023] Open
Abstract
Matrix-binding isoforms and non-matrix-binding isoforms of vascular endothelial growth factor (VEGF) are both capable of stimulating vascular remodeling, but the resulting blood vessel networks are structurally and functionally different. Here, we develop and validate a computational model of the binding of soluble and immobilized ligands to VEGF receptor 2 (VEGFR2), the endosomal trafficking of VEGFR2, and site-specific VEGFR2 tyrosine phosphorylation to study differences in induced signaling between these VEGF isoforms. In capturing essential features of VEGFR2 signaling and trafficking, our model suggests that VEGFR2 trafficking parameters are largely consistent across multiple endothelial cell lines. Simulations demonstrate distinct localization of VEGFR2 phosphorylated on Y1175 and Y1214. This is the first model to clearly show that differences in site-specific VEGFR2 activation when stimulated with immobilized VEGF compared to soluble VEGF can be accounted for by altered trafficking of VEGFR2 without an intrinsic difference in receptor activation. The model predicts that Neuropilin-1 can induce differences in the surface-to-internal distribution of VEGFR2. Simulations also show that ligated VEGFR2 and phosphorylated VEGFR2 levels diverge over time following stimulation. Using this model, we identify multiple key levers that alter how VEGF binding to VEGFR2 results in different coordinated patterns of multiple downstream signaling pathways. Specifically, simulations predict that VEGF immobilization, interactions with Neuropilin-1, perturbations of VEGFR2 trafficking, and changes in expression or activity of phosphatases acting on VEGFR2 all affect the magnitude, duration, and relative strength of VEGFR2 phosphorylation on tyrosines 1175 and 1214, and they do so predictably within our single consistent model framework. Vascular endothelial growth factor (VEGF) is an important regulator of blood vessel growth. To date, therapies attempting to harness the VEGF system to promote blood vessel growth (e.g. for wound healing or ischemic disease) have achieved only limited success. To improve VEGF-based therapies, we need to better understand how VEGF promotes development of functional blood vessels. We have developed a computational model of VEGF binding to the receptor VEGFR2, trafficking of VEGFR2 through endosomal compartments in the cell, and activation of VEGFR2 on several tyrosine residues. The pattern of tyrosines activated on VEGFR2 influences cell behavior, promoting cell survival, proliferation, or migration. The combination of these cues influences the diameter of vessels, degree of branching, and leakiness of the resultant vessel network. Our model shows that changes in VEGFR2 trafficking as a result of VEGF immobilization to the extracellular matrix are sufficient to describe observed changes in the pattern of VEGFR2 activation compared to stimulation with purely soluble VEGF. This model can be used to predict how VEGF immobilization, interactions with co-receptors or proteins that deactivate VEGFR2, and changes to VEGFR2 trafficking can be tuned to promote development of functional blood vessel networks for tissue engineering applications.
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Affiliation(s)
- Lindsay Wendel Clegg
- Institute for Computational Medicine and Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, United States of America
- * E-mail:
| | - Feilim Mac Gabhann
- Institute for Computational Medicine and Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, United States of America
- Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, Maryland, United States of America
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19
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Chen X, Zhou HJ, Huang Q, Lu L, Min W. Novel action and mechanism of auranofin in inhibition of vascular endothelial growth factor receptor-3-dependent lymphangiogenesis. Anticancer Agents Med Chem 2015; 14:946-54. [PMID: 24913775 DOI: 10.2174/1871520614666140610102651] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2014] [Revised: 06/06/2014] [Accepted: 06/08/2014] [Indexed: 01/05/2023]
Abstract
Auranofin is a gold compound initially developed for the treatment of rheumatoid arthritis. Recent data suggest that auranofin has promise in the treatment of other inflammatory and proliferative diseases. However, the mechanisms of action of auranofin have not been well defined. In the present study, we identify vascular endothelial growth factor receptor-3 (VEGFR3), an endothelial cell (EC) surface receptor essential for angiogiogenesis and lymphangiogenesis, as a novel target of auranofin. In both primary EC and EC cell lines, auranofin induces downregulation of VEGFR3 in a dose-dependent manner. Auranofin at high doses (≥1 µM) decreases cellular survival protein thioredoxin reductase (TrxR2), TrxR2-dependent Trx2 and transcription factor NF-κB whereas increases stress signaling p38MAPK, leading to EC apoptosis. However, auranofin at low doses (≤0.5 µM) specifically induces downregulation of VEGFR3 and VEGFR3-mediated EC proliferation and migration, two critical steps required for in vivo lymphangiogenesis. Mechanistically, we show that auranofin-induced VEGFR3 downregulation is blocked by antioxidant N-acetyl-L-cysteine (NAC) and lysosome inhibitor chloroquine, but is promoted by proteasomal inhibitor MG132. These results suggest that auranofin induces VEGFR3 degradation through a lysosome-dependent pathway. Auranofin may be a potent therapeutic agent for the treatment of lymphangiogenesis-dependent diseases such as lymphedema and cancer metastasis.
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Affiliation(s)
| | | | | | | | - Wang Min
- Interdepartmental Program in Vascular Biology and Therapeutics, Department of Pathology, Yale University School of Medicine, 10 Amistad St., New Haven, CT 06520.
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20
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Fearnley GW, Bruns AF, Wheatcroft SB, Ponnambalam S. VEGF-A isoform-specific regulation of calcium ion flux, transcriptional activation and endothelial cell migration. Biol Open 2015; 4:731-42. [PMID: 25910937 PMCID: PMC4467193 DOI: 10.1242/bio.201410884] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Vascular endothelial growth factor A (VEGF-A) regulates many aspects of vascular physiology such as cell migration, proliferation, tubulogenesis and cell-cell interactions. Numerous isoforms of VEGF-A exist but their physiological significance is unclear. Here we evaluated two different VEGF-A isoforms and discovered differential regulation of cytosolic calcium ion flux, transcription factor localisation and endothelial cell response. Analysis of VEGF-A isoform-specific stimulation of VEGFR2-dependent signal transduction revealed differential capabilities for isoform activation of multiple signal transduction pathways. VEGF-A165 treatment promoted increased phospholipase Cγ1 phosphorylation, which was proportional to the subsequent rise in cytosolic calcium ions, in comparison to cells treated with VEGF-A121. A major consequence of this VEGF-A isoform-specific calcium ion flux in endothelial cells is differential dephosphorylation and subsequent nuclear translocation of the transcription factor NFATc2. Using reverse genetics, we discovered that NFATc2 is functionally required for VEGF-A-stimulated endothelial cell migration but not tubulogenesis. This work presents a new mechanism for understanding how VEGF-A isoforms program complex cellular outputs by converting signal transduction pathways into transcription factor redistribution to the nucleus, as well as defining a novel role for NFATc2 in regulating the endothelial cell response.
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Affiliation(s)
- Gareth W Fearnley
- Endothelial Cell Biology Unit, School of Molecular & Cellular Biology, LIGHT Laboratories, University of Leeds, Leeds LS2 9JT, UK
| | - Alexander F Bruns
- Division of Cardiovascular & Diabetes Research, Faculty of Medicine & Health, LIGHT Laboratories, University of Leeds, Leeds LS2 9JT, UK
| | - Stephen B Wheatcroft
- Division of Cardiovascular & Diabetes Research, Faculty of Medicine & Health, LIGHT Laboratories, University of Leeds, Leeds LS2 9JT, UK
| | - Sreenivasan Ponnambalam
- Endothelial Cell Biology Unit, School of Molecular & Cellular Biology, LIGHT Laboratories, University of Leeds, Leeds LS2 9JT, UK
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21
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Smith RJ, Koobatian MT, Shahini A, Swartz DD, Andreadis ST. Capture of endothelial cells under flow using immobilized vascular endothelial growth factor. Biomaterials 2015; 51:303-312. [PMID: 25771020 PMCID: PMC4361797 DOI: 10.1016/j.biomaterials.2015.02.025] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Revised: 01/27/2015] [Accepted: 02/01/2015] [Indexed: 02/09/2023]
Abstract
We demonstrate the ability of immobilized vascular endothelial growth factor (VEGF) to capture endothelial cells (EC) with high specificity under fluid flow. To this end, we engineered a surface consisting of heparin bound to poly-L-lysine to permit immobilization of VEGF through the C-terminal heparin-binding domain. The immobilized growth factor retained its biological activity as shown by proliferation of EC and prolonged activation of KDR signaling. Using a microfluidic device we assessed the ability to capture EC under a range of shear stresses from low (0.5 dyne/cm2) to physiological (15 dyne/cm2). Capture was significant for all shear stresses tested. Immobilized VEGF was highly selective for EC as evidenced by significant capture of human umbilical vein and ovine pulmonary artery EC but no capture of human dermal fibroblasts, human hair follicle derived mesenchymal stem cells, or mouse fibroblasts. Further, VEGF could capture EC from mixtures with non-EC under low and high shear conditions as well as from complex fluids like whole human blood under high shear. Our findings may have far reaching implications, as they suggest that VEGF could be used to promote endothelialization of vascular grafts or neovascularization of implanted tissues by rare but continuously circulating EC.
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Affiliation(s)
- Randall J Smith
- Department of Biomedical Engineering, University at Buffalo, State University of New York, Amherst, NY 14260-4200, USA
| | - Maxwell T Koobatian
- Department of Physiology and Biophysics, University at Buffalo, State University of New York, Amherst, NY 14260-4200, USA
| | - Aref Shahini
- Department of Chemical and Biological Engineering, University at Buffalo, State University of New York, Amherst, NY 14260-4200, USA
| | - Daniel D Swartz
- Department of Physiology and Biophysics, University at Buffalo, State University of New York, Amherst, NY 14260-4200, USA; Department of Pediatrics, Women and Children's Hospital of Buffalo, University at Buffalo, State University of New York, Amherst, NY 14260-4200, USA; Center of Excellence in Bioinformatics and Life Sciences, University at Buffalo, State University of New York, Amherst, NY 14260-4200, USA
| | - Stelios T Andreadis
- Department of Chemical and Biological Engineering, University at Buffalo, State University of New York, Amherst, NY 14260-4200, USA; Department of Biomedical Engineering, University at Buffalo, State University of New York, Amherst, NY 14260-4200, USA; Center of Excellence in Bioinformatics and Life Sciences, University at Buffalo, State University of New York, Amherst, NY 14260-4200, USA.
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22
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Fearnley GW, Odell AF, Latham AM, Mughal NA, Bruns AF, Burgoyne NJ, Homer-Vanniasinkam S, Zachary IC, Hollstein MC, Wheatcroft SB, Ponnambalam S. VEGF-A isoforms differentially regulate ATF-2-dependent VCAM-1 gene expression and endothelial-leukocyte interactions. Mol Biol Cell 2014; 25:2509-21. [PMID: 24966171 PMCID: PMC4142621 DOI: 10.1091/mbc.e14-05-0962] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
VEGF-A isoforms differentially stimulate endothelial VCAM-1 gene expression via an ERK1/2 protein kinase and ATF-2 transcription factor–dependent mechanism. Such signal transduction enables VEGF-A isoform–specific stimulation of leukocyte binding to endothelial cells, explaining how inflammation could be differentially regulated. Vascular endothelial growth factor A (VEGF-A) regulates many aspects of vascular physiology. VEGF-A stimulates signal transduction pathways that modulate endothelial outputs such as cell migration, proliferation, tubulogenesis, and cell–cell interactions. Multiple VEGF-A isoforms exist, but the biological significance of this is unclear. Here we analyzed VEGF-A isoform–specific stimulation of VCAM-1 gene expression, which controls endothelial–leukocyte interactions, and show that this is dependent on both ERK1/2 and activating transcription factor-2 (ATF-2). VEGF-A isoforms showed differential ERK1/2 and p38 MAPK phosphorylation kinetics. A key feature of VEGF-A isoform–specific ERK1/2 activation and nuclear translocation was increased phosphorylation of ATF-2 on threonine residue 71 (T71). Using reverse genetics, we showed ATF-2 to be functionally required for VEGF-A–stimulated endothelial VCAM-1 gene expression. ATF-2 knockdown blocked VEGF-A–stimulated VCAM-1 expression and endothelial–leukocyte interactions. ATF-2 was also required for other endothelial cell outputs, such as cell migration and tubulogenesis. In contrast, VCAM-1 was essential only for promoting endothelial–leukocyte interactions. This work presents a new paradigm for understanding how soluble growth factor isoforms program complex cellular outputs and responses by modulating signal transduction pathways.
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Affiliation(s)
- Gareth W Fearnley
- Endothelial Cell Biology Unit, School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Adam F Odell
- Endothelial Cell Biology Unit, School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Antony M Latham
- Endothelial Cell Biology Unit, School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Nadeem A Mughal
- Endothelial Cell Biology Unit, School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, United KingdomLeeds Vascular Institute, Leeds General Infirmary, Leeds LS1 3EX, United Kingdom
| | - Alexander F Bruns
- Division of Cardiovascular and Diabetes Research, Faculty of Medicine and Health, LIGHT Laboratories, University of Leeds, Leeds LS2 9JT, United Kingdom
| | | | | | - Ian C Zachary
- Division of Cardiovascular Biology and Medicine, Rayne Institute, University College London, London, United Kingdom
| | | | - Stephen B Wheatcroft
- Division of Cardiovascular and Diabetes Research, Faculty of Medicine and Health, LIGHT Laboratories, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Sreenivasan Ponnambalam
- Endothelial Cell Biology Unit, School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
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23
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Endosome-to-Plasma Membrane Recycling of VEGFR2 Receptor Tyrosine Kinase Regulates Endothelial Function and Blood Vessel Formation. Cells 2014; 3:363-85. [PMID: 24785348 PMCID: PMC4092869 DOI: 10.3390/cells3020363] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Revised: 03/04/2014] [Accepted: 03/17/2014] [Indexed: 12/13/2022] Open
Abstract
Rab GTPases are implicated in endosome-to-plasma membrane recycling, but how such membrane traffic regulators control vascular endothelial growth factor receptor 2 (VEGFR2/KDR) dynamics and function are not well understood. Here, we evaluated two different recycling Rab GTPases, Rab4a and Rab11a, in regulating endothelial VEGFR2 trafficking and signalling with implications for endothelial cell migration, proliferation and angiogenesis. In primary endothelial cells, VEGFR2 displays co-localisation with Rab4a, but not Rab11a GTPase, on early endosomes. Expression of a guanosine diphosphate (GDP)-bound Rab4a S22N mutant caused increased VEGFR2 accumulation in endosomes. TfR and VEGFR2 exhibited differences in endosome-to-plasma membrane recycling in the presence of chloroquine. Depletion of Rab4a, but not Rab11a, levels stimulated VEGF-A-dependent intracellular signalling. However, depletion of either Rab4a or Rab11a levels inhibited VEGF-A-stimulated endothelial cell migration. Interestingly, depletion of Rab4a levels stimulated VEGF-A-regulated endothelial cell proliferation. Rab4a and Rab11a were also both required for endothelial tubulogenesis. Evaluation of a transgenic zebrafish model showed that both Rab4 and Rab11a are functionally required for blood vessel formation and animal viability. Rab-dependent endosome-to-plasma membrane recycling of VEGFR2 is important for intracellular signalling, cell migration and proliferation during angiogenesis.
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Engelhardt S, Patkar S, Ogunshola OO. Cell-specific blood-brain barrier regulation in health and disease: a focus on hypoxia. Br J Pharmacol 2014; 171:1210-30. [PMID: 24641185 PMCID: PMC3952799 DOI: 10.1111/bph.12489] [Citation(s) in RCA: 103] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Revised: 10/02/2013] [Accepted: 10/16/2013] [Indexed: 01/16/2023] Open
Abstract
The blood-brain barrier (BBB) is a complex vascular structure consisting of microvascular endothelial cells that line the vessel wall, astrocyte end-feet, pericytes, as well as the basal lamina. BBB cells act in concert to maintain the characteristic impermeable and low paracellular flux of the brain vascular network, thus ensuring a homeostatic neuronal environment. Alterations in BBB stability that occur during injury have dire consequences on disease progression and it is clear that BBB cell-specific responses, positive or negative, must make a significant contribution to injury outcome. Reduced oxygenation, or hypoxia, is a characteristic of many brain diseases that significantly increases barrier permeability. Recent data suggest that hypoxia-inducible factor (HIF-1), the master regulator of the hypoxic response, probably mediates many hypoxic effects either directly or indirectly via its target genes. This review discusses current knowledge of physiological cell-specific regulation of barrier function, their responses to hypoxia as well as consequences of hypoxic- and HIF-1-mediated mechanisms on barrier integrity during select brain diseases. In the final sections, the potential of current advances in targeting HIF-1 as a therapeutic strategy will be overviewed.
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Affiliation(s)
- S Engelhardt
- Institute of Veterinary Physiology, University of ZurichZurich, Switzerland
| | - S Patkar
- Institute of Veterinary Physiology, University of ZurichZurich, Switzerland
| | - O O Ogunshola
- Institute of Veterinary Physiology, University of ZurichZurich, Switzerland
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Zhou HJ, Chen X, Huang Q, Liu R, Zhang H, Wang Y, Jin Y, Liang X, Lu L, Xu Z, Min W. AIP1 mediates vascular endothelial cell growth factor receptor-3-dependent angiogenic and lymphangiogenic responses. Arterioscler Thromb Vasc Biol 2014; 34:603-15. [PMID: 24407031 DOI: 10.1161/atvbaha.113.303053] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE To investigate the novel function of ASK1-interacting protein-1 (AIP1) in vascular endothelial cell growth factor receptor (VEGFR)-3 signaling, and VEGFR-3-dependent angiogenesis and lymphangiogenesis. APPROACH AND RESULTS AIP1, a signaling scaffold protein, is highly expressed in the vascular endothelium. We have previously reported that AIP1 functions as an endogenous inhibitor in pathological angiogenesis by blocking VEGFR-2 activity. Surprisingly, here we observe that mice with a global deletion of AIP1-knockout mice (AIP1-KO) exhibit reduced retinal angiogenesis with less sprouting and fewer branches. Vascular endothelial cell (but not neuronal)-specific deletion of AIP1 causes similar defects in retinal angiogenesis. The reduced retinal angiogenesis correlates with reduced expression in VEGFR-3 despite increased VEGFR-2 levels in AIP1-KO retinas. Consistent with the reduced expression of VEGFR-3, AIP1-KO show delayed developmental lymphangiogenesis in neonatal skin and mesentery, and mount weaker VEGF-C-induced cornea lymphangiogenesis. In vitro, human lymphatic endothelial cells with AIP1 small interfering RNA knockdown, retinal endothelial cells, and lymphatic endothelial cells isolated from AIP1-KO all show attenuated VEGF-C-induced VEGFR-3 signaling. Mechanistically, we demonstrate that AIP1 via vegfr-3-specific miR-1236 increases VEGFR-3 protein expression and that, by directly binding to VEGFR-3, it enhances VEGFR-3 endocytosis and stability. CONCLUSION Our in vivo and in vitro results provide the first insight into the mechanism by which AIP1 mediates VEGFR-3-dependent angiogenic and lymphangiogenic signaling.
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Affiliation(s)
- Huanjiao Jenny Zhou
- From the Interdepartmental Program in Vascular Biology and Therapeutics, Yale University School of Medicine, New Haven, CT (H.J.Z., X.C., Q.H., H.Z., Y.W., Y.J., W.M.); State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China (H.J.Z., X.C., X.L., L.L.); Diseases of the Aorta Lab, Center for the Endothelium, Vascular Biology Program, Centenary Institute and University of Sydney, Sydney, Australia (R.L.); Department of Ophthalmology, Guangzhou General Hospital of Guangzhou Military Command, Guangzhou, China (Z.X.)
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Abstract
The function of vascular endothelial growth factor (VEGF) in cancer is not limited to angiogenesis and vascular permeability. VEGF-mediated signalling occurs in tumour cells, and this signalling contributes to key aspects of tumorigenesis, including the function of cancer stem cells and tumour initiation. In addition to VEGF receptor tyrosine kinases, the neuropilins are crucial for mediating the effects of VEGF on tumour cells, primarily because of their ability to regulate the function and the trafficking of growth factor receptors and integrins. This has important implications for our understanding of tumour biology and for the development of more effective therapeutic approaches.
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Affiliation(s)
- Hira Lal Goel
- Department of Cancer Biology, University of Massachusetts Medical School, 55 Lake Avenue North, Worcester, Massachusetts 01655, USA
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Tan WH, Popel AS, Mac Gabhann F. Computational model of VEGFR2 pathway to ERK activation and modulation through receptor trafficking. Cell Signal 2013; 25:2496-510. [PMID: 23993967 DOI: 10.1016/j.cellsig.2013.08.015] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Accepted: 08/24/2013] [Indexed: 01/09/2023]
Abstract
Vascular Endothelial Growth Factor (VEGF) signal transduction is central to angiogenesis in development and in pathological conditions such as cancer, retinopathy and ischemic diseases. We constructed and validated a computational model of VEGFR2 trafficking and signaling, to study the role of receptor trafficking kinetics in modulating ERK phosphorylation in VEGF-stimulated endothelial cells. Trafficking parameters were optimized and validated against four previously published in vitro experiments. Based on these parameters, model simulations demonstrated interesting behaviors that may be highly relevant to understanding VEGF signaling in endothelial cells. First, at moderate VEGF doses, VEGFR2 phosphorylation and ERK phosphorylation are related in a log-linear fashion, with a stable duration of ERK activation; but with higher VEGF stimulation, phosphoERK becomes saturated, and its duration increases. Second, a large endosomal fraction of VEGFR2 makes the ERK activation reaction network less sensitive to perturbations in VEGF dosage. Third, extracellular-matrix-bound VEGF binds and activates VEGFR2, but by internalizing at a slower rate, matrix-bound VEGF-induced intracellular ERK phosphorylation is predicted to be greater in magnitude and more sustained, in agreement with experimental evidence. Fourth, different endothelial cell types appear to have different trafficking rates, which result in different levels of endosomal receptor localization and different ERK response profiles.
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Affiliation(s)
- Wan Hua Tan
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, 720 Rutland Ave., Baltimore, MD 21205, USA
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