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Wu Z, Liu Q, Zhao Y, Fang C, Zheng W, Zhao Z, Zhang N, Yang X. Rhogef17: A novel target for endothelial barrier function. Biomed Pharmacother 2024; 170:115983. [PMID: 38134633 DOI: 10.1016/j.biopha.2023.115983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 11/29/2023] [Accepted: 12/02/2023] [Indexed: 12/24/2023] Open
Abstract
ARHGEF17 encodes the protein RhoGEF17, which is highly expressed in vascular endothelial cells. It is a guanine nucleotide exchange factor (GEF) that accelerates the exchange of GDP with GTP on many small GTPases through its Dbl homology (DH) domain, enabling the activation of Rho-GTPases such as RhoA, RhoB, and RhoC. Rho GTPase-regulated changes in the actin cytoskeleton and cell adhesion kinetics are the main mechanisms mediating many endothelial cell (EC) alterations, including cell morphology, migration, and division changes, which profoundly affect EC barrier function. This review focuses on ARHGEF17 expression, activation and biological functions in ECs, linking its regulation of cellular morphology, migration, mitosis and other cellular behaviors to disease onset and progression. Understanding ARHGEF17 mechanisms of action will contribute to the design of therapeutic approaches targeting RhoGEF17, a potential drug target for the treatment of various endothelium-related diseases, Such as vascular inflammation, carcinogenesis and transendothelial metastasis of tumors.
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Affiliation(s)
- Zhuolin Wu
- Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, China; Tianjin Neurological Institute, Key Laboratory of Post-Neuroinjury Neuro-Repair and Regeneration in Central Nervous System, Ministry of Education and Tianjin City, Tianjin Medical University General Hospital, Tianjin, China
| | - Quanlei Liu
- Department of Neurosurgery, Capital Medical University, Xuanwu Hospital, Beijing, China
| | - Yan Zhao
- Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, China; Tianjin Neurological Institute, Key Laboratory of Post-Neuroinjury Neuro-Repair and Regeneration in Central Nervous System, Ministry of Education and Tianjin City, Tianjin Medical University General Hospital, Tianjin, China
| | | | - Wen Zheng
- Zhejiang University of Technology, Hangzhou, Zhejiang, China
| | - Zilin Zhao
- Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, China; Tianjin Neurological Institute, Key Laboratory of Post-Neuroinjury Neuro-Repair and Regeneration in Central Nervous System, Ministry of Education and Tianjin City, Tianjin Medical University General Hospital, Tianjin, China
| | - Nai Zhang
- Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, China
| | - Xinyu Yang
- Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, China; Tianjin Neurological Institute, Key Laboratory of Post-Neuroinjury Neuro-Repair and Regeneration in Central Nervous System, Ministry of Education and Tianjin City, Tianjin Medical University General Hospital, Tianjin, China.
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2
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Sun Y, Xu C, Jiang Z, Jiang X. DEF6(differentially exprehomolog) exacerbates pathological cardiac hypertrophy via RAC1. Cell Death Dis 2023; 14:483. [PMID: 37524688 PMCID: PMC10390462 DOI: 10.1038/s41419-023-05948-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 06/15/2023] [Accepted: 07/04/2023] [Indexed: 08/02/2023]
Abstract
Pathological cardiac hypertrophy involves multiple regulators and several signal transduction pathways. Currently, the mechanisms of it are not well understood. Differentially expressed in FDCP 6 homolog (DEF6) was reported to participate in immunity, bone remodeling, and cancers. The effects of DEF6 on pathological cardiac hypertrophy, however, have not yet been fully characterized. We initially determined the expression profile of DEF6 and found that DEF6 was upregulated in hypertrophic hearts and cardiomyocytes. Our in vivo results revealed that DEF6 deficiency in mice alleviated transverse aortic constriction (TAC)-induced cardiac hypertrophy, fibrosis, dilation and dysfunction of left ventricle. Conversely, cardiomyocyte-specific DEF6-overexpression aggravated the hypertrophic phenotype in mice under chronic pressure overload. Similar to the animal experiments, the in vitro data showed that adenovirus-mediated knockdown of DEF6 remarkably inhibited phenylephrine (PE)-induced cardiomyocyte hypertrophy, whereas DEF6 overexpression exerted the opposite effects. Mechanistically, exploration of the signal pathways showed that the mitogen-activated extracellular signal-regulated kinase 1/2 (MEK1/2)-extracellular signal-regulated kinase 1/2 (ERK1/2) cascade might be involved in the prohypertrophic effect of DEF6. Coimmunoprecipitation and GST (glutathione S-transferase) pulldown analyses demonstrated that DEF6 can directly interact with small GTPase Ras-related C3 botulinum toxin substrate 1 (Rac1), and the Rac1 activity assay revealed that the activity of Rac1 is altered with DEF6 expression in TAC-cardiac hypertrophy and PE-triggered cardiomyocyte hypertrophy. In the end, western blot and rescue experiments using Rac1 inhibitor NSC23766 and the constitutively active mutant Rac1(G12V) verified the requirement of Rac1 and MEK1/2-ERK1/2 activation for DEF6-mediated pathological cardiac hypertrophy. Our study substantiates that DEF6 acts as a deleterious regulator of cardiac hypertrophy by activating the Rac1 and MEK1/2-ERK1/2 signaling pathways, and suggests that DEF6 may be a potential treatment target for heart failure.
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Affiliation(s)
- Yan Sun
- Department of Gastroenterology, Shengjing Hospital of China Medical University, 110022, Shenyang, Liaoning Province, China
| | - Changlu Xu
- Department of Cardiology, Shengjing Hospital of China Medical University, 110022, Shenyang, Liaoning Province, China
| | - Zhongxiu Jiang
- Department of Oncology, Shengjing Hospital of China Medical University, 110022, Shenyang, Liaoning Province, China
| | - Xi Jiang
- Department of Cardiology, Shengjing Hospital of China Medical University, 110022, Shenyang, Liaoning Province, China.
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3
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Long M, Cui Y, Pang X, Wang B, He J, Zhang Q, Yu S, Bai X. Changes in arterial blood vessels and VEGF and Ang-1 expression in pregnant and non-pregnant yak uterine caruncle. Reprod Domest Anim 2022; 57:1554-1563. [PMID: 36005750 DOI: 10.1111/rda.14232] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 07/30/2022] [Accepted: 08/21/2022] [Indexed: 11/29/2022]
Abstract
We investigated the structural features of arterial blood vessels in yak uterine caruncle and the effects of the expression of vascular regulation-related factors on angiogenesis in pregnant and non-pregnant yak uterus. Three-dimensional specimens of the uterine artery of non-pregnant and pregnant yaks were produced to observe and measure the distribution characteristics and number of arterial vessels in the uterus and caruncle in the two periods. The uterine caruncle structure was observed and analyzed by hematoxylin-eosin staining. The expression features of vascular endothelial growth factor (VEGF) and angiopoietin-1 (Ang-1) in the uterine caruncle were detected with immunohistochemistry, quantitative real-time PCR (qRT-PCR), and western blotting. The length and number of blood vessels in the caruncle were increased, the degree of curvature was decreased, and the folding was more complicated during pregnancy as compared with that during non-pregnancy. The immunohistochemical results demonstrated that VEGF and Ang-1 were mainly expressed strongly in the mucosal epithelial cytoplasm. The glandular lumen of the uterine gland, lymphocytes, and the media and adventitia of blood vessels are widely distributed, and they are all positive. VEGF and Ang-1 mRNA and protein levels were highest in pregnancy, followed by that in the luteal phase and in the follicular phase, and three stages were significantly different (p < 0.05). These findings provide an anatomical reference and theoretical basis for improving the diagnosis and treatment of yak reproductive disorders and other diseases in high-altitude and low-oxygen environments.
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Affiliation(s)
- Min Long
- College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China
| | - Yan Cui
- College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China
| | - Xin Pang
- College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China
| | - Biao Wang
- College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China
| | - Junfeng He
- College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China
| | - Qian Zhang
- College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China
| | - Sijiu Yu
- Technology and Research Center of Gansu Province for Embryonic Engineering of Bovine and Sheep & Goat, Lanzhou, China
| | - Xuefeng Bai
- College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China
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4
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Luxen M, van Meurs M, Molema G. Unlocking the Untapped Potential of Endothelial Kinase and Phosphatase Involvement in Sepsis for Drug Treatment Design. Front Immunol 2022; 13:867625. [PMID: 35634305 PMCID: PMC9136877 DOI: 10.3389/fimmu.2022.867625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 03/28/2022] [Indexed: 11/29/2022] Open
Abstract
Sepsis is a devastating clinical condition that can lead to multiple organ failure and death. Despite advancements in our understanding of molecular mechanisms underlying sepsis and sepsis-associated multiple organ failure, no effective therapeutic treatment to directly counteract it has yet been established. The endothelium is considered to play an important role in sepsis. This review highlights a number of signal transduction pathways involved in endothelial inflammatory activation and dysregulated endothelial barrier function in response to sepsis conditions. Within these pathways – NF-κB, Rac1/RhoA GTPases, AP-1, APC/S1P, Angpt/Tie2, and VEGF/VEGFR2 – we focus on the role of kinases and phosphatases as potential druggable targets for therapeutic intervention. Animal studies and clinical trials that have been conducted for this purpose are discussed, highlighting reasons why they might not have resulted in the expected outcomes, and which lessons can be learned from this. Lastly, opportunities and challenges that sepsis and sepsis-associated multiple organ failure research are currently facing are presented, including recommendations on improved experimental design to increase the translational power of preclinical research to the clinic.
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Affiliation(s)
- Matthijs Luxen
- Department of Pathology and Medical Biology, Medical Biology Section, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
- Department of Critical Care, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
- *Correspondence: Matthijs Luxen,
| | - Matijs van Meurs
- Department of Pathology and Medical Biology, Medical Biology Section, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
- Department of Critical Care, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Grietje Molema
- Department of Pathology and Medical Biology, Medical Biology Section, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
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5
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Kemp SS, Lin PK, Sun Z, Castaño MA, Yrigoin K, Penn MR, Davis GE. Molecular basis for pericyte-induced capillary tube network assembly and maturation. Front Cell Dev Biol 2022; 10:943533. [PMID: 36072343 PMCID: PMC9441561 DOI: 10.3389/fcell.2022.943533] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 07/25/2022] [Indexed: 11/13/2022] Open
Abstract
Here we address the functional importance and role of pericytes in capillary tube network assembly, an essential process that is required for vascularized tissue development, maintenance, and health. Healthy capillaries may be directly capable of suppressing human disease. Considerable advances have occurred in our understanding of the molecular and signaling requirements controlling EC lumen and tube formation in 3D extracellular matrices. A combination of SCF, IL-3, SDF-1α, FGF-2 and insulin ("Factors") in conjunction with integrin- and MT1-MMP-induced signaling are required for EC sprouting behavior and tube formation under serum-free defined conditions. Pericyte recruitment to the abluminal EC tube surface results in elongated and narrow tube diameters and deposition of the vascular basement membrane. In contrast, EC tubes in the absence of pericytes continue to widen and shorten over time and fail to deposit basement membranes. Pericyte invasion, recruitment and proliferation in 3D matrices requires the presence of ECs. A detailed analysis identified that EC-derived PDGF-BB, PDGF-DD, ET-1, HB-EGF, and TGFβ1 are necessary for pericyte recruitment, proliferation, and basement membrane deposition. Blockade of these individual factors causes significant pericyte inhibition, but combined blockade profoundly interferes with these events, resulting in markedly widened EC tubes without basement membranes, like when pericytes are absent.
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Affiliation(s)
- Scott S Kemp
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida School of Medicine, Tampa, FL, United States
| | - Prisca K Lin
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida School of Medicine, Tampa, FL, United States
| | - Zheying Sun
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida School of Medicine, Tampa, FL, United States
| | - Maria A Castaño
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida School of Medicine, Tampa, FL, United States
| | - Ksenia Yrigoin
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida School of Medicine, Tampa, FL, United States
| | - Marlena R Penn
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida School of Medicine, Tampa, FL, United States
| | - George E Davis
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida School of Medicine, Tampa, FL, United States
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6
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Binding of the Andes Virus Nucleocapsid Protein to RhoGDI Induces the Release and Activation of the Permeability Factor RhoA. J Virol 2021; 95:e0039621. [PMID: 34133221 DOI: 10.1128/jvi.00396-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Andes virus (ANDV) nonlytically infects pulmonary microvascular endothelial cells (PMECs), causing acute pulmonary edema termed hantavirus pulmonary syndrome (HPS). In HPS patients, virtually every PMEC is infected; however, the mechanism by which ANDV induces vascular permeability and edema remains to be resolved. The ANDV nucleocapsid (N) protein activates the GTPase RhoA in primary human PMECs, causing VE-cadherin internalization from adherens junctions and PMEC permeability. We found that ANDV N protein failed to bind RhoA but coprecipitates RhoGDI (Rho GDP dissociation inhibitor), the primary RhoA repressor that normally sequesters RhoA in an inactive state. ANDV N protein selectively binds the RhoGDI C terminus (residues 69 to 204) but fails to form ternary complexes with RhoA or inhibit RhoA binding to the RhoGDI N terminus (residues 1 to 69). However, we found that ANDV N protein uniquely inhibits RhoA binding to an S34D phosphomimetic RhoGDI mutant. Hypoxia and vascular endothelial growth factor (VEGF) increase RhoA-induced PMEC permeability by directing protein kinase Cα (PKCα) phosphorylation of S34 on RhoGDI. Collectively, ANDV N protein alone activates RhoA by sequestering and reducing RhoGDI available to suppress RhoA. In response to hypoxia and VEGF-activated PKCα, ANDV N protein additionally directs the release of RhoA from S34-phosphorylated RhoGDI, synergistically activating RhoA and PMEC permeability. These findings reveal a fundamental edemagenic mechanism that permits ANDV to amplify PMEC permeability in hypoxic HPS patients. Our results rationalize therapeutically targeting PKCα and opposing protein kinase A (PKA) pathways that control RhoGDI phosphorylation as a means of resolving ANDV-induced capillary permeability, edema, and HPS. IMPORTANCE HPS-causing hantaviruses infect pulmonary endothelial cells (ECs), causing vascular leakage, pulmonary edema, and a 35% fatal acute respiratory distress syndrome (ARDS). Hantaviruses do not lyse or disrupt the endothelium but dysregulate normal EC barrier functions and increase hypoxia-directed permeability. Our findings reveal a novel underlying mechanism of EC permeability resulting from ANDV N protein binding to RhoGDI, a regulatory protein that normally maintains edemagenic RhoA in an inactive state and inhibits EC permeability. ANDV N sequesters RhoGDI and enhances the release of RhoA from S34-phosphorylated RhoGDI. These findings indicate that ANDV N induces the release of RhoA from PKC-phosphorylated RhoGDI, synergistically enhancing hypoxia-directed RhoA activation and PMEC permeability. Our data suggest inhibiting PKC and activating PKA phosphorylation of RhoGDI as mechanisms of inhibiting ANDV-directed EC permeability and therapeutically restricting edema in HPS patients. These findings may be broadly applicable to other causes of ARDS.
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7
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Lai Y, Zhao A, Tan M, Yang M, Lin Y, Li S, Song J, Zheng H, Zhu Z, Liu D, Liu C, Li L, Yang G. DOCK5 regulates energy balance and hepatic insulin sensitivity by targeting mTORC1 signaling. EMBO Rep 2020; 21:e49473. [PMID: 31885214 PMCID: PMC7001503 DOI: 10.15252/embr.201949473] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 11/14/2019] [Accepted: 11/29/2019] [Indexed: 12/25/2022] Open
Abstract
The dedicator of cytokinesis 5 (DOCK5) is associated with obesity. However, the mechanism by which DOCK5 contributes to obesity remains completely unknown. Here, we show that hepatic DOCK5 expression significantly decreases at a state of insulin resistance (IR). Deletion of DOCK5 in mice reduces energy expenditure, promotes obesity, augments IR, dysregulates glucose metabolism, and activates the mTOR (Raptor)/S6K1 pathway under a high-fat diet (HFD). The overexpression of DOCK5 in hepatocytes inhibits gluconeogenic gene expression and increases the level of insulin receptor (InsR) and Akt phosphorylation. DOCK5 overexpression also inhibits mTOR/S6K1 phosphorylation and decreases the level of raptor protein expression. The opposite effects were observed in DOCK5-deficient hepatocytes. Importantly, in liver-specific Raptor knockout mice and associated hepatocytes, the effects of an adeno-associated virus (AAV8)- or adenovirus-mediated DOCK5 knockdown on glucose metabolism and insulin signaling are largely eliminated. Additionally, DOCK5-Raptor interaction is indispensable for the DOCK5-mediated regulation of hepatic glucose production (HGP). Therefore, DOCK5 acts as a regulator of Raptor to control hepatic insulin activity and glucose homeostasis.
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Affiliation(s)
- Yerui Lai
- Department of EndocrinologyThe Second Affiliated HospitalChongqing Medical UniversityChongqingChina
| | - Anjiang Zhao
- The Key Laboratory of Laboratory Medical Diagnostics in the Ministry of Education and Department of Clinical BiochemistryCollege of Laboratory MedicineChongqing Medical UniversityChongqingChina
| | - Minghong Tan
- Department of EndocrinologyThe Second Affiliated HospitalChongqing Medical UniversityChongqingChina
| | - Mengliu Yang
- Department of EndocrinologyThe Second Affiliated HospitalChongqing Medical UniversityChongqingChina
- School of Biomedical SciencesThe University of QueenslandBrisbaneQldAustralia
| | - Yao Lin
- The Key Laboratory of Laboratory Medical Diagnostics in the Ministry of Education and Department of Clinical BiochemistryCollege of Laboratory MedicineChongqing Medical UniversityChongqingChina
| | - Shengbing Li
- Department of EndocrinologyThe Second Affiliated HospitalChongqing Medical UniversityChongqingChina
| | - Jinlin Song
- Chongqing Key Laboratory for oral Diseases and Biomedical ScienceCollege of StomatologyChongqing Medical UniversityChongqingChina
| | - Hongting Zheng
- Department of EndocrinologyXinqiao HospitalThird Military Medical UniversityChongqingChina
| | - Zhiming Zhu
- Department of Hypertension and EndocrinologyDaping HospitalChongqing Institute of HypertensionThird Military Medical UniversityChongqingChina
| | - Dongfang Liu
- Department of EndocrinologyThe Second Affiliated HospitalChongqing Medical UniversityChongqingChina
| | - Chaohong Liu
- Department of Pathogen BiologySchool of Basic MedicineHuazhong University of Science and TechnologyWuhanChina
| | - Ling Li
- Department of EndocrinologyThe Second Affiliated HospitalChongqing Medical UniversityChongqingChina
| | - Gangyi Yang
- Department of EndocrinologyThe Second Affiliated HospitalChongqing Medical UniversityChongqingChina
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8
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Xu T, He BS, Pan B, Pan YQ, Sun HL, Liu XX, Xu XN, Chen XX, Zeng KX, Xu M, Wang SK. MiR-142-3p functions as a tumor suppressor by targeting RAC1/PAK1 pathway in breast cancer. J Cell Physiol 2019; 235:4928-4940. [PMID: 31674013 DOI: 10.1002/jcp.29372] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Accepted: 10/07/2019] [Indexed: 12/24/2022]
Abstract
MicroRNA-142-3p (miR-142-3p) was previously investigated in various cancers, whereas, it's role in breast cancer (BC) remains far from understood. In this study, we found that miR-142-3p was markedly decreased both in cell lines and BC tumor tissues. Elevated miR-142-3p expression suppressed growth and metastasis of BC cell lines via gain-of-function assay in vitro and in vivo. Mechanistically, miR-142-3p could regulate the ras-related C3 botulinum toxin substrate 1 (RAC1) expression in protein level, which simultaneously suppressed the epithelial-to-mesenchymal transition related protein levels and the activity of PAK1 phosphorylation, respectively. In addition, rescue experiments revealed RAC1 overexpression could reverse tumor-suppressive role of miR-142-3p. Our results showed miR-142-3p could function as a tumor suppressor via targeting RAC1/PAK1 pathway in BC, suggesting a potent therapeutic target for BC treatment.
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Affiliation(s)
- Tao Xu
- General Clinical Research Center, Nanjing First Hospital, Nanjing Medical University, Nanjing, China
| | - Bang-Shun He
- General Clinical Research Center, Nanjing First Hospital, Nanjing Medical University, Nanjing, China
| | - Bei Pan
- General Clinical Research Center, Nanjing First Hospital, Nanjing Medical University, Nanjing, China
| | - Yu-Qin Pan
- General Clinical Research Center, Nanjing First Hospital, Nanjing Medical University, Nanjing, China
| | - Hui-Ling Sun
- General Clinical Research Center, Nanjing First Hospital, Nanjing Medical University, Nanjing, China
| | - Xiang-Xiang Liu
- General Clinical Research Center, Nanjing First Hospital, Nanjing Medical University, Nanjing, China
| | - Xue-Ni Xu
- General Clinical Research Center, Nanjing First Hospital, Nanjing Medical University, Nanjing, China.,Medical College, Southeast University, Nanjing, China
| | - Xiao-Xiang Chen
- General Clinical Research Center, Nanjing First Hospital, Nanjing Medical University, Nanjing, China.,Medical College, Southeast University, Nanjing, China
| | - Kai-Xuan Zeng
- General Clinical Research Center, Nanjing First Hospital, Nanjing Medical University, Nanjing, China.,Medical College, Southeast University, Nanjing, China
| | - Mu Xu
- General Clinical Research Center, Nanjing First Hospital, Nanjing Medical University, Nanjing, China
| | - Shu-Kui Wang
- General Clinical Research Center, Nanjing First Hospital, Nanjing Medical University, Nanjing, China.,Jiangsu Collaborative Innovation Center on Cancer Personalized Medicine, Nanjing Medical University, Nanjing, China
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9
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Fischl AS, Wang X, Falcon BL, Almonte-Baldonado R, Bodenmiller D, Evans G, Stewart J, Wilson T, Hipskind P, Manro J, Uhlik MT, Chintharlapalli S, Gerald D, Alsop DC, Benjamin LE, Bhatt RS. Inhibition of Sphingosine Phosphate Receptor 1 Signaling Enhances the Efficacy of VEGF Receptor Inhibition. Mol Cancer Ther 2019; 18:856-867. [PMID: 30787172 DOI: 10.1158/1535-7163.mct-18-0548] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 10/04/2018] [Accepted: 02/04/2019] [Indexed: 01/15/2023]
Abstract
Inhibition of VEGFR signaling is an effective treatment for renal cell carcinoma, but resistance continues to be a major problem. Recently, the sphingosine phosphate (S1P) signaling pathway has been implicated in tumor growth, angiogenesis, and resistance to antiangiogenic therapy. S1P is a bioactive lipid that serves an essential role in developmental and pathologic angiogenesis via activation of the S1P receptor 1 (S1P1). S1P1 signaling counteracts VEGF signaling and is required for vascular stabilization. We used in vivo and in vitro angiogenesis models including a postnatal retinal angiogenesis model and a renal cell carcinoma murine tumor model to test whether simultaneous inhibition of S1P1 and VEGF leads to improved angiogenic inhibition. Here, we show that inhibition of S1P signaling reduces the endothelial cell barrier and leads to excessive angiogenic sprouting. Simultaneous inhibition of S1P and VEGF signaling further disrupts the tumor vascular beds, decreases tumor volume, and increases tumor cell death compared with monotherapies. These studies suggest that inhibition of angiogenesis at two stages of the multistep process may maximize the effects of antiangiogenic therapy. Together, these data suggest that combination of S1P1 and VEGFR-targeted therapy may be a useful therapeutic strategy for the treatment of renal cell carcinoma and other tumor types.
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MESH Headings
- Angiogenesis Inhibitors/pharmacology
- Animals
- Antibodies, Monoclonal/pharmacology
- Carcinoma, Renal Cell/blood supply
- Carcinoma, Renal Cell/drug therapy
- Carcinoma, Renal Cell/metabolism
- Carcinoma, Renal Cell/pathology
- Cell Line, Tumor
- Drug Therapy, Combination
- Endothelial Cells/drug effects
- Endothelial Cells/metabolism
- Female
- Humans
- Kidney Neoplasms/blood supply
- Kidney Neoplasms/drug therapy
- Kidney Neoplasms/metabolism
- Kidney Neoplasms/pathology
- Lysophospholipids/antagonists & inhibitors
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Nude
- Neovascularization, Pathologic/drug therapy
- Sphingosine/analogs & derivatives
- Sphingosine/antagonists & inhibitors
- Sphingosine-1-Phosphate Receptors/antagonists & inhibitors
- Sunitinib/pharmacology
- Treatment Outcome
- Tumor Burden/drug effects
- Vascular Endothelial Growth Factor A/pharmacology
- Vascular Endothelial Growth Factor Receptor-2/antagonists & inhibitors
- Xenograft Model Antitumor Assays
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Affiliation(s)
| | - Xiaoen Wang
- Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | | | | | | | | | | | | | | | | | | | | | | | - David C Alsop
- Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | | | - Rupal S Bhatt
- Division of Hematology and Oncology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts.
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10
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Hudson LG, Gillette JM, Kang H, Rivera MR, Wandinger-Ness A. Ovarian Tumor Microenvironment Signaling: Convergence on the Rac1 GTPase. Cancers (Basel) 2018; 10:cancers10100358. [PMID: 30261690 PMCID: PMC6211091 DOI: 10.3390/cancers10100358] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2018] [Revised: 09/25/2018] [Accepted: 09/25/2018] [Indexed: 02/06/2023] Open
Abstract
The tumor microenvironment for epithelial ovarian cancer is complex and rich in bioactive molecules that modulate cell-cell interactions and stimulate numerous signal transduction cascades. These signals ultimately modulate all aspects of tumor behavior including progression, metastasis and therapeutic response. Many of the signaling pathways converge on the small GTPase Ras-related C3 botulinum toxin substrate (Rac)1. In addition to regulating actin cytoskeleton remodeling necessary for tumor cell adhesion, migration and invasion, Rac1 through its downstream effectors, regulates cancer cell survival, tumor angiogenesis, phenotypic plasticity, quiescence, and resistance to therapeutics. In this review we discuss evidence for Rac1 activation within the ovarian tumor microenvironment, mechanisms of Rac1 dysregulation as they apply to ovarian cancer, and the potential benefits of targeting aberrant Rac1 activity in this disease. The potential for Rac1 contribution to extraperitoneal dissemination of ovarian cancer is addressed.
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Affiliation(s)
- Laurie G Hudson
- Department of Pharmaceutical Sciences, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA.
- Comprehensive Cancer Center, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA.
| | - Jennifer M Gillette
- Comprehensive Cancer Center, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA.
- Department of Pathology, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA.
| | - Huining Kang
- Comprehensive Cancer Center, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA.
- Department of Medicine, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA.
| | - Melanie R Rivera
- Comprehensive Cancer Center, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA.
- Department of Pathology, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA.
| | - Angela Wandinger-Ness
- Comprehensive Cancer Center, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA.
- Department of Pathology, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA.
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11
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Baticic Pucar L, Pernjak Pugel E, Detel D, Varljen J. Involvement of DPP IV/CD26 in cutaneous wound healing process in mice. Wound Repair Regen 2017; 25:25-40. [PMID: 27868279 DOI: 10.1111/wrr.12498] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 11/14/2016] [Indexed: 12/26/2022]
Abstract
Dipeptidyl peptidase IV (DPP IV/CD26) is a widely distributed multifunctional protein that plays a significant role in different physiological as well as pathological processes having a broad spectrum of bioactive substrates and immunomodulative properties. It has potential influence on different processes crucial for wound healing, including cell adhesion, migration, apoptosis, and extracellular matrix degradation. However, despite its known enzymatic and immunomodulative functions, limited data characterize the role of DPP IV/CD26 in cutaneous wound healing mechanisms. The aim of this study was to investigate the process of wound healing in conditions of CD26 deficiency in order to obtain better insights on the role of DPP IV/CD26 in cutaneous regeneration. Experimental wounds were made on the dorsal part of CD26 deficient (CD26-/- ) and wild-type mice (C57BL/6). The process of cutaneous wound healing was monitored on defined time schedule postwounding by macroscopic, microscopic, and biochemical analyses. Obtained results revealed a better rate of wound closure, revascularization and cell proliferation in CD26-/- mice, with enhanced local expression of hypoxia-inducible factor 1α and vascular endothelial growth factor. CD26 deficiency induced prompt macrophage recruitment at the site of skin damage but did not influence mobilization of T-cells in comparison with wild-type mice. CD26-/- mice have significantly higher values of IP-10 in serum and control skins compared with wild-type mice but values in wounds did not differ significantly on days 2, 4, and 7 of wound healing. DPP IV/CD26 activity was found to be decreased 4 days postwounding in serum and 2, 4, and 7 days postwounding in wounds of wild-type animals compared with control skins. These findings contribute to better understanding of wound healing mechanisms and could give a support in finding new therapeutic approaches for wound healing and tissue regeneration.
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Affiliation(s)
- Lara Baticic Pucar
- Department of Chemistry and Biochemistry, Faculty of Medicine, University of Rijeka, Brace Branchetta 20, Rijeka, 51000, Hrvatska-Croatia
| | - Ester Pernjak Pugel
- Department of Histology and Embryology, Faculty of Medicine, University of Rijeka, Rijeka, Hrvatska-Croatia
| | - Dijana Detel
- Department of Chemistry and Biochemistry, Faculty of Medicine, University of Rijeka, Brace Branchetta 20, Rijeka, 51000, Hrvatska-Croatia
| | - Jadranka Varljen
- Department of Chemistry and Biochemistry, Faculty of Medicine, University of Rijeka, Brace Branchetta 20, Rijeka, 51000, Hrvatska-Croatia
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12
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The Andes Virus Nucleocapsid Protein Directs Basal Endothelial Cell Permeability by Activating RhoA. mBio 2016; 7:mBio.01747-16. [PMID: 27795403 PMCID: PMC5080385 DOI: 10.1128/mbio.01747-16] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Andes virus (ANDV) predominantly infects microvascular endothelial cells (MECs) and nonlytically causes an acute pulmonary edema termed hantavirus pulmonary syndrome (HPS). In HPS patients, virtually every pulmonary MEC is infected, MECs are enlarged, and infection results in vascular leakage and highly lethal pulmonary edema. We observed that MECs infected with the ANDV hantavirus or expressing the ANDV nucleocapsid (N) protein showed increased size and permeability by activating the Rheb and RhoA GTPases. Expression of ANDV N in MECs increased cell size by preventing tuberous sclerosis complex (TSC) repression of Rheb-mTOR-pS6K. N selectively bound the TSC2 N terminus (1 to 1403) within a complex containing TSC2/TSC1/TBC1D7, and endogenous TSC2 reciprocally coprecipitated N protein from ANDV-infected MECs. TSCs normally restrict RhoA-induced MEC permeability, and we found that ANDV infection or N protein expression constitutively activated RhoA. This suggests that the ANDV N protein alone is sufficient to activate signaling pathways that control MEC size and permeability. Further, RhoA small interfering RNA, dominant-negative RhoA(N19), and the RhoA/Rho kinase inhibitors fasudil and Y27632 dramatically reduced the permeability of ANDV-infected MECs by 80 to 90%. Fasudil also reduced the bradykinin-directed permeability of ANDV and Hantaan virus-infected MECs to control levels. These findings demonstrate that ANDV activation of RhoA causes MEC permeability and reveal a potential edemagenic mechanism for ANDV to constitutively inhibit the basal barrier integrity of infected MECs. The central importance of RhoA activation in MEC permeability further suggests therapeutically targeting RhoA, TSCs, and Rac1 as potential means of resolving capillary leakage during hantavirus infections. HPS is hallmarked by acute pulmonary edema, hypoxia, respiratory distress, and the ubiquitous infection of pulmonary MECs that occurs without disrupting the endothelium. Mechanisms of MEC permeability and targets for resolving lethal pulmonary edema during HPS remain enigmatic. Our findings suggest a novel underlying mechanism of MEC dysfunction resulting from ANDV activation of the Rheb and RhoA GTPases that, respectively, control MEC size and permeability. Our studies show that inhibition of RhoA blocks ANDV-directed permeability and implicate RhoA as a potential therapeutic target for restoring capillary barrier function to the ANDV-infected endothelium. Since RhoA activation forms a downstream nexus for factors that cause capillary leakage, blocking RhoA activation is liable to restore basal capillary integrity and prevent edema amplified by tissue hypoxia and respiratory distress. Targeting the endothelium has the potential to resolve disease during symptomatic stages, when replication inhibitors lack efficacy, and to be broadly applicable to other hemorrhagic and edematous viral diseases.
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Urso E, Maffia M. Behind the Link between Copper and Angiogenesis: Established Mechanisms and an Overview on the Role of Vascular Copper Transport Systems. J Vasc Res 2015; 52:172-96. [PMID: 26484858 DOI: 10.1159/000438485] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Accepted: 07/07/2015] [Indexed: 11/19/2022] Open
Abstract
Angiogenesis critically sustains the progression of both physiological and pathological processes. Copper behaves as an obligatory co-factor throughout the angiogenic signalling cascades, so much so that a deficiency causes neovascularization to abate. Moreover, the progress of several angiogenic pathologies (e.g. diabetes, cardiac hypertrophy and ischaemia) can be tracked by measuring serum copper levels, which are being increasingly investigated as a useful prognostic marker. Accordingly, the therapeutic modulation of body copper has been proven effective in rescuing the pathological angiogenic dysfunctions underlying several disease states. Vascular copper transport systems profoundly influence the activation and execution of angiogenesis, acting as multi-functional regulators of apparently discrete pro-angiogenic pathways. This review concerns the complex relationship among copper-dependent angiogenic factors, copper transporters and common pathological conditions, with an unusual accent on the multi-faceted involvement of the proteins handling vascular copper. Functions regulated by the major copper transport proteins (CTR1 importer, ATP7A efflux pump and metallo-chaperones) include the modulation of endothelial migration and vascular superoxide, known to activate angiogenesis within a narrow concentration range. The potential contribution of prion protein, a controversial regulator of copper homeostasis, is discussed, even though its angiogenic involvement seems to be mainly associated with the modulation of endothelial motility and permeability.
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Affiliation(s)
- Emanuela Urso
- Department of Biological and Environmental Science and Technologies, University of Salento, Lecce, Italy
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14
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Porcellini S, Asperti C, Valentinis B, Tiziano E, Mangia P, Bordignon C, Rizzardi GP, Traversari C. The tumor vessel targeting agent NGR-TNF controls the different stages of the tumorigenic process in transgenic mice by distinct mechanisms. Oncoimmunology 2015; 4:e1041700. [PMID: 26451306 DOI: 10.1080/2162402x.2015.1041700] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Revised: 04/10/2015] [Accepted: 04/10/2015] [Indexed: 10/23/2022] Open
Abstract
NGR-TNF is a vascular targeting agent in advanced clinical development, coupling tumor necrosis factor-α (TNF) with the CNGRCG peptide, which targets a CD13 isoform specifically expressed by angiogenic vessels. Antitumor efficacy of NGR-TNF has been described in different transplantation tumor models. Nevertheless, the mechanism underlying its activity is not fully understood. In the wild type and in the immunodeficient (RAG-/-) RIP1-Tag2 models of multistage pancreatic carcinogenesis, we demonstrate that CD13 is highly expressed on endothelial cells of hyperplastic and angiogenic islets, whereas its expression is down regulated in tumors where it partially colocalize with pericytes. In vivo CNGRCG peptides coupled to fluorescent nanoparticles (quantum dots) bind to CD13 and colocalize with anti-CD31, in pancreatic islets. At early stage, low doses of NGR-murine (m)TNF have a direct cytotoxic effect inducing endothelial cell apoptosis, reducing vessel density and eventually inhibiting the development of angiogenic islets. At a later stage, NGR-mTNF is able to reduce tumor growth inducing vascular normalization, exclusively when treatment is carried out in the immunocompetent mice. Interestingly, NGR-mTNF-treated tumors from these mice are characterized by CD8+ T cell infiltration. At molecular level, overexpression of genes involved in vessels normalization was detected only in NGR-mTNF-treated tumors from immunocompetent mice. These findings identified a new mechanism of action of NGR-mTNF, providing support for the development of new therapeutic strategies combining chemotherapy or active/adoptive immunotherapies to low dose NGR-TNF treatment.
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Affiliation(s)
| | | | | | | | | | - Claudio Bordignon
- MolMed SpA ; Milan, Italy ; Vita-Salute San Raffaele University ; Milan, Italy
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15
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Marinković G, Heemskerk N, van Buul JD, de Waard V. The Ins and Outs of Small GTPase Rac1 in the Vasculature. J Pharmacol Exp Ther 2015; 354:91-102. [PMID: 26036474 DOI: 10.1124/jpet.115.223610] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 06/01/2015] [Indexed: 12/16/2022] Open
Abstract
The Rho family of small GTPases forms a 20-member family within the Ras superfamily of GTP-dependent enzymes that are activated by a variety of extracellular signals. The most well known Rho family members are RhoA (Ras homolog gene family, member A), Cdc42 (cell division control protein 42), and Rac1 (Ras-related C3 botulinum toxin substrate 1), which affect intracellular signaling pathways that regulate a plethora of critical cellular functions, such as oxidative stress, cellular contacts, migration, and proliferation. In this review, we describe the current knowledge on the role of GTPase Rac1 in the vasculature. Whereas most recent reviews focus on the role of vascular Rac1 in endothelial cells, in the present review we also highlight the functional involvement of Rac1 in other vascular cells types, namely, smooth muscle cells present in the media and fibroblasts located in the adventitia of the vessel wall. Collectively, this overview shows that Rac1 activity is involved in various functions within one cell type at distinct locations within the cell, and that there are overlapping but also cell type-specific functions in the vasculature. Chronically enhanced Rac1 activity seems to contribute to vascular pathology; however, Rac1 is essential to vascular homeostasis, which makes Rac1 inhibition as a therapeutic option a delicate balancing act.
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Affiliation(s)
- Goran Marinković
- Department Medical Biochemistry (G.M., V.d.W.) and Department of Molecular Cell Biology (N.H., J.D.v.B.), Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Niels Heemskerk
- Department Medical Biochemistry (G.M., V.d.W.) and Department of Molecular Cell Biology (N.H., J.D.v.B.), Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Jaap D van Buul
- Department Medical Biochemistry (G.M., V.d.W.) and Department of Molecular Cell Biology (N.H., J.D.v.B.), Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Vivian de Waard
- Department Medical Biochemistry (G.M., V.d.W.) and Department of Molecular Cell Biology (N.H., J.D.v.B.), Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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16
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Jacobo SMP, Kazlauskas A. Insulin-like growth factor 1 (IGF-1) stabilizes nascent blood vessels. J Biol Chem 2015; 290:6349-60. [PMID: 25564613 DOI: 10.1074/jbc.m114.634154] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Here we report that VEGF-A and IGF-1 differ in their ability to stabilize newly formed blood vessels and endothelial cell tubes. Although VEGF-A failed to support an enduring vascular response, IGF-1 stabilized neovessels generated from primary endothelial cells derived from various vascular beds and mouse retinal explants. In these experimental systems, destabilization/regression was driven by lysophosphatidic acid (LPA). Because previous studies have established that Erk antagonizes LPA-mediated regression, we considered whether Erk was an essential component of IGF-dependent stabilization. Indeed, IGF-1 lost its ability to stabilize neovessels when the Erk pathway was inhibited pharmacologically. Furthermore, stabilization was associated with prolonged Erk activity. In the presence of IGF-1, Erk activity persisted longer than in the presence of VEGF or LPA alone. These studies reveal that VEGF and IGF-1 can have distinct inputs in the angiogenic process. In contrast to VEGF, IGF-1 stabilizes neovessels, which is dependent on Erk activity and associated with prolonged activation.
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Affiliation(s)
- Sarah Melissa P Jacobo
- From the Department of Ophthalmology, Harvard Medical School, The Schepens Eye Research Institute and Massachusetts Eye and Ear Infirmary, Boston, Massachusetts 02115
| | - Andrius Kazlauskas
- From the Department of Ophthalmology, Harvard Medical School, The Schepens Eye Research Institute and Massachusetts Eye and Ear Infirmary, Boston, Massachusetts 02115
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17
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Davis GE, Norden PR, Bowers SLK. Molecular control of capillary morphogenesis and maturation by recognition and remodeling of the extracellular matrix: functional roles of endothelial cells and pericytes in health and disease. Connect Tissue Res 2015; 56:392-402. [PMID: 26305158 PMCID: PMC4765926 DOI: 10.3109/03008207.2015.1066781] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
This review addresses fundamental mechanisms underlying how capillaries form in three-dimensional extracellular matrices and how endothelial cells (ECs) and pericytes co-assemble to form capillary networks. In addition to playing a critical role in supplying oxygen and nutrients to tissues, recent work suggests that blood vessels supply important signals to facilitate tissue development. Here, we hypothesize that another major function of capillaries is to supply signals to suppress major disease mechanisms including inflammation, infection, thrombosis, hemorrhage, edema, ischemic injury, fibrosis, autoimmune disease and tumor growth/progression. Capillary dysfunction plays a key pathogenic role in many human diseases, and thus, this suppressing function may be attenuated and central toward the initiation and progression of disease. We describe how capillaries form through creation of EC-lined tube networks and vascular guidance tunnels in 3D extracellular matrices. Pericytes recruit to the abluminal EC tube surface within these tunnel spaces, and work together to assemble the vascular basement membrane matrix. These processes occur under serum-free conditions in 3D collagen or fibrin matrices and in response to five key growth factors which are stem cell factor, interleukin-3, stromal-derived factor-1α, fibroblast growth factor-2 and insulin. In addition, we identified a key role for EC-derived platelet-derived growth factor-BB and heparin-binding epidermal growth factor in pericyte recruitment and proliferation to promote EC-pericyte tube co-assembly and vascular basement membrane matrix deposition. A molecular understanding of capillary morphogenesis and maturation should lead to novel therapeutic strategies to repair capillary dysfunction in major human disease contexts including cancer and diabetes.
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Affiliation(s)
- George E Davis
- a Department of Medical Pharmacology and Physiology , Dalton Cardiovascular Research Center, University of Missouri School of Medicine , Columbia , MO , USA
| | - Pieter R Norden
- a Department of Medical Pharmacology and Physiology , Dalton Cardiovascular Research Center, University of Missouri School of Medicine , Columbia , MO , USA
| | - Stephanie L K Bowers
- a Department of Medical Pharmacology and Physiology , Dalton Cardiovascular Research Center, University of Missouri School of Medicine , Columbia , MO , USA
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18
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Reddy JM, Samuel FG, McConnell JA, Reddy CP, Beck BW, Hynds DL. Non-prenylatable, cytosolic Rac1 alters neurite outgrowth while retaining the ability to be activated. Cell Signal 2014; 27:630-7. [PMID: 25479592 DOI: 10.1016/j.cellsig.2014.11.033] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Revised: 11/26/2014] [Accepted: 11/27/2014] [Indexed: 12/17/2022]
Abstract
Rac1 is an important regulator of axon extension, cell migration and actin reorganization. Like all Rho guanine triphosphatases (GTPases), Rac1 is targeted to the membrane by the addition of a geranylgeranyl moiety, an action thought to result in Rac1 guanosine triphosphate (GTP) binding. However, the role that Rac1 localization plays in its activation (GTP loading) and subsequent activation of effectors is not completely clear. To address this, we developed a non-prenylatable emerald green fluorescent protein (EmGFP)-Rac1 fusion protein (EmGFP-Rac1(C189A)) and assessed how expressing this construct affected neurite outgrowth, Rac1 localization and activation in neuroblastoma cells. Expression of EmGFP-Rac1(C189A) increased localization to the cytosol and induced cell clustering while increasing neurite initiation. EmGFP-Rac1(C189A) expression also increased Rac1 activation in the cytosol, compared to cells expressing wild-type Rac1 (EmGFP-Rac1). These results suggest that activation of Rac1 may not require plasma membrane localization, potentially leading to differential activation of cytosolic signaling pathways that alter cell morphology. Understanding the consequences of differential localization and activation of Rho GTPases, including Rac1, could lead to new therapeutic targets for treating neurological disorders.
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Affiliation(s)
- Jairus M Reddy
- Texas Woman's University Department of Biology, Denton, TX 76204-5799, United States
| | - Filsy G Samuel
- Center for Research in Neurodegenerative Disease, University of Toronto, Toronto, Canada
| | - Jordan A McConnell
- Texas Woman's University Department of Biology, Denton, TX 76204-5799, United States
| | - Cristina P Reddy
- Texas Woman's University Department of Biology, Denton, TX 76204-5799, United States
| | - Brian W Beck
- Texas Woman's University Department of Biology, Denton, TX 76204-5799, United States
| | - DiAnna L Hynds
- Texas Woman's University Department of Biology, Denton, TX 76204-5799, United States.
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19
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Guignandon A, Faure C, Neutelings T, Rattner A, Mineur P, Linossier MT, Laroche N, Lambert C, Deroanne C, Nusgens B, Demets R, Colige A, Vico L. Rac1 GTPase silencing counteracts microgravity-induced effects on osteoblastic cells. FASEB J 2014; 28:4077-87. [PMID: 24903274 DOI: 10.1096/fj.14-249714] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Accepted: 05/27/2014] [Indexed: 12/12/2022]
Abstract
Bone cells exposed to real microgravity display alterations of their cytoskeleton and focal adhesions, two major mechanosensitive structures. These structures are controlled by small GTPases of the Ras homology (Rho) family. We investigated the effects of RhoA, Rac1, and Cdc42 modulation of osteoblastic cells under microgravity conditions. Human MG-63 osteoblast-like cells silenced for RhoGTPases were cultured in the automated Biobox bioreactor (European Space Agency) aboard the Foton M3 satellite and compared to replicate ground-based controls. The cells were fixed after 69 h of microgravity exposure for postflight analysis of focal contacts, F-actin polymerization, vascular endothelial growth factor (VEGF) expression, and matrix targeting. We found that RhoA silencing did not affect sensitivity to microgravity but that Rac1 and, to a lesser extent, Cdc42 abrogation was particularly efficient in counteracting the spaceflight-related reduction of the number of focal contacts [-50% in silenced, scrambled (SiScr) controls vs. -15% for SiRac1], the number of F-actin fibers (-60% in SiScr controls vs. -10% for SiRac1), and the depletion of matrix-bound VEGF (-40% in SiScr controls vs. -8% for SiRac1). Collectively, these data point out the role of the VEGF/Rho GTPase axis in mechanosensing and validate Rac1-mediated signaling pathways as potential targets for counteracting microgravity effects.
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Affiliation(s)
- Alain Guignandon
- Institute National de la Santé et de la Recherche Médicale (INSERM), Unité 1059, Laboratoire de Biologie Intégrée du Tissu Osseux, Université de Lyon, St-Etienne, France;
| | - Céline Faure
- Institute National de la Santé et de la Recherche Médicale (INSERM), Unité 1059, Laboratoire de Biologie Intégrée du Tissu Osseux, Université de Lyon, St-Etienne, France
| | - Thibaut Neutelings
- Laboratory of Connective Tissues Biology, Groupe Interdisciplinaire de Génoprotéomique Appliqué (GIGA), Université de Liège, Sart Tilman, Belgium; and
| | - Aline Rattner
- Institute National de la Santé et de la Recherche Médicale (INSERM), Unité 1059, Laboratoire de Biologie Intégrée du Tissu Osseux, Université de Lyon, St-Etienne, France
| | - Pierre Mineur
- Laboratory of Connective Tissues Biology, Groupe Interdisciplinaire de Génoprotéomique Appliqué (GIGA), Université de Liège, Sart Tilman, Belgium; and
| | - Marie-Thérèse Linossier
- Institute National de la Santé et de la Recherche Médicale (INSERM), Unité 1059, Laboratoire de Biologie Intégrée du Tissu Osseux, Université de Lyon, St-Etienne, France
| | - Norbert Laroche
- Institute National de la Santé et de la Recherche Médicale (INSERM), Unité 1059, Laboratoire de Biologie Intégrée du Tissu Osseux, Université de Lyon, St-Etienne, France
| | - Charles Lambert
- Laboratory of Connective Tissues Biology, Groupe Interdisciplinaire de Génoprotéomique Appliqué (GIGA), Université de Liège, Sart Tilman, Belgium; and
| | - Christophe Deroanne
- Laboratory of Connective Tissues Biology, Groupe Interdisciplinaire de Génoprotéomique Appliqué (GIGA), Université de Liège, Sart Tilman, Belgium; and
| | - Betty Nusgens
- Laboratory of Connective Tissues Biology, Groupe Interdisciplinaire de Génoprotéomique Appliqué (GIGA), Université de Liège, Sart Tilman, Belgium; and
| | - René Demets
- European Space Research and Technology Center (ESTEC), Human Spaceflight and Operations (HSO), Biological Science Unit (BSU), Noordwijk, The Netherlands
| | - Alain Colige
- Laboratory of Connective Tissues Biology, Groupe Interdisciplinaire de Génoprotéomique Appliqué (GIGA), Université de Liège, Sart Tilman, Belgium; and
| | - Laurence Vico
- Institute National de la Santé et de la Recherche Médicale (INSERM), Unité 1059, Laboratoire de Biologie Intégrée du Tissu Osseux, Université de Lyon, St-Etienne, France
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20
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Charpentier MS, Conlon FL. Cellular and molecular mechanisms underlying blood vessel lumen formation. Bioessays 2013; 36:251-9. [PMID: 24323945 DOI: 10.1002/bies.201300133] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The establishment of a functional vascular system requires multiple complex steps throughout embryogenesis, from endothelial cell (EC) specification to vascular patterning into venous and arterial hierarchies. Following the initial assembly of ECs into a network of cord-like structures, vascular expansion and remodeling occur rapidly through morphogenetic events including vessel sprouting, fusion, and pruning. In addition, vascular morphogenesis encompasses the process of lumen formation, critical for the transformation of cords into perfusable vascular tubes. Studies in mouse, zebrafish, frog, and human endothelial cells have begun to outline the cellular and molecular requirements underlying lumen formation. Although the lumen can be generated through diverse mechanisms, the coordinated participation of multiple conserved molecules including transcription factors, small GTPases, and adhesion and polarity proteins remains a fundamental principle, leading us closer to a more thorough understanding of this complex event.
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Affiliation(s)
- Marta S Charpentier
- McAllister Heart Institute, Departments of Biology and Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
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21
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Shaik-Dasthagirisaheb YB, Varvara G, Murmura G, Saggini A, Potalivo G, Caraffa A, Antinolfi P, Tete' S, Tripodi D, Conti F, Cianchetti E, Toniato E, Rosati M, Conti P, Speranza L, Pantalone A, Saggini R, Theoharides TC, Pandolfi F. Vascular endothelial growth factor (VEGF), mast cells and inflammation. Int J Immunopathol Pharmacol 2013; 26:327-35. [PMID: 23755748 DOI: 10.1177/039463201302600206] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Vascular endothelial growth factor (VEGF) is one of the most important inducers of angiogenesis, therefore blocking angiogenesis has led to great promise in the treatment of various cancers and inflammatory diseases. VEGF, expressed in response to soluble mediators such as cytokines and growth factors, is important in the physiological development of blood vessels as well as development of vessels in tumors. In cancer patients VEGF levels are increased, and the expression of VEGF is associated with poor prognosis in diseases. VEGF is a mediator of angiogenesis and inflammation which are closely integrated processes in a number of physiological and pathological conditions including obesity, psoriasis, autoimmune diseases and tumor. Mast cells can be activated by anti-IgE to release potent mediators of inflammation and can also respond to bacterial or viral antigens, cytokines, growth factors and hormones, leading to differential release of distinct mediators without degranulation. Substance P strongly induces VEGF in mast cells, and IL-33 contributes to the stimulation and release of VEGF in human mast cells in a dose-dependent manner and acts synergistically in combination with Substance P. Here we report a strong link between VEGF and mast cells and we depict their role in inflammation and immunity.
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22
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HU XIAOPENG, YU JIE, ZHOU XIANG, LI ZHAOMING, XIA YUN, LUO ZHIYONG, WU YAQUN. A small GTPase-like protein fragment of Mycoplasma promotes tumor cell migration and proliferation in vitro via interaction with Rac1 and Stat3. Mol Med Rep 2013; 9:173-9. [DOI: 10.3892/mmr.2013.1766] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2013] [Accepted: 10/21/2013] [Indexed: 11/05/2022] Open
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23
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Ma J, Xue Y, Liu W, Yue C, Bi F, Xu J, Zhang J, Li Y, Zhong C, Chen Y. Role of activated Rac1/Cdc42 in mediating endothelial cell proliferation and tumor angiogenesis in breast cancer. PLoS One 2013; 8:e66275. [PMID: 23750283 PMCID: PMC3672132 DOI: 10.1371/journal.pone.0066275] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Accepted: 05/03/2013] [Indexed: 01/09/2023] Open
Abstract
Angiogenesis is a well-established target in anti-cancer therapy. Although vascular endothelial growth factor (VEGF)-mediated angiogenesis apparently requires the Rho GTPases Rac1 and Cdc42, the relevant mechanisms are unclear. Here, we determined that activated Rac1/Cdc42 in MCF-7 breast cancer cells could decrease p53 protein levels and increase VEGF secretion to promote proliferation and tube formation of human umbilical vein endothelial cells (HUVECs). However, these effects are reversed after ubiquitin-proteasome breakage. In exploring potential mechanisms for this relationship, we confirmed that activated Rac1/Cdc42 could enhance p53 protein ubiquitination and weaken p53 protein stability to increase VEGF expression. Furthermore, in a xenograft model using nude mice that stably express active Rac1/Cdc42 protein, active Rac1/Cdc42 decreased p53 levels and increased VEGF expression. Additionally, tumor angiogenesis was inhibited, and p53 protein levels were augmented, by intratumoral injection of the ubiquitin-proteasome inhibitor MG132. Finally in 339 human breast cancer tissues, our analyses indicated that Rac1/Cdc42 expression was related to advanced TNM staging, high proliferation index, ER status, and positive invasive features. In particular, our data suggests that high Rac1/Cdc42 expression is correlated with low wt-p53 and high VEGF expression. We conclude that activated Rac1/Cdc42 is a vascular regulator of tumor angiogenesis and that it may reduce stability of the p53 protein to promote VEGF expression by enhancing p53 protein ubiquitin.
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Affiliation(s)
- Ji Ma
- Department of Oncology, Xijing Hospital, The Fourth Military Medical University, Xi’an, Shannxi, China
- Department of Breast Surgery, Lanzhou General Hospital of People's Liberation Army, Lanzhou, Gansu, China
| | - Yan Xue
- Department of Oncology, Xijing Hospital, The Fourth Military Medical University, Xi’an, Shannxi, China
- * E-mail:
| | - Wenchao Liu
- Department of Oncology, Xijing Hospital, The Fourth Military Medical University, Xi’an, Shannxi, China
| | - Caixia Yue
- Laboratory of Signal Transduction and Molecular Targeted Therapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Feng Bi
- Laboratory of Signal Transduction and Molecular Targeted Therapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Junqing Xu
- Department of Radiology, Xijing Hospital, The Fourth Military Medical University, Xi’an, Shannxi, China
| | - Jian Zhang
- Department of Biochemistry and Molecular Biology, Fourth Military Medical University, Xi’an, Shannxi, China
| | - Yan Li
- Department of Biochemistry and Molecular Biology, Fourth Military Medical University, Xi’an, Shannxi, China
| | - Cuiping Zhong
- Department of Ear Nose Throat Surgery, Lanzhou General Hospital of People's Liberation Army, Lanzhou, Gansu, China
| | - Yan Chen
- Department of Oncology, Xijing Hospital, The Fourth Military Medical University, Xi’an, Shannxi, China
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Abstract
In this review we summarize the current understanding of signal transduction downstream of vascular endothelial growth factor A (VEGFA) and its receptor VEGFR2, and the relationship between these signal transduction pathways and the hallmark responses of VEGFA, angiogenesis and vascular permeability. These physiological responses involve a number of effectors, including extracellular signal-regulated kinases (ERKs), Src, phosphoinositide 3 kinase (PI3K)/Akt, focal adhesion kinase (FAK), Rho family GTPases, endothelial NO and p38 mitogen-activated protein kinase (MAPK). Several of these factors are involved in the regulation of both angiogenesis and vascular permeability. Tumour angiogenesis primarily relies on VEGFA-driven responses, which to a large extent result in a dysfunctional vasculature. The reason for this remains unclear, although it appears that certain aspects of the VEGFA-stimulated angiogenic milieu (high level of microvascular density and permeability) promote tumour expansion. The high degree of redundancy and complexity of VEGFA-driven tumour angiogenesis may explain why tumours commonly develop resistance to anti-angiogenic therapy targeting VEGFA signal transduction.
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Affiliation(s)
- L Claesson-Welsh
- Department of Immunology, Genetics and Pathology, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden.
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25
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Recent development in the effects of statins on cardiovascular disease through Rac1 and NADPH oxidase. Vascul Pharmacol 2013; 58:21-30. [DOI: 10.1016/j.vph.2012.10.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2012] [Revised: 10/05/2012] [Accepted: 10/08/2012] [Indexed: 01/05/2023]
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26
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Aman J, van Bezu J, Damanafshan A, Huveneers S, Eringa EC, Vogel SM, Groeneveld ABJ, Vonk Noordegraaf A, van Hinsbergh VWM, van Nieuw Amerongen GP. Effective treatment of edema and endothelial barrier dysfunction with imatinib. Circulation 2012; 126:2728-38. [PMID: 23099479 DOI: 10.1161/circulationaha.112.134304] [Citation(s) in RCA: 127] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Tissue edema and endothelial barrier dysfunction as observed in sepsis and acute lung injury carry high morbidity and mortality, but currently lack specific therapy. In a recent case report, we described fast resolution of pulmonary edema on treatment with the tyrosine kinase inhibitor imatinib through an unknown mechanism. Here, we explored the effect of imatinib on endothelial barrier dysfunction and edema formation. METHODS AND RESULTS We evaluated the effect of imatinib on endothelial barrier function in vitro and in vivo. In human macro- and microvascular endothelial monolayers, imatinib attenuated endothelial barrier dysfunction induced by thrombin and histamine. Small interfering RNA knock-downs of the imatinib-sensitive kinases revealed that imatinib attenuates endothelial barrier dysfunction via inhibition of Abl-related gene kinase (Arg/Abl2), a previously unknown mediator of endothelial barrier dysfunction. Indeed, Arg was activated by endothelial stimulation with thrombin, histamine, and vascular endothelial growth factor. Imatinib limited Arg-mediated endothelial barrier dysfunction by enhancing Rac1 activity and enforcing adhesion of endothelial cells to the extracellular matrix. Using mouse models of vascular leakage as proof-of-concept, we found that pretreatment with imatinib protected against vascular endothelial growth factor-induced vascular leakage in the skin, and effectively prevented edema formation in the lungs. In a murine model of sepsis, imatinib treatment (6 hours and 18 hours after induction of sepsis) attenuated vascular leakage in the kidneys and the lungs (24 hours after induction of sepsis). CONCLUSIONS Thus, imatinib prevents endothelial barrier dysfunction and edema formation via inhibition of Arg. These findings identify imatinib as a promising approach to permeability edema and indicate Arg as novel target for edema treatment.
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Affiliation(s)
- Jurjan Aman
- Department of Physiology, VU University Medical Center, Van der Boechorststraat 7, 1081 BT, Amsterdam, The Netherlands
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27
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Guillamet MCV, Rhee C, Patterson AJ. Cardiovascular management of septic shock in 2012. Curr Infect Dis Rep 2012; 14:493-502. [PMID: 22941043 DOI: 10.1007/s11908-012-0279-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Septic shock is a major cause of morbidity and mortality throughout the world. Source control, antimicrobial therapy, early goal-directed fluid resuscitation, and infusion of vasoactive pharmaceuticals remain the cornerstones of treatment. However, the cardiovascular management of septic shock is evolving. Basic science and clinical researchers have identified novel drug targets and are testing the efficacy of new therapeutic agents. For example, prevention of microvascular leak during septic shock is the focus of active investigations and may soon provide considerable benefit to patients. Among the important topics that will be discussed in this review are the following: the role of vascular endothelial dysfunction in microvascular leak, the impact of cytokines upon structural and functional proteins within the endothelial barrier and within the heart, and the ability of selective vasopressin 1a receptor agonists to minimize tissue edema and improve hemodynamic status.
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28
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Bryant PW, Zheng Q, Pumiglia KM. Focal adhesion kinase is a phospho-regulated repressor of Rac and proliferation in human endothelial cells. Biol Open 2012; 1:723-30. [PMID: 23213465 PMCID: PMC3507225 DOI: 10.1242/bio.20121008] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2012] [Accepted: 05/15/2012] [Indexed: 11/06/2022] Open
Abstract
Focal adhesion kinase (FAK) is critically positioned to integrate signals from the extracellular matrix and cellular adhesion. It is essential for normal vascular development and has been implicated in a wide range of cellular functions including the regulation of cell proliferation, migration, differentiation, and survival. It is currently being actively targeted therapeutically using different approaches. We have used human endothelial cells as a model system to compare the effects of inhibiting FAK through several different approaches including dominant negatives, kinase inhibitors and shRNA. We find that manipulations of FAK signaling that result in inhibition of FAK 397 phosphorylation inhibit proliferation and migration. However, abolition of FAK expression using stable (shRNA) or transient (siRNA) approaches does not interfere with these cellular functions. The ability to regulate cell proliferation by FAK manipulation is correlated with the activation status of Rac, an essential signal for the regulation of cyclin-dependent kinase inhibitors. The knockdown of FAK, while not affecting cellular proliferation or migration, dramatically interferes with vascular morphogenesis and survival, mirroring in vivo findings. We propose a novel model of FAK signaling whereby one of the multifunctional roles of FAK as a signaling protein includes FAK as a phospho-regulated repressor of Rac activation, with important implications on interpretation of research experiments and therapeutic development.
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Affiliation(s)
- Patrick W Bryant
- Cell Biology and Cancer Research, Albany Medical College , Albany, NY 12208 , USA
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29
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Junctional protein regulation by sphingosine kinase 2 contributes to blood-brain barrier protection in hypoxic preconditioning-induced cerebral ischemic tolerance. J Cereb Blood Flow Metab 2012; 32:1014-23. [PMID: 22314269 PMCID: PMC3367228 DOI: 10.1038/jcbfm.2012.3] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Protection of the blood-brain barrier (BBB) is correlated with improved outcome in stroke. Sphingosine kinase (SphK)-directed production of sphingosine-1-phosphate, which we previously documented as being vital to preconditioning-induced stroke protection, mediates peripheral vascular integrity via junctional protein regulation. We used a hypoxic preconditioning (HPC) model in adult wild-type and SphK2-null mice to examine the isoform-specific role of SphK2 signaling for ischemic tolerance to transient middle cerebral artery occlusion and attendant BBB protection. Reductions in infarct volume and BBB permeability in HPC-treated mice were completely lost in SphK2-null mice. Hypoxic preconditioning-induced attenuation of postischemic BBB disruption in wild types, evidenced by reduced extravascular immunoglobulin G intensity, suggests direct protection of BBB integrity. Measurement of BBB junctional protein status in response to HPC revealed SphK2-dependent increases in triton-insoluble claudin-5 and VE-cadherin, which may serve to strengthen the BBB before stroke. Postischemic loss of VE-cadherin, occludin, and zona occludens-1 in SphK2-null mice with prior HPC suggests that SphK2-dependent protection of these adherens and tight junction proteins is compulsory for HPC to establish a vasculoprotective phenotype. Further elucidation of the mediators of this endogenous, HPC-activated lipid signaling pathway, and their role in protecting the ischemic BBB, may provide new therapeutic targets for cerebrovascular protection in stroke patients.
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30
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David S, Ghosh CC, Mukherjee A, Parikh SM. Angiopoietin-1 requires IQ domain GTPase-activating protein 1 to activate Rac1 and promote endothelial barrier defense. Arterioscler Thromb Vasc Biol 2012; 31:2643-52. [PMID: 21885850 DOI: 10.1161/atvbaha.111.233189] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
OBJECTIVE IQ domain GTPase-activating protein 1 (IQGAP1) contributes to cytoskeletal network regulation in epithelial cells by its scaffolding properties and by binding the Rho GTPase Rac1 to maintain its activity. The functions of IQGAP1 in endothelial cells beyond angiogenesis remain unclear. We hypothesized that IQGAP1 participates in the regulation of endothelial barrier function. METHODS AND RESULTS Silencing IQGAP1 in human microvascular endothelial cells resulted in a disruption of adherens junctions, formation of interendothelial gaps, and a reduction in barrier function. Furthermore, silencing of IQGAP1 abrogated the barrier enhancement effect of angiopoietin-1 (Angpt-1) and abolished the barrier-stabilizing effect of Angpt-1 on thrombin-stimulated cells. Coimmunoprecipitation detected binding of endogenous IQGAP1 with Rac1 at baseline that was stronger when Rac1 was activated and weaker when it was deactivated. Measurement of GTP-bound Rac1 revealed that Angpt-1 failed to activate Rac1 not only if IQGAP1 was silenced but also if cells were transfected with a mutant disabled in Rac1 binding (T1050AX2). Furthermore, a dominant-active Rac1 was sufficient to completely reverse the morphological and functional changes induced by reduction in IQGAP1. CONCLUSION These experiments are the first demonstration of IQGAP1 regulating barrier function in any cell type. Further, our data show that Angpt-1 requires IQGAP1 as an indispensable activator of Rac1.
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Affiliation(s)
- Sascha David
- Center for Vascular Biology Research, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA
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31
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Sacharidou A, Stratman AN, Davis GE. Molecular mechanisms controlling vascular lumen formation in three-dimensional extracellular matrices. Cells Tissues Organs 2011; 195:122-43. [PMID: 21997121 DOI: 10.1159/000331410] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Considerable progress has been made toward a molecular understanding of how cells form lumen and tube structures in three-dimensional (3D) extracellular matrices (ECM). This progress has occurred through work performed with endothelial and epithelial cell models using both in vitro and in vivo approaches. Despite the apparent similarities between endothelial and epithelial cell lumen and tube formation mechanisms, there are clear distinctions that directly relate to their functional differences. This review will focus on endothelial cell (EC) lumen formation mechanisms which control blood vessel formation during development and postnatal life. Of great interest is that an EC lumen signaling complex has been identified which controls human EC lumen and tube formation in 3D matrices and which coordinates integrin-ECM contacts, cell surface proteolysis, cytoskeletal rearrangements, and cell polarity. This complex consists of the collagen-binding integrin α2β1, the collagen-degrading membrane-type 1 matrix metalloproteinase (MT1-MMP), junction adhesion molecule (Jam)C, JamB, polarity proteins Par3 and Par6b, and the Rho GTPase Cdc42-GTP. These interacting proteins are necessary to stimulate 3D matrix-specific signaling events (including activation of protein kinase cascades that regulate the actin and microtubule cytoskeletons) to control the formation of EC lumens and tube networks. Also, EC lumen formation is directly coupled to the generation of vascular guidance tunnels, enzymatically generated ECM conduits that facilitate EC tube remodeling and maturation. Mural cells such as pericytes are recruited along EC tubes within these tunnel spaces to control ECM remodeling events resulting in vascular basement membrane matrix assembly, a key step in tube maturation and stabilization.
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Affiliation(s)
- Anastasia Sacharidou
- Department of Medical Pharmacology and Physiology, University of Missouri School of Medicine, Dalton Cardiovascular Research Center, Columbia, Mo. 65212, USA
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32
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van der Heijden M, van Nieuw Amerongen GP, van Bezu J, Paul MA, Groeneveld ABJ, van Hinsbergh VWM. Opposing effects of the angiopoietins on the thrombin-induced permeability of human pulmonary microvascular endothelial cells. PLoS One 2011; 6:e23448. [PMID: 21858121 PMCID: PMC3156229 DOI: 10.1371/journal.pone.0023448] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Accepted: 07/18/2011] [Indexed: 01/25/2023] Open
Abstract
Background Angiopoietin-2 (Ang-2) is associated with lung injury in ALI/ARDS. As endothelial activation by thrombin plays a role in the permeability of acute lung injury and Ang-2 may modulate the kinetics of thrombin-induced permeability by impairing the organization of vascular endothelial (VE-)cadherin, and affecting small Rho GTPases in human pulmonary microvascular endothelial cells (HPMVECs), we hypothesized that Ang-2 acts as a sensitizer of thrombin-induced hyperpermeability of HPMVECs, opposed by Ang-1. Methodology/Principal Findings Permeability was assessed by measuring macromolecule passage and transendothelial electrical resistance (TEER). Angiopoietins did not affect basal permeability. Nevertheless, they had opposing effects on the thrombin-induced permeability, in particular in the initial phase. Ang-2 enhanced the initial permeability increase (passage, P = 0.010; TEER, P = 0.021) in parallel with impairment of VE-cadherin organization without affecting VE-cadherin Tyr685 phosphorylation or increasing RhoA activity. Ang-2 also increased intercellular gap formation. Ang-1 preincubation increased Rac1 activity, enforced the VE-cadherin organization, reduced the initial thrombin-induced permeability (TEER, P = 0.027), while Rac1 activity simultaneously normalized, and reduced RhoA activity at 15 min thrombin exposure (P = 0.039), but not at earlier time points. The simultaneous presence of Ang-2 largely prevented the effect of Ang-1 on TEER and macromolecule passage. Conclusions/Significance Ang-1 attenuated thrombin-induced permeability, which involved initial Rac1 activation-enforced cell-cell junctions, and later RhoA inhibition. In addition to antagonizing Ang-1, Ang-2 had also a direct effect itself. Ang-2 sensitized the initial thrombin-induced permeability accompanied by destabilization of VE-cadherin junctions and increased gap formation, in the absence of increased RhoA activity.
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Affiliation(s)
- Melanie van der Heijden
- Department of Intensive Care, Institute for Cardiovascular Research, VU University Medical Centre, Amsterdam, The Netherlands
- Department of Physiology, Institute for Cardiovascular Research, VU University Medical Centre, Amsterdam, The Netherlands
| | - Geerten P. van Nieuw Amerongen
- Department of Physiology, Institute for Cardiovascular Research, VU University Medical Centre, Amsterdam, The Netherlands
- * E-mail:
| | - Jan van Bezu
- Department of Physiology, Institute for Cardiovascular Research, VU University Medical Centre, Amsterdam, The Netherlands
| | - Marinus A. Paul
- Department of Cardiothoracic Surgery, VU University Medical Centre, Amsterdam, The Netherlands
| | - A. B. Johan Groeneveld
- Department of Intensive Care, Institute for Cardiovascular Research, VU University Medical Centre, Amsterdam, The Netherlands
| | - Victor W. M. van Hinsbergh
- Department of Physiology, Institute for Cardiovascular Research, VU University Medical Centre, Amsterdam, The Netherlands
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ANGPTL4 modulates vascular junction integrity by integrin signaling and disruption of intercellular VE-cadherin and claudin-5 clusters. Blood 2011; 118:3990-4002. [PMID: 21841165 DOI: 10.1182/blood-2011-01-328716] [Citation(s) in RCA: 179] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Vascular disruption induced by interactions between tumor-secreted permeability factors and adhesive proteins on endothelial cells facilitates metastasis. The role of tumor-secreted C-terminal fibrinogen-like domain of angiopoietin-like 4 (cANGPTL4) in vascular leakiness and metastasis is controversial because of the lack of understanding of how cANGPTL4 modulates vascular integrity. Here, we show that cANGPTL4 instigated the disruption of endothelial continuity by directly interacting with 3 novel binding partners, integrin α5β1, VE-cadherin, and claudin-5, in a temporally sequential manner, thus facilitating metastasis. We showed that cANGPTL4 binds and activates integrin α5β1-mediated Rac1/PAK signaling to weaken cell-cell contacts. cANGPTL4 subsequently associated with and declustered VE-cadherin and claudin-5, leading to endothelial disruption. Interfering with the formation of these cANGPTL4 complexes delayed vascular disruption. In vivo vascular permeability and metastatic assays performed using ANGPTL4-knockout and wild-type mice injected with either control or ANGPTL4-knockdown tumors confirmed that cANGPTL4 induced vascular leakiness and facilitated lung metastasis in mice. Thus, our findings elucidate how cANGPTL4 induces endothelial disruption. Our findings have direct implications for targeting cANGPTL4 to treat cancer and other vascular pathologies.
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34
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Examining the role of Rac1 in tumor angiogenesis and growth: a clinically relevant RNAi-mediated approach. Angiogenesis 2011; 14:457-66. [PMID: 21789714 DOI: 10.1007/s10456-011-9229-x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2011] [Accepted: 07/15/2011] [Indexed: 12/30/2022]
Abstract
Angiogenesis, the sprouting of new blood vessels from the pre-existing vasculature, is a well established target in anti-cancer therapy. It is thought that the Rho GTPase Rac1 is required during vascular endothelial growth factor (VEGF)-mediated angiogenesis. In the present study, we have used a clinically relevant RNA interference approach to silence Rac1 expression. Human umbilical vein endothelial cells were transiently transfected with non-specific control siRNA (siNS) or Rac1 siRNA (siRac1) using electroporation or Lipofectamine 2000. Functional assays with transfected endothelial cells were performed to determine the effect of Rac1 knockdown on angiogenesis in vitro. Silencing of Rac1 inhibited VEGF-mediated tube formation, cell migration, invasion and proliferation. In addition, treatment with Rac1 siRNA inhibited angiogenesis in an in vivo Matrigel plug assay. Intratumoral injections of siRac1 almost completely inhibited the growth of grafted Neuro2a tumors and reduced tumor angiogenesis. Together, these data indicate that Rac1 is an important regulator of VEGF-mediated angiogenesis. Knockdown of Rac1 may represent an attractive approach to inhibit tumor angiogenesis and growth.
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Goldenberg NM, Steinberg BE, Slutsky AS, Lee WL. Broken Barriers: A New Take on Sepsis Pathogenesis. Sci Transl Med 2011; 3:88ps25. [DOI: 10.1126/scitranslmed.3002011] [Citation(s) in RCA: 227] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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36
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Abstract
Vascular endothelial growth factor (VEGF) is a major driver of physiologic and pathologic vascularization, but VEGF therapies generally fail to sustainably revascularize ischemic tissues. In this issue of Blood, Hoang and coworkers demonstrate that Rac1 may be the missing ingredient for achieving this goal.
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37
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Bayless KJ, Johnson GA. Role of the cytoskeleton in formation and maintenance of angiogenic sprouts. J Vasc Res 2011; 48:369-85. [PMID: 21464572 DOI: 10.1159/000324751] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2010] [Accepted: 01/10/2011] [Indexed: 12/19/2022] Open
Abstract
Angiogenesis is the formation of new blood vessels from pre-existing structures, and is a key step in tissue and organ development, wound healing and pathological events. Changes in cell shape orchestrated by the cytoskeleton are integral to accomplishing the various steps of angiogenesis, and an intact cytoskeleton is also critical for maintaining newly formed structures. This review focuses on how the 3 main cytoskeletal elements--microfilaments, microtubules, and intermediate filaments--regulate the formation and maintenance of angiogenic sprouts. Multiple classes of compounds target microtubules and microfilaments, revealing much about the role of actin and tubulin and their associated molecules in angiogenic sprout formation and maintenance. In contrast, intermediate filaments are much less studied, yet intriguing evidence suggests a vital, but unresolved, role in angiogenic sprouting. This review discusses evidence for regulatory molecules and pharmacological compounds that affect actin, microtubule and intermediate filament dynamics to alter various steps of angiogenesis, including endothelial sprout formation and maintenance.
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Affiliation(s)
- Kayla J Bayless
- Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, TX 77843-1114, USA.
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38
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Davis GE, Stratman AN, Sacharidou A, Koh W. Molecular basis for endothelial lumen formation and tubulogenesis during vasculogenesis and angiogenic sprouting. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2011; 288:101-65. [PMID: 21482411 DOI: 10.1016/b978-0-12-386041-5.00003-0] [Citation(s) in RCA: 132] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Many studies reveal a fundamental role for extracellular matrix-mediated signaling through integrins and Rho GTPases as well as matrix metalloproteinases (MMPs) in the molecular control of vascular tube morphogenesis in three-dimensional (3D) tissue environments. Recent work has defined an endothelial cell (EC) lumen signaling complex of proteins that controls these vascular morphogenic events. These findings reveal a signaling interdependence between Cdc42 and MT1-MMP to control the 3D matrix-specific process of EC tubulogenesis. The EC tube formation process results in the creation of a network of proteolytically generated vascular guidance tunnels in 3D matrices that are utilized to remodel EC-lined tubes through EC motility and could facilitate processes such as flow-induced remodeling and arteriovenous EC sorting and differentiation. Within vascular guidance tunnels, key dynamic interactions occur between ECs and pericytes to affect vessel remodeling, diameter, and vascular basement membrane matrix assembly, a fundamental process necessary for endothelial tube maturation and stabilization. Thus, the EC lumen and tube formation mechanism coordinates the concomitant establishment of a network of vascular tubes within tunnel spaces to allow for flow responsiveness, EC-mural cell interactions, and vascular extracellular matrix assembly to control the development of the functional microcirculation.
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Affiliation(s)
- George E Davis
- Department of Medical Pharmacology and Physiology, University of Missouri School of Medicine, Columbia, Missouri, USA
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