101
|
Raimondi C, Brash JT, Fantin A, Ruhrberg C. NRP1 function and targeting in neurovascular development and eye disease. Prog Retin Eye Res 2016; 52:64-83. [PMID: 26923176 PMCID: PMC4854174 DOI: 10.1016/j.preteyeres.2016.02.003] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 02/08/2016] [Accepted: 02/10/2016] [Indexed: 12/19/2022]
Abstract
Neuropilin 1 (NRP1) is expressed by neurons, blood vessels, immune cells and many other cell types in the mammalian body and binds a range of structurally and functionally diverse extracellular ligands to modulate organ development and function. In recent years, several types of mouse knockout models have been developed that have provided useful tools for experimental investigation of NRP1 function, and a multitude of therapeutics targeting NRP1 have been designed, mostly with the view to explore them for cancer treatment. This review provides a general overview of current knowledge of the signalling pathways that are modulated by NRP1, with particular focus on neuronal and vascular roles in the brain and retina. This review will also discuss the potential of NRP1 inhibitors for the treatment for neovascular eye diseases.
Collapse
Affiliation(s)
- Claudio Raimondi
- UCL Institute of Ophthalmology, University College London, 11-43 Bath Street, London EC1V 9EL, UK
| | - James T Brash
- UCL Institute of Ophthalmology, University College London, 11-43 Bath Street, London EC1V 9EL, UK
| | - Alessandro Fantin
- UCL Institute of Ophthalmology, University College London, 11-43 Bath Street, London EC1V 9EL, UK
| | - Christiana Ruhrberg
- UCL Institute of Ophthalmology, University College London, 11-43 Bath Street, London EC1V 9EL, UK.
| |
Collapse
|
102
|
Baek JI, Kwon SH, Zuo X, Choi SY, Kim SH, Lipschutz JH. Dynamin Binding Protein (Tuba) Deficiency Inhibits Ciliogenesis and Nephrogenesis in Vitro and in Vivo. J Biol Chem 2016; 291:8632-43. [PMID: 26895965 DOI: 10.1074/jbc.m115.688663] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Indexed: 12/31/2022] Open
Abstract
Dysfunction of renal primary cilia leads to polycystic kidney disease. We previously showed that the exocyst, a protein trafficking complex, is essential for ciliogenesis and regulated by multiple Rho and Rab family GTPases, such as Cdc42. Cdc42 deficiency resulted in a disruption of renal ciliogenesis and a polycystic kidney disease phenotype in zebrafish and mice. Here we investigate the role of Dynamin binding protein (also known as Tuba), a Cdc42-specific guanine nucleotide exchange factor, in ciliogenesis and nephrogenesis using Tuba knockdown Madin-Darby canine kidney cells and tuba knockdown in zebrafish. Tuba depletion resulted in an absence of cilia, with impaired apical polarization and inhibition of hepatocyte growth factor-induced tubulogenesis in Tuba knockdown Madin-Darby canine kidney cell cysts cultured in a collagen gel. In zebrafish, tuba was expressed in multiple ciliated organs, and, accordingly, tuba start and splice site morphants showed various ciliary mutant phenotypes in these organs. Co-injection of tuba and cdc42 morpholinos at low doses, which alone had no effect, resulted in genetic synergy and led to abnormal kidney development with highly disorganized pronephric duct cilia. Morpholinos targeting two other guanine nucleotide exchange factors not known to be in the Cdc42/ciliogenesis pathway and a scrambled control morpholino showed no phenotypic effect. Given the molecular nature of Cdc42 and Tuba, our data strongly suggest that tuba and cdc42 act in the same ciliogenesis pathway. Our study demonstrates that Tuba deficiency causes an abnormal renal ciliary and morphogenetic phenotype. Tuba most likely plays a critical role in ciliogenesis and nephrogenesis by regulating Cdc42 activity.
Collapse
Affiliation(s)
- Jeong-In Baek
- From the Department of Medicine, Medical University of South Carolina, Charleston, South Carolina 29425 and
| | - Sang-Ho Kwon
- From the Department of Medicine, Medical University of South Carolina, Charleston, South Carolina 29425 and
| | - Xiaofeng Zuo
- From the Department of Medicine, Medical University of South Carolina, Charleston, South Carolina 29425 and
| | - Soo Young Choi
- From the Department of Medicine, Medical University of South Carolina, Charleston, South Carolina 29425 and
| | - Seok-Hyung Kim
- From the Department of Medicine, Medical University of South Carolina, Charleston, South Carolina 29425 and
| | - Joshua H Lipschutz
- From the Department of Medicine, Medical University of South Carolina, Charleston, South Carolina 29425 and the Department of Medicine, Ralph H. Johnson Veterans Affairs Medical Center, Charleston, South Carolina 29401
| |
Collapse
|
103
|
Agarwal AK, Tunison K, Dalal JS, Yen CLE, Farese RV, Horton JD, Garg A. Mogat1 deletion does not ameliorate hepatic steatosis in lipodystrophic (Agpat2-/-) or obese (ob/ob) mice. J Lipid Res 2016; 57:616-30. [PMID: 26880786 DOI: 10.1194/jlr.m065896] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Indexed: 12/31/2022] Open
Abstract
Reducing triacylglycerol (TAG) in the liver continues to pose a challenge in states of nonalcoholic hepatic steatosis. MonoacylglycerolO-acyltransferase (MOGAT) enzymes convert monoacylglycerol (MAG) to diacylglycerol, a precursor for TAG synthesis, and are involved in a major pathway of TAG synthesis in selected tissues, such as small intestine. MOGAT1 possesses MGAT activity in in vitro assays, but its physiological function in TAG metabolism is unknown. Recent studies suggest a role for MOGAT1 in hepatic steatosis in lipodystrophic [1-acylglycerol-3-phosphateO-acyltransferase (Agpat)2(-/-)] and obese (ob/ob) mice. To test this, we deletedMogat1in theAgpat2(-/-)andob/obgenetic background to generateMogat1(-/-);Agpat2(-/-)andMogat1(-/-);ob/obdouble knockout (DKO) mice. Here we report that, despite the absence ofMogat1in either DKO mouse model, we did not find any decrease in liver TAG by 16 weeks of age. Additionally, there were no measureable changes in plasma glucose (diabetes) and insulin resistance. Our data indicate a minimal role, if any, of MOGAT1 in liver TAG synthesis, and that TAG synthesis in steatosis associated with lipodystrophy and obesity is independent of MOGAT1. Our findings suggest that MOGAT1 likely has an alternative function in vivo.
Collapse
Affiliation(s)
- Anil K Agarwal
- Division of Nutrition and Metabolic Diseases, Center for Human Nutrition, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Katie Tunison
- Division of Nutrition and Metabolic Diseases, Center for Human Nutrition, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Jasbir S Dalal
- Division of Nutrition and Metabolic Diseases, Center for Human Nutrition, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Chi-Liang Eric Yen
- Gladstone Institute of Cardiovascular Disease San Francisco, San Francisco, CA 94158
| | - Robert V Farese
- Gladstone Institute of Cardiovascular Disease San Francisco, San Francisco, CA 94158
| | - Jay D Horton
- Division of Nutrition and Metabolic Diseases, Center for Human Nutrition, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390 Division of Gastroenterology and Departments of Molecular Genetics and Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Abhimanyu Garg
- Division of Nutrition and Metabolic Diseases, Center for Human Nutrition, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390
| |
Collapse
|
104
|
Unique and Overlapping Functions of Formins Frl and DAAM During Ommatidial Rotation and Neuronal Development in Drosophila. Genetics 2016; 202:1135-51. [PMID: 26801180 DOI: 10.1534/genetics.115.181438] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 01/18/2016] [Indexed: 01/14/2023] Open
Abstract
The noncanonical Frizzled/planar cell polarity (PCP) pathway regulates establishment of polarity within the plane of an epithelium to generate diversity of cell fates, asymmetric, but highly aligned structures, or to orchestrate the directional migration of cells during convergent extension during vertebrate gastrulation. In Drosophila, PCP signaling is essential to orient actin wing hairs and to align ommatidia in the eye, in part by coordinating the movement of groups of photoreceptor cells during ommatidial rotation. Importantly, the coordination of PCP signaling with changes in the cytoskeleton is essential for proper epithelial polarity. Formins polymerize linear actin filaments and are key regulators of the actin cytoskeleton. Here, we show that the diaphanous-related formin, Frl, the single fly member of the FMNL (formin related in leukocytes/formin-like) formin subfamily affects ommatidial rotation in the Drosophila eye and is controlled by the Rho family GTPase Cdc42. Interestingly, we also found that frl mutants exhibit an axon growth phenotype in the mushroom body, a center for olfactory learning in the Drosophila brain, which is also affected in a subset of PCP genes. Significantly, Frl cooperates with Cdc42 and another formin, DAAM, during mushroom body formation. This study thus suggests that different formins can cooperate or act independently in distinct tissues, likely integrating various signaling inputs with the regulation of the cytoskeleton. It furthermore highlights the importance and complexity of formin-dependent cytoskeletal regulation in multiple organs and developmental contexts.
Collapse
|
105
|
Steffen A, Stradal TEB, Rottner K. Signalling Pathways Controlling Cellular Actin Organization. Handb Exp Pharmacol 2016; 235:153-178. [PMID: 27757765 DOI: 10.1007/164_2016_35] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The actin cytoskeleton is essential for morphogenesis and virtually all types of cell shape changes. Reorganization is per definition driven by continuous disassembly and re-assembly of actin filaments, controlled by major, ubiquitously operating machines. These are specifically employed by the cell to tune its activities in accordance with respective environmental conditions or to satisfy specific needs.Here we sketch some fundamental signalling pathways established to contribute to the reorganization of specific actin structures at the plasma membrane. Rho-family GTPases are at the core of these pathways, and dissection of their precise contributions to actin reorganization in different cell types and tissues will thus continue to improve our understanding of these important signalling nodes. Furthermore, we will draw your attention to the emerging theme of actin reorganization on intracellular membranes, its functional relation to Rho-GTPase signalling, and its relevance for the exciting phenomenon autophagy.
Collapse
Affiliation(s)
- Anika Steffen
- Department of Cell Biology, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124, Braunschweig, Germany
| | - Theresia E B Stradal
- Department of Cell Biology, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124, Braunschweig, Germany.
| | - Klemens Rottner
- Department of Cell Biology, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124, Braunschweig, Germany.,Zoological Institute, Technische Universität Braunschweig, Spielmannstrasse 7, 38106, Braunschweig, Germany
| |
Collapse
|
106
|
Jung H, Isogai S, Kamei M, Castranova D, Gore A, Weinstein B. Imaging blood vessels and lymphatic vessels in the zebrafish. Methods Cell Biol 2016; 133:69-103. [DOI: 10.1016/bs.mcb.2016.03.023] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
|
107
|
Formins at the Junction. Trends Biochem Sci 2015; 41:148-159. [PMID: 26732401 DOI: 10.1016/j.tibs.2015.12.002] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Revised: 12/01/2015] [Accepted: 12/04/2015] [Indexed: 12/21/2022]
Abstract
The actin cytoskeleton and adhesion junctions are physically and functionally coupled at the cell-cell interface between epithelial cells. The actin regulatory complex Arp2/3 has an established role in the turnover of junctional actin; however, the role of formins, the largest group of actin regulators, is less clear. Formins dynamically shape the actin cytoskeleton and have various functions within cells. In this review we describe recent progress on how formins regulate actin dynamics at cell-cell contacts and highlight formin functions during polarized protein traffic necessary for epithelialization.
Collapse
|
108
|
Li J, Yue Y, Zhao Q. Retinoic Acid Signaling Is Essential for Valvulogenesis by Affecting Endocardial Cushions Formation in Zebrafish Embryos. Zebrafish 2015; 13:9-18. [PMID: 26671342 DOI: 10.1089/zeb.2015.1117] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Retinoic acid (RA) plays important roles in many stages of heart morphogenesis. Zebrafish embryos treated with exogenous RA display defective atrio-ventricular canal (AVC) specification. However, whether endogenous RA signaling takes part in cardiac valve formation remains unknown. Herein, we investigated the role of RA signaling in cardiac valve development by knocking down aldh1a2, the gene encoding an enzyme that is mainly responsible for RA synthesis during early development, in zebrafish embryos. The results showed that partially knocking down aldh1a2 caused defective formation of primitive cardiac valve leaflets at 108 hpf (hour post-fertilization). Inhibiting endogenous RA signaling by 4-diethylaminobenzal-dehyde revealed that 16-26 hpf was a key time window when RA signaling affects the valvulogenesis. The aldh1a2 morphants had defective formation of endocardial cushion (EC) at 76 hpf though they had almost normal hemodynamics and cardiac chamber specification at early development. Examining the expression patterns of AVC marker genes including bmp4, bmp2b, nppa, notch1b, and has2, we found the morphants displayed abnormal development of endocardial AVC but almost normal development of myocardial AVC at 50 hpf. Being consistent with the reduced expression of notch1b in endocardial AVC, the VE-cadherin gene cdh5, the downstream gene of Notch signaling, was ectopically expressed in AVC of aldh1a2 morphants at 50 hpf, and overexpression of cdh5 greatly affected the formation of EC in the embryos at 76 hpf. Taken together, our results suggest that RA signaling plays essential roles in zebrafish cardiac valvulogenesis.
Collapse
Affiliation(s)
- Junbo Li
- MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing University , Nanjing, China
| | - Yunyun Yue
- MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing University , Nanjing, China
| | - Qingshun Zhao
- MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing University , Nanjing, China
| |
Collapse
|
109
|
García de Vinuesa A, Abdelilah-Seyfried S, Knaus P, Zwijsen A, Bailly S. BMP signaling in vascular biology and dysfunction. Cytokine Growth Factor Rev 2015; 27:65-79. [PMID: 26823333 DOI: 10.1016/j.cytogfr.2015.12.005] [Citation(s) in RCA: 118] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The vascular system is critical for developmental growth, tissue homeostasis and repair but also for tumor development. Bone morphogenetic protein (BMP) signaling has recently emerged as a fundamental pathway of the endothelium by regulating cardiovascular and lymphatic development and by being causative for several vascular dysfunctions. Two vascular disorders have been directly linked to impaired BMP signaling: pulmonary arterial hypertension and hereditary hemorrhagic telangiectasia. Endothelial BMP signaling critically depends on the cellular context, which includes among others vascular heterogeneity, exposure to flow, and the intertwining with other signaling cascades (Notch, WNT, Hippo and hypoxia). The purpose of this review is to highlight the most recent findings illustrating the clear need for reconsidering the role of BMPs in vascular biology.
Collapse
Affiliation(s)
- Amaya García de Vinuesa
- Department of Molecular Cell Biology, Cancer Genomics Centre Netherlands, Leiden University Medical Center, Leiden, The Netherlands
| | - Salim Abdelilah-Seyfried
- Institute of Biochemistry and Biology, Potsdam University, Karl-Liebknecht-Straße 24-25, D-14476 Potsdam, Germany; Institute of Molecular Biology, Hannover Medical School, Carl-Neuberg Straße 1, D-30625 Hannover, Germany
| | - Petra Knaus
- Institute for Chemistry and Biochemistry, Freie Universitaet Berlin, Berlin, Germany
| | - An Zwijsen
- VIB Center for the Biology of Disease, Leuven, Belgium; KU Leuven, Department of Human Genetics, Leuven, Belgium
| | - Sabine Bailly
- Institut National de la Santé et de la Recherche Médicale (INSERM, U1036), Grenoble F-38000, France; Commissariat à l'Énergie Atomique et aux Energies Alternatives, Institut de Recherches en Technologies et Sciences pour le Vivant, Laboratoire Biologie du Cancer et de l'Infection, Grenoble F-38000, France; Université Grenoble-Alpes, Grenoble F-38000, France.
| |
Collapse
|
110
|
Ye L, Jiang WG. Bone morphogenetic proteins in tumour associated angiogenesis and implication in cancer therapies. Cancer Lett 2015; 380:586-597. [PMID: 26639195 DOI: 10.1016/j.canlet.2015.10.036] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Revised: 09/17/2015] [Accepted: 10/12/2015] [Indexed: 02/09/2023]
Abstract
Bone morphogenetic protein (BMP) belongs to transforming growth factor-β superfamily. To date, more than 20 BMPs have been identified in humans. BMPs play a critical role in embryonic and postnatal development, and also in maintaining homeostasis in different organs and tissues by regulating cell differentiation, proliferation, survival and motility. They play important roles in the development and progression of certain malignancies, including prostate cancer, breast cancer, lung cancer, etc. Recently, more evidence shows that BMPs are also involved in tumour associated angiogenesis. For example BMP can either directly regulate the functions of vascular endothelial cells or indirectly influence the angiogenesis via regulation of angiogenic factors, such as vascular endothelial growth factor (VEGF). Such crosstalk can also be reflected in the interaction with other angiogenic factors, like hepatocyte growth factor (HGF) and basic fibroblast growth factor (bFGF). All these factors are involved in the orchestration of the angiogenic process during tumour development and progression. Review of the relevant studies will provide a comprehensive prospective on current understanding and shed light on the corresponding therapeutic opportunity.
Collapse
Affiliation(s)
- Lin Ye
- Metastasis & Angiogenesis Research Group, Cardiff University-Peking University Cancer Institute, Institute of Cancer and Genetics, Cardiff University School of Medicine, Cardiff CF14 4XN, UK.
| | - Wen G Jiang
- Metastasis & Angiogenesis Research Group, Cardiff University-Peking University Cancer Institute, Institute of Cancer and Genetics, Cardiff University School of Medicine, Cardiff CF14 4XN, UK
| |
Collapse
|
111
|
Yokota Y, Nakajima H, Wakayama Y, Muto A, Kawakami K, Fukuhara S, Mochizuki N. Endothelial Ca 2+ oscillations reflect VEGFR signaling-regulated angiogenic capacity in vivo. eLife 2015; 4. [PMID: 26588168 PMCID: PMC4720519 DOI: 10.7554/elife.08817] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Accepted: 11/19/2015] [Indexed: 11/26/2022] Open
Abstract
Sprouting angiogenesis is a well-coordinated process controlled by multiple extracellular inputs, including vascular endothelial growth factor (VEGF). However, little is known about when and how individual endothelial cell (EC) responds to angiogenic inputs in vivo. Here, we visualized endothelial Ca2+ dynamics in zebrafish and found that intracellular Ca2+ oscillations occurred in ECs exhibiting angiogenic behavior. Ca2+ oscillations depended upon VEGF receptor-2 (Vegfr2) and Vegfr3 in ECs budding from the dorsal aorta (DA) and posterior cardinal vein, respectively. Thus, visualizing Ca2+ oscillations allowed us to monitor EC responses to angiogenic cues. Vegfr-dependent Ca2+ oscillations occurred in migrating tip cells as well as stalk cells budding from the DA. We investigated how Dll4/Notch signaling regulates endothelial Ca2+ oscillations and found that it was required for the selection of single stalk cell as well as tip cell. Thus, we captured spatio-temporal Ca2+ dynamics during sprouting angiogenesis, as a result of cellular responses to angiogenic inputs. DOI:http://dx.doi.org/10.7554/eLife.08817.001 Throughout life, new blood vessels grow out like branches from existing vessels in a process called “sprouting angiogenesis”. This involves some of the endothelial cells that line the inner surface of the blood vessel migrating outwards, creating a vessel sprout made up of tip cells and stalk cells. Sprouting is controlled by two opposing signaling systems. One pathway is triggered by a molecule called vascular endothelial growth factor (VEGF). This molecule binds to receptor proteins to activate a range of signaling processes that stimulate endothelial cells to become tip cells, and so encourage the formation of new sprouts. However, it was not known exactly when or how the endothelial cells respond to these signals. By contrast, the Notch signaling pathway inhibits sprouting angiogenesis. The two signaling pathways interact with each other: VEGF signaling in tip cells activates Notch signaling in neighboring cells, which then prevents VEGF signaling in these cells. This feedback mechanism helps a new sprout to form by suppressing tip-like activity in the cells surrounding a new tip cell, forcing these cells to become stalk cells. Activating VEGF receptors also causes brief increases, or oscillations, in the level of calcium ions inside the endothelial cells. Now, Yokota, Nakajima et al. have investigated VEGF activity by genetically engineering zebrafish embryos so that fluorescent proteins inside their endothelial cells emit more light when calcium ion levels inside the cell increase. As zebrafish embryos are transparent, this change in fluorescence can be seen in the living animal. Imaging the embryos revealed that calcium ion oscillations occur in both tip and stalk cells in response to VEGF signaling as they bud from vessels. Notch signaling can also regulate the calcium ion oscillations; this controls whether an individual cell becomes a tip or a stalk cell, and restricts the number of stalk cells in the sprout. The flow of blood through the vessels is also thought to influence calcium ion oscillations in endothelial cells. Future studies could therefore use the imaging technique developed by Yokota, Nakajima et al. to investigate how blood flow influences the development of new blood vessels. DOI:http://dx.doi.org/10.7554/eLife.08817.002
Collapse
Affiliation(s)
- Yasuhiro Yokota
- Department of Cell Biology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan
| | - Hiroyuki Nakajima
- Department of Cell Biology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan
| | - Yuki Wakayama
- Department of Cell Biology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan
| | - Akira Muto
- Division of Molecular and Developmental Biology, National Institute of Genetics, Mishima, Japan.,Department of Genetics, SOKENDAI (The Graduate University for Advanced Studies), National Institute of Genetics, Mishima, Japan
| | - Koichi Kawakami
- Division of Molecular and Developmental Biology, National Institute of Genetics, Mishima, Japan.,Department of Genetics, SOKENDAI (The Graduate University for Advanced Studies), National Institute of Genetics, Mishima, Japan
| | - Shigetomo Fukuhara
- Department of Cell Biology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan
| | - Naoki Mochizuki
- Department of Cell Biology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan.,AMED-CREST, Japan Agency for Medical Research and Development, Suita, Japan
| |
Collapse
|
112
|
Agricola ZN, Jagpal AK, Allbee AW, Prewitt AR, Shifley ET, Rankin SA, Zorn AM, Kenny AP. Identification of genes expressed in the migrating primitive myeloid lineage of Xenopus laevis. Dev Dyn 2015; 245:47-55. [PMID: 26264370 DOI: 10.1002/dvdy.24314] [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: 03/06/2015] [Revised: 06/23/2015] [Accepted: 07/13/2015] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND During primitive hematopoiesis in Xenopus, cebpa and spib expressing myeloid cells emerge from the anterior ventral blood island. Primitive myeloid cells migrate throughout the embryo and are critical for immunity, healing, and development. Although definitive hematopoiesis has been studied extensively, molecular mechanisms leading to the migration of primitive myelocytes remain poorly understood. We hypothesized these cells have specific extracellular matrix modifying and cell motility gene expression. RESULTS In situ hybridization screens of transcripts expressed in Xenopus foregut mesendoderm at stage 23 identified seven genes with restricted expression in primitive myeloid cells: destrin; coronin actin binding protein, 1a; formin-like 1; ADAM metallopeptidase domain 28; cathepsin S; tissue inhibitor of metalloproteinase-1; and protein tyrosine phosphatase nonreceptor 6. A detailed in situ hybridization analysis revealed these genes are initially expressed in the aVBI but become dispersed throughout the embryo as the primitive myeloid cells become migratory, similar to known myeloid markers. Morpholino-mediated loss-of-function and mRNA-mediated gain-of-function studies revealed the identified genes are downstream of Spib.a and Cebpa, key transcriptional regulators of the myeloid lineage. CONCLUSIONS We have identified genes specifically expressed in migratory primitive myeloid progenitors, providing tools to study how different gene networks operate in these primitive myelocytes during development and immunity.
Collapse
Affiliation(s)
- Zachary N Agricola
- Perinatal Institute, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio.,Division of Neonatology, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio
| | - Amrita K Jagpal
- Perinatal Institute, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio.,Division of Neonatology, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio
| | - Andrew W Allbee
- Perinatal Institute, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio.,Division of Neonatology, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio
| | - Allison R Prewitt
- Perinatal Institute, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio.,Division of Neonatology, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio
| | - Emily T Shifley
- Perinatal Institute, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio.,Division of Developmental Biology, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio
| | - Scott A Rankin
- Perinatal Institute, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio.,Division of Developmental Biology, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio
| | - Aaron M Zorn
- Perinatal Institute, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio.,Division of Developmental Biology, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio
| | - Alan P Kenny
- Perinatal Institute, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio.,Division of Neonatology, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio
| |
Collapse
|
113
|
Ao JY, Chai ZT, Zhang YY, Zhu XD, Kong LQ, Zhang N, Ye BG, Cai H, Gao DM, Sun HC. Robo1 promotes angiogenesis in hepatocellular carcinoma through the Rho family of guanosine triphosphatases' signaling pathway. Tumour Biol 2015; 36:8413-24. [PMID: 26022159 DOI: 10.1007/s13277-015-3601-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Accepted: 05/20/2015] [Indexed: 02/05/2023] Open
Abstract
Robo1 is a member of the Robo immunoglobulin superfamily of proteins, and it plays an important role in angiogenesis and cancer. In this study, we investigate the role of roundabout 1 (Robo1) in tumor angiogenesis in hepatocellular carcinoma (HCC). Firstly, the relationship between Robo1 expression on tumors and patient's survival and endothelial cells in tumor blood vessels and patient's survival was studied. Secondly, Robo1 was overexpressed or knocked down in human umbilical vein endothelial cells (HUVECs). Cell proliferation, motility, and tube formation were compared in HUVEC with different Robo1 expression. Also, HUVECs with different Robo1 expression were mixed with HCCLM3 and HepG2 hepatoma cells and then implanted in a nude mouse model to examine the effects of Robo1 in endothelial cells on tumor growth and angiogenesis. Cell motility-related molecules were studied to investigate the potential mechanism how Robo1 promoted tumor angiogenesis in HCC. The disease-free survival of the patients with high Robo1 expression in tumoral endothelial cells was significantly shorter than that of those with low expression (P = 0.021). Overexpression of Robo1 in HUVECs resulted in increased proliferation, motility, and tube formation in vitro. In the implanted mixture of tumor cells and HUVECs with an increased Robo1 expression, tumor growth and microvessel density were enhanced compared with controls. Robo1 promoted cell division cycle 42 (Cdc42) expression in HUVECs, and a distorted actin cytoskeleton in HUVECs was observed when Robo1 expression was suppressed. In conclusion, Robo1 promoted angiogenesis in HCC mediated by Cdc42.
Collapse
Affiliation(s)
- Jian-Yang Ao
- Liver Cancer Institute and Zhongshan Hospital, Fudan University, 180 Fenglin Road, Shanghai, 200032, China
- Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Shanghai, 200032, China
- The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, China
| | - Zong-Tao Chai
- Liver Cancer Institute and Zhongshan Hospital, Fudan University, 180 Fenglin Road, Shanghai, 200032, China
- Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Shanghai, 200032, China
- Changhai Hospital, Second Military Medical University, Shanghai, 200433, China
| | - Yuan-Yuan Zhang
- Liver Cancer Institute and Zhongshan Hospital, Fudan University, 180 Fenglin Road, Shanghai, 200032, China
- Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Shanghai, 200032, China
| | - Xiao-Dong Zhu
- Liver Cancer Institute and Zhongshan Hospital, Fudan University, 180 Fenglin Road, Shanghai, 200032, China
- Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Shanghai, 200032, China
| | - Ling-Qun Kong
- Department of Hepatobiliary Surgery, Binzhou Medical College Affiliated Hospital, Binzhou, Shandong, 256610, China
| | - Ning Zhang
- Liver Cancer Institute and Zhongshan Hospital, Fudan University, 180 Fenglin Road, Shanghai, 200032, China
- Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Shanghai, 200032, China
| | - Bo-Gen Ye
- Liver Cancer Institute and Zhongshan Hospital, Fudan University, 180 Fenglin Road, Shanghai, 200032, China
- Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Shanghai, 200032, China
| | - Hao Cai
- Liver Cancer Institute and Zhongshan Hospital, Fudan University, 180 Fenglin Road, Shanghai, 200032, China
- Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Shanghai, 200032, China
| | - Dong-mei Gao
- Liver Cancer Institute and Zhongshan Hospital, Fudan University, 180 Fenglin Road, Shanghai, 200032, China
- Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Shanghai, 200032, China
| | - Hui-Chuan Sun
- Liver Cancer Institute and Zhongshan Hospital, Fudan University, 180 Fenglin Road, Shanghai, 200032, China.
- Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Shanghai, 200032, China.
| |
Collapse
|
114
|
Goi M, Childs SJ. Patterning mechanisms of the sub-intestinal venous plexus in zebrafish. Dev Biol 2015; 409:114-128. [PMID: 26477558 DOI: 10.1016/j.ydbio.2015.10.017] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Revised: 10/05/2015] [Accepted: 10/12/2015] [Indexed: 12/31/2022]
Abstract
Despite considerable interest in angiogenesis, organ-specific angiogenesis remains less well characterized. The vessels that absorb nutrients from the yolk and later provide blood supply to the developing digestive system are primarily venous in origin. In zebrafish, these are the vessels of the Sub-intestinal venous plexus (SIVP) and they represent a new candidate model to gain an insight into the mechanisms of venous angiogenesis. Unlike other vessel beds in zebrafish, the SIVP is not stereotypically patterned and lacks obvious sources of patterning information. However, by examining the area of vessel coverage, number of compartments, proliferation and migration speed we have identified common developmental steps in SIVP formation. We applied our analysis of SIVP development to obd mutants that have a mutation in the guidance receptor PlexinD1. obd mutants show dysregulation of nearly all parameters of SIVP formation. We show that the SIVP responds to a unique combination of pathways that control both arterial and venous growth in other systems. Blocking Shh, Notch and Pdgf signaling has no effect on SIVP growth. However Vegf promotes sprouting of the predominantly venous plexus and Bmp promotes outgrowth of the structure. We propose that the SIVP is a unique model to understand novel mechanisms utilized in organ-specific angiogenesis.
Collapse
Affiliation(s)
- Michela Goi
- Department of Biochemistry and Molecular Biology and Alberta Children's Hospital Research Institute, University of Calgary, 3330 Hospital Drive NW, Calgary, AB, Canada T2N 4N1
| | - Sarah J Childs
- Department of Biochemistry and Molecular Biology and Alberta Children's Hospital Research Institute, University of Calgary, 3330 Hospital Drive NW, Calgary, AB, Canada T2N 4N1.
| |
Collapse
|
115
|
Ridley AJ. Rho GTPase signalling in cell migration. Curr Opin Cell Biol 2015; 36:103-12. [PMID: 26363959 PMCID: PMC4728192 DOI: 10.1016/j.ceb.2015.08.005] [Citation(s) in RCA: 549] [Impact Index Per Article: 61.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Revised: 08/18/2015] [Accepted: 08/23/2015] [Indexed: 01/15/2023]
Abstract
Cells migrate in multiple different ways depending on their environment, which includes the extracellular matrix composition, interactions with other cells, and chemical stimuli. For all types of cell migration, Rho GTPases play a central role, although the relative contribution of each Rho GTPase depends on the environment and cell type. Here, I review recent advances in our understanding of how Rho GTPases contribute to different types of migration, comparing lamellipodium-driven versus bleb-driven migration modes. I also describe how cells migrate across the endothelium. In addition to Rho, Rac and Cdc42, which are well known to regulate migration, I discuss the roles of other less-well characterized members of the Rho family.
Collapse
Affiliation(s)
- Anne J Ridley
- Randall Division of Cell and Molecular Biophysics, King's College London, New Hunt's House, Guy's Campus, London SE1 1UL, UK.
| |
Collapse
|
116
|
Hasan SS, Siekmann AF. The same but different: signaling pathways in control of endothelial cell migration. Curr Opin Cell Biol 2015; 36:86-92. [DOI: 10.1016/j.ceb.2015.07.009] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Revised: 07/16/2015] [Accepted: 07/19/2015] [Indexed: 11/24/2022]
|
117
|
Abstract
Cells migrate in multiple different ways depending on their environment, which includes the extracellular matrix composition, interactions with other cells, and chemical stimuli. For all types of cell migration, Rho GTPases play a central role, although the relative contribution of each Rho GTPase depends on the environment and cell type. Here, I review recent advances in our understanding of how Rho GTPases contribute to different types of migration, comparing lamellipodium-driven versus bleb-driven migration modes. I also describe how cells migrate across the endothelium. In addition to Rho, Rac and Cdc42, which are well known to regulate migration, I discuss the roles of other less-well characterized members of the Rho family.
Collapse
Affiliation(s)
- Anne J Ridley
- Randall Division of Cell and Molecular Biophysics, King's College London, New Hunt's House, Guy's Campus, London SE1 1UL, UK.
| |
Collapse
|
118
|
The Formin FMNL3 Controls Early Apical Specification in Endothelial Cells by Regulating the Polarized Trafficking of Podocalyxin. Curr Biol 2015; 25:2325-31. [PMID: 26299518 DOI: 10.1016/j.cub.2015.07.045] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Revised: 05/27/2015] [Accepted: 07/16/2015] [Indexed: 01/11/2023]
Abstract
Angiogenesis is the fundamental process by which new blood vessels form from pre-existing vasculature. It plays a critical role in the formation of the vasculature during development and is triggered in response to tissue hypoxia in adult organisms. This process requires complex and coordinated regulation of the endothelial cell cytoskeleton to control cell shape and polarity. In our previous work, we showed that the cytoskeletal regulator FMNL3/FRL2 controls the alignment of stabilized microtubules during polarized endothelial cell elongation and that depletion of FMNL3 retards elongation of the intersegmental vessels in zebrafish. Recent work has shown that FMNL3 is also needed for vascular lumen formation, a critical element of the formation of functional vessels. Here, we show that FMNL3 interacts with Cdc42 and RhoJ, two Rho family GTPases known to be required for lumen formation. FMNL3 and RhoJ are concentrated at the early apical surface, or AMIS, and regulate the formation of radiating actin cables from this site. In diverse biological systems, formins mediate polarized trafficking through the generation of similar actin filaments tracks. We show that FMNL3 and RhoJ are required for polarized trafficking of podocalyxin to the early apical surface--an important event in vascular lumenogenesis.
Collapse
|
119
|
Jacquemet G, Hamidi H, Ivaska J. Filopodia in cell adhesion, 3D migration and cancer cell invasion. Curr Opin Cell Biol 2015; 36:23-31. [PMID: 26186729 DOI: 10.1016/j.ceb.2015.06.007] [Citation(s) in RCA: 351] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Revised: 05/23/2015] [Accepted: 06/27/2015] [Indexed: 01/09/2023]
Abstract
This review discusses recent advances in our understanding of the role filopodia and filopodia-like structures in cell adhesion and three dimensional (3D) cell migration both in vitro and in vivo. In particular, we focus on recent advances demonstrating that filopodia are involved in substrate tethering and environment sensing in vivo. We further discuss the emerging role of filopodia and filopodial proteins in tumor dissemination as mounting in vitro, in vivo and clinical evidence suggest that filopodia drive cancer cell invasion and highlight filopodia proteins as attractive therapeutic targets. Finally, we outline outstanding questions that remain to be addressed to elucidate the role of filopodia during 3D cell migration.
Collapse
Affiliation(s)
- Guillaume Jacquemet
- Turku Centre for Biotechnology, University of Turku, Tykistökatu 6A, FIN-20520 Turku, Finland
| | - Hellyeh Hamidi
- Turku Centre for Biotechnology, University of Turku, Tykistökatu 6A, FIN-20520 Turku, Finland
| | - Johanna Ivaska
- Turku Centre for Biotechnology, University of Turku, Tykistökatu 6A, FIN-20520 Turku, Finland.
| |
Collapse
|
120
|
Fukuhara S, Fukui H, Wakayama Y, Ando K, Nakajima H, Mochizuki N. Looking back and moving forward: Recent advances in understanding of cardiovascular development by imaging of zebrafish. Dev Growth Differ 2015; 57:333-40. [DOI: 10.1111/dgd.12210] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Revised: 03/04/2015] [Accepted: 03/04/2015] [Indexed: 12/26/2022]
Affiliation(s)
- Shigetomo Fukuhara
- Department of Cell Biology; National Cerebral and Cardiovascular Center Research Institute; 5-7-1 Fujishirodai Suita Osaka 565-8565 Japan
| | - Hajime Fukui
- Department of Cell Biology; National Cerebral and Cardiovascular Center Research Institute; 5-7-1 Fujishirodai Suita Osaka 565-8565 Japan
| | - Yuki Wakayama
- Department of Cell Biology; National Cerebral and Cardiovascular Center Research Institute; 5-7-1 Fujishirodai Suita Osaka 565-8565 Japan
| | - Koji Ando
- Department of Cell Biology; National Cerebral and Cardiovascular Center Research Institute; 5-7-1 Fujishirodai Suita Osaka 565-8565 Japan
| | - Hiroyuki Nakajima
- Department of Cell Biology; National Cerebral and Cardiovascular Center Research Institute; 5-7-1 Fujishirodai Suita Osaka 565-8565 Japan
| | - Naoki Mochizuki
- Department of Cell Biology; National Cerebral and Cardiovascular Center Research Institute; 5-7-1 Fujishirodai Suita Osaka 565-8565 Japan
- JST-CREST; National Cerebral and Cardiovascular Center; 5-7-1 Suita Osaka 565-8565 Japan
| |
Collapse
|
121
|
Abstract
The morpholino anti-sense technology has been used extensively to test gene function. The zebrafish model allows a detailed comparison of knockdown (anti-sense) and knockout (mutation) effects. Recent studies reveal that these two approaches can often lead to surprisingly different phenotypes, thus raising a number of important questions.
Collapse
|
122
|
Phng LK, Gebala V, Bentley K, Philippides A, Wacker A, Mathivet T, Sauteur L, Stanchi F, Belting HG, Affolter M, Gerhardt H. Formin-mediated actin polymerization at endothelial junctions is required for vessel lumen formation and stabilization. Dev Cell 2015; 32:123-32. [PMID: 25584798 DOI: 10.1016/j.devcel.2014.11.017] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Revised: 07/31/2014] [Accepted: 11/10/2014] [Indexed: 12/31/2022]
Abstract
During blood vessel formation, endothelial cells (ECs) establish cell-cell junctions and rearrange to form multicellular tubes. Here, we show that during lumen formation, the actin nucleator and elongation factor, formin-like 3 (fmnl3), localizes to EC junctions, where filamentous actin (F-actin) cables assemble. Fluorescent actin reporters and fluorescence recovery after photobleaching experiments in zebrafish embryos identified a pool of dynamic F-actin with high turnover at EC junctions in vessels. Knockdown of fmnl3 expression, chemical inhibition of formin function, and expression of dominant-negative fmnl3 revealed that formin activity maintains a stable F-actin content at EC junctions by continual polymerization of F-actin cables. Reduced actin polymerization leads to destabilized endothelial junctions and consequently to failure in blood vessel lumenization and lumen instability. Our findings highlight the importance of formin activity in blood vessel morphogenesis.
Collapse
Affiliation(s)
- Li-Kun Phng
- Vascular Patterning Laboratory, Vesalius Research Center, VIB, Department of Oncology, KU Leuven, Herestraat 49, 3000 Leuven, Belgium
| | - Véronique Gebala
- Vascular Biology Laboratory, London Research Institute, Cancer Research UK, London WC2A 3LY, UK
| | - Katie Bentley
- Computational Biology Laboratory, Center for Vascular Biology Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Andrew Philippides
- Centre for Computational Neuroscience and Robotics, Department of Informatics, University of Sussex, Brighton BN1 9QJ, UK
| | - Andrin Wacker
- Vascular Patterning Laboratory, Vesalius Research Center, VIB, Department of Oncology, KU Leuven, Herestraat 49, 3000 Leuven, Belgium
| | - Thomas Mathivet
- Vascular Patterning Laboratory, Vesalius Research Center, VIB, Department of Oncology, KU Leuven, Herestraat 49, 3000 Leuven, Belgium
| | - Loïc Sauteur
- Biozentrum der Universität Basel, Klingelbergstrasse 50/70, 4056 Basel, Switzerland
| | - Fabio Stanchi
- Vascular Patterning Laboratory, Vesalius Research Center, VIB, Department of Oncology, KU Leuven, Herestraat 49, 3000 Leuven, Belgium
| | - Heinz-Georg Belting
- Biozentrum der Universität Basel, Klingelbergstrasse 50/70, 4056 Basel, Switzerland
| | - Markus Affolter
- Biozentrum der Universität Basel, Klingelbergstrasse 50/70, 4056 Basel, Switzerland
| | - Holger Gerhardt
- Vascular Patterning Laboratory, Vesalius Research Center, VIB, Department of Oncology, KU Leuven, Herestraat 49, 3000 Leuven, Belgium; Vascular Biology Laboratory, London Research Institute, Cancer Research UK, London WC2A 3LY, UK.
| |
Collapse
|