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Biniazan F, Stoian A, Haykal S. Adipose-Derived Stem Cells: Angiogenetic Potential and Utility in Tissue Engineering. Int J Mol Sci 2024; 25:2356. [PMID: 38397032 PMCID: PMC10889096 DOI: 10.3390/ijms25042356] [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: 12/19/2023] [Revised: 02/07/2024] [Accepted: 02/13/2024] [Indexed: 02/25/2024] Open
Abstract
Adipose tissue (AT) is a large and important energy storage organ as well as an endocrine organ with a critical role in many processes. Additionally, AT is an enormous and easily accessible source of multipotent cell types used in our day for all types of tissue regeneration. The ability of adipose-derived stem cells (ADSCs) to differentiate into other types of cells, such as endothelial cells (ECs), vascular smooth muscle cells, or cardiomyocytes, is used in tissue engineering in order to promote/stimulate the process of angiogenesis. Being a key for future successful clinical applications, functional vascular networks in engineered tissue are targeted by numerous in vivo and ex vivo studies. The article reviews the angiogenic potential of ADSCs and explores their capacity in the field of tissue engineering (TE).
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Affiliation(s)
- Felor Biniazan
- Latner Thoracic Research Laboratories, Division of Thoracic Surgery, Toronto General Hospital Research Institute, University Health Network, 200 Elizabeth Street Suite 8N-869, Toronto, ON M5G2C4, Canada; (F.B.); (A.S.)
| | - Alina Stoian
- Latner Thoracic Research Laboratories, Division of Thoracic Surgery, Toronto General Hospital Research Institute, University Health Network, 200 Elizabeth Street Suite 8N-869, Toronto, ON M5G2C4, Canada; (F.B.); (A.S.)
| | - Siba Haykal
- Latner Thoracic Research Laboratories, Division of Thoracic Surgery, Toronto General Hospital Research Institute, University Health Network, 200 Elizabeth Street Suite 8N-869, Toronto, ON M5G2C4, Canada; (F.B.); (A.S.)
- Division of Plastic and Reconstructive Surgery, Department of Surgery, University of Toronto, 200 Elizabeth Street Suite 8N-869, Toronto, ON M5G2C4, Canada
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2
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Angiogenic Effects and Crosstalk of Adipose-Derived Mesenchymal Stem/Stromal Cells and Their Extracellular Vesicles with Endothelial Cells. Int J Mol Sci 2021; 22:ijms221910890. [PMID: 34639228 PMCID: PMC8509224 DOI: 10.3390/ijms221910890] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 10/02/2021] [Accepted: 10/04/2021] [Indexed: 12/13/2022] Open
Abstract
Adipose-derived mesenchymal stem/stromal cells (ASCs) are an adult stem cell population able to self-renew and differentiate into numerous cell lineages. ASCs provide a promising future for therapeutic angiogenesis due to their ability to promote blood vessel formation. Specifically, their ability to differentiate into endothelial cells (ECs) and pericyte-like cells and to secrete angiogenesis-promoting growth factors and extracellular vesicles (EVs) makes them an ideal option in cell therapy and in regenerative medicine in conditions including tissue ischemia. In recent angiogenesis research, ASCs have often been co-cultured with an endothelial cell (EC) type in order to form mature vessel-like networks in specific culture conditions. In this review, we introduce co-culture systems and co-transplantation studies between ASCs and ECs. In co-cultures, the cells communicate via direct cell-cell contact or via paracrine signaling. Most often, ASCs are found in the perivascular niche lining the vessels, where they stabilize the vascular structures and express common pericyte surface proteins. In co-cultures, ASCs modulate endothelial cells and induce angiogenesis by promoting tube formation, partly via secretion of EVs. In vivo co-transplantation of ASCs and ECs showed improved formation of functional vessels over a single cell type transplantation. Adipose tissue as a cell source for both mesenchymal stem cells and ECs for co-transplantation serves as a prominent option for therapeutic angiogenesis and blood perfusion in vivo.
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3
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Bulut GB, Alencar GF, Owsiany KM, Nguyen AT, Karnewar S, Haskins RM, Waller LK, Cherepanova OA, Deaton RA, Shankman LS, Keller SR, Owens GK. KLF4 (Kruppel-Like Factor 4)-Dependent Perivascular Plasticity Contributes to Adipose Tissue inflammation. Arterioscler Thromb Vasc Biol 2021; 41:284-301. [PMID: 33054397 PMCID: PMC7769966 DOI: 10.1161/atvbaha.120.314703] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Smooth muscle cells and pericytes display remarkable plasticity during injury and disease progression. Here, we tested the hypothesis that perivascular cells give rise to Klf4-dependent macrophage-like cells that augment adipose tissue (AT) inflammation and metabolic dysfunction associated with diet-induced obesity (DIO). Approach and Results: Using Myh11-CreERT2 eYFP (enhanced yellow fluorescent protein) mice and flow cytometry of the stromovascular fraction of epididymal AT, we observed a large fraction of smooth muscle cells and pericytes lineage traced eYFP+ cells expressing macrophage markers. Subsequent single-cell RNA sequencing, however, showed that the majority of these cells had no detectable eYFP transcript. Further exploration revealed that intraperitoneal injection of tamoxifen in peanut oil, used for generating conditional knockout or reporter mice in thousands of previous studies, resulted in large increase in the autofluorescence and false identification of macrophages within epididymal AT as being eYFP+; and unintended proinflammatory consequences. Using newly generated Myh11-DreERT2tdTomato mice given oral tamoxifen, we virtually eliminated the problem with autofluorescence and identified 8 perivascular cell dominated clusters, half of which were altered upon DIO. Given that perivascular cell KLF4 (kruppel-like factor 4) can have beneficial or detrimental effects, we tested its role in obesity-associated AT inflammation. While smooth muscle cells and pericytes-specific Klf4 knockout (smooth muscle cells and pericytes Klf4Δ/Δ) mice were not protected from DIO, they displayed improved glucose tolerance upon DIO, and showed marked decreases in proinflammatory macrophages and increases in LYVE1+ lymphatic endothelial cells in the epididymal AT. CONCLUSIONS Perivascular cells within the AT microvasculature dynamically respond to DIO and modulate tissue inflammation and metabolism in a KLF4-dependent manner.
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Affiliation(s)
- Gamze B. Bulut
- The Robert M. Berne Cardiovascular Research Center, University of Virginia
| | - Gabriel F. Alencar
- The Robert M. Berne Cardiovascular Research Center, University of Virginia
| | | | - Anh T. Nguyen
- The Robert M. Berne Cardiovascular Research Center, University of Virginia
| | - Santosh Karnewar
- The Robert M. Berne Cardiovascular Research Center, University of Virginia
| | - Ryan M. Haskins
- The Robert M. Berne Cardiovascular Research Center, University of Virginia
| | - Lillian K. Waller
- The Robert M. Berne Cardiovascular Research Center, University of Virginia
| | - Olga A. Cherepanova
- Cardiovascular and Metabolic Sciences Lerner Research Institute, Cleveland Clinic
| | - Rebecca A. Deaton
- The Robert M. Berne Cardiovascular Research Center, University of Virginia
| | - Laura S. Shankman
- The Robert M. Berne Cardiovascular Research Center, University of Virginia
| | - Susanna R. Keller
- Department of Medicine-Division of Endocrinology and Metabolism, University of Virginia
| | - Gary K. Owens
- The Robert M. Berne Cardiovascular Research Center, University of Virginia
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4
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Lu D, Ho ES, Mai H, Zang J, Liu Y, Li Y, Yang B, Ding Y, Tsang CK, Xu A. Identification of Blood Circular RNAs as Potential Biomarkers for Acute Ischemic Stroke. Front Neurosci 2020; 14:81. [PMID: 32116524 PMCID: PMC7015875 DOI: 10.3389/fnins.2020.00081] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 01/21/2020] [Indexed: 12/11/2022] Open
Abstract
Many hospitals lack facilities for accurate diagnosis of acute ischemic stroke (AIS). Circular RNA (circRNA) is highly expressed in the brain and is closely associated with stroke. In this study, we examined whether the blood-borne circRNAs could be promising candidates as adjunctive diagnostic biomarkers and their pathophysiological roles after stroke. We profiled the blood circRNA expression in mice subjected to experimental focal cerebral ischemia and validated the selected circRNAs in AIS patients. We demonstrated that 128, 198, and 789 circRNAs were significantly altered at 5 min, 3 h, and 24 h after ischemic stroke, respectively. Our bioinformatics analysis revealed that the circRNA-targeted genes were associated with the Hippo signaling pathway, extracellular matrix-receptor interaction, and fatty acid metabolism at 5 min, 3 h and 24 h after ischemic stroke, respectively. We verified that many of these circRNAs existed in the mouse brain. Furthermore, we found that most of the predicted circRNA-miRNA interactions apparently exhibited functional roles in terms of regulation of their target gene expression in the brain. We also verified that many of these mouse circRNAs were conserved in human. Finally, we found that circBBS2 and circPHKA2 were differentially expressed in the blood of AIS patients. These results demonstrate that blood circRNAs may serve as potential biomarkers for AIS diagnosis and reveal the pathophysiological responses in the brain after ischemic stroke.
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Affiliation(s)
- Dan Lu
- Department of Neurology and Stroke Center, The First Affiliated Hospital of Jinan University, Guangzhou, China.,Clinical Neuroscience Institute, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Eric S Ho
- Department of Biology, Lafayette College, Easton, PA, United States.,Department of Computer Science, Lafayette College, Easton, PA, United States
| | - Hongcheng Mai
- Department of Neurology and Stroke Center, The First Affiliated Hospital of Jinan University, Guangzhou, China.,Clinical Neuroscience Institute, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Jiankun Zang
- Department of Neurology and Stroke Center, The First Affiliated Hospital of Jinan University, Guangzhou, China.,Clinical Neuroscience Institute, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Yanfang Liu
- Department of Neurology and Stroke Center, The First Affiliated Hospital of Jinan University, Guangzhou, China.,Clinical Neuroscience Institute, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Yufeng Li
- Department of Neurology and Stroke Center, The First Affiliated Hospital of Jinan University, Guangzhou, China.,Clinical Neuroscience Institute, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Bing Yang
- Department of Neurology and Stroke Center, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Yan Ding
- Department of Neurology and Stroke Center, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Chi Kwan Tsang
- Clinical Neuroscience Institute, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Anding Xu
- Department of Neurology and Stroke Center, The First Affiliated Hospital of Jinan University, Guangzhou, China.,Clinical Neuroscience Institute, The First Affiliated Hospital of Jinan University, Guangzhou, China
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5
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Heldin CH, Lennartsson J, Westermark B. Involvement of platelet-derived growth factor ligands and receptors in tumorigenesis. J Intern Med 2018; 283:16-44. [PMID: 28940884 DOI: 10.1111/joim.12690] [Citation(s) in RCA: 111] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Platelet-derived growth factor (PDGF) isoforms and their receptors have important roles during embryogenesis, particularly in the development of various mesenchymal cell types in different organs. In the adult, PDGF stimulates wound healing and regulates tissue homeostasis. However, overactivity of PDGF signalling is associated with malignancies and other diseases characterized by excessive cell proliferation, such as fibrotic conditions and atherosclerosis. In certain tumours, genetic or epigenetic alterations of the genes for PDGF ligands and receptors drive tumour cell proliferation and survival. Examples include the rare skin tumour dermatofibrosarcoma protuberance, which is driven by autocrine PDGF stimulation due to translocation of a PDGF gene, and certain gastrointestinal stromal tumours and leukaemias, which are driven by constitute activation of PDGF receptors due to point mutations and formation of fusion proteins of the receptors, respectively. Moreover, PDGF stimulates cells in tumour stroma and promotes angiogenesis as well as the development of cancer-associated fibroblasts, both of which promote tumour progression. Inhibitors of PDGF signalling may thus be of clinical usefulness in the treatment of certain tumours.
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Affiliation(s)
- C-H Heldin
- Ludwig Institute for Cancer Research, Science for Life Laboratory, Uppsala University, Uppsala, Sweden.,Department of Medical Biochemistry and Microbiology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - J Lennartsson
- Ludwig Institute for Cancer Research, Science for Life Laboratory, Uppsala University, Uppsala, Sweden.,Department of Pharmaceutical Biosciences, Uppsala University, Uppsala, Sweden
| | - B Westermark
- Department of Genetics and Pathology, Uppsala University, Uppsala, Sweden
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6
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Shen EM, McCloskey KE. Development of Mural Cells: From In Vivo Understanding to In Vitro Recapitulation. Stem Cells Dev 2017; 26:1020-1041. [DOI: 10.1089/scd.2017.0020] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Affiliation(s)
- Edwin M. Shen
- Graduate Program in Biological Engineering and Small-scale Technologies
| | - Kara E. McCloskey
- Graduate Program in Biological Engineering and Small-scale Technologies
- School of Engineering, University of California, Merced, Merced, California
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7
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Ma X, Jiang C, Li Y, Feng L, Liu J, Wang J. Inhibition effect of tacrolimus and platelet-derived growth factor-BB on restenosis after vascular intimal injury. Biomed Pharmacother 2017. [PMID: 28633129 DOI: 10.1016/j.biopha.2017.06.027] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Excessive proliferation and migration of vascular smooth muscle cells(VSMCs) and delayed proliferation and migration of endothelial cells(ECs) were the main cause of restenosis after endovascular interventional therapy. Since tacrolimus has proved to be more sensitive to inhibiting VSMCs' proliferation,and platelet-derived growth factor-BB(PDGF-BB) benefitted ECs' and VSMCs' proliferation, this study was aimed to identify combined effect of tacrolimus and PDGF-BB, investigate any mechanisms underneath and demonstrate combined effect of two drugs in vivo. As the results showed we confirmed differential effect of PDGF-BB and tacrolimus on ECs and VSMCs. On the concentration level of 2-5μg/ml tacrolimus plus 10ng/ml PDGF-BB, combination of drugs could effectively promote ECs proliferation and migration, and meanwhile inhibit VSMCs proliferation and migration, and the inhibition of p-mTOR's expression within VSMCs played an important role in this differentiated effect. Raising concentration level of PDGF-BB would weaken inhibitory effect of tacrolimus on both kinds of cell. For injured intima, the mix solution of two drugs could promote intima healing and suppress excessive intimal hyperplasia.
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Affiliation(s)
- Xu Ma
- Department of Interventional Radiology, The Sixth People's Hospital Affiliated to Shanghai Jiaotong University, No 600 Yishan road, Xuhui District, Shanghai, 200233, China
| | - Chunyu Jiang
- Department of Interventional Radiology, The Sixth People's Hospital Affiliated to Shanghai Jiaotong University, No 600 Yishan road, Xuhui District, Shanghai, 200233, China
| | - Yuehua Li
- Department of Interventional Radiology, The Sixth People's Hospital Affiliated to Shanghai Jiaotong University, No 600 Yishan road, Xuhui District, Shanghai, 200233, China
| | - Lishuai Feng
- Department of Interventional Radiology, The Sixth People's Hospital Affiliated to Shanghai Jiaotong University, No 600 Yishan road, Xuhui District, Shanghai, 200233, China
| | - Jingjing Liu
- Department of Interventional Radiology, The Sixth People's Hospital Affiliated to Shanghai Jiaotong University, No 600 Yishan road, Xuhui District, Shanghai, 200233, China
| | - Jianbo Wang
- Department of Interventional Radiology, The Sixth People's Hospital Affiliated to Shanghai Jiaotong University, No 600 Yishan road, Xuhui District, Shanghai, 200233, China.
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8
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Butler LM, Hallström BM, Fagerberg L, Pontén F, Uhlén M, Renné T, Odeberg J. Analysis of Body-wide Unfractionated Tissue Data to Identify a Core Human Endothelial Transcriptome. Cell Syst 2016; 3:287-301.e3. [PMID: 27641958 DOI: 10.1016/j.cels.2016.08.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 05/23/2016] [Accepted: 08/03/2016] [Indexed: 12/11/2022]
Abstract
Endothelial cells line blood vessels and regulate hemostasis, inflammation, and blood pressure. Proteins critical for these specialized functions tend to be predominantly expressed in endothelial cells across vascular beds. Here, we present a systems approach to identify a panel of human endothelial-enriched genes using global, body-wide transcriptomics data from 124 tissue samples from 32 organs. We identified known and unknown endothelial-enriched gene transcripts and used antibody-based profiling to confirm expression across vascular beds. The majority of identified transcripts could be detected in cultured endothelial cells from various vascular beds, and we observed maintenance of relative expression in early passage cells. In summary, we describe a widely applicable method to determine cell-type-specific transcriptome profiles in a whole-organism context, based on differential abundance across tissues. We identify potential vascular drug targets or endothelial biomarkers and highlight candidates for functional studies to increase understanding of the endothelium in health and disease.
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Affiliation(s)
- Lynn Marie Butler
- Institute for Clinical Chemistry and Laboratory Medicine, University Medical Centre Hamburg-Eppendorf, 20246 Hamburg, Germany; Clinical Chemistry and Blood Coagulation, Department of Molecular Medicine and Surgery, Karolinska Institute, 171 76 Stockholm, Sweden.
| | - Björn Mikael Hallström
- Science for Life Laboratory, School of Biotechnology, Royal Institute of Technology (KTH), 171 21 Stockholm, Sweden
| | - Linn Fagerberg
- Science for Life Laboratory, School of Biotechnology, Royal Institute of Technology (KTH), 171 21 Stockholm, Sweden
| | - Fredrik Pontén
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, 751 85 Uppsala, Sweden
| | - Mathias Uhlén
- Science for Life Laboratory, School of Biotechnology, Royal Institute of Technology (KTH), 171 21 Stockholm, Sweden
| | - Thomas Renné
- Institute for Clinical Chemistry and Laboratory Medicine, University Medical Centre Hamburg-Eppendorf, 20246 Hamburg, Germany; Clinical Chemistry and Blood Coagulation, Department of Molecular Medicine and Surgery, Karolinska Institute, 171 76 Stockholm, Sweden
| | - Jacob Odeberg
- Science for Life Laboratory, School of Biotechnology, Royal Institute of Technology (KTH), 171 21 Stockholm, Sweden; Coagulation Unit, Centre for Hematology, Karolinska University Hospital, 171 76 Stockholm, Sweden
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9
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Aydemir Turkal H, Demirer S, Dolgun A, Keceli HG. Evaluation of the adjunctive effect of platelet-rich fibrin to enamel matrix derivative in the treatment of intrabony defects. Six-month results of a randomized, split-mouth, controlled clinical study. J Clin Periodontol 2016; 43:955-964. [PMID: 27396428 DOI: 10.1111/jcpe.12598] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/07/2016] [Indexed: 02/06/2023]
Abstract
AIM This study aimed to compare the results obtained with enamel matrix derivative (EMD) and EMD + platelet-rich fibrin (PRF) in the treatment of intrabony defects (IBDs) in chronic periodontitis patients. MATERIALS AND METHODS Using a split-mouth design, 28 paired IBDs were randomly treated either with EMD or with EMD + PRF. Clinical and radiographic measurements including clinical attachment level (CAL), probing depth (PD), gingival recession (GR), defect depth (DD), defect width (DW) and defect angle (DA) were recorded at baseline (BL) and at six months following therapy. RESULTS BL clinical and radiographic measurements were similar for EMD and EMD + PRF groups. Although postsurgical measurements revealed significant reduction for PD and CAL in both groups, no intergroup difference was detected. When EMD and EMD + PRF groups were compared, defect fill was not also statistically different. CONCLUSIONS Both therapies resulted in significant clinical improvement in IBD treatment. Addition of PRF did not improve the clinical and radiographic outcomes.
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Affiliation(s)
- Humerya Aydemir Turkal
- Periodontology Department, Faculty of Dentistry, Gaziosmanpasa University, Tokat, Turkey
| | - Serhat Demirer
- Periodontology Department, Faculty of Dentistry, Kirikkale University, Kirikkale, Turkey
| | - Anil Dolgun
- Biostatistics Department, Faculty of Medicine, Hacettepe University, Ankara, Turkey
| | - Huseyin Gencay Keceli
- Periodontology Department, Faculty of Dentistry, Hacettepe University, Ankara, Turkey.
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10
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Chen S, Guo X, Imarenezor O, Imoukhuede PI. Quantification of VEGFRs, NRP1, and PDGFRs on Endothelial Cells and Fibroblasts Reveals Serum, Intra-Family Ligand, and Cross-Family Ligand Regulation. Cell Mol Bioeng 2015. [DOI: 10.1007/s12195-015-0411-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
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11
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Reck M. Nintedanib: examining the development and mechanism of action of a novel triple angiokinase inhibitor. Expert Rev Anticancer Ther 2015; 15:579-94. [PMID: 25831142 DOI: 10.1586/14737140.2015.1031218] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Antiangiogenic agents are effective standard-of-care options in several malignancies, but are generally associated with only modest improvements in survival, as well as leading to additional toxicities. Furthermore, almost all patients develop acquired resistance to therapy, possibly due to the activation of alternative proangiogenic pathways. Here we discuss: the rationale for developing nintedanib, an agent that simultaneously inhibits signaling pathways activated by platelet-derived growth factor, FGF, as well as VEGF; how its distinctive inhibitory and pharmacokinetic profile could underlie promising efficacy and tolerability observed in Phase II trials in patients with relapsed/refractory non-small cell lung cancer, advanced ovarian cancer and metastatic colorectal cancer; the ongoing Phase III program that is assessing nintedanib in these areas of major unmet medical need; and recent progress in the development of biomarkers that may predict response to nintedanib.
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Affiliation(s)
- Martin Reck
- Department of Thoracic Oncology, Lung Clinic Grosshansdorf, Airway Research Center North (ARCN), Member of the German Center for Lung Research (DZL), Grosshansdorf, Germany
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12
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Naylor AJ, McGettrick HM, Maynard WD, May P, Barone F, Croft AP, Egginton S, Buckley CD. A differential role for CD248 (Endosialin) in PDGF-mediated skeletal muscle angiogenesis. PLoS One 2014; 9:e107146. [PMID: 25243742 PMCID: PMC4171374 DOI: 10.1371/journal.pone.0107146] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Accepted: 08/12/2014] [Indexed: 11/18/2022] Open
Abstract
CD248 (Endosialin) is a type 1 membrane protein involved in developmental and pathological angiogenesis through its expression on pericytes and regulation of PDGFRβ signalling. Here we explore the function of CD248 in skeletal muscle angiogenesis. Two distinct forms of capillary growth (splitting and sprouting) can be induced separately by increasing microcirculatory shear stress (chronic vasodilator treatment) or by inducing functional overload (extirpation of a synergistic muscle). We show that CD248 is present on pericytes in muscle and that CD248-/- mice have a specific defect in capillary sprouting. In contrast, splitting angiogenesis is independent of CD248 expression. Endothelial cells respond to pro-sprouting angiogenic stimulus by up-regulating gene expression for HIF1α, angiopoietin 2 and its receptor TEK, PDGF-B and its receptor PDGFRβ; this response did not occur following a pro-splitting angiogenic stimulus. In wildtype mice, defective sprouting angiogenesis could be mimicked by blocking PDGFRβ signalling using the tyrosine kinase inhibitor Imatinib mesylate. We conclude that CD248 is required for PDGFRβ-dependant capillary sprouting but not splitting angiogenesis, and identify a new role for CD248 expressed on pericytes in the early stages of physiological angiogenesis during muscle remodelling.
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MESH Headings
- Adrenergic alpha-1 Receptor Antagonists/pharmacology
- Angiopoietin-2/genetics
- Angiopoietin-2/metabolism
- Animals
- Antigens, CD/genetics
- Antigens, CD/metabolism
- Benzamides/pharmacology
- Capillaries/drug effects
- Capillaries/metabolism
- Hypoxia-Inducible Factor 1, alpha Subunit/genetics
- Hypoxia-Inducible Factor 1, alpha Subunit/metabolism
- Imatinib Mesylate
- Mice
- Mice, Knockout
- Muscle, Skeletal/blood supply
- Muscle, Skeletal/drug effects
- Muscle, Skeletal/metabolism
- Neoplasm Proteins/genetics
- Neoplasm Proteins/metabolism
- Neovascularization, Physiologic/drug effects
- Neovascularization, Physiologic/genetics
- Pericytes/drug effects
- Pericytes/metabolism
- Piperazines/pharmacology
- Platelet-Derived Growth Factor/metabolism
- Prazosin/pharmacology
- Protein Kinase Inhibitors/pharmacology
- Pyrimidines/pharmacology
- Receptors, Platelet-Derived Growth Factor/genetics
- Receptors, Platelet-Derived Growth Factor/metabolism
- Signal Transduction/drug effects
- Signal Transduction/genetics
- Up-Regulation/drug effects
- Up-Regulation/genetics
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Affiliation(s)
- Amy J. Naylor
- Rheumatology Research Group, Centre for Translational Inflammation Research, University of Birmingham, Birmingham, West Midlands, United Kingdom
| | - Helen M. McGettrick
- Rheumatology Research Group, Centre for Translational Inflammation Research, University of Birmingham, Birmingham, West Midlands, United Kingdom
- Systems Science for Health, University of Birmingham, Birmingham, West Midlands, United Kingdom
| | - William D. Maynard
- Rheumatology Research Group, Centre for Translational Inflammation Research, University of Birmingham, Birmingham, West Midlands, United Kingdom
| | - Philippa May
- Rheumatology Research Group, Centre for Translational Inflammation Research, University of Birmingham, Birmingham, West Midlands, United Kingdom
| | - Francesca Barone
- Rheumatology Research Group, Centre for Translational Inflammation Research, University of Birmingham, Birmingham, West Midlands, United Kingdom
| | - Adam P. Croft
- Rheumatology Research Group, Centre for Translational Inflammation Research, University of Birmingham, Birmingham, West Midlands, United Kingdom
| | - Stuart Egginton
- Faculty of Biological Sciences, University of Leeds, Leeds, West Yorkshire, United Kingdom
| | - Christopher D. Buckley
- Rheumatology Research Group, Centre for Translational Inflammation Research, University of Birmingham, Birmingham, West Midlands, United Kingdom
- Systems Science for Health, University of Birmingham, Birmingham, West Midlands, United Kingdom
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13
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Hutton DL, Moore EM, Gimble JM, Grayson WL. Platelet-derived growth factor and spatiotemporal cues induce development of vascularized bone tissue by adipose-derived stem cells. Tissue Eng Part A 2013; 19:2076-86. [PMID: 23582144 DOI: 10.1089/ten.tea.2012.0752] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Vasculature is essential to the functional integration of a tissue-engineered bone graft to enable sufficient nutrient delivery and viability after implantation. Native bone and vasculature develop through intimately coupled, tightly regulated spatiotemporal cell-cell signaling. The complexity of these developmental processes has been a challenge for tissue engineers to recapitulate, resulting in poor codevelopment of both bone and vasculature within a unified graft. To address this, we cultured adipose-derived stromal/stem cells (ASCs), a clinically relevant, single cell source that has been previously investigated for its ability to give rise to vascularized bone grafts, and studied the effects of initial spatial organization of cells, the temporal addition of growth factors, and the presence of exogenous platelet-derived growth factor-BB (PDGF-BB) on the codevelopment of bone and vascular tissue structures. Human ASCs were aggregated into multicellular spheroids via the hanging drop method before encapsulation and subsequent outgrowth in fibrin gels. Cellular aggregation substantially increased vascular network density, interconnectivity, and pericyte coverage compared to monodispersed cultures. To form robust vessel networks, it was essential to culture ASCs in a purely vasculogenic medium for at least 8 days before the addition of osteogenic cues. Physiologically relevant concentrations of exogenous PDGF-BB (20 ng/mL) substantially enhanced both vascular network stability and osteogenic differentiation. Comparisons with the bone morphogenetic protein-2, another pro-osteogenic and proangiogenic growth factor, indicated that this potential to couple the formation of both lineages might be unique to PDGF-BB. Furthermore, the resulting tissue structure demonstrated the close association of mineral deposits with pre-existing vascular structures that have been described for developing tissues. This combination of a single cell source with a potent induction factor used at physiological concentrations can provide a clinically relevant approach to engineering highly vascularized bone grafts.
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Affiliation(s)
- Daphne L Hutton
- Department of Biomedical Engineering, Translational Tissue Engineering Center, School of Medicine, Johns Hopkins University, Baltimore, Maryland 21287, USA
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14
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S-nitrosoglutathione reductase (GSNOR) enhances vasculogenesis by mesenchymal stem cells. Proc Natl Acad Sci U S A 2013; 110:2834-9. [PMID: 23288904 DOI: 10.1073/pnas.1220185110] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Although nitric oxide (NO) signaling promotes differentiation and maturation of endothelial progenitor cells, its role in the differentiation of mesenchymal stem cells (MSCs) into endothelial cells remains controversial. We tested the role of NO signaling in MSCs derived from WT mice and mice homozygous for a deletion of S-nitrosoglutathione reductase (GSNOR(-/-)), a denitrosylase that regulates S-nitrosylation. GSNOR(-/-) MSCs exhibited markedly diminished capacity for vasculogenesis in an in vitro Matrigel tube-forming assay and in vivo relative to WT MSCs. This decrease was associated with down-regulation of the PDGF receptorα (PDGFRα) in GSNOR(-/-) MSCs, a receptor essential for VEGF-A action in MSCs. Pharmacologic inhibition of NO synthase with L-N(G)-nitroarginine methyl ester (L-NAME) and stimulation of growth hormone-releasing hormone receptor (GHRHR) with GHRH agonists augmented VEGF-A production and normalized tube formation in GSNOR(-/-) MSCs, whereas NO donors or PDGFR antagonist reduced tube formation ∼50% by murine and human MSCs. The antagonist also blocked the rescue of tube formation in GSNOR(-/-) MSCs by L-NAME or the GHRH agonists JI-38, MR-409, and MR-356. Therefore, GSNOR(-/-) MSCs have a deficient capacity for endothelial differentiation due to downregulation of PDGFRα related to NO/GSNOR imbalance. These findings unravel important aspects of modulation of MSCs by VEGF-A activation of the PDGFR and illustrate a paradoxical inhibitory role of S-nitrosylation signaling in MSC vasculogenesis. Accordingly, disease states characterized by NO deficiency may trigger MSC-mediated vasculogenesis. These findings have important implications for therapeutic application of GHRH agonists to ischemic disorders.
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Evaluation of tyrosine receptor kinases in the interactions of head and neck squamous cell carcinoma cells and fibroblasts. Oral Oncol 2012; 48:1242-9. [PMID: 22795534 DOI: 10.1016/j.oraloncology.2012.06.011] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2012] [Revised: 06/12/2012] [Accepted: 06/17/2012] [Indexed: 11/24/2022]
Abstract
OBJECTIVE Despite treatment advancements, disease-free survival of head and neck squamous cell carcinoma (HNSCC) has not significantly improved. This may be a result of tumor-fibroblasts interactions providing protective pathways for oncogenic cells to resist therapy. Further understanding of these relationships in HNSCC may improve effectiveness of targeted therapies. In this article, we investigated the role of several receptor tyrosine kinases (RTKs) in the interactions between HNSCC cells and supporting cells (fibroblasts). MATERIALS AND METHODS HNSCC cell lines and human tumor samples were evaluated for FGFR1/2/3, and PDGF-beta expression levels. Cell lines (FADU, SCC1, OSC19, Cal27, SCC22A) were treated with a range of physiological concentrations of dovitinib and assessed for proliferation, cytotoxicity, and apoptosis. Mice bearing HNSCC xenografts were treated with dovitinib (20 mg/kg). RESULTS Evaluation of HNSCC tumor specimens, cell lines and fibroblasts found variable expression of multiple RTKs (fibroblasts growth factor receptor, platelet derived growth factor receptor and vascular endothelial growth factor receptor) and their ligands, supporting previous theories of paracrine and autocrine signaling within the microenvironment. In a dose-dependent fashion, RTK inhibition reduced proliferation of HNSCC cell lines and fibroblast in vitro. When HNSCC cells were cocultured with fibroblasts, RTK inhibition resulted in a smaller reduction in the proliferation relative to untreated conditions. In vivo, RTK inhibition resulted in significant tumor regression and growth inhibition (p<0.05) and reduced the incidence of regional lymph node metastasis. CONCLUSION Effective treatment of HNSCC, therefore, may require inhibition of multiple RTKs in order to adequately inhibit the microenvironment's various signaling pathways.
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Wozniak A. Challenges in the current antiangiogenic treatment paradigm for patients with non-small cell lung cancer. Crit Rev Oncol Hematol 2012; 82:200-12. [DOI: 10.1016/j.critrevonc.2011.05.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2010] [Revised: 04/18/2011] [Accepted: 05/13/2011] [Indexed: 11/30/2022] Open
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Blakely C, Jahan T. Emerging antiangiogenic therapies for non-small-cell lung cancer. Expert Rev Anticancer Ther 2012; 11:1607-18. [PMID: 21999134 DOI: 10.1586/era.11.146] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Lung cancer remains the leading cause of cancer-related deaths. Antiangiogenic therapy has increasingly been studied for advanced non-small-cell lung cancer (NSCLC). Bevacizumab is the only approved antiangiogenic agent for NSCLC and has shown progression-free survival benefits in large Phase III studies and an overall survival benefit in the Phase III E4599 trial in advanced nonsquamous NSCLC. New antiangiogenic treatment strategies are being evaluated that target multiple receptors within a family (VEGF receptor [VEGFR]-1, VEGFR-2) or multiple angiogenic pathways (targets VEGFR and PDGF receptor pathways), and agents that inhibit alternative mediators of angiogenesis (integrins and established vasculature). As data become available from ongoing studies, it will be important to determine how these new antiangiogenic agents will best fit into the current NSCLC treatment paradigm.
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Affiliation(s)
- Collin Blakely
- University of California, San Francisco, Box 1705, San Francisco, CA 94143-1705, USA
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Safety Profile and Tolerability of Antiangiogenic Agents in Non–Small-Cell Lung Cancer. Clin Lung Cancer 2012; 13:96-106. [DOI: 10.1016/j.cllc.2011.08.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Revised: 08/24/2011] [Accepted: 08/29/2011] [Indexed: 11/23/2022]
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Ha JM, Kim YW, Lee DH, Yun SJ, Kim EK, Hye Jin I, Kim JH, Kim CD, Shin HK, Bae SS. Regulation of arterial blood pressure by Akt1-dependent vascular relaxation. J Mol Med (Berl) 2011; 89:1253-60. [PMID: 21842346 DOI: 10.1007/s00109-011-0798-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2011] [Revised: 07/22/2011] [Accepted: 07/27/2011] [Indexed: 12/14/2022]
Abstract
Endothelial cell-dependent vascular relaxation plays an important role in the regulation of blood pressure. Here, we show that stimulation of vascular endothelial cells with platelet-derived growth factor (PDGF) results in vascular relaxation through Akt1-dependent activation of endothelial nitric oxide synthase (eNOS) and nitric oxide (NO) production. Stimulation of both human umbilical artery endothelial cells and abdominal aortic vessels with PDGF induced NO production. PDGF-dependent production of NO was completely abolished by inhibition of phosphatidylinositol 3-kinase with wortmannin (100 nM). Stimulation of aortic vessels with PDGF resulted in the activation of Akt phosphorylation and eNOS phosphorylation: however, eNOS phosphorylation and production of NO were abolished in aortic vessels of mice lacking Akt1. PDGF strongly induced vascular relaxation in the presence of endothelium, and inhibition of NO production by N-nitro-L: -arginine-methyl ester completely blocked PDGF-dependent vascular relaxation. In addition, PDGF-dependent relaxation was completely abolished by inhibition of PI3K with wortmannin (100 nM). Furthermore, vessels from Akt1 heterozygotes showed normal relaxation after PDGF stimulation, whereas vessels from Akt1 knockout littermates did not respond to PDGF stimulation. Finally, administration of PDGF (5 ng/ml) significantly lowered blood pressure in Akt1 heterozygotes, whereas a blood pressure-lowering effect was not observed in Akt1 knockout littermates. These results suggest that Akt1 regulates blood pressure through regulation of vascular relaxation by eNOS phosphorylation and subsequent production of NO.
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Affiliation(s)
- Jung Min Ha
- MRC for Ischemic Tissue Regeneration and Department of Pharmacology, Pusan National University School of Medicine, Bumeo-ri, Mulgeum-eup, Yangsan-si, Kyungnam, Republic of Korea
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Ballas MS, Chachoua A. Rationale for targeting VEGF, FGF, and PDGF for the treatment of NSCLC. Onco Targets Ther 2011; 4:43-58. [PMID: 21691577 PMCID: PMC3116793 DOI: 10.2147/ott.s18155] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2011] [Indexed: 01/06/2023] Open
Abstract
Lung cancer remains a leading cause of death globally, with the most frequent type, nonsmall cell lung cancer (NSCLC), having a 5-year survival rate of less than 20%. While platinum-based doublet chemotherapy is currently first-line therapy for advanced disease, it is associated with only modest clinical benefits at the cost of significant toxicities. In an effort to overcome these limitations, recent research has focused on targeted therapies, with recently approved agents targeting the epidermal growth factor receptor and vascular endothelial growth factor (VEGF) signaling pathways. However, these agents (gefitinib, erlotinib, and bevacizumab) provide antitumor activity for only a small proportion of patients, and patients whose tumors respond inevitably develop resistance to treatment. As angiogenesis is a crucial step in tumor growth and metastasis, antiangiogenic treatments might be expected to have antitumor activity. Important targets for the development of novel antiangiogenic therapies include VEGF, fibroblast growth factor, platelet-derived growth factor, and their receptors. It is hypothesized that targeting multiple angiogenic pathways may not only improve antitumor activity but also reduce the risk of resistance. Several novel agents, such as BIBF 1120, sorafenib, sunitinib, and cediranib have shown promising preliminary activity and tolerability in Phase II studies, and results of ongoing Phase III randomized studies will be necessary to establish the potential place of these new therapies in the management of individual patients with NSCLC.
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Affiliation(s)
- Marc S Ballas
- Department of Medicine (Cancer Center), New York University Langone School of Medicine, New York, NY, USA
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Burger RA. Overview of anti-angiogenic agents in development for ovarian cancer. Gynecol Oncol 2011; 121:230-8. [PMID: 21215996 DOI: 10.1016/j.ygyno.2010.11.035] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2010] [Revised: 11/20/2010] [Accepted: 11/22/2010] [Indexed: 12/31/2022]
Abstract
OBJECTIVE To review the rationale for targeting the vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), and fibroblast growth factor (FGF) pathways for anti-angiogenic therapy in patients with ovarian cancer and to summarize the currently available data with agents that block these pathways. METHODS Relevant papers and studies were identified by searches conducted on Medline using the terms angiogenesis, ovarian cancer, VEGF, PDGF, FGF, receptor, kinase, and inhibitor alone or in combination as well as by searches by drug name and by review of abstracts presented at recent oncology meetings. RESULTS The VEGF pathway is considered to be the key driver of angiogenesis, but the PDGF and FGF pathways also play important roles and may contribute to resistance to VEGF-specific blockade. Each pathway may also promote tumorigenesis; tumor cell overexpression of these growth factors and their receptors have been detected in ovarian tumor specimens, suggesting that autocrine loops may lead to tumor growth and progression. Selective inhibitors of the VEGF pathway (e.g., bevacizumab and VEGF Trap) as well as VEGF/PDGF pathway inhibitors (e.g., sorafenib and sunitinib) and VEGF/PDGF/FGF pathway inhibitors (e.g., cediranib, pazopanib, and BIBF 1120) have shown single-agent activity in women with ovarian cancer in phase II trials. Response rates of up to 21% have been reported with several agents in patients with recurrent ovarian cancer. Phase III trials with many anti-angiogenic agents in the treatment of ovarian cancer are currently ongoing. CONCLUSIONS Anti-angiogenic agents may provide an improvement in the treatment of patients with recurrent ovarian cancer and may be useful when incorporated into first-line platinum/taxane therapy. It remains to be determined whether multitargeted agents will offer greater clinical benefit than specific VEGF pathway inhibitors.
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Affiliation(s)
- Robert A Burger
- Department of Surgical Oncology, Section of Gynecologic Oncology, Fox Chase Cancer Center, Philadelphia, PA 19111-2497, USA.
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Demidova-Rice TN, Geevarghese A, Herman IM. Bioactive peptides derived from vascular endothelial cell extracellular matrices promote microvascular morphogenesis and wound healing in vitro. Wound Repair Regen 2010; 19:59-70. [PMID: 21134032 DOI: 10.1111/j.1524-475x.2010.00642.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Studies in our laboratory indicate that collagenase from Clostridium histolyticum promotes endothelial cell and keratinocyte responses to injury in vitro and wound healing in vivo. We postulate that matrix degradation by Clostridial collagenase creates bioactive fragments that can stimulate cellular responses to injury and angiogenesis. To test this hypothesis, we performed limited digestion of defined capillary-endothelial-derived extracellular matrices using purified human or bacterial collagenases. Immunoprecipitation with antibodies recognizing collagens I, II, III, IV, and V, followed by mass spectrometry reveals the presence of unique fragments in bacterial, but not human-enzyme-digested matrix. Results show that there are several bioactive peptides liberated from Clostridial collagenase-treated matrices, which facilitate endothelial responses to injury, and accelerate microvascular remodeling in vitro. Fragments of collagen IV, fibrillin-1, tenascin X, and a novel peptide created by combining specific amino acids contained within fibrillin 1 and tenascin X each have profound proangiogenic properties. The peptides used at 10-100 nM increase rates of microvascular endothelial cell proliferation by up to 47% and in vitro angiogenesis by 200% when compared with serum-stimulated controls. Current studies are aimed at revealing the molecular mechanisms regulating peptide-induced wound healing while extending these in vitro observations using animal modeling.
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Affiliation(s)
- Tatiana N Demidova-Rice
- Graduate Program in Cellular and Molecular Physiology, Center for Innovations in Wound Healing Research, Sackler School of Graduate Biomedical Sciences, School of Medicine, Tufts University, Boston, Massachusetts 02111, USA
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Ranzato E, Boccafoschi F, Mazzucco L, Patrone M, Burlando B. Role of ERK1/2 in platelet lysate-driven endothelial cell repair. J Cell Biochem 2010; 110:783-93. [PMID: 20512938 DOI: 10.1002/jcb.22591] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Mechanisms of endothelial repair induced by a platelet lysate (PL) were studied on human (HuVEC, HMVEC-c) and non-human (PAOEC, bEnd5) endothelial cells. A first set of analyses on these cells showed that 20% (v/v) PL promotes scratch wound healing, with a maximum effect on HuVEC. Further analyses made on HuVEC showed that the ERK inhibitor PD98059 maximally inhibited the PL-induced endothelial repair, followed in order of importance by the calcium chelator BAPTA-AM, the PI3K inhibitor wortmannin and the p38 inhibitor SB203580. The PL exerted a chemotactic effect on HuVEC, which was abolished by all the above inhibitors, and induced a PD98059-sensitive increase of cell proliferation rate. Confocal calcium imaging of fluo-3-loaded HuVEC showed that PL was able to induce cytosolic free Ca(2+) oscillations, visible also in Ca(2+)-free medium, suggesting an involvement of Ins3P-dependent Ca(2+) release. Western blot analysis on scratch wounded HuVEC showed that PL induced no activation of p38, a transient activation of AKT, and a sustained activation of ERK1/2. The complex of data indicates that, although different signalling pathways are involved in PL-promoted endothelial repair, the process is chiefly under the control of ERK1/2.
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Affiliation(s)
- Elia Ranzato
- Department of Environment and Life Sciences, University of Piemonte Orientale Amedeo Avogadro, viale T Michel 11, 15121 Alessandria, Italy.
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Holmgren L. Potential Dual Roles of PDGF-B during Human Placental Blood Vessel Formation. ACTA ACUST UNITED AC 2009. [DOI: 10.3109/10623329309102693] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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25
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Yang QR, Zwijsen A, Slegers H, Berghe DV. Purification and Characterization of VEGFNPF Secreted by Human Retinal Pigment Epithelial Cells. ACTA ACUST UNITED AC 2009. [DOI: 10.3109/10623329409024636] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Khachigian LM, Chesterman CN. Platelet-derived Growth Factor and its Receptor: Structure and Roles in Normal Growth and Pathology. Platelets 2009; 4:304-15. [DOI: 10.3109/09537109309013233] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Abstract
Metastatic melanoma cells express a number of protein tyrosine kinases (PTKs) that are considered to be targets for imatinib. We conducted a phase II trial of imatinib in patients with metastatic melanoma expressing at least one of these PTKs. Twenty-one patients whose tumours expressed at least one PTK (c-kit, platelet-derived growth factor receptors, c-abl, or abl-related gene) were treated with 400 mg of imatinib twice daily. One patient with metastatic acral lentiginous melanoma, containing the highest c-kit expression among all patients, had dramatic improvement on positron emission tomographic scan at 6 weeks and had a partial response lasting 12.8 months. The responder had a substantial increase in tumour and endothelial cell apoptosis at 2 weeks of treatment. Imatinib was fairly well tolerated: no patient required treatment discontinuation because of toxicity. Fatigue and oedema were the only grade 3 or 4 toxicities that occurred in more than 10% of the patients. Imatinib at the studied dose had minimal clinical efficacy as a single-agent therapy for metastatic melanoma. However, based on the characteristics of the responding tumour in our study, clinical activity of imatinib, specifically in patients with melanoma with certain c-kit aberrations, should be examined.
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Craft RO, Rophael J, Morrison WA, Vashi AV, Mitchell GM, Penington AJ. Effect of local, long-term delivery of platelet-derived growth factor (PDGF) on injected fat graft survival in severe combined immunodeficient (SCID) mice. J Plast Reconstr Aesthet Surg 2008; 62:235-43. [PMID: 18178534 DOI: 10.1016/j.bjps.2007.11.017] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2007] [Accepted: 11/01/2007] [Indexed: 10/22/2022]
Abstract
SUMMARY BACKGROUND Autogenous fat injection is widely used for the correction of acquired and congenital soft tissue defects. However, the high absorption rate results in the need for over-correction of the defect and repeat procedures. We hypothesised that platelet-derived growth factor (PDGF), a potent mitogen and known stimulant for murine preadipocytes, would improve fat graft survival when concentrations were sustained with a gelatine microsphere delivery system. METHODS Abdominal fat was harvested from an otherwise healthy 43-year-old woman during a breast reconstruction. Prior to subdermal injection into severe combined immunodeficient (SCID) mice, the fat grafts were divided into 1-ml aliquots, mixed with microspheres bound to PDGF, free PDGF, or nothing depending on its experimental group, and weighed. The following experimental groups were thus created (minimum n=8 per group): (1) fat graft control, (2) fat graft with free PDGF, (3) fat graft with blank microspheres, and (4) fat graft with microspheres bound to PDGF. After 12 weeks, the fat xenografts were harvested for analysis of weight maintenance and histological and morphometric evaluation. RESULTS The addition of PDGF bound to gelatine microspheres was effective in improving xenograft weight maintenance (P=0.018) and preservation of adipose tissue architecture (P<0.0005) compared to controls at 3 months. The microspheres were completely absorbed at 12 weeks. CONCLUSIONS Sustained, local delivery of PDGF via a gelatine microsphere delivery system resulted in improved weight maintenance of the xenografts with greater preservation of adipose tissue architecture at 3 months compared to controls.
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Affiliation(s)
- Randall O Craft
- Bernard O'Brien Institute of Microsurgery, St. Vincent's Hospital, Fitzroy, Victoria, Australia
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29
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Kazlauskas A. Platelet-Derived Growth Factor. Angiogenesis 2008. [DOI: 10.1007/978-0-387-71518-6_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Que J, Lian Q, El Oakley RM, Lim B, Lim SK. PI3 K/Akt/mTOR-mediated translational control regulates proliferation and differentiation of lineage-restricted RoSH stem cell lines. J Mol Signal 2007; 2:9. [PMID: 17892597 PMCID: PMC2045085 DOI: 10.1186/1750-2187-2-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2007] [Accepted: 09/25/2007] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND We have previously derived highly similar lineage-restricted stem cell lines, RoSH and E-RoSH cell lines from mouse embryos and CD9hi SSEA-1- differentiated mouse embryonic stem cells, respectively. These cell lines are not pluripotent and differentiate readily into endothelial cells in vitro and in vivo. RESULTS We investigated the signaling pathway that maintains proliferation of these cells in an undifferentiated state, and demonstrate that PI3 K/Akt/mTOR, but not Raf/MEK/Erk, signaling in these cells was active during proliferation and was downregulated during endothelial differentiation. Inhibition of PI3 K/Akt/mTOR signaling, but not Raf/MEK/Erk, reduced proliferation and induced expression of endothelial specific proteins. During differentiation or inhibition of PI3 K/Akt/mTOR signaling, cyclinD2 transcript abundance in ribosome-enriched RNA but not in total RNA was reduced with a corresponding reduction in protein level. In contrast, transcript abundance of endothelial-specific genes e.g. Kdr, Tek and Pdgfralpha in ribosome-enriched RNA fraction was not reduced and their protein levels were increased. Together these observations suggested that translational control mediated by PI3K/Akt/mTOR signaling was critical in regulating proliferation and endothelial differentiation of lineage-restricted RoSH-like stem cell lines. CONCLUSION This study highlights translation regulation as a critical regulatory mechanism during proliferation and differentiation in stem cells.
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Affiliation(s)
- Jianwen Que
- Dept. of Surgery, National University of Singapore, Lower Kent Ridge Road, Singapore 117597
| | - Qizhou Lian
- Dept. of Surgery, National University of Singapore, Lower Kent Ridge Road, Singapore 117597
| | - Reida M El Oakley
- Dept. of Surgery, National University of Singapore, Lower Kent Ridge Road, Singapore 117597
| | - Bing Lim
- Genome Institute of Singapore, 60 Biopolis Street, Singapore 138672
- Beth Israel Deaconess Medical Center, Harvard Medical School, 4 Blackfan Circle, Boston, MA, USA 02115
| | - Sai-Kiang Lim
- Institute of Medical Biology, 11 Biopolis Street, Helios #02-02, Singapore 13866
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Lederle W, Stark HJ, Skobe M, Fusenig NE, Mueller MM. Platelet-derived growth factor-BB controls epithelial tumor phenotype by differential growth factor regulation in stromal cells. THE AMERICAN JOURNAL OF PATHOLOGY 2006; 169:1767-83. [PMID: 17071599 PMCID: PMC1780216 DOI: 10.2353/ajpath.2006.060120] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Platelet-derived growth factor (PDGF) stimulates tumor growth and progression by affecting tumor and stromal cells. In the HaCaT skin carcinogenesis model, transfection of immortal nontumorigenic and PDGF-receptor-negative HaCaT keratinocytes with PDGF-B induced formation of benign tumors. Here, we present potential mechanisms underlying this tumorigenic conversion. In vivo, persistent PDGF-B expression induced enhanced tumor cell proliferation but only transiently stimulated stromal cell proliferation and angiogenesis. In vitro and in vivo studies identified fibroblasts as PDGF target cells essential for mediating transient angiogenesis and persistent epithelial hyperproliferation. In fibroblast cultures, long-term PDGF-BB treatment caused an initial up-regulation of vascular endothelial growth factor (VEGF)-A, followed by a drastic VEGF down-regulation and myofibroblast differentiation. Accordingly, in HaCaT/PDGF-B transplants, initially enhanced VEGF expression by stromal fibroblasts was subsequently reduced, followed by down-regulation of angiogenesis, myofibroblast accumulation, and vessel maturation. The PDGF-induced, persistently increased expression of the hepatocyte growth factor by fibroblasts in vitro and in vivo was most probably responsible for enhanced epithelial cell proliferation and benign tumor formation. Thus, by paracrine stimulation of the stroma, PDGF-BB induced epithelial hyperproliferation, thereby promoting tumorigenicity, whereas the time-limited activation of the stroma followed by stromal maturation provides a possible explanation for the benign tumor phenotype.
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Affiliation(s)
- Wiltrud Lederle
- Tumor and Microenvironment Group, German Cancer Research Center, Heidelberg, Germany
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Kitadai Y, Sasaki T, Kuwai T, Nakamura T, Bucana CD, Hamilton SR, Fidler IJ. Expression of activated platelet-derived growth factor receptor in stromal cells of human colon carcinomas is associated with metastatic potential. Int J Cancer 2006; 119:2567-74. [PMID: 16988946 DOI: 10.1002/ijc.22229] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Platelet-derived growth factor receptor (PDGF-R) expression has been reported in a variety of cancers, including colorectal, breast, lung, ovarian and pancreatic cancers, but the role of PDGF-R expression in the development and progression of colon carcinoma has not yet been elucidated. The purpose of this study was to examine the expression of PDGF and PDGF-R in human colon carcinomas. The expression of PDGF, PDGF-R and phosphorylated PDGF-R (p-PDGF-R) was examined by immunofluorescence in 12 surgical specimens of colon carcinoma and in human colon carcinoma cells growing in the subcutis (ectopic site) and the cecal wall (orthotopic site) of nude mice. In most surgical specimens, tumor cells expressed PDGF-A and -B subunits, without corresponding levels of PDGF-Ralpha and PDGF-Rbeta. PDGF-Rbeta was predominantly expressed by tumor-associated stromal cells and pericytes of tumor vasculature. The expression of PDGF-Rbeta in the stroma was associated with advanced stage disease. Under culture conditions, human colon carcinoma cell lines expressed PDGF-A and -B, but not PDGF-R. In orthotopic tumors, the KM12 cells (Duke's stage B) expressed PDGF-A and -B, but PDGF-Rbeta was expressed only by stromal cells and pericytes in the tumor vasculature. This expression of PDGF-Rbeta by stromal cells and pericytes was higher in tumors growing at the orthotopic site than in those at the ectopic site. The expression of PDGF-Rbeta in the stroma was higher in highly metastatic KM12SM tumors than in low metastatic KM12C tumors. In conclusion, the expression of PDGF-Rbeta in stromal cells is influenced by the organ-specific microenvironment and is associated with metastatic potential.
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Affiliation(s)
- Yasuhiko Kitadai
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77230-1429, USA
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Lepin EJ, Zhang Q, Zhang X, Jindra PT, Hong LS, Ayele P, Peralta MVP, Gjertson DW, Kobashigawa JA, Wallace WD, Fishbein MC, Reed EF. Phosphorylated S6 ribosomal protein: a novel biomarker of antibody-mediated rejection in heart allografts. Am J Transplant 2006; 6:1560-71. [PMID: 16827856 DOI: 10.1111/j.1600-6143.2006.01355.x] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
We tested the hypothesis that phosphorylation of S6 ribosomal protein (S6RP), a downstream target of the PI3K/Akt/mTOR pathway, is a biomarker of antibody-mediated rejection (AMR) in heart allografts. Primary cultures of human aortic and microvascular endothelial cells (EC) were treated with anti-HLA class I and class II antibodies (Ab) and cell lysates were studied for phosphorylation of S6 ribosmal protein at Serine235/236 (p-S6RP). Treatment of cultured EC with anti-class I and class II Ab stimulated S6RP phosphorylation. Immunohistochemical techniques were used to detect the level of p-S6RP in endomyocardial biopsies (n = 131) from 46 heart transplant recipients and the results were correlated with histopathological diagnosis of rejection, C4d staining, production of posttransplant anti-HLA Ab and clinical outcome. Increased phosphorylation of S6RP in endomyocardial biopsies was significantly associated with the diagnosis of AMR (p < 0.0001). No significant association between acute cellular rejection (ACR) and p-S6RP was observed. C4d staining was positively associated with both AMR and p-S6RP. Posttransplant anti-HLA class II Ab production was also significantly associated with a positive p-S6RP status in cardiac biopsies. These results indicate that p-S6RP is a useful biomarker for the diagnosis of AMR.
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Affiliation(s)
- E J Lepin
- UCLA Immunogenetics Center, David Geffen School of Medicine, UCLA, Los Angeles, California, USA
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Goldstein LJ, Chen H, Bauer RJ, Bauer SM, Velazquez OC. Normal human fibroblasts enable melanoma cells to induce angiogenesis in type I collagen. Surgery 2005; 138:439-49. [PMID: 16213896 DOI: 10.1016/j.surg.2005.06.031] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2005] [Revised: 06/22/2005] [Accepted: 06/24/2005] [Indexed: 01/22/2023]
Abstract
BACKGROUND We previously reported that fibroblasts induce human microvascular endothelial cells (HMVECs) to differentiate from monolayer to capillarylike morphology. We now test the hypothesis that fibroblasts modulate angiogenesis in melanoma cells. METHODS We tested 12 human melanoma lines (2 radial growth phase (RGP), 3 vertical growth phase (VGP), and 7 metastatic (MM)) for ability to induce HMVECs to invade/migrate into collagen and form capillarylike networks. HMVEC monolayers were overlaid with 3-dimensional collagen gels embedded with melanoma cells alone (M), fibroblasts alone (F), or a 1:1 mixture of the 2 cells (M+F). After 5 days, gels were removed, fixed, and HMVEC networks were quantified by von Willebrand's factor (vWF) immunofluorescence. The influence of soluble factors on HMVEC invasion/migration into collagen was assessed with the use of acellular 3-D collagen gels overlaid on HMVEC monolayers, cultured with conditioned media (CM) derived from monolayers of M, F, or M+F. Angiogenic growth factors involved in the observed invasion/migration were identified with the use of a RayBio Cytokine Antibody Array (RayBiotech, Norcross, Ga). RESULTS Cell line-specific variability in melanoma-supported angiogenesis was observed only when in combination with fibroblasts (analysis of variance [ANOVA], P < .01). Melanoma plus fibroblasts uniformly resulted in a significantly higher angiogenic response than melanoma alone (P < .05). One vertical growth phase and one metastatic melanoma line, while weakly angiogenic alone, induced significantly higher angiogenesis than either fibroblast or melanoma alone (P < .05) when combined with fibroblasts. CM from M or M+F induced significantly less HMVEC invasion/migration into collagen than CM from fibroblasts alone. Interleukin 8, monocyte chemotactic protein-1, and tissue inhibitor of metalloproteinase-2 were identified as significantly elevated in the media derived from M+F cultures, compared with either cell type alone. CONCLUSION To our knowledge, this is the first report demonstrating that melanoma-supported angiogenesis in collagen is more significantly influenced by normal skin-derived fibroblasts than by the intrinsic biology of the melanoma cell type. Interleukin 8, monocyte chemotactic protein-1, and tissue inhibitor of metalloproteinase-2 are implicated as potential paracrine factors regulating this observed effect.
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Affiliation(s)
- Lee J Goldstein
- Hospital of the University of Pennsylvania, Philadelphia 19104, USA
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Li X, Tjwa M, Moons L, Fons P, Noel A, Ny A, Zhou JM, Lennartsson J, Li H, Luttun A, Pontén A, Devy L, Bouché A, Oh H, Manderveld A, Blacher S, Communi D, Savi P, Bono F, Dewerchin M, Foidart JM, Autiero M, Herbert JM, Collen D, Heldin CH, Eriksson U, Carmeliet P. Revascularization of ischemic tissues by PDGF-CC via effects on endothelial cells and their progenitors. J Clin Invest 2005; 115:118-27. [PMID: 15630451 PMCID: PMC535797 DOI: 10.1172/jci19189] [Citation(s) in RCA: 113] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2003] [Accepted: 11/09/2004] [Indexed: 12/14/2022] Open
Abstract
The angiogenic mechanism and therapeutic potential of PDGF-CC, a recently discovered member of the VEGF/PDGF superfamily, remain incompletely characterized. Here we report that PDGF-CC mobilized endothelial progenitor cells in ischemic conditions; induced differentiation of bone marrow cells into ECs; and stimulated migration of ECs. Furthermore, PDGF-CC induced the differentiation of bone marrow cells into smooth muscle cells and stimulated their growth during vessel sprouting. Moreover, delivery of PDGF-CC enhanced postischemic revascularization of the heart and limb. Modulating the activity of PDGF-CC may provide novel opportunities for treating ischemic diseases.
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Affiliation(s)
- Xuri Li
- The Center for Transgene Technology and Gene Therapy, Flanders Interuniversitary Institute for Biotechnology (VIB), University of Leuven, Leuven, Belgium
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Esmaeli B, Prieto VG, Gonnering R, Hawes MJ, Diba R, Saadati HG, Shepler TR, Karcioglu Z. Growth factor receptor expression in orbital lymphangioma: possible therapeutic implications. Orbit 2004; 23:263-9. [PMID: 15590529 DOI: 10.1080/01676830590889875] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
Abstract
OBJECTIVE To examine the expression of molecules targeted by imatinib mesylate (STI571;Gleevec) and epidermal growth factor receptor (EGFR) inhibitors in orbital lymphangiomas. DESIGN Retrospective observational case series. PARTICIPANTS Six patients with orbital lymphangioma treated at four institutions between March 2000 and December 2002. METHODS Tissue specimens and medical records from six patients were collected. Immunohistochemical analysis was performed using antibodies against c-kit and platelet-derived growth factor receptor (PDGFR) alpha and beta and EGFR tyrosine kinase.
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Affiliation(s)
- Bita Esmaeli
- Ophthalmology Section, Department of Plastic Surgery, University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030-4009, USA.
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Langley RR, Fan D, Tsan RZ, Rebhun R, He J, Kim SJ, Fidler IJ. Activation of the platelet-derived growth factor-receptor enhances survival of murine bone endothelial cells. Cancer Res 2004; 64:3727-30. [PMID: 15172974 DOI: 10.1158/0008-5472.can-03-3863] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The activation of the microvascular endothelial cell platelet-derived growth factor (PDGF) receptor (PDGF-R) by PDGF has been implicated in neoplastic angiogenesis. Here, we established cultures of murine bone microvascular endothelial cells and examined their response to stimulation with PDGF BB ligand and to blockade of PDGF-R signaling with the tyrosine kinase inhibitor STI571 (Gleevec). The addition of STI571 to cultures of bone endothelial cells blocked PDGF BB-induced phosphorylation in a dose-dependent manner and completely abrogated the activation of downstream targets Akt and ERK1/2. Coadministration of STI571 and Taxol also induced the activation of procaspase-3 and significant apoptosis. These data suggest that phosphorylation of PDGF-R stimulates survival pathways in bone endothelial cells and that by selectively inhibiting PDGF-R signaling with STI571, the cells are rendered sensitive to Taxol treatment. The therapeutic combination of STI571 and Taxol may be a powerful tool for targeting tumor-associated endothelial cells in the skeletal compartment.
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Affiliation(s)
- Robert R Langley
- Department of Cancer Biology, The University of Texas M D Anderson Cancer Center, Houston, Texas 77030, USA
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38
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Apte SM, Bucana CD, Killion JJ, Gershenson DM, Fidler IJ. Expression of platelet-derived growth factor and activated receptor in clinical specimens of epithelial ovarian cancer and ovarian carcinoma cell lines. Gynecol Oncol 2004; 93:78-86. [PMID: 15047217 DOI: 10.1016/j.ygyno.2003.12.041] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2003] [Indexed: 01/02/2023]
Abstract
OBJECTIVES We determined the expression of platelet-derived growth factor (PDGF), PDGF-receptor (PDGF-R), and phosphorylated PDGF-R (p-PDGF-R) on tumor cells and tumor-associated endothelial cells in clinical specimens of human ovarian carcinoma and human ovarian cancer cells growing in culture and in the peritoneal cavity of nude mice. METHODS Ten specimens of high-grade serous ovarian carcinoma were analyzed using immunohistochemistry (IHC). IHC was used to detect ligand and receptor expression in the human ovarian cancer cells from Hey A8 and SKOV3ip1 growing in culture. Cells from these lines were also implanted orthotopically into the peritoneal cavity of nude mice. IHC was used to determine ligand and receptor expression in tumors that formed in the peritoneal cavity. RESULTS All 10 evaluable samples expressed both PDGF AA and BB on tumor cells. Tumor cells were positive for PDGF-Ralpha in 10/10 samples, PDGF-Rbeta in 8/10 samples, p-PDGF-Ralpha in 6/10 samples, and p-PDGF-Rbeta in 4/10 samples. p-PDGF-Ralpha was positive in 4/10 tumor-associated endothelial cell samples and p-PDGF-Rbeta was positive in 3/10 samples. Human ovarian cancer cells expressed PDGF, PDGF-R, and p-PDGF-R when growing in culture or in the peritoneal cavity of nude mice. PDGF-R and p-PDGF-R were also present on tumor-associated endothelial cells as demonstrated by simultaneous staining with CD31 antibody. CONCLUSIONS PDGF and the corresponding receptors were expressed in autochthonous human ovarian cancer lesions on both tumor cells and tumor-associated endothelial cells. The ligand and receptor were also present on Hey A8 and SKOV3ip1 human ovarian cancer cells growing in vitro and in the peritoneal cavity of nude mice.
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Affiliation(s)
- Sachin M Apte
- Department of Gynecologic Oncology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA
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Apte SM, Fan D, Killion JJ, Fidler IJ. Targeting the Platelet-Derived Growth Factor Receptor in Antivascular Therapy for Human Ovarian Carcinoma. Clin Cancer Res 2004; 10:897-908. [PMID: 14871965 DOI: 10.1158/1078-0432.ccr-1151-3] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE We sought to determine whether blockade of platelet-derived growth factor receptor (PDGF-R) activation by oral administration of a PDGF-R tyrosine kinase inhibitor (STI571) alone or in combination with i.p. paclitaxel can inhibit the progression of tumors caused by human ovarian carcinoma cells growing in the peritoneal cavity of female nude mice. EXPERIMENTAL DESIGN In several different experiments, paclitaxel-sensitive and paclitaxel-resistant metastatic human ovarian carcinoma cells were injected into the peritoneal cavity of nude mice. Seven days later, groups (n = 10) of mice began receiving a control treatment, STI571 alone, paclitaxel alone, or a combination of STI571 and paclitaxel. The mice were necropsied after 45 days of treatment. RESULTS Treatment with combination therapy significantly reduced tumor weight (relative to control or single-agent therapy) in all three human ovarian cancer cell lines. Immunohistochemical analyses revealed that PDGF-R activation was blocked by STI571 administered alone or in combination with paclitaxel. Tumor-associated endothelial cells expressed both PDGF-R and phosphorylated PDGF-R. In mice receiving combination therapy, tumor-associated endothelial cells underwent apoptosis, leading to decreases in microvessel density and tumor cell proliferation relative to control and single-agent therapy. CONCLUSIONS These results show that administration of a PDGF-R tyrosine kinase inhibitor in combination with paclitaxel impairs the progression of ovarian cancer in the peritoneal cavity of nude mice, in part, by blockade of PDGF, an endothelial cell survival factor, which results in the increased apoptosis of tumor-associated endothelial cells.
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Affiliation(s)
- Sachin M Apte
- Department of Cancer Biology, The University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA
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Boguslawski G, McGlynn PW, Harvey KA, Kovala AT. SU1498, an inhibitor of vascular endothelial growth factor receptor 2, causes accumulation of phosphorylated ERK kinases and inhibits their activity in vivo and in vitro. J Biol Chem 2003; 279:5716-24. [PMID: 14625306 DOI: 10.1074/jbc.m308625200] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
SU1498, an inhibitor of vascular endothelial growth factor receptor 2, has been used successfully to study the physiological manifestations of receptor functions. Here we report that in addition to its anti-receptor activity, SU1498 stimulates accumulation of phosphorylated ERKs in human umbilical vein endothelial cells and in human aortic endothelial cells in a manner that is dependent on the functioning of the upstream components of the MAPK pathway, B-Raf, and MEK kinases. The enhanced accumulation of phospho-ERKs is observed only in cells that have been stimulated with sphingosine 1-phosphate or protein growth factors; SU1498 by itself is ineffective. We show that the inhibitor acts by blocking the kinase activity of phospho-ERK both in a direct assay and in immunoprecipitates from cells treated with the compound. The data reveal a novel and unique way in which MAPK signaling pathway may be blocked in human endothelial cells.
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Affiliation(s)
- George Boguslawski
- Methodist Research Institute, Clarian Health Partners, Indianapolis, Indiana 46202, USA
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Dudley A, Gilbert RE, Thomas D, Cox A, Price JT, Best J, Jenkins A. STI-571 inhibits in vitro angiogenesis. Biochem Biophys Res Commun 2003; 310:135-42. [PMID: 14511660 DOI: 10.1016/j.bbrc.2003.08.129] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Compounds that block angiogenesis are effective in the treatment of certain cancers and other angiogenesis-related diseases. Many of these compounds specifically target the rapidly proliferating and migrating endothelial cell. However, angiogenesis is a multi-faceted process involving heterotypic interactions between various cell types. For example, PDGFBB is an important cytokine secreted by endothelial cells that attracts smooth muscle cells to surround and stabilize a nascent vessel. Therefore, we hypothesized that STI-571, a tyrosine kinase inhibitor with PDGFbeta receptor activity, would inhibit angiogenesis through an anti-migratory effect on smooth muscle cells. We demonstrate that STI-571 completely inhibits in vitro angiogenesis in fibrinogen-embedded mouse aorta. Furthermore, this angiostatic property was due mainly to an anti-migratory and anti-proliferative effect upon smooth muscle cells. These data suggest that STI-571, in addition to its efficacy in the treatment of certain cancers, may also prove to be clinically useful in diseases characterized by unregulated angiogenesis.
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Affiliation(s)
- Andrew Dudley
- Department of Medicine, St Vincent's Hospital, University of Melbourne, Australia.
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Uhl E, Rösken F, Sirsjö A, Messmer K. Influence of platelet-derived growth factor on microcirculation during normal and impaired wound healing. Wound Repair Regen 2003; 11:361-7. [PMID: 12950640 DOI: 10.1046/j.1524-475x.2003.11508.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The aim of the current study was to evaluate the influence of platelet-derived growth factor (PDGF) on skin microcirculation during normal and impaired wound healing. Secondary healing wounds were created on the ears of hairless mice and treated once with 3 microg of PDGF-BB immediately after wound creation. Intravital fluorescence microscopy was used to quantify reepithelialization, revascularization, vessel diameters, vascular permeability, and leukocyte-endothelium interactions up to 24 days after wound creation. Microvascular perfusion was assessed by laser Doppler flowmetry. Wound healing was studied in normal (n = 15) and ischemic skin tissue (n = 15) as well as in mice (n = 17) rendered hyperglycemic by an intravenous injection of streptozotocin 7 days prior to wound creation. Treatment with PDGF accelerated reepithelialization and reduced the time for complete wound closure in ischemic skin from 14.9 +/- 2.5 (control) to 12.3 +/- 1.8 days (p < 0.03), and in hyperglycemic animals from 15.0 +/- 2.4 (control) to 12.0 +/- 3.0 days (p < 0.04). Revascularization of these wounds was also significantly enhanced after PDFG application. No other parameters were influenced by the treatment. Normal wound healing was not affected. This study confirms the positive influence of PDGF on wound healing under pathophysiological conditions. The effects in this model seem to be primarily due to the mitogenic potency of PDGF on keratinocytes and endothelial cells. A significant effect on leukocyte activation during the inflammatory process was not observed.
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Affiliation(s)
- Eberhard Uhl
- Department of Neurosurgery, Ludwig-Maximilians-University, Grosshadern University Hospital, Marchioninistrasse 15, D-81377 Munich, Germany.
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Affiliation(s)
- Roy S Herbst
- University of Texas M.D. Anderson Cancer Center, Houston, TX, USA
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Vinores SA, Seo MS, Derevjanik NL, Campochiaro PA. Photoreceptor-specific overexpression of platelet-derived growth factor induces proliferation of endothelial cells, pericytes, and glial cells and aberrant vascular development: an ultrastructural and immunocytochemical study. BRAIN RESEARCH. DEVELOPMENTAL BRAIN RESEARCH 2003; 140:169-83. [PMID: 12586423 DOI: 10.1016/s0165-3806(02)00581-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Platelet-derived growth factor (PDGF) is necessary for the normal development of the retinal vasculature and its overexpression is likely to contribute to proliferative retinal disorders, such as proliferative vitreoretinopathy. Transgenic mice that overexpress PDGF-B in the photoreceptors (rho/PDGF-B mice) develop traction retinal detachment. In the present study, a detailed histopathological analysis was performed in rho/PDGF-B mice. In these transgenic mice, endothelial cells, pericytes, and glial cells begin to proliferate at postnatal day 7 (P7). All three cell types increase in numbers, forming a highly vascularized cell mass, which reaches a maximum thickness at P14. Cords of endothelial cells and glia invade the retina and exert traction, generating retinal folds; however, the deep capillary bed never forms. Griffonia simplicifolia isolectin B4 (GSA)-positive endothelial cells form tubes and penetrate the retina to the level of the outer plexiform layer, but they never interconnect to form the deep capillary bed. The vessels within the cell mass are patent, but have a very immature morphology. They often are thin-walled with fenestrations. Pericytes and glial cells are usually found in clusters and are not associated with the abnormal vessels. The lack of this association may account for the failure to form a mature vasculature.
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Affiliation(s)
- Stanley A Vinores
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD 21287-9289, USA.
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Cao R, Bråkenhielm E, Li X, Pietras K, Widenfalk J, Ostman A, Eriksson U, Cao Y. Angiogenesis stimulated by PDGF-CC, a novel member in the PDGF family, involves activation of PDGFR-alphaalpha and -alphabeta receptors. FASEB J 2002; 16:1575-83. [PMID: 12374780 DOI: 10.1096/fj.02-0319com] [Citation(s) in RCA: 175] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
A newly discovered PDGF isoform, PDGF-CC, is expressed in actively angiogenic tissues such as placenta, some embryonic tissues, and tumors. We test the possibility that PDGF-CC promotes angiogenesis in vivo. The core domain (mature form) of human PDGF-CC is sufficiently potent to stimulate neovascularization in the mouse cornea. The corneal angiogenic response induced by PDGF-CC is robust although the area of neovascularization is smaller than those of FGF-2- and VEGF-stimulated angiogenesis. Similarly, PDGF-BB and PDGF-AB induce angiogenic responses virtually indistinguishable from PDGF-CC-stimulated vessels. In contrast, PDGF-AA displays only a weak angiogenic response in the mouse cornea. Although there was no significant difference in incorporation of mural cells to the newly formed blood vessels induced by PDGF-BB and -CC, the percentage of mural cell positive vessels induced by PDGF-AA was greater than those induced by FGF-2, PDGF-BB, and PDGF-CC. In the developing chick embryo, PDGF-CC induced branch sprouts from established blood vessels. In PDGF receptor-transfected endothelial cells, PDGF-CC activated the PDGF receptor alpha subunit (PDGFR-alpha). PDGF-CC, but not PDGF-AA, was able to activate PDGFR-beta receptor in endothelial cells that coexpress both alpha and beta forms of receptors. Thus, the PDGF-CC-mediated angiogenic response is most likely transduced by PDGF-alphaalpha and -alphabeta receptors. These data demonstrate that the PDGF family is a complex and important group of proangiogenic factors.
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MESH Headings
- Allantois/blood supply
- Allantois/drug effects
- Animals
- Blood Vessels/drug effects
- Blood Vessels/metabolism
- Chick Embryo
- Chorion/blood supply
- Chorion/drug effects
- Cornea/blood supply
- Cornea/drug effects
- Cornea/metabolism
- Endothelial Growth Factors/pharmacology
- Endothelium, Vascular/cytology
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Gene Expression
- Humans
- Immunohistochemistry
- Intercellular Signaling Peptides and Proteins/pharmacology
- Lymphokines/pharmacology
- Male
- Mice
- Mice, Inbred C57BL
- Neovascularization, Pathologic/chemically induced
- Neovascularization, Pathologic/metabolism
- Phosphorylation/drug effects
- Platelet Endothelial Cell Adhesion Molecule-1/analysis
- Platelet-Derived Growth Factor/metabolism
- Platelet-Derived Growth Factor/pharmacology
- Protein Isoforms/genetics
- Protein Isoforms/metabolism
- RNA, Messenger/drug effects
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Receptor, Platelet-Derived Growth Factor alpha/genetics
- Receptor, Platelet-Derived Growth Factor alpha/metabolism
- Tyrosine/metabolism
- Vascular Endothelial Growth Factor A
- Vascular Endothelial Growth Factors
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Affiliation(s)
- Renhai Cao
- Microbiology and Tumor Biology Center, Karolinska Institute, S-171 77 Stockholm, Sweden
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46
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Dührsen U, Martinez T, Vohwinkel G, Ergün S, Sun L, McMahon G, Dürig J, Hossfeld DK, Fiedler W. Effects of vascular endothelial and platelet-derived growth factor receptor inhibitors on long-term cultures from normal human bone marrow. Growth Factors 2001; 19:1-17. [PMID: 11678206 DOI: 10.3109/08977190109001072] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Endothelial cells and fibroblasts are important constituents of the haemopoietic microenvironment. Growth and function of these cells are controlled by a variety of cytokines, including vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF). We analysed the effects of novel tyrosine kinase inhibitors targeting the VEGF and PDGF receptors (compounds SU5614 and SU5768) on the performance of long-term cultures from normal human bone marrow. In developing cultures, the inhibitors induced a dose-dependent reduction in stromal fibroblasts, macrophages and endothelial cells with a concomitant decrease in blood cell production and an increase in fat cells. For SU5614, the concentration inhibiting stroma formation by 50% (IC50) was 123nM, and the IC50 for haemopoietic colony forming cell output was 186 nM. For SU5768, the respective values were 871 nM and 331 nM. Changes in stroma composition and inhibition of haemopoietic cell production were also demonstrable after delayed addition of the inhibitors to established cultures. By contrast, haemopoietic colony formation in clonogenic agar cultures was unimpaired (IC50 not reached at 100 microM). Immunofluorescence studies and time course analyses suggested that the primary effect of the inhibitors was interference with the proliferation and function of fibroblasts and endothelial cells which in turn resulted in decreased haemopoiesis and increased adipogenesis. This was associated with decreased levels in conditioned media of granulocyte-macrophage colony-stimulating factor, interleukin-6 and leptin. VEGF and PDGF may play a hitherto underestimated role in the control of blood cell formation. VEGF/PDGF receptor inhibitors may have therapeutic potential in stroma diseases such as myelofibrosis. Since they weaken the stimulatory signals provided by the microenvironment, they may also be of value in the treatment of leukaemia and other neoplastic bone marrow diseases.
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Affiliation(s)
- U Dührsen
- Zentrum für Innere Medizin, Abteilung für Hämatologie, Universitätsklinikum Essen, Germany.
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47
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Pelletier L, Regnard J, Fellmann D, Charbord P. An in vitro model for the study of human bone marrow angiogenesis: role of hematopoietic cytokines. J Transl Med 2000; 80:501-11. [PMID: 10780667 DOI: 10.1038/labinvest.3780056] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
This study describes a human bone marrow endothelial cell culture in which endothelial cells are organized into capillary tubes. These endothelial cells were positive for von Willebrand Factor, expressed CD34, CD31, and L-fucose residues, took up acetylated low-density lipoproteins, contained Weibel-Palade bodies, and were ensheathed in a basal lamina (which included laminin beta1, EDa+ and EDb+ fibronectin, and collagen type iv). Pericytes expressing alpha-smooth muscle (alpha-SM) actin were spatially associated with the capillary tubes and there was a highly significant correlation between the number of capillary tubes and pericytes. In this model, basal angiogenesis was found to be vascular endothelial growth factor (VEGF)-dependent, because neutralization of endogenous VEGF induced a dramatic regression in the number of tubes. However, the presence of alpha-SM actin-expressing pericytes in the linings of endothelial tubes partially prevented the VEGF-neutralized tube regression. We also observed that nitric oxide production contributed to basal angiogenesis and that upregulation of nitric oxide increased the number of tubes. Tube numbers also decreased when antibodies neutralizing the integrin alphavbeta5 were applied to the cultures. Moreover, addition of any of the hematopoietic cytokines, erythropoietin, stem cell factor, granulocytic colony stimulating factor, or granulomonocytic colony stimulating factor induced a highly significant increase in tube formation. When erythropoietin and granulocytic colony stimulating factor were added, this increase was larger than the maximum increase observed with VEGF. Thus, we have described an in vitro model for human bone marrow angiogenesis in which pericytes and basal lamina matrix were associated with endothelial cells and formed fully organized capillary tubes. In this model, cytokines known to regulate hematopoiesis also seemed to be mediators of angiogenesis. This culture system may therefore prove to be a valuable tool for the study of hematopoietic cytokines on angiogenesis.
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Affiliation(s)
- L Pelletier
- Institut d'Etude et de Transfert de Gènes, Besancon, France.
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48
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Abstract
The most essential kinases involved in cell membrane receptor activation, signal transduction and cell cycle control or programmed cell death and their interconnections are reviewed. In tumours, the genes of many of those kinases are mutated or amplified or the proteins are overexpressed. The use of key kinases offers the possibility to screen in vitro for synthetic small molecule kinase inhibitors. In view of the many interconnections of cellular kinases, their role in preventing or inducing programmed cell death and the possibility that a considerable number of signal transducing proteins are still unknown, cellular test systems are recommended in which the respective key kinase or one of its main partner molecules are overexpressed.
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Affiliation(s)
- H H Sedlacek
- Aventis Pharma Deutschland GmbH, Central Biotechnology, Marburg, Germany.
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49
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Abstract
Platelet-derived growth factor (PDGF) is a major mitogen for connective tissue cells and certain other cell types. It is a dimeric molecule consisting of disulfide-bonded, structurally similar A- and B-polypeptide chains, which combine to homo- and heterodimers. The PDGF isoforms exert their cellular effects by binding to and activating two structurally related protein tyrosine kinase receptors, denoted the alpha-receptor and the beta-receptor. Activation of PDGF receptors leads to stimulation of cell growth, but also to changes in cell shape and motility; PDGF induces reorganization of the actin filament system and stimulates chemotaxis, i.e., a directed cell movement toward a gradient of PDGF. In vivo, PDGF has important roles during the embryonic development as well as during wound healing. Moreover, overactivity of PDGF has been implicated in several pathological conditions. The sis oncogene of simian sarcoma virus (SSV) is related to the B-chain of PDGF, and SSV transformation involves autocrine stimulation by a PDGF-like molecule. Similarly, overproduction of PDGF may be involved in autocrine and paracrine growth stimulation of human tumors. Overactivity of PDGF has, in addition, been implicated in nonmalignant conditions characterized by an increased cell proliferation, such as atherosclerosis and fibrotic conditions. This review discusses structural and functional properties of PDGF and PDGF receptors, the mechanism whereby PDGF exerts its cellular effects, and the role of PDGF in normal and diseased tissues.
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Affiliation(s)
- C H Heldin
- Ludwig Institute for Cancer Research, Biomedical Center, and Department of Pathology, University Hospital, Uppsala, Sweden.
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Zidovetzki R, Wang JL, Kim JA, Chen P, Fisher M, Hofman FM. Endothelin-1 enhances plasminogen activator inhibitor-1 production by human brain endothelial cells via protein kinase C-dependent pathway. Arterioscler Thromb Vasc Biol 1999; 19:1768-75. [PMID: 10397697 DOI: 10.1161/01.atv.19.7.1768] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The effects of endothelin-1 (ET-1) on the production of plasminogen activator inhibitor 1 (PAI-1) and tissue plasminogen activator (t-PA) by human brain-derived endothelial cells in culture were studied. At 100 nmol/L, ET-1 increased PAI-1 production by 88+/-6% within 72 hours, and increased PAI-1 mRNA expression within 1 hour of stimulation; there was no significant effect on t-PA production. PAI-1 activity was also examined and found to increase with ET-1 treatment. Suboptimal concentrations of ET-1 and tumor necrosis factor-alpha (TNF-alpha) acted synergistically to increase PAI-1 production. ET-1 activated protein kinase C and cAMP-dependent protein kinase pathways within 3 to 5 minutes of treatment, with the peak at 10 minutes. Activation of protein kinase C by phorbol-12-myristate-13-acetate (PMA) resulted in increased PAI-1 production, whereas activation of the cAMP-dependent protein kinase by forskolin or dibutyryl cAMP (dBu-cAMP) significantly decreased PAI-1 production. However, simultaneous activation of protein kinase C by PMA and cAMP-dependent protein kinase by dBu-cAMP only slightly attenuated PMA-induced PAI-1 increase. Inhibition of protein kinase C by GF-109213X abolished the effects of ET-1. These results demonstrate that ET-1 and TNF-alpha function synergistically to induce procoagulant activity of brain endothelial cells in a process that involves a protein kinase C-dependent pathway.
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Affiliation(s)
- R Zidovetzki
- Departments of Biology and Neuroscience, University of California, Riverside, CA, USA
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