419 results on '"Tobelem, G."'
Search Results
102. Heparin stimulates fibroblasts growth induced by platelet derived growth factor
- Author
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DUPUY, E, primary, ROHRLICH, P, additional, and TOBELEM, G, additional
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- 1988
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103. Comparison of von Willebrand Disease and Bernard-Soulier Syndrome
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Caen, J. P, additional, Michel, H, additional, Sultan, Y, additional, Tobelem, G, additional, Nurden, A. T, additional, and Levy-Toledano, S, additional
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- 1977
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104. Heparin degradation in the endothelial cells
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Barzu, T., primary, van Rijn, J.L.M.L., additional, Petitou, M., additional, Tobelem, G., additional, and Caen, J.P., additional
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- 1987
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105. L'héparine hier et aujourd'hui
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Molho, P, primary and Tobelem, G, additional
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- 1985
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106. The lupus anticoagulant and its role in thrombosis
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Tobelem, G., primary, Cariou, R., additional, and Camez, A., additional
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- 1987
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107. 1?, 25 ? Dihydroxyvitamin D modulates the growth of 3T3 cells and human skin fibroblasts stimulated by platelet-derived growth factor
- Author
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DOSQUETBERNARD, C, primary, WILHELM, F, additional, LOMRI, N, additional, TOBELEM, G, additional, and CAEN, J, additional
- Published
- 1986
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- View/download PDF
108. Binding of heparin to human microvascular endothelial cells and the effect on proliferation
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BIKFALVI, A, primary, DUPUY, E, additional, RUAN, C, additional, TOBELEM, G, additional, LESECHE, G, additional, and CAEN, J, additional
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- 1988
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- View/download PDF
109. The potentiating effect of platelet on plasminogen activation by tissue plasminogen activator
- Author
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Deguchi, K., primary, Murashima, S., additional, Shirakawa, S., additional, Soria, C., additional, Soria, J., additional, Dunn, F., additional, and Tobelem, G., additional
- Published
- 1985
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- View/download PDF
110. TYPE IIB VON WILLEBRAND DISEASE WITH CHRONIC THROMBOCYTOPENIA : BENEFICIAL EFFECT OF CRYOPRECIPITATE SUPERNATANT INFUSION ON PLATELET COUNT AND BLEEDING
- Author
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Derlon, A, additional, Le Querrec, A, additional, Lebrun, E, additional, Tobelem, G, additional, and Thomas, M, additional
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- 1987
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111. HEPARIN STIMULATES FIBROBLAST GROWTH INDUCED BY PDGF
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Dupuy, E, additional, Rohrlich, P S, additional, and Tobelem, G, additional
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- 1987
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112. New approach to determination of specific functions of platelet membrane sites
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TOBELEM, G., primary, LEVY-TOLEDANO, S., additional, BREDOUX, R., additional, MICHEL, H., additional, NURDEN, A., additional, CAEN, J. P., additional, and DEGOS, L., additional
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- 1976
- Full Text
- View/download PDF
113. ADULT HUMAN SAPHENOUS VEIN ENDOTHELIAL CELLS : ASSESMENT OF THEIR REPRODUCTIVE CAPACITY AND FUNCTIONAL INTEGRITY PRIOR TO IMPLANTATION ON A VASCULAR GRAFT
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Lesèche, G, Tobelem, G, Caen, J, and Andreassian, B
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- 1987
- Full Text
- View/download PDF
114. CULTURED HUMAN MICROVASCULAR ENDOTHELIAL CELLS SYNTHESIZE CYCLOOXYGENASE METABOLITES FROM ARACHIDONIC ACID IN RESPONSE TO LEUKOTRIENES C4 AND D4
- Author
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Carreras, L O, Maclouf, J, Tobelem, G, and Caen, J P
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- 1987
- Full Text
- View/download PDF
115. Effects Of A Monoclonal Antibody To Human Platelet Glycoprotein I On Platelet - Von Willebrand Factor Subendothelium Interactions
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Ruan, C, Tobelem, G, McMichael, A, Drouet, L, Legrand, Y, and Caen, J P
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- 1981
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116. Microfibrils (MF) Platelet Interaction: Requirement Of Von Willebrand Factor In Platelet Adhesion To A Placenta Microfibrillar Component (PMC)
- Author
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Fauvel, F, Legrand, Y J, Gutman, N, Muh, J P, Tobelem, G, Souchon, H, Karniguian, A, and Caen, J P
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- 1981
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117. TYPE IIB VON WILLEBRAND DISEASE WITH CHRONIC THROMBOCYTOPENIA : BENEFICIAL EFFECT OF CRYOPRECIPITATE SUPERNATANT INFUSION ON PLATELET COUNT AND BLEEDING
- Author
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Derlon, A, Le Querrec, A, Lebrun, E, Tobelem, G, and Thomas, M
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- 1987
- Full Text
- View/download PDF
118. PLATELET DERIVED GROWTH FACTOR (PDGF) BINDS TO HUMAN BONE MARROW FIBROBLASTS AND STIMULATES THEIR PROLIFERATION.
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Bryckaert, M C, Wasteson, A, Lindroth, M, and Tobelem, G C
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- 1987
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119. PLATELET DERIVED GROWTH FACTOR (PDGF) BINDS TO HUMAN PLATELETS AND MODULATES PLATELET ACTIVATION
- Author
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Bryckaert, M C, Wasteson, A, Tobelem, G, Rendu, F, and Caen, J P
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- 1987
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120. HEPARIN STIMULATES FIBROBLAST GROWTH INDUCED BY PDGF
- Author
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Dupuy, E, Rohrlich, P S, and Tobelem, G
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- 1987
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121. HEPARIN BINDING TO ENDOTHELIAL CELLS POTENTIATES THROMBINSTIMULATED PGI2 PRoDUCTION
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Bårzu, T, Molho, P, Cariou, R, Tobelem, G, and Caen, J
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- 1987
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122. Thrombin mitogenic responses and protein phosphorylation are different in cultured human endothelial cells derived from large and microvessels
- Author
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Tobelem, G [INSERM U 150, Paris (France)]
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- 1989
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123. Strategies to Enhance the Efficiency of Endothelial Progenitor Cell Therapy by Ephrin B2 Pretreatment and Coadministration with Smooth Muscle Progenitor Cells on Vascular Function During the Wound-Healing Process in Irradiated or Nonirradiated Condition.
- Author
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Foubert P, Squiban C, Holler V, Buard V, Dean C, Levy BI, Benderitter M, Silvestre JS, Tobelem G, and Tamarat R
- Subjects
- Aged, Animals, Ephrin-B2, Female, Humans, Immunohistochemistry, Male, Mice, Middle Aged, Endothelial Progenitor Cells metabolism, Myocytes, Smooth Muscle metabolism, Wound Healing drug effects
- Abstract
Endothelial progenitor cell (EPC) transplantation has beneficial effects for therapeutic neovascularization. We therefore assessed the effect of a therapeutic strategy based on EPC administration in the healing of radiation-induced damage. To improve cell therapy for clinical use, we used pretreatment with ephrin B2-Fc (Eph-B2-Fc) and/or coadministration with smooth muscle progenitor cells. At day 3, EPCs promoted dermal wound healing in both nonirradiated and irradiated mice by 1.2- and 1.15-fold, respectively, compared with animals injected with phosphate-buffered saline. In addition, EPCs also improved skin-blood perfusion and capillary density in both irradiated and nonirradiated mice compared with PBS-injected animals. We also demonstrated that activation with Eph-B2-Fc increased wound closure by 1.6-fold compared with unstimulated EPCs in nonirradiated mice. Interestingly, the beneficial effect of Eph-B2-Fc was abolished in irradiated animals. In addition, we found that Eph-B2-Fc stimulation did not improve EPC-induced vascular permeability or adhesiveness compared to unstimulated EPCs. We hypothesized that this effect was due to high oxidative stress during irradiation, leading to inhibition of EPCs' beneficial effect on vascular function. In this line, we demonstrated that, in irradiated conditions, N-acetyl-l-cysteine treatment restored the beneficial effect of EPC stimulation with Eph-B2-Fc in the wound healing process. In conclusion, stimulation by Eph-B2-Fc improved the beneficial effect of EPCs in physiological conditions and irradiated conditions only in association with antioxidant treatment. Additionally, cotherapy was beneficial in pathological conditions.
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- 2015
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124. Neuropilin-1 is upregulated in hepatocellular carcinoma and contributes to tumour growth and vascular remodelling.
- Author
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Bergé M, Allanic D, Bonnin P, de Montrion C, Richard J, Suc M, Boivin JF, Contrerès JO, Lockhart BP, Pocard M, Lévy BI, Tucker GC, Tobelem G, and Merkulova-Rainon T
- Subjects
- Animals, Carcinoma, Hepatocellular drug therapy, Carcinoma, Hepatocellular pathology, Cell Division drug effects, Cell Division physiology, Disease Progression, Female, Gene Expression Regulation, Neoplastic physiology, Hep G2 Cells, Hepatocyte Growth Factor metabolism, Hepatocyte Growth Factor pharmacology, Humans, Liver Neoplasms drug therapy, Liver Neoplasms pathology, Male, Mice, Mice, Inbred C57BL, Mice, Transgenic, Neovascularization, Pathologic drug therapy, Neovascularization, Pathologic pathology, Neuropilin-1 antagonists & inhibitors, Neuropilin-1 genetics, Peptides pharmacology, Up-Regulation physiology, Carcinoma, Hepatocellular physiopathology, Liver Neoplasms physiopathology, Neovascularization, Pathologic physiopathology, Neuropilin-1 metabolism
- Abstract
Background & Aims: Neuropilin-1 (NRP1) is a transmembrane co-receptor for semaphorins and heparin-binding pro-angiogenic cytokines, principally members of the vascular endothelial growth factor family. Recent studies revealed an important role of NRP1 in angiogenesis and malignant progression of many cancers. The role of NRP1 in the development of hepatocellular carcinoma (HCC) is not completely understood., Methods: We used human tissue microarrays and a mouse transgenic model of HCC to establish the spatio-temporal patterns of NRP1 expression in HCC. To evaluate the therapeutic potential of targeting NRP1 in HCC, we treated HCC mice with peptide N, an NRP1 binding recombinant protein and competitive inhibitor of the VEGF-A(165)/NRP1 interaction., Results: We demonstrate that NRP1 is expressed in hepatic endothelial cells of both human healthy biopsies and in HCC samples, but not in normal hepatocytes. We found that increased NRP1 expression in human tumour hepatocytes is significantly associated with primary HCC. Using RT-PCR, Western blot and immunofluorescence analysis we show that NRP1 expression in the liver of transgenic HCC mice is increased with disease progression, in both vascular and tumour compartments. Blocking NRP1 function with peptide N leads to the inhibition of vascular remodelling and tumour liver growth in HCC mice., Conclusions: Our results indicate a specific role of NRP1 in HCC growth and vascular remodelling and highlight the possibility of therapeutically targeting NRP1 for the treatment of HCC., (Copyright © 2011 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.)
- Published
- 2011
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125. Small interfering RNAs induce target-independent inhibition of tumor growth and vasculature remodeling in a mouse model of hepatocellular carcinoma.
- Author
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Bergé M, Bonnin P, Sulpice E, Vilar J, Allanic D, Silvestre JS, Lévy BI, Tucker GC, Tobelem G, and Merkulova-Rainon T
- Subjects
- Animals, Carcinoma, Hepatocellular blood supply, Carcinoma, Hepatocellular genetics, Cells, Cultured, Down-Regulation drug effects, Female, Humans, Liver Neoplasms blood supply, Liver Neoplasms genetics, Male, Mice, Mice, Inbred C57BL, Mice, Transgenic, Molecular Targeted Therapy, Neovascularization, Pathologic genetics, RNA Interference physiology, Tumor Burden drug effects, Carcinoma, Hepatocellular pathology, Cell Proliferation drug effects, Liver Neoplasms pathology, Neovascularization, Pathologic prevention & control, RNA, Small Interfering pharmacology
- Abstract
RNA interference mediated by small interfering RNAs (siRNAs) has emerged as a potential therapeutic approach to treat various diseases, including cancer. Recent studies with several animal models of posttraumatic revascularization demonstrated that synthetic siRNAs may produce therapeutic effects in a target-independent manner through the stimulation of the toll-like receptor-3 (TLR3)/interferon pathway and suppression of angiogenesis. To analyze the impact of siRNAs on tumor angiogenesis, we injected transgenic mice developing hepatocellular carcinoma (HCC) with either control siRNAs or siRNA targeting neuropilin-1. We found that treatment with these siRNAs led to a comparable reduction in tumor liver volume and to inhibition of tumor vasculature remodeling. We further determined that TLR3, which recognizes double-stranded siRNA, was up-regulated in mouse HCC. Treatment of HCC mice with polyinosinic-polycytidylic acid [poly(I:C)], a TLR3 agonist, led to both a reduction of tumor liver enlargement and a decrease in hepatic arterial blood flow, indicating that TLR3 is functional and may mediate both anti-angiogenic and anti-tumor responses. We also demonstrated that siRNAs increased interferon-γ levels in the liver. In vitro, interferon-γ inhibited proliferation of endothelial cells. In addition, we found that siRNAs inhibited endothelial cell proliferation and morphogenesis in an interferon-γ-independent manner. Our results suggest that synthetic siRNAs inhibit target-independently HCC growth and angiogenesis through the activation of the innate interferon response and by directly inhibiting endothelial cell function.
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- 2010
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126. Further pharmacological and genetic evidence for the efficacy of PlGF inhibition in cancer and eye disease.
- Author
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Van de Veire S, Stalmans I, Heindryckx F, Oura H, Tijeras-Raballand A, Schmidt T, Loges S, Albrecht I, Jonckx B, Vinckier S, Van Steenkiste C, Tugues S, Rolny C, De Mol M, Dettori D, Hainaud P, Coenegrachts L, Contreres JO, Van Bergen T, Cuervo H, Xiao WH, Le Henaff C, Buysschaert I, Kharabi Masouleh B, Geerts A, Schomber T, Bonnin P, Lambert V, Haustraete J, Zacchigna S, Rakic JM, Jiménez W, Noël A, Giacca M, Colle I, Foidart JM, Tobelem G, Morales-Ruiz M, Vilar J, Maxwell P, Vinores SA, Carmeliet G, Dewerchin M, Claesson-Welsh L, Dupuy E, Van Vlierberghe H, Christofori G, Mazzone M, Detmar M, Collen D, and Carmeliet P
- Subjects
- Angiogenesis Inhibitors therapeutic use, Animals, Antibodies, Monoclonal therapeutic use, Carcinoma, Hepatocellular blood supply, Carcinoma, Hepatocellular prevention & control, Choroid blood supply, Disease Models, Animal, Eye Diseases pathology, Humans, Liver Neoplasms, Experimental blood supply, Liver Neoplasms, Experimental prevention & control, Mice, Mice, Inbred BALB C, Mice, Inbred C57BL, Mice, Transgenic, Papilloma blood supply, Papilloma chemically induced, Papilloma prevention & control, Placenta Growth Factor, Skin Neoplasms blood supply, Skin Neoplasms chemically induced, Skin Neoplasms prevention & control, Neovascularization, Physiologic drug effects, Pregnancy Proteins antagonists & inhibitors, Pregnancy Proteins metabolism
- Abstract
Our findings that PlGF is a cancer target and anti-PlGF is useful for anticancer treatment have been challenged by Bais et al. Here we take advantage of carcinogen-induced and transgenic tumor models as well as ocular neovascularization to report further evidence in support of our original findings of PlGF as a promising target for anticancer therapies. We present evidence for the efficacy of additional anti-PlGF antibodies and their ability to phenocopy genetic deficiency or silencing of PlGF in cancer and ocular disease but also show that not all anti-PlGF antibodies are effective. We also provide additional evidence for the specificity of our anti-PlGF antibody and experiments to suggest that anti-PlGF treatment will not be effective for all tumors and why. Further, we show that PlGF blockage inhibits vessel abnormalization rather than density in certain tumors while enhancing VEGF-targeted inhibition in ocular disease. Our findings warrant further testing of anti-PlGF therapies., (Copyright 2010 Elsevier Inc. All rights reserved.)
- Published
- 2010
- Full Text
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127. Cross-talk between the VEGF-A and HGF signalling pathways in endothelial cells.
- Author
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Sulpice E, Ding S, Muscatelli-Groux B, Bergé M, Han ZC, Plouet J, Tobelem G, and Merkulova-Rainon T
- Subjects
- Cells, Cultured, Hepatocyte Growth Factor genetics, Humans, Mitogen-Activated Protein Kinases genetics, Mitogen-Activated Protein Kinases metabolism, Proto-Oncogene Proteins c-met genetics, Proto-Oncogene Proteins c-met metabolism, Vascular Endothelial Growth Factor A genetics, Vascular Endothelial Growth Factor Receptor-2 genetics, Vascular Endothelial Growth Factor Receptor-2 metabolism, Endothelial Cells metabolism, Hepatocyte Growth Factor metabolism, Receptor Cross-Talk, Signal Transduction, Vascular Endothelial Growth Factor A metabolism
- Abstract
Background Information: Endothelial cells play a major role in angiogenesis, the process by which new blood vessels arise from a pre-existing vascular bed. VEGF-A (vascular endothelial growth factor-A) is a key regulator of angiogenesis during both development and in adults. HGF (hepatocyte growth factor) is a pleiotropic cytokine that may promote VEGF-A-driven angiogenesis, although the signalling mechanisms underlying this co-operation are not completely understood., Results: We analysed the effects of the combination of VEGF-A and HGF on the activation of VEGFR-2 (VEGF receptor-2) and c-met receptors, and on the stimulation of downstream signalling pathways in endothelial cells. We found that VEGFR-2 and c-met do not physically associate and do not transphosphorylate each other, suggesting that co-operation involves signalling events more distal from receptor activation. We demonstrate that the VEGF isoform VEGF-A(165) and HGF stimulate a similar set of MAPKs (mitogen-activated protein kinases), although the kinetics and strengths of the activation differ depending on the growth factor and pathway. An enhanced activation of the signalling was observed when endothelial cells were stimulated by the combination of VEGF-A(165) and HGF. Moreover, the combination of VEGF-A and HGF results in a statistically significant synergistic activation of ERK1/2 (extracellular-signal-regulated kinase 1/2) and p38 kinases. We demonstrated that VEGF-A(165) and HGF activate FAK (focal adhesion kinase) with different kinetics and stimulate the recruitment of phosphorylated FAK to different subsets of focal adhesions. VEGF-A(165) and HGF regulate distinct morphogenic aspects of the cytoskeletal remodelling that are associated with the preferential activation of Rho or Rac respectively, and induce structurally distinct vascular-like patterns in vitro in a Rho- or Rac-dependent manner., Conclusions: Under angiogenic conditions, combining VEGF-A with HGF can promote neovascularization by enhancing intracellular signalling and allowing more finely regulated control of the signalling molecules involved in the regulation of the cytoskeleton and cellular migration and morphogenesis.
- Published
- 2009
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128. Angiotensinogen delays angiogenesis and tumor growth of hepatocarcinoma in transgenic mice.
- Author
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Vincent F, Bonnin P, Clemessy M, Contrerès JO, Lamandé N, Gasc JM, Vilar J, Hainaud P, Tobelem G, Corvol P, and Dupuy E
- Subjects
- Adaptor Proteins, Signal Transducing, Angiotensinogen biosynthesis, Angiotensinogen blood, Angiotensinogen genetics, Animals, Calcium-Binding Proteins, Cell Growth Processes physiology, Ephrin-B2 biosynthesis, Female, Humans, Intracellular Signaling Peptides and Proteins, Liver metabolism, Liver pathology, Liver Neoplasms, Experimental genetics, Liver Neoplasms, Experimental metabolism, Liver Neoplasms, Experimental pathology, Male, Membrane Proteins biosynthesis, Mice, Mice, Inbred C57BL, Mice, Transgenic, Neovascularization, Pathologic genetics, Neovascularization, Pathologic metabolism, Neovascularization, Pathologic pathology, Proto-Oncogene Proteins biosynthesis, RNA, Messenger biosynthesis, RNA, Messenger genetics, Receptor, Notch4, Receptors, Notch biosynthesis, Angiotensinogen metabolism, Liver Neoplasms, Experimental blood supply
- Abstract
Angiotensinogen, a member of the serpin family, is involved in the suppression of tumor growth and metastasis. To investigate whether human angiotensinogen protects against tumor progression in vivo, we established an original bitransgenic model in which transgenic mice expressing human angiotensinogen (Hu-AGT-TG mice) were crossed with a transgenic mouse model of hepatocellular carcinoma (HCC-TG mice). Bitransgenic mice overexpressing human angiotensinogen (HCC/Hu-AGT-TG) had a significantly longer survival time than the HCC-TG mice and a reduction of both tumor growth and blood flow velocities in the liver. This antitumor effect of angiotensinogen is related to a reduced angiogenesis, impaired expression of endothelial arterial markers (active Notch4, Delta-like 4 ligand, and ephrin B2) with a decrease of arterial vessel density in HCC/Hu-AGT-TG mice liver. Overexpression of human angiotensinogen decreases angiogenesis, and prevents tumor sinusoids from remodeling and arterialization, thus delaying tumor progression in vivo.
- Published
- 2009
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129. Coadministration of endothelial and smooth muscle progenitor cells enhances the efficiency of proangiogenic cell-based therapy.
- Author
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Foubert P, Matrone G, Souttou B, Leré-Déan C, Barateau V, Plouët J, Le Ricousse-Roussanne S, Lévy BI, Silvestre JS, and Tobelem G
- Subjects
- Angiotensin I metabolism, Animals, Endothelial Cells metabolism, Humans, Ischemia metabolism, Male, Mice, Mice, Nude, Myocytes, Smooth Muscle cytology, Receptor, TIE-2 metabolism, Signal Transduction, Endothelial Cells transplantation, Hindlimb blood supply, Ischemia therapy, Myocytes, Smooth Muscle transplantation, Neovascularization, Physiologic, Stem Cell Transplantation, Stem Cells cytology, Stem Cells metabolism
- Abstract
Cell-based therapy is a promising approach designed to enhance neovascularization and function of ischemic tissues. Interaction between endothelial and smooth muscle cells regulates vessels development and remodeling and is required for the formation of a mature and functional vascular network. Therefore, we assessed whether coadministration of endothelial progenitor cells (EPCs) and smooth muscle progenitor cells (SMPCs) can increase the efficiency of cell therapy. Unilateral hindlimb ischemia was surgically induced in athymic nude mice treated with or without intravenous injection of EPCs (0.5 x 10(6)), SMPCs (0.5 x 10(6)) and EPCs+SMPCs (0.25 x 10(6)+0.25 x 10(6)). Vessel density and foot perfusion were increased in mice treated with EPCs+SMPCs compared to animals receiving EPCs alone or SMPCs alone (P<0.001). In addition, capillary and arteriolar densities were enhanced in EPC+SMPC-treated mice compared to SMPC and EPC groups (P<0.01). We next examined the role of Ang-1/Tie2 signaling in the beneficial effect of EPC and SMPC coadministration. Small interfering RNA directed against Ang-1-producing SMPCs or Tie2-expressing EPCs blocked vascular network formation in Matrigel coculture assays, reduced the rate of incorporated EPCs within vascular structure, and abrogated the efficiency of cell therapy. Production of Ang-1 by SMPCs activates Tie2-expressing EPCs, resulting in increase of EPC survival and formation of a stable vascular network. Subsequently, the efficiency of EPC- and SMPC-based cotherapy is markedly increased. Therefore, coadministration of different types of vascular progenitor cells may constitute a novel therapeutic strategy for improving the treatment of ischemic diseases.
- Published
- 2008
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130. Netrin-4 inhibits angiogenesis via binding to neogenin and recruitment of Unc5B.
- Author
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Lejmi E, Leconte L, Pédron-Mazoyer S, Ropert S, Raoul W, Lavalette S, Bouras I, Feron JG, Maitre-Boube M, Assayag F, Feumi C, Alemany M, Jie TX, Merkulova T, Poupon MF, Ruchoux MM, Tobelem G, Sennlaub F, and Plouët J
- Subjects
- Animals, Cattle, Cell Line, Tumor, Cells, Cultured, Chemotaxis, Female, Humans, Lasers adverse effects, Male, Mice, Mice, Inbred BALB C, Mice, Nude, Neoplasms, Experimental blood supply, Nerve Growth Factors genetics, Nerve Growth Factors metabolism, Netrin Receptors, Netrins, Prostatic Neoplasms pathology, Protein Binding physiology, Recombinant Proteins pharmacology, Transplantation, Heterologous, Up-Regulation genetics, Endothelial Cells cytology, Membrane Proteins metabolism, Neovascularization, Pathologic, Nerve Growth Factors physiology, Receptors, Cell Surface metabolism
- Abstract
Netrins are secreted molecules with roles in axon guidance and angiogenesis. We identified Netrin-4 as a gene specifically overexpressed in VEGF-stimulated endothelial cells (EC) in vitro as well as in vivo. Knockdown of Netrin-4 expression in EC increased their ability to form tubular structures on Matrigel. To identify which receptor is involved, we showed by quantitative RT-PCR that EC express three of the six Netrin-1 cognate receptors: neogenin, Unc5B, and Unc5C. In contrast to Netrin-1, Netrin-4 bound only to neogenin but not to Unc5B or Unc5C receptors. Neutralization of Netrin-4 binding to neogenin by blocking antibodies abolished the chemotactic effect of Netrin-4. Furthermore, the silencing of either neogenin or Unc5B abolished Netrin-4 inhibitory effect on EC migration, suggesting that both receptors are essential for its function in vitro. Coimmunoprecipitation experiments demonstrated that Netrin-4 increased the association between Unc5B and neogenin on VEGF- or FGF-2-stimulated EC. Finally, we showed that Netrin-4 significantly reduced pathological angiogenesis in Matrigel and laser-induced choroidal neovascularization models. Interestingly, Netrin-4, neogenin, and Unc5B receptor expression was up-regulated in choroidal neovessel EC after laser injury. Moreover, Netrin-4 overexpression delayed tumor angiogenesis in a model of s.c. xenograft. We propose that Netrin-4 acts as an antiangiogenic factor through binding to neogenin and recruitment of Unc5B.
- Published
- 2008
- Full Text
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131. Neuropilin-1 and neuropilin-2 act as coreceptors, potentiating proangiogenic activity.
- Author
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Sulpice E, Plouët J, Bergé M, Allanic D, Tobelem G, and Merkulova-Rainon T
- Subjects
- Cell Culture Techniques, DNA Replication, Endothelium, Vascular cytology, Hepatocyte Growth Factor genetics, Hepatocyte Growth Factor physiology, Humans, Neuropilin-1 genetics, Neuropilin-2 genetics, Protein Binding, RNA, Small Interfering genetics, Recombinant Proteins metabolism, Transfection, Umbilical Veins, Vascular Endothelial Growth Factor A genetics, Vascular Endothelial Growth Factor A physiology, Endothelium, Vascular physiology, Neovascularization, Physiologic, Neuropilin-1 metabolism, Neuropilin-2 metabolism
- Abstract
Neuropilin-1 and -2 (NRP1 and NRP2) are the transmembrane glycoproteins interacting with 2 types of ligands: class III semaphorins and several members of the VEGF family, the main regulators of blood and lymphatic vessel growth. We show here that both NRP1 and NRP2 can also bind hepatocyte growth factor (HGF). HGF is a pleiotropic cytokine and potent proangiogenic molecule that acts on its target cells by binding to the c-met receptor. We found that the N-terminal domain of HGF is involved in the interaction with neuropilins. We demonstrated that invalidation of NRP1 or NRP2 by RNA interference in human umbilical vein endothelial cells (HUVECs) decreased HGF-induced c-met phosphorylation and VEGF-A(165)- and HGF-mediated intracellular signaling. Accordingly, the disruption of NRP1 or NRP2 binding to VEGF-A(165) or HGF with a blocking antibody, decreased the proliferation and migration of endothelial cells. This effect may be further enhanced if VEGF-A(165) or HGF binding to both NRP1 and NRP2 was disrupted. Using a mouse Matrigel model, we demonstrated that NRP1 is essential for HGF-mediated angiogenesis in vivo. Our results suggest that, in endothelial cells, both NRP1 and NRP2 function as proangiogenic coreceptors, potentiating the activity of at least 2 major proangiogenic cytokines, VEGF-A(165) and HGF.
- Published
- 2008
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132. Role of human smooth muscle cell progenitors in atherosclerotic plaque development and composition.
- Author
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Zoll J, Fontaine V, Gourdy P, Barateau V, Vilar J, Leroyer A, Lopes-Kam I, Mallat Z, Arnal JF, Henry P, Tobelem G, and Tedgui A
- Subjects
- Aged, Animals, Apolipoproteins E physiology, Atherosclerosis metabolism, Atherosclerosis pathology, Cell Separation, Cells, Cultured, DNA-Binding Proteins physiology, Disease Progression, Endothelial Cells cytology, Female, Fetal Blood cytology, Humans, Male, Mice, Middle Aged, Atherosclerosis etiology, Hematopoietic Stem Cells physiology, Muscle, Smooth, Vascular cytology
- Abstract
Aims: We analysed the possible protective role of human endothelial (EPCs) and smooth muscle (SPCs) progenitor cells on atherosclerosis development in apoE(-/-)RAG2(-/-) mice. We determined plasma levels of SPCs in coronary patients., Methods and Results: ApoE(-/-)RAG2(-/-) mice received four intravenous injections of saline, 5 x 10(5) SPCs, or 5 x 10(5) EPCs every other week, one (preventive approach) or 12(curative approach) weeks after starting a high fat diet. Derived-SPC levels were quantified from blood mononuclear cells of patients with stable angina (n = 10) and acute coronary syndromes (ACS, n = 9). SPCs reduced atherosclerosis development by 42% (P < 0.001), but had no effect on lesion progression. In the SPC group, collagen and smooth muscle cell content were increased (+80%, P < 0.001, +46%, P < 0.05, respectively), and macrophage content was decreased (-41%, P < 0.05). In the curative approach, macrophage content decreased by 40.5% (P < 0.05) after SPC injection. EPC injection had no effect on atherosclerosis development or progression. Peripheral blood-derived SPC levels were reduced in patients with ACS compared with stable angina patients (P < 0.05)., Conclusion: We demonstrate that SPCs limit plaque development and promote changes in plaque composition towards a stable phenotype in mice. Our finding in patients suggests that reduced peripheral blood-derived SPC levels might represent a mechanism contributing to plaque destabilization.
- Published
- 2008
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133. [Physiologic and neoplastic angiogenesis].
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Tobelem G
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- Humans, Vascular Endothelial Growth Factor A physiology, Neoplasms blood supply, Neovascularization, Pathologic, Neovascularization, Physiologic
- Published
- 2008
134. [Angiogenesis and hematologic malignancy].
- Author
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Zini JM and Tobelem G
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- Angiogenesis Inhibitors physiology, Angiogenic Proteins physiology, Fibroblast Growth Factor 2 physiology, Humans, Leukemia drug therapy, Lymphoma drug therapy, Myelodysplastic Syndromes drug therapy, Neovascularization, Pathologic etiology, Vascular Endothelial Growth Factor A physiology, Angiogenesis Inhibitors therapeutic use, Hematologic Neoplasms drug therapy, Neovascularization, Pathologic drug therapy
- Abstract
Angiogenesis plays an important role in the progression of tumors. This relationship has been described in several hematologic malignancies. Vascular endothelial growth factor and basic fibroblast growth factor are predictors of poor prognosis in leukemia and non Hodgkin's lymphoma. Bone marrow microvessels were found increased in multiple myeloma, but also in lymphoma and in acute lymphoblastic leukemia. Microvessel density is correlated with decreased survival in myeloma patients and relapse or resistance to chemotherapy in lymphoma. New drugs with antiangiogenic activity such as bevacizumab (binding and inactivation of VEGF) or VEGF-tyrosine kinase inhibitors have shown promising results in phase 1 trials. It will therefore be a future challenge to integrate anti-angiogenesis agents in currently existing treatment protocols to improve the outcome of therapy.
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- 2007
135. PSGL-1-mediated activation of EphB4 increases the proangiogenic potential of endothelial progenitor cells.
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Foubert P, Silvestre JS, Souttou B, Barateau V, Martin C, Ebrahimian TG, Leré-Déan C, Contreres JO, Sulpice E, Levy BI, Plouët J, Tobelem G, and Le Ricousse-Roussanne S
- Subjects
- Animals, Base Sequence, Cell Adhesion, Cells, Cultured, DNA Primers genetics, E-Selectin metabolism, Endothelial Cells cytology, Endothelial Cells drug effects, Ephrin-B2 metabolism, Ephrin-B2 pharmacology, Fetal Blood cytology, Fetal Stem Cells cytology, Fetal Stem Cells drug effects, Hindlimb blood supply, Humans, In Vitro Techniques, Ischemia metabolism, Ischemia pathology, Ischemia therapy, Male, Membrane Glycoproteins antagonists & inhibitors, Membrane Glycoproteins genetics, Mice, Mice, Nude, P-Selectin metabolism, RNA Interference, RNA, Small Interfering genetics, Receptor, EphB4 antagonists & inhibitors, Receptor, EphB4 genetics, Endothelial Cells metabolism, Fetal Stem Cells metabolism, Membrane Glycoproteins metabolism, Neovascularization, Physiologic drug effects, Receptor, EphB4 metabolism
- Abstract
Endothelial progenitor cell (EPC) transplantation has beneficial effects for therapeutic neovascularization; however, only a small proportion of injected cells home to the lesion and incorporate into the neocapillaries. Consequently, this type of cell therapy requires substantial improvement to be of clinical value. Erythropoietin-producing human hepatocellular carcinoma (Eph) receptors and their ephrin ligands are key regulators of vascular development. We postulated that activation of the EphB4/ephrin-B2 system may enhance EPC proangiogenic potential. In this report, we demonstrate in a nude mouse model of hind limb ischemia that EphB4 activation with an ephrin-B2-Fc chimeric protein increases the angiogenic potential of human EPCs. This effect was abolished by EphB4 siRNA, confirming that it is mediated by EphB4. EphB4 activation enhanced P selectin glycoprotein ligand-1 (PSGL-1) expression and EPC adhesion. Inhibition of PSGL-1 by siRNA reversed the proangiogenic and adhesive effects of EphB4 activation. Moreover, neutralizing antibodies to E selectin and P selectin blocked ephrin-B2-Fc-stimulated EPC adhesion properties. Thus, activation of EphB4 enhances EPC proangiogenic capacity through induction of PSGL-1 expression and adhesion to E selectin and P selectin. Therefore, activation of EphB4 is an innovative and potentially valuable therapeutic strategy for improving the recruitment of EPCs to sites of neovascularization and thereby the efficiency of cell-based proangiogenic therapy.
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- 2007
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136. Ex vivo generation of mature and functional human smooth muscle cells differentiated from skeletal myoblasts.
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Le Ricousse-Roussanne S, Larghero J, Zini JM, Barateau V, Foubert P, Uzan G, Liu X, Lacassagne MN, Ternaux B, Robert I, Benbunan M, Vilquin JT, Vauchez K, Tobelem G, and Marolleau JP
- Subjects
- Animals, Biomarkers analysis, Cells, Cultured, Drug Combinations, Epithelial Cells physiology, Female, Humans, Mice, Mice, Inbred NOD, Mice, SCID, Muscle Fibers, Skeletal physiology, Myoblasts, Skeletal drug effects, Myoblasts, Skeletal metabolism, Myoblasts, Skeletal transplantation, Myocytes, Smooth Muscle metabolism, Myocytes, Smooth Muscle transplantation, Neovascularization, Physiologic, Transplantation, Heterologous, Vascular Endothelial Growth Factor A pharmacology, Cell Differentiation, Collagen pharmacology, Laminin pharmacology, Myoblasts, Skeletal physiology, Myocytes, Smooth Muscle physiology, Proteoglycans pharmacology, Tissue Culture Techniques
- Abstract
We described the ex vivo production of mature and functional human smooth muscle cells (SMCs) derived from skeletal myoblasts. Initially, myoblasts expressed all myogenic cell-related markers such as Myf5, MyoD and Myogenin and differentiate into myotubes. After culture in a medium containing vascular endothelial growth factor (VEGF), these cells were shown to have adopted a differentiated SMC identity as demonstrated by alphaSMA, SM22alpha, calponin and smooth muscle-myosin heavy chain expression. Moreover, the cells cultured in the presence of VEGF did not express MyoD anymore and were unable to fuse in multinucleated myotubes. We demonstrated that myoblasts-derived SMCs (MDSMCs) interacted with endothelial cells to form, in vitro, a capillary-like network in three-dimensional collagen culture and, in vivo, a functional vascular structure in a Matrigel implant in nonobese diabetic-severe combined immunodeficient mice. Based on the easily available tissue source and their differentiation into functional SMCs, these data argue that skeletal myoblasts might represent an important tool for SMCs-based cell therapy.
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- 2007
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137. Ultrasonic assessment of hepatic blood flow as a marker of mouse hepatocarcinoma.
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Bonnin P, Villemain A, Vincent F, Debbabi H, Silvestre JS, Contreres JO, Levy BI, Tobelem G, and Dupuy E
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- Animals, Blood Volume, Female, Liver blood supply, Male, Mice, Mice, Transgenic, Models, Animal, Radiography, Ultrasonography, Doppler, Color, Ultrasonography, Doppler, Pulsed, Carcinoma, Hepatocellular diagnostic imaging, Liver diagnostic imaging, Liver Neoplasms diagnostic imaging, Neovascularization, Pathologic diagnostic imaging, Signal Processing, Computer-Assisted
- Abstract
Two-dimensional color-coded pulsed Doppler ultrasonography (US) with a 12-MHz linear transducer was used to follow tumor growth and neoangiogenesis development in 12 transgenic mice developing a whole liver hepatocellular carcinoma (HCC) induced by the expression of SV40-T antigen. In this model, male mice developed HCC at various temporal and histologic stages (hyperplastic, four-eight wk; nodular, 12 wk; diffuse carcinoma, 16-20 wk), whereas female mice remained tumor free. Seven age-matched tumor-free mice were used as controls. Liver volume was calculated from B-mode images of the abdomen. Blood flow waveforms were recorded from the hepatic tumor-feeding artery upstream from the tumor vessels, allowing quantitative blood flow velocity measurements. Measurements were performed every four weeks from four to 20 weeks. As early as the hyperplastic stage (eight weeks), liver volume was increased by 2.7-fold, hepatic artery peak-systolic blood flow velocities (BFV) by 1.5-fold, end-diastolic BFV by 1.6-fold and mean BFV by 2.0-fold compared with control values (p < 0.001). Differences increased until 20 weeks and peak-systolic reached 90 +/- 6, end-diastolic 54 +/- 5 and mean BFV 48 +/- 5 cm s(-1). Successive measurements of BFV were reproducible and intraobserver repeatability coefficient values were <3 cm s(-1). In contrast, mesenteric artery BFV, which did not supply tumor region, did not show any significant difference with respect to control values. Thus, an increase in BFV constitutes a functional evaluation of tumor vascularity. In preclinical studies in small animals, measurements of liver volume and blood flow velocities in hepatic tumor-feeding artery provide a useful, reproducible, noninvasive, easy-to-repeat tool to monitor tumor growth and neoangiogenesis in hepatocellular carcinoma in mice.
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- 2007
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138. The role of the vascular endothelial growth factor-Delta-like 4 ligand/Notch4-ephrin B2 cascade in tumor vessel remodeling and endothelial cell functions.
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Hainaud P, Contrerès JO, Villemain A, Liu LX, Plouët J, Tobelem G, and Dupuy E
- Subjects
- Adaptor Proteins, Signal Transducing, Animals, Calcium-Binding Proteins, Carcinoma pathology, Carcinoma, Hepatocellular pathology, Endothelium, Vascular pathology, Endothelium, Vascular physiopathology, Female, Humans, Intracellular Signaling Peptides and Proteins genetics, Liver Neoplasms pathology, Membrane Proteins genetics, Mice, Mice, Inbred C57BL, Mice, Transgenic, Receptor, Notch4, Vascular Endothelial Growth Factor A physiology, Endothelium, Vascular physiology, Ephrin-B2 physiology, Intracellular Signaling Peptides and Proteins physiology, Membrane Proteins physiology, Proto-Oncogene Proteins physiology, Receptors, Notch physiology, Umbilical Veins physiology
- Abstract
Vascular endothelial growth factor (VEGF) and Delta-like 4 ligand (DLL4) are the only genes whose haploinsufficiency results in vascular abnormalities. Although many common pathways are up-regulated in both vascular development and tumor angiogenesis and in vascular remodeling, the role of the Delta/Notch pathway has not been clearly defined in tumor angiogenesis. In this study, we assessed the expression of DLL4, Notch4, and ephrin B2 in transgenic mice developing hepatocarcinoma characterized by a strong remodeling of the tumor sinusoids. We also investigated the role of VEGF in the expression and biological functions of these molecules on human venous endothelial cells. In transgenic livers, we showed that DLL4, active Notch4, and ephrin B2 were gradually up-regulated within the hepatocarcinoma progression and expressed on tumor sinusoidal endothelial cells. In venous endothelial cells, we showed that VEGF up-regulates DLL4 and presenilin, and increased the activation of Notch4, leading to an up-regulation of ephrin B2 with a down-regulation of Eph B4. We also showed that the activation of Notch4 is required for VEGF-induced up-regulation of ephrin B2 and the differentiation of human venous endothelial cells in vitro. Accordingly, the disruption of Notch4 signaling by pharmacologic inhibition of presenilin or addition of soluble DLL4 inhibited the effect of VEGF on human venous endothelial cell migration and differentiation. Our study strongly suggests that a coordinated activation of DDL4/Notch4 and ephrin B2 pathways downstream of VEGF plays a key role in the abnormal remodeling of tumor vessels.
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- 2006
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139. Tetrapeptide AcSDKP induces postischemic neovascularization through monocyte chemoattractant protein-1 signaling.
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Waeckel L, Bignon J, Liu JM, Markovits D, Ebrahimian TG, Vilar J, Mees B, Blanc-Brude O, Barateau V, Le Ricousse-Roussanne S, Duriez M, Tobelem G, Wdzieczak-Bakala J, Lévy BI, and Silvestre JS
- Subjects
- Animals, Bone Marrow Cells pathology, Cell Differentiation, Cell Line, Transformed, Chemokine CCL2 deficiency, Endothelium, Vascular drug effects, Endothelium, Vascular pathology, Femoral Artery pathology, Ischemia physiopathology, Mice, Mice, Inbred C57BL, Monocytes pathology, Signal Transduction drug effects, Chemokine CCL2 physiology, Hindlimb blood supply, Ischemia drug therapy, Neovascularization, Physiologic drug effects, Oligopeptides administration & dosage
- Abstract
Background: We investigated the putative proangiogenic activity and molecular pathway(s) of the tetrapeptide acetyl-N-Ser-Asp-Lys-Pro (AcSDKP) in a model of surgically induced hindlimb ischemia., Methods and Results: Hindlimb ischemia was induced by femoral artery ligature and an osmotic minipump was implanted subcutaneously to deliver low (0.12 mg/kg per day) or high (1.2 mg/kg per day) doses of AcSDKP, for 7 or 21 days. Angiography scores, arteriole density, capillary number, and foot perfusion were increased at day 21 in the high-dose AcSDKP-treated mice (by 1.9-, 1.8-, 1.3-, and 1.6-fold, respectively) compared with control animals (P<0.05, P<0.01, P<0.01, respectively). AcSDKP treatment for 24 hours upregulated the monocyte chemoattractant protein-1 (MCP-1) mRNA and protein levels by 1.5-fold in cultured endothelial cells (P<0.01). In the ischemic hindlimb model, administration of AcSDKP also enhanced MCP-1 mRNA levels by 90-fold in ischemic leg (P<0.001) and MCP-1 plasma levels by 3-fold (P<0.001 versus untreated ischemic control mice). MCP-1 levels upregulation were associated with a 2.3-fold increase in the number of Mac3-positive cells in ischemic area of AcSDKP-treated mice (P<0.001 versus untreated animals). Interestingly, AcSDKP-induced monocyte/macrophage infiltration and postischemic neovascularization was fully blunted in MCP-1-deficient animals., Conclusions: AcSDKP stimulates postischemic neovascularization through activation of a proinflammatory MCP-1-related pathway.
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- 2006
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140. Platelet factor 4 disrupts the intracellular signalling cascade induced by vascular endothelial growth factor by both KDR dependent and independent mechanisms.
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Sulpice E, Contreres JO, Lacour J, Bryckaert M, and Tobelem G
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- Antibodies immunology, Antibodies pharmacology, Cell Division, Cells, Cultured, DNA metabolism, Humans, MAP Kinase Signaling System drug effects, Mitogen-Activated Protein Kinase 1 antagonists & inhibitors, Mitogen-Activated Protein Kinase 1 metabolism, Mitogen-Activated Protein Kinase 3, Mitogen-Activated Protein Kinases antagonists & inhibitors, Mitogen-Activated Protein Kinases metabolism, Nucleic Acid Synthesis Inhibitors pharmacology, Phospholipase C gamma, Phosphorylation drug effects, Proto-Oncogene Proteins c-raf metabolism, Receptors, CXCR3, Receptors, Chemokine antagonists & inhibitors, Receptors, Chemokine metabolism, Type C Phospholipases metabolism, Umbilical Cord cytology, Umbilical Cord metabolism, Platelet Factor 4 pharmacology, Signal Transduction drug effects, Vascular Endothelial Growth Factor A pharmacology, Vascular Endothelial Growth Factor Receptor-2 metabolism
- Abstract
The mechanism by which the CXC chemokine platelet factor 4 (PF-4) inhibits endothelial cell proliferation is unclear. The heparin-binding domains of PF-4 have been reported to prevent vascular endothelial growth factor 165 (VEGF(165)) and fibroblast growth factor 2 (FGF2) from interacting with their receptors. However, other studies have suggested that PF-4 acts via heparin-binding independent interactions. Here, we compared the effects of PF-4 on the signalling events involved in the proliferation induced by VEGF(165), which binds heparin, and by VEGF(121), which does not. Activation of the VEGF receptor, KDR, and phospholipase Cgamma (PLCgamma) was unaffected in conditions in which PF-4 inhibited VEGF(121)-induced DNA synthesis. In contrast, VEGF(165)-induced phosphorylation of KDR and PLCgamma was partially inhibited by PF-4. These observations are consistent with PF-4 affecting the binding of VEGF(165), but not that of VEGF(121), to KDR. PF-4 also strongly inhibited the VEGF(165)- and VEGF(121)-induced mitogen-activated protein (MAP) kinase signalling pathways comprising Raf1, MEK1/2 and ERK1/2: for VEGF(165) it interacts directly or upstream from Raf1; for VEGF(121), it acts downstream from PLCgamma. Finally, the mechanism by which PF-4 may inhibit the endothelial cell proliferation induced by both VEGF(121) and VEGF(165), involving disruption of the MAP kinase signalling pathway downstream from KDR did not seem to involve CXCR3B activation.
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- 2004
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141. Ex vivo differentiated endothelial and smooth muscle cells from human cord blood progenitors home to the angiogenic tumor vasculature.
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Le Ricousse-Roussanne S, Barateau V, Contreres JO, Boval B, Kraus-Berthier L, and Tobelem G
- Subjects
- Animals, Blotting, Western methods, Cell Line, Tumor, Cell Movement, Flow Cytometry, Humans, Mice, Mice, SCID, Neoplasm Transplantation, Neovascularization, Pathologic, Reverse Transcriptase Polymerase Chain Reaction, Vascular Endothelial Growth Factor Receptor-1 analysis, Endothelial Cells cytology, Fetal Blood, Muscle, Smooth cytology, Stem Cells cytology
- Abstract
Objectives: Recent studies have provided increasing evidence that postnatal neovascularization does not rely exclusively on sprouting of preexisting vessels, but also involves bone marrow-derived circulating endothelial precursors (BM-EPCs). Animal studies revealed that neovascularization of ischemic tissue can be enhanced by BM-EPCs transplantation. But a possible limitation to the use of vascular precursors for therapeutic angiogenesis is the relatively low number of these cells. In this study, we demonstrate that ex vivo expanded differentiated endothelial cells (ECs) and smooth muscle cells (SMCs), may home to the tumor vasculature allowing targeting of transgene expression to the neoangiogenic site., Methods: Mononuclear cells (MNCs) or CD34+ -enriched cells were purified from cord blood. We have defined culture conditions in which we observed two types of clones easily differentiated according to their morphology: cobblestone or spindle-shaped. Phenotypic characterization was assessed by immunocytochemistry, flow cytometry analysis and polymerase reaction with reverse transcription. Formation of capillary-like network in vitro was studied in three-dimensional collagen culture. And recruitment of these cells to a tumoral neoangiogenic site was assessed into tumor-bearing Severe Combined Immunodeficient (SCID) mouse model., Results: The cobblestone cells uniformly positive for CD31, VE-cadherin, vWF, VEGF R1 and R2, ecNOS and incorporating acetylated LDL were ECs. Spindle-shaped cells expressed alpha-smooth muscle actin (alpha-SMA), Smooth Muscle Heavy Chain (SMHC), SM22 and calponin. They also displayed a carbachol-induced contractility in a medium containing IGF1. So we concluded that spindle-shaped cells were SMCs. ECs and SMCs interacted with each other to form a capillary like network in three-dimensional type I collagen culture. Moreover, these ex vivo differentiated cells are able to home to the tumor vasculature., Conclusion: We provide evidence that progenitors for ECs and SMCs circulate in human cord blood and differentiate into functional ECs and SMCs. These differentiated cells could provide a biomaterial for vascular cell therapy, because of their homing capacity to the neovascularization site.
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- 2004
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142. Impairment in ischemia-induced neovascularization in diabetes: bone marrow mononuclear cell dysfunction and therapeutic potential of placenta growth factor treatment.
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Tamarat R, Silvestre JS, Le Ricousse-Roussanne S, Barateau V, Lecomte-Raclet L, Clergue M, Duriez M, Tobelem G, and Lévy BI
- Subjects
- Angiography, Animals, Bone Marrow Cells cytology, Bone Marrow Cells drug effects, Bone Marrow Transplantation, Cell Differentiation drug effects, Cells, Cultured, Hindlimb blood supply, Hindlimb pathology, Hindlimb surgery, Ischemia drug therapy, Ischemia surgery, Laser-Doppler Flowmetry, Leukocytes, Mononuclear drug effects, Leukocytes, Mononuclear pathology, Mice, Placenta Growth Factor, Diabetes Mellitus, Experimental physiopathology, Ischemia pathology, Neovascularization, Physiologic drug effects, Pregnancy Proteins pharmacology
- Abstract
Mechanisms that hinder ischemia-induced neovascularization in diabetes remain poorly understood. We hypothesized that endogenous bone marrow mononuclear cell (BM-MNC) dysfunction may contribute to the abrogated postischemic revascularization reaction associated with diabetes. We first analyzed the effect of diabetes (streptozotocin, 40 mg/kg) on BM-MNC pro-angiogenic potential in a model of surgically induced hindlimb ischemia. In nondiabetic animals, transplantation of BM-MNCs isolated from nondiabetic animals raised the ischemic/nonischemic angiographic score, capillary number, and blood flow recovery by 1.8-, 2.7-, and 2.2-fold, respectively, over that of PBS-injected nondiabetic animals (P < 0.05). Administration of diabetic BM-MNCs also improved the neovascularization reaction in ischemic hindlimbs of nondiabetic mice but to a lesser extent from that observed with nondiabetic BM-MNC transplantation. In diabetic mice, injection of nondiabetic BM-MNCs was still more efficient than that of diabetic BM-MNCs. Such BM-MNC dysfunction was associated with the impairment of diabetic BM-MNC capacity to differentiate into endothelial progenitor cells (EPCs) in vitro and to participate in vascular-like structure formation in a subcutaneous Matrigel plug. Placenta growth factor (PlGF) administration improved by sixfold the number of EPCs differentiated from diabetic BM-MNCs in vitro and enhanced ischemic/nonischemic angiographic score, capillary number and blood flow recovery by 1.9-, 1.5- and 1.6-fold, respectively, over that of untreated diabetic animals (P < 0.01). Endogenous BM-MNC pro-angiogenic potential was affected in diabetes. Therapeutic strategy based on PlGF administration restored such defects and improved postischemic neovascularization in diabetic mice.
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- 2004
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143. Transplantation of bone marrow-derived mononuclear cells in ischemic apolipoprotein E-knockout mice accelerates atherosclerosis without altering plaque composition.
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Silvestre JS, Gojova A, Brun V, Potteaux S, Esposito B, Duriez M, Clergue M, Le Ricousse-Roussanne S, Barateau V, Merval R, Groux H, Tobelem G, Levy B, Tedgui A, and Mallat Z
- Subjects
- Animals, Apolipoproteins E genetics, Arteriosclerosis metabolism, Chemokine CCL2 blood, Cholesterol blood, Disease Progression, Femoral Artery, Ligation, Male, Mice, Mice, Inbred C57BL, Mice, Knockout, Safety, Treatment Failure, Vascular Endothelial Growth Factor A blood, Apolipoproteins E deficiency, Arteriosclerosis therapy, Bone Marrow Transplantation adverse effects, Hindlimb blood supply, Ischemia therapy, Neovascularization, Physiologic, Sinus of Valsalva pathology
- Abstract
Background: Bone marrow-derived mononuclear cells (BM-MNCs) enhance postischemic neovascularization, and their therapeutic use is currently under clinical investigation. We evaluated the safety of BM-MNC-based therapy in the setting of atherosclerosis., Methods and Results: Apolipoprotein E (apoE)-knockout (KO) mice were divided into 4 groups: 20 nonischemic mice receiving intravenous injection of either saline (n=10) or 10(6) BM-MNCs from wild-type animals (n=10) and 20 mice with arterial femoral ligature receiving intravenous injection of either saline (n=10) or 10(6) BM-MNCs from wild-type animals (n=10) at the time of ischemia induction. Animals were monitored for 4 additional weeks. Atherosclerosis was evaluated in the aortic sinus. BM-MNC transplantation improved tissue neovascularization in ischemic hind limbs, as revealed by the 210% increase in angiography score (P<0.0001), the 33% increase in capillary density (P=0.01), and the 65% increase in tissue Doppler perfusion score (P=0.0002). Hindlimb ischemia without BM-MNC transplantation or BM-MNC transplantation without ischemia did not affect atherosclerotic plaque size. However, transplantation of 10(6) BM-MNCs into apoE-KO mice with hindlimb ischemia induced a significant 48% to 72% increase in lesion size compared with the other 3 groups (P=0.0025), despite similar total cholesterol levels. Transplantation of 10(5) BM-MNCs produced similar results, whereas transplantation of 10(6) apoE-KO-derived BM-MNCs had neither proangiogenic nor proatherogenic effects. There was no difference in plaque composition between groups., Conclusions: BM-MNC therapy is unlikely to affect atherosclerotic plaque stability in the short term. However, it may promote further atherosclerotic plaque progression in an ischemic setting.
- Published
- 2003
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144. Inhibition of K562 leukemia angiogenesis and growth by expression of antisense vascular endothelial growth factor (VEGF) sequence.
- Author
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He R, Liu B, Yang C, Yang RC, Tobelem G, and Han ZC
- Subjects
- Cell Line, Tumor, Down-Regulation, Genetic Vectors, Humans, Vascular Endothelial Growth Factor A pharmacology, Cell Survival, DNA, Antisense, Genetic Therapy, Leukemia, Erythroblastic, Acute pathology, Neovascularization, Pathologic, Vascular Endothelial Growth Factor A biosynthesis, Vascular Endothelial Growth Factor A genetics
- Abstract
Vascular endothelial growth factor (VEGF), a major angiogenic factor, plays a key role in the growth of solid tumor. Recently, expression of VEGF and its receptors has been found on leukemic cells as well as on endothelial cells. VEGF may fulfill a fundamental role in promoting tumor angiogenesis and proliferation by stimulating both endothelial cells and leukemic cells. To investigate the role of VEGF in the angiogenesis and growth of leukemic cell, we used an antisense strategy to downregulate VEGF expression in K562 cells, a human erythroleukemia cell line. Expression of antisense-VEGF in K562 cells reduced the secretion of VEGF protein and inhibited cell survival. The proliferation and migration of human umbilical vein endothelial cells were decreased in response to the conditioned medium (CM) from K562 cells expressed antisense-VEGF, compared to CM from K562 cells transfected with vector control. Moreover, subcutaneous injection of nude mice with antisense-VEGF K562 cells inhibited tumor growth with a reduction of the density of microvessels and an increased apoptosis in those tumors, compared to vector control K562 cells. These results suggest that the efficient downregulation of the VEGF production in leukemic cells using antisense-VEGF may constitute a novel strategy of treatment in leukemia.
- Published
- 2003
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145. Suppression of tumor growth by viral vector-mediated gene transfer of N-terminal truncated platelet factor 4.
- Author
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Li Y, Jin Y, Chen H, Jie G, Tobelem G, Caen JP, and Han ZC
- Subjects
- Animals, Disease Models, Animal, Disease Progression, Female, Humans, Mice, Mice, Inbred BALB C, Neoplasm Transplantation pathology, Neoplasms blood supply, Neoplasms genetics, Neoplasms therapy, Neovascularization, Pathologic drug therapy, Survival Rate, Genetic Therapy methods, Genetic Vectors genetics, Neoplasms pathology, Platelet Factor 4 genetics, Platelet Factor 4 therapeutic use, Retroviridae genetics
- Abstract
Platelet factor four (PF4), an inhibitor of endothelial cell proliferation in vitro, inhibits angiogenesis and tumor growth in vivo in experimental animals. The present study was designed to determine whether gene therapy-mediated expression of a form of PF4 lacking 16 amino acids of N-terminus from tumor cells could inhibit angiogenesis and tumor growth in vivo. Two replication-defective recombinant retroviral vectors were constructed. One encodes human PF4 (rRV-PF4) and the other encodes the N-truncated peptide (rRVp17-70). These vectors were then used to transduce KB cells, a human head and neck squamous carcinoma cell line. Expression of PF4 and p17-70 transgenes was confirmed by Western blot analysis. In vitro, both rRV-PF4 and rRVp17-70 were able to inhibit selectively the proliferation of human umbilical vascular endothelial cells (HUVEC) but not KB cells. In vivo activity was assessed by injecting 10(7) KB cells subcutaneously into nude mice and by monitoring subsequent tumor growth, xenograft vascular histochemistry, and animal survival. Viral vector-mediated cDNA transfer of PF4 and p17-70 resulted in inhibiting solid tumors through an anti-angiogenic action in vivo. Our data indicate that targeting tumor angiogenesis using viral-mediated gene transfer of full-length and N-terminal truncated PF4 represents a promising strategy for cancer gene therapy.
- Published
- 2003
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146. The N-terminal domain of hepatocyte growth factor inhibits the angiogenic behavior of endothelial cells independently from binding to the c-met receptor.
- Author
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Merkulova-Rainon T, England P, Ding S, Demerens C, and Tobelem G
- Subjects
- Cell Division drug effects, Cell Movement drug effects, Cells, Cultured, Glycosaminoglycans metabolism, Heparin metabolism, Humans, Proto-Oncogene Mas, Recombinant Proteins pharmacology, Structure-Activity Relationship, Surface Plasmon Resonance, Angiogenesis Inhibitors pharmacology, Endothelium, Vascular cytology, Hepatocyte Growth Factor chemistry, Hepatocyte Growth Factor physiology, Proto-Oncogene Proteins c-met metabolism
- Abstract
Hepatocyte growth factor (HGF) is a pleiotropic factor that plays an important role in complex biological processes such as embryogenesis, tissue regeneration, cancerogenesis, and angiogenesis. HGF promotes cell proliferation, survival, motility, and morphogenesis through binding to its receptor, a transmembrane tyrosine kinase encoded by the MET proto-oncogene (c-met). Structurally speaking, HGF is a polypeptide related to the enzymes of the blood coagulation cascade. Thus, it comprises kringle domains that in some other proteins have been shown to be responsible for the anti-angiogenic activity. To check whether the isolated kringles of HGF were able to inhibit angiogenesis, we produced them as recombinant proteins and compared their biological activity with that of the recombinant HGF N-terminal domain (N). We showed that (i) none of the isolated HGF kringle exhibits an anti-angiogenic activity; (ii) N is a new anti-angiogenic polypeptide; (iii) the inhibitory action of N is not specific toward HGF, because it antagonized the angiogenic activity of other growth factors, such as fibroblast growth factor-2 and vascular endothelial growth factor; and (iv) in contrast with full-length HGF, N does not bind to the c-met receptor in vitro, but fully retains its heparin-binding capacity. Our results suggest that N inhibits angiogenesis not by disrupting the HGF/c-met interaction but rather by interfering with the endothelial glycosaminoglycans, which are the secondary binding sites of HGF.
- Published
- 2003
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147. Adenovirus-mediated gene therapy with an antiangiogenic fragment of thrombospondin-1 inhibits human leukemia xenograft growth in nude mice.
- Author
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Liu P, Wang Y, Li YH, Yang C, Zhou YL, Li B, Lu SH, Yang RC, Cai YL, Tobelem G, Caen J, and Han ZC
- Subjects
- Adenoviridae genetics, Angiogenesis Inhibitors genetics, Angiogenesis Inhibitors pharmacology, Animals, Cell Division drug effects, Female, Genetic Vectors, Humans, K562 Cells, Mice, Mice, Nude, Neovascularization, Pathologic drug therapy, Peptide Fragments administration & dosage, Peptide Fragments genetics, Peptide Fragments pharmacology, Thrombospondin 1 genetics, Thrombospondin 1 pharmacology, Transduction, Genetic, Transplantation, Heterologous, Treatment Outcome, Angiogenesis Inhibitors administration & dosage, Genetic Therapy methods, Leukemia therapy, Thrombospondin 1 administration & dosage
- Abstract
Recent investigations support the idea that angiogenesis is involved in the pathophysiology of leukemia. Within a given microenvironment, the angiogenic response is regulated by a delicate balance of angiogenesis inducers and inhibitors. Thrombospondin-1 (TSP-1) is a multifunctional extracellular glycoprotein showing angiostatic properties in multiple in vitro and in vivo assays. Interestingly, there is also proangiogenic domain in this complex molecule. Development of TSP-1 as an antiangiogenic drug has been hindered by multiplicity of its functional effects, difficulties in its production and its poor pharmacokinetics. The aim of the present study was to establish a recombinant adenovirus (ADV.TSP-1(f)) expressing antiangiogenic fragment of TSP-1 (TSP-1(f)), and to determine the feasibility for use of the adenovirally expressed TSP-1(f) in leukemia gene therapy. The results of this investigation showed that TSP-1(f) was expressed efficiently in adenovirus-transduced human myelogenous leukemia K562 cells. Compared to the controls, although there was almost no effect on proliferation of K562 cells in vitro, adenovirus-mediated TSP-1(f) transduction inhibited the growth of K562 xenografts dramatically. Furthermore, the microvessel density (MVD) was much lower in the ADV.TSP-1(f)-treated tumors compared to the controls. These data support the use of in vivo gene delivery approach to produce antiangiogenic fragment of TSP-1 for leukemia therapy.
- Published
- 2003
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148. [Mechanisms and role of lymphangiogenesis in cancer metastasis].
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Dupuy E and Tobelem G
- Subjects
- Cell Culture Techniques methods, Endothelial Growth Factors genetics, Growth Substances physiology, Humans, Intercellular Signaling Peptides and Proteins genetics, Lymphokines genetics, Mutation, Tumor Cells, Cultured, Vascular Endothelial Growth Factor A, Vascular Endothelial Growth Factors, Endothelial Growth Factors physiology, Intercellular Signaling Peptides and Proteins physiology, Lymph Nodes growth & development, Lymphatic Metastasis physiopathology, Lymphokines physiology
- Abstract
An important critical point in tumor progression is the acquisition of metastatic potential. The presence of metastases in regional lymph nodes is an indicator of poor survival. The vascular endothelial growth factor (VEGF) family of growth factors and receptors is involved in vasculogenesis and angiogenesis. Among them, VEGF-C and VEGF-D regulate the lymphatic vessels development and growth via their binding to their receptor VEGFR3. The expression of VEGF-C or VEGF-D is demonstrated in various human tumors and can be used as pronostic factors in some of them. With the aid of these molecules and the discovery of specific lymphatic markers, lymphatic endothelial cells can be isolated and lymphatic vessels can be identified within tumors. The role of lymphangiogenesis in promoting the metastatic spread of tumor cells has been studied in animal models., (Copyright John Libbey Eurotext 2003.)
- Published
- 2003
149. HGF receptor up-regulation contributes to the angiogenic phenotype of human endothelial cells and promotes angiogenesis in vitro.
- Author
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Ding S, Merkulova-Rainon T, Han ZC, and Tobelem G
- Subjects
- Antibodies pharmacology, Antigens, CD, Blotting, Western, Cadherins analysis, Cadherins genetics, Cell Count, Cell Division, Cell Movement, Cells, Cultured, Collagen, Culture Media, Endothelium, Vascular ultrastructure, Fluorescent Antibody Technique, Hepatocyte Growth Factor pharmacology, Humans, Immunohistochemistry, Intercellular Junctions chemistry, Kinetics, Morphogenesis, Phenotype, Proto-Oncogene Proteins c-met analysis, Proto-Oncogene Proteins c-met genetics, Proto-Oncogene Proteins c-met immunology, RNA, Messenger analysis, Reverse Transcriptase Polymerase Chain Reaction, Umbilical Veins, Wound Healing, Endothelium, Vascular chemistry, Neovascularization, Physiologic, Proto-Oncogene Proteins c-met physiology
- Abstract
Hepatocyte growth factor (HGF) is a mesenchyme-derived pleiotropic growth factor and a powerful stimulator of angiogenesis, which acts on cells by binding to the c-met receptor. The exact role of the endogenous HGF/c-met system in one or more steps of the angiogenic process is not completely understood. To contribute to this question we used immunocytochemical analysis, Western blotting, and reverse transcription-polymerase chain reaction to study the expression of c-met in endothelial cells cultured in different growth conditions. We found that c-met is not colocalized with vascular endothelial (VE)-cadherin in cell-cell junctions. c-met and VE-cadherin were shown to be inversely regulated by cell density, at both the protein and the mRNA levels. We established that c-met is up-regulated during the in vitro recapitulation of several steps of angiogenesis. The c-met expression was increased shortly after switching to angiogenic growth conditions and remained high during the very first steps of angiogenesis, including cell migration, and cell proliferation. The endothelial cells in which the expression of c-met was up-regulated were more responsive to HGF and exhibited a higher rate of morphogenesis. Moreover, the antibody directed against the extracellular domain of the c-met inhibited angiogenesis in vitro. Our results suggest that c-met is a marker of angiogenic phenotype for endothelial cells and represents an attractive target for the development of new antiangiogenic therapies.
- Published
- 2003
- Full Text
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150. Tumoral angiogenesis and tissue factor expression during hepatocellular carcinoma progression in a transgenic mouse model.
- Author
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Dupuy E, Hainaud P, Villemain A, Bodevin-Phèdre E, Brouland JP, Briand P, and Tobelem G
- Subjects
- Animals, Carcinoma, Hepatocellular metabolism, Disease Progression, Female, Hypoxia-Inducible Factor 1, alpha Subunit, Liver Neoplasms metabolism, Male, Mice, Mice, Transgenic, Platelet Activation, RNA, Messenger metabolism, Tissue Distribution, Transcription Factors genetics, Vascular Endothelial Growth Factor A genetics, Carcinoma, Hepatocellular blood supply, Carcinoma, Hepatocellular pathology, Liver Neoplasms blood supply, Liver Neoplasms pathology, Neovascularization, Pathologic blood, Neovascularization, Pathologic metabolism, Thromboplastin metabolism
- Abstract
Background/aims: The hypervascularity described in hepatocellular carcinoma varies according to the progression and the differentiation of the tumor, suggesting an angiogenic switch during tumor development., Methods: We used a transgenic mouse model of hepatocellular carcinoma induced by the expression of SV40-T antigen, in which male mice developed hepatic tumors at various temporal and histological stages, whereas female mice remained tumor-free. We analyzed, by immunostaining and reverse transcription-polymerase chain reaction, factors involved in tumoral angiogenesis., Results: We demonstrated that tumoral angiogenesis occurred before the development of diffuse hepatocarcinoma. We showed that some SV40-T-positive cells with an endothelial phenotype are involved in angiogenic processes, suggesting a partial vasculogenic mimicry. This tumoral angiogenesis is associated with platelet activation due to tissue factor expression in endothelial cells and invading macrophages. Normal and transgenic livers exhibited different pattern of expression of hypoxia-inducible factor 1 alpha (HIF-1alpha) and vascular endothelial growth factor (VEGF) mRNA., Conclusions: This model of hepatocellular carcinoma displays marked tumoral angiogenesis, with proliferation, remodeling and arterialization of hepatic sinusoids, probably associated with a partial vasculogenic mimicry. Abnormal angiogenesis observed in hepatocarcinoma was associated with platelet activation by tissue factor (TF) produced by endothelial cells and invading macrophages. In this transgenic model, HIF-1alpha, VEGF, and TF play a crucial role in tumoral angiogenesis.
- Published
- 2003
- Full Text
- View/download PDF
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