Role of delta-like-4/Notch in the formation and wiring of the lymphatic network in zebrafish.
; ; et al
in Arteriosclerosis, Thrombosis, and Vascular Biology (2010), 30(9), 1695-702
OBJECTIVE: To study whether Notch signaling, which regulates cell fate decisions and vessel morphogenesis, controls lymphatic development. METHODS AND RESULTS: In zebrafish embryos, sprouts from the axial ... [more ▼]
OBJECTIVE: To study whether Notch signaling, which regulates cell fate decisions and vessel morphogenesis, controls lymphatic development. METHODS AND RESULTS: In zebrafish embryos, sprouts from the axial vein have lymphangiogenic potential because they give rise to the first lymphatics. Knockdown of delta-like-4 (Dll4) or its receptors Notch-1b or Notch-6 in zebrafish impaired lymphangiogenesis. Dll4/Notch silencing reduced the number of sprouts producing the string of parchordal lymphangioblasts; instead, sprouts connecting to the intersomitic vessels were formed. At a later phase, Notch silencing impaired navigation of lymphatic intersomitic vessels along their arterial templates. CONCLUSIONS: These studies imply critical roles for Notch signaling in the formation and wiring of the lymphatic network. [less ▲]Detailed reference viewed: 5 (3 ULg)
Does plasminogen activator inhibitor-1 drive lymphangiogenesis?
; ; Blacher, Silvia et al
in PLoS ONE (2010), 5(3), 9653
The purpose of this study is to explore the function of plasminogen activator inhibitor-1 (PAI-1) during pathological lymphangiogenesis. PAI-1, the main physiological inhibitor of plasminogen activators ... [more ▼]
The purpose of this study is to explore the function of plasminogen activator inhibitor-1 (PAI-1) during pathological lymphangiogenesis. PAI-1, the main physiological inhibitor of plasminogen activators is involved in pathological angiogenesis at least by controlling extracellular proteolysis and by regulating endothelial cell survival and migration. Protease system's role in lymphangiogenesis is unknown yet. Thus, based on its important pro-angiogenic effect, we hypothesized that PAI-1 may regulate lymphangiogenesis associated at least with metastatic dissemination of cancer cells. To address this issue, we studied the impact of PAI-1 deficiency in various murine models of tumoral lymphangiogenesis. Wild-type PAI-1 proficient mice were used as controls. We provide for the first time evidence that PAI-1 is dispensable for tumoral lymphangiogenesis associated with breast cancers either induced by mammary carcinoma cell injection or spontaneously appearing in transgenic mice expressing the polyomavirus middle T antigen (PymT) under the control of a mouse mammary tumor virus long-terminal repeat promoter (MMTV-LTR). We also investigated inflammation-related lymphatic vessel recruitment by using two inflammatory models. PAI-1 deficiency did neither affect the development of lymphangioma nor burn-induced corneal lymphangiogenesis. These novel data suggest that vascular remodelling associated with lymphangiogenesis and angiogenesis involve different molecular determinants. PAI-1 does not appear as a potential therapeutic target to counteract pathological lymphangiogenesis. [less ▲]Detailed reference viewed: 81 (22 ULg)
Soluble forms of VEGF receptor-1 and -2 promote vascular maturation via mural cell recruitment.
LORQUET, Sophie ; ; Blacher, Silvia et al
in FASEB Journal (2010), 24(10), 3782-95
Two soluble forms of vascular endothelial growth factor (VEGF) receptors, sVEGFR-1 and sVEGFR-2, are physiologically released and overproduced in some pathologies. They are known to act as anti-VEGF ... [more ▼]
Two soluble forms of vascular endothelial growth factor (VEGF) receptors, sVEGFR-1 and sVEGFR-2, are physiologically released and overproduced in some pathologies. They are known to act as anti-VEGF agents. Here, we report that these soluble receptors contribute to vessel maturation by mediating a dialogue between endothelial cells (EC) and mural cells that leads to blood vessel stabilization. Through a multidisciplinary approach, we provide evidences that these soluble VEGF receptors promote mural cell migration through a paracrine mechanism involving interplay in EC between VEGF/VEGFR-2 and sphingosine-1- phosphate type-1 (S1P)/S1P1 pathways that leads to endothelial nitric oxyde synthase (eNOS) activation. This new paradigm is supported by the finding that sVEGFR-1 and -2: 1) induce an eNOS-dependent outgrowth of a mural cell network in an ex vivo model of angiogenesis, 2) increase the mural cell coverage of neovessels in vitro and in vivo, 3) promote mural cell migration towards EC, 4) stimulate endothelial S1P1 overproduction and eNOS activation that promote the migration and the recruitment of neighboring mural cells. These findings provide new insights into mechanisms regulating physiological and pathological angiogenesis and vessel stabilization. [less ▲]Detailed reference viewed: 144 (44 ULg)
Higher sensitivity of Adamts12-deficient mice to tumor growth and angiogenesis.
El Hour, Mehdi ; ; Blacher, Silvia et al
in Oncogene (2010), 29(20), 3025-32
ADAMTS (a disintegrin and metalloproteinase domain with thrombospondin motifs) constitute a family of endopeptidases related to matrix metalloproteinases. These proteases have been largely implicated in ... [more ▼]
ADAMTS (a disintegrin and metalloproteinase domain with thrombospondin motifs) constitute a family of endopeptidases related to matrix metalloproteinases. These proteases have been largely implicated in tissue remodeling and angiogenesis associated with physiological and pathological processes. To elucidate the in vivo functions of ADAMTS-12, we have generated a knockout mouse strain (Adamts12−/−) in which Adamts12 gene was deleted. The mutant mice had normal gestations and no apparent defects in growth, life span and fertility. By applying three different in vivo models of angiogenesis (malignant keratinocyte transplantation, Matrigel plug and aortic ring assays) to Adamts12−/− mice, we provide evidence for a protective effect of this host enzyme toward angiogenesis and cancer progression. In the absence of Adamts-12, both the angiogenic response and tumor invasion into host tissue were increased. Complementing results were obtained by using medium conditioned by cells overexpressing human ADAMTS-12, which inhibited vessel outgrowth in the aortic ring assay. This angioinhibitory effect of ADAMTS-12 was independent of its enzymatic activity as a mutated inactive form of the enzyme was similarly efficient in inhibiting endothelial cell sprouting in the aortic ring assay than the wild-type form. Altogether, our results show that ADAMTS-12 displays antiangiogenic properties and protect the host toward tumor progression. [less ▲]Detailed reference viewed: 140 (36 ULg)
Lymphangiogenesis: in vitro and in vivo models
; Noël, Agnès
in FASEB Journal (2010), 24(1), 8-21
Lymphangiogenesis, the formation of new lymphatic vessels from preexisting ones, is an important biological process associated with diverse pathologies, such as metastatic dissemination and graft ... [more ▼]
Lymphangiogenesis, the formation of new lymphatic vessels from preexisting ones, is an important biological process associated with diverse pathologies, such as metastatic dissemination and graft rejection. In addition, lymphatic hypoplasia characterizes lymphedema, usually a progressive and lifelong condition for which no curative treatment exists. Much progress has been made in recent years in identifying molecules specifically expressed on lymphatic vessels and in the setting up of in vitro and in vivo models of lymphangiogenesis. These new tools rapidly provided an abundance of information on the mechanisms underlying lymphatic development and the progression of diseases associated with lymphatic dysfunction. In this review, we describe the common in vitro and in vivo models of lymphangiogenesis that have proven suitable for investigating lymphatic biology and the interactions occurring between lymphatic vessels and other cells, such as immune cells and cancer cells. Their rationales and limitations are discussed and illustrated by the most informative findings obtained with them. [less ▲]Detailed reference viewed: 98 (17 ULg)
Membrane type 1 matrix metalloproteinase detection in tumors, using the iodinated endogenous [123I]-tissue inhibitor 2 of metalloproteinases as imaging agent.
; ; et al
in Cancer Biotherapy & Radiopharmaceuticals (2010), 25(5), 511-20
Matrix metalloproteinases (MMPs) are principal participants in tumor development. In addition to serve as a useful biochemical marker, MMP expression may also provide a target for the diagnostic in vivo ... [more ▼]
Matrix metalloproteinases (MMPs) are principal participants in tumor development. In addition to serve as a useful biochemical marker, MMP expression may also provide a target for the diagnostic in vivo imaging of tumors, using a radiolabeled inhibitor. This study investigates the use of membrane type 1 (MT1)-MMP as target for in vivo tumor diagnosis. Specific binding of the endogenous tissue inhibitor of metalloproteinase-2 (TIMP-2) to MT1-MMP has been previously described. In this study, biodistribution and imaging experiments were performed on MT1-MMP-overexpressing (S.1.5) and control (C.IV.3) tumor-inoculated mice using [(123)I]-recombinant human TIMP-2 (rhTIMP-2) as radioligand and [(123)I]-rhTIMP-1 as control. The expression profile was controlled in vitro and on tumor extracts. rhTIMP-2 as well as rhTIMP-1 were labeled using the Iodogen method and characterized. Biodistribution of [(123)I]-rhTIMP-2 showed a tumor uptake of 2.87% +/- 1.58% ID/g at 3 hours postinjection in S.1.5. Tumor values of [(123)I]-rhTIMP-1 and [(123)I]-rhTIMP-2 evaluated in S.1.5 and C.IV.3, respectively, were significantly lower. Planar imaging revealed significant uptake of [(123)I]-rhTIMP-2 in S.1.5 compared with contralateral background areas. This could not be observed in C.IV.3 and with [(123)I]-rhTIMP-1 in S.1.5. All tumors were well established (200-800 mg). These results suggest that rhTIMP-2 holds potential for development of radiotracers for in vivo imaging in overexpressing MT1-MMP but not in similar tumors that do not express this protease. [less ▲]Detailed reference viewed: 19 (5 ULg)
TIMP-2 binding with cellular MT1-MMP stimulates invasion-promoting MEK/ERK signaling in cancer cells
Sounni, Nor Eddine ; ; et al
in International Journal of Cancer = Journal International du Cancer (2010), 126(5), 1067-78
Both invasion-promoting MT1-MMP and its physiological inhibitorTIMP-2 play a significant role in tumorigenesis and are identified in the most aggressive cancers. Despite its antiproteolytic effects in ... [more ▼]
Both invasion-promoting MT1-MMP and its physiological inhibitorTIMP-2 play a significant role in tumorigenesis and are identified in the most aggressive cancers. Despite its antiproteolytic effects in vitro, clinical data suggest that TIMP-2 expression is positively associated with tumor recurrence, thus emphasizing the wide-ranging role of TIMP-2 in malignancies. To shed light on this role of TIMP-2, we report that low concentrations of TIMP-2, by interacting with MT1-MMP (a specific membrane receptor of TIMP-2), induce the MEK/ERK signaling cascade in fibrosarcoma HT1080 cells which express MT1-MMP naturally. TIMP-2 binding with cell surface-associated MT1-MMP stimulates phosphorylation of MEK1/2, which is upstream of ERK1/2, and the ERK1/2 substrate p90RSK. Consistent with volumes of literature, we confirmed that the activation of ERK stimulated cell migration. Both the transcriptional silencing of MT1-MMP and the inhibition of MEK1/2 reversed the signaling effects of TIMP-2/MT1-MMP while the active site-targeting MMP inhibitor GM6001 did not. Our data suggest that both the interactions of TIMP-2 with MT1-MMP, which activate the pro-migratory ERK signaling cascade, and the conventional inhibition of MT1-MMP's catalytic activity by TIMP-2, play a role in the invasion-promoting function of MT1-MMP. The TIMP-2-induced stimulation of ERK signaling in cancer cells explains the direct, as opposed to the inverse, association of TIMP-2 expression with poor prognosis in cancer. [less ▲]Detailed reference viewed: 57 (9 ULg)
Histological and transcriptional study of angiogenesis and lymphangiogenesis in uninvolved skin, acute pinpoint lesions and established psoriasis plaques: an approach of vascular development chronology in psoriasis
Henno, Audrey ; Blacher, Silvia ; Lambert, Charles et al
in Journal of Dermatological Science (2010), 57(3), 162-169
Background Dysregulation of angiogenesis and lymphangiogenesis could participate in psoriasis pathogenesis. Analysis of nascent psoriasis lesions should help at identifying early vascular anomalies ... [more ▼]
Background Dysregulation of angiogenesis and lymphangiogenesis could participate in psoriasis pathogenesis. Analysis of nascent psoriasis lesions should help at identifying early vascular anomalies. Objective To analyse vascular development, angiogenesis and lymphangiogenesis markers expression in uninvolved skin in psoriatic patients (N), early psoriasis lesions or pinpoints (PP) and psoriasis plaques (PSO). Methods Skin biopsies were taken in 17 patients in N and in PSO and/or PP. The mRNA steady-state level of angiogenesis and lymphangiogenesis markers was measured by RT-PCR. Immunohistochemistry was performed for von Willebrand factor, podoplanin, Ki-67 and VEGFR3. Blood (BV) and lymphatic (LV) vessels expansion was measured by computer-assisted morphometry. Results Clinical and epidermal aspects indicated that PP are intermediate between N and PSO. While total BV area was already increased in PP similarly to PSO as compared to N, LV area in PP was intermediate between N and PSO. Mean LV size was identical in N and PP and increased in PSO, mean BV size in PP being intermediate between N and PSO. VEGF-A 189 variant was increased in PP as compared to N and PSO. As compared to N, angiogenesis markers (VEGF-A isoforms, PlGF, VEGFR2, NRP-1), VEGF-C and NRP-2 were similarly increased in PP and PSO. Keratin 16 and the lymphangiogenesis markers (VEGFR3, prox-1) were intermediate in PP. Conclusion These data suggest that the expansion of lymphatic vessels occurs after blood vascular development in psoriasis. Expansion of BV in PP could be followed by vessel enlargement during progression to PSO, in parallel with a decreased VEGF-A 189/VEGF-A 121 balance in plaques [less ▲]Detailed reference viewed: 61 (6 ULg)
Further pharmacological and genetic evidence for the efficacy of PlGF inhibition in cancer and eye disease.
; ; et al
in Cell (2010), 141(1), 178-90
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 ... [more ▼]
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. [less ▲]Detailed reference viewed: 125 (10 ULg)
Effects of HPV-16 E5, E6 and E7 Proteins on Survival, Adhesion, Migration and Invasion of Trophoblastic Cells
; ; et al
in Carcinogenesis (2010), 31(3), 473-80
Amongst high-risk human papillomaviruses (HPV), HPV-16 infection is the most prevalent causative factor for cervical cancer. Beside other mucosal targets, HPV-16 was reported to infect the placenta and to ... [more ▼]
Amongst high-risk human papillomaviruses (HPV), HPV-16 infection is the most prevalent causative factor for cervical cancer. Beside other mucosal targets, HPV-16 was reported to infect the placenta and to replicate in trophoblastic cells. Since these cells share invasive properties of tumoral cells, they represent an ideal model to investigate several oncogenic processes. In the present work, we analyzed the impacts of HPV-16 E5, E6 and E7 oncoproteins on the trophoblastic model. Our results showed that E5 impaired the viability of trophoblastic and cervical cell lines but E6 and E7, favouring cell growth, neutralised the E5 cytotoxic effect. In addition, E5 decreased the adhesiveness of trophoblastic cells to the tissue culture plastic and to endometrial cells similarly as previously described for E6 and E7. E5 and E6 plus E7 increased also their migration and their invasive properties. Cells expressing HPV-16 early proteins under the control of the LCR endogenous promoter displayed growth advantage and were also more motile and invasive compared to control cells. Interestingly, the E-cadherin was down regulated in trophoblastic cells expressing E5, E6 and E7. NF-kB and AP-1 activities were also enhanced. In conclusion, HPV-16 early proteins enhanced trophoblastic growth and intensify the malignant phenotype by impairing cell adhesion leading to increased cellular motile and invasive properties. HPV-16 E5 participated, with E6 and E7, in these changes by impairing Ecadherin expression, a hallmark of malignant progression. [less ▲]Detailed reference viewed: 60 (6 ULg)
New Biological Investigations on 3-Bromophenyl 6-Acetoxymethyl-2-oxo-2H-1-Benzopyran-3-Carboxylate as Anti-angiogenic Agent
; ; De Tullio, Pascal et al
in Drug Development Research (2010), 71
The development of blood vessels inside tumors is required to provide the nutrients and oxygen needed for tumor growth and to allow the spread of cancer cells at a distance to form metastasis ... [more ▼]
The development of blood vessels inside tumors is required to provide the nutrients and oxygen needed for tumor growth and to allow the spread of cancer cells at a distance to form metastasis. Angiogenesis is also implicated in ocular diseases like age-related macular degeneration. The present work describes the potential anti-angiogenic properties of a coumarinic derivative, 3-bromophenyl 6-acetoxymethyl-2-oxo-2H-1-benzopyran-3-carboxylate (IK9), previously described as a potent inhibitor of HT 1080 fibrosarcoma cell invasion in vitro and tumor growth in vivo. In vivo, ex vivo, and in vitro models were used to delineate the anti-angiogenic properties of IK9. The anti-angiogenic effect of IK9 was demonstrated in vivo in a choroidal neovascularization mice model and additionally ex vivo in a rat aortic ring assay where it was more active than the known matrix metalloproteinase inhibitor Ro 28-2653. IK9 did not affect apoptosis, proliferation, or endothelial cell invasiveness in vitro. These findings suggest a complex mechanism of action of the compound via direct or indirect effects on endothelial cell properties. This study identifies IK9 as a new potent inhibitor of angiogenesis and suggests its potential use as a therapeutic agent. [less ▲]Detailed reference viewed: 77 (14 ULg)
MMP-19 Deficiency Promotes Tenascin-C Accumulation and Allergen-induced Airway Inflammation.
Guéders, Maud ; ; Quesada Calvo, Florence et al
in American Journal of Respiratory Cell and Molecular Biology (2010), 43(3), 286-95
Matrix metalloproteinases (MMPs) recently appeared as key regulators of inflammation, allowing recruitment and clearance of inflammatory cells and modifying the biological activity of many peptidic ... [more ▼]
Matrix metalloproteinases (MMPs) recently appeared as key regulators of inflammation, allowing recruitment and clearance of inflammatory cells and modifying the biological activity of many peptidic mediators by cleavage. MMP-19 is a newly described MMP and preferentially cleaves matrix proteins such as collagens and tenascin-C. The role of MMP-19 in asthma has not been described to date. The purpose of the present study was to assess MMP-19 expression in a murine asthma model and to address biological effects of MMP-19 deficiency in mice. Allergenexposed wild-type (WT) mice displayed an increased expression of MMP-19 mRNA and an increased number of MMP-19-positive cells in the lungs detected by immunohistochemistry. After allergen challenge of MMP-19 knockout (MMP-19-/-) mice, an exacerbated eosinophilic inflammation was detected in bronchoalveolar lavage fluid and bronchial tissue along with an increased airway responsiveness to methacholine. A shift towards increased Th2-driven inflammation in MMP-19-/- mice was demonstrated by 1) increased numbers of cells expressing the IL-33 receptor T1/ST2 in lung parenchyma, 2) increased IgG1 levels in serum and 3) higher levels of IL-13 and CCL11 in lung extracts. Tenascin-C was found accumulated in peribronchial areas of MMP-19-/- after allergen challenges as assessed by Western blot and immunohistochemistry analysis. We conclude that MMP-19 is a new mediator in asthma, preventing tenascin-C accumulation and directly or indirectly controlling Th2-driven airway eosinophilia and airway hyperreactivity. Our data suggest that MMP-19 might act on Th2 inflammation homeostasis through preventing tenascin protein accumulation. [less ▲]Detailed reference viewed: 78 (19 ULg)
Conception, synthèse et évaluation biologique de dérivés coumariniques en tant qu’agents anti-cancéreux potentiels
Hemmer, Marc ; Bambi Nyanguile, Sylvie-Mireille ; De Tullio, Pascal et al
Poster (2009, May)Detailed reference viewed: 44 (20 ULg)
Conception, synthèse et évaluation biologique de dérivés coumariniques en tant qu’agents anti-cancéreux potentiels
; De Tullio, Pascal ; Konradowski, Erika et al
Conference (2009, February 03)Detailed reference viewed: 13 (6 ULg)
New asthma biomarkers: lessons from murine models of acute and chronic asthma.
Di Valentin, Emmanuel ; ; Garbacki, Nancy et al
in American Journal of Physiology - Lung Cellular and Molecular Physiology (2009), 296(2), 185-97
Many patients suffering from asthma are not fully controlled by currently available treatments, and some of them display an airway remodeling leading to exaggerated lung function decline. The aim of the ... [more ▼]
Many patients suffering from asthma are not fully controlled by currently available treatments, and some of them display an airway remodeling leading to exaggerated lung function decline. The aim of the present study was to unveil new mediators in asthma to better understand pathophysiology and propose or validate new potential therapeutic targets. A mouse model of asthma mimicking acute or chronic asthma disease was used to select genes undergoing a modulation in both acute and chronic conditions. Mice were exposed to ovalbumin or PBS for 1, 5, and 10 wk [short-, intermediate-, and long-term model (ST, IT, and LT)], and gene expression in the lung was studied using an Affymetrix 430 2.0 genome-wide microarray and further confirmed by RT-PCR and immunohistochemistry for selected targets. We report that 598, 1,406, and 117 genes were upregulated and 490, 153, 321 downregulated at ST, IT, and LT, respectively. Genes related to mucous secretion displayed a progressively amplified expression during the allergen exposure protocol, whereas genes corresponding to growth and differentiation factors, matrix metalloproteinases, and collagens were mainly upregulated at IT. By contrast, genes related to cell division were upregulated at ST and IT and were downregulated at LT. In this study, besides confirming that Arg1, Slc26a4, Ear11, and Mmp12 genes are highly modulated throughout the asthma pathology, we show for the first time that Agr2, Scin, and Cd209e genes are overexpressed throughout the allergen exposure and might therefore be considered as suitable new potential targets for the treatment of asthma. [less ▲]Detailed reference viewed: 164 (37 ULg)
USE OF CYCLODEXTRIN FOR TREATMENT AND PREVENTION OF BRONCHIAL INFLAMMATORY DISEASES.
Cataldo, Didier ; Evrard, Brigitte ; Foidart, Jean-Michel et al
Patent (2009)Detailed reference viewed: 57 (17 ULg)
Biomarker discovery in asthma-related inflammation and remodeling.
Quesada Calvo, Florence ; Fillet, Marianne ; De Seny, Dominique et al
in Proteomics (2009), 9(8), 2163-2170
Asthma is a complex inflammatory disease of airways. A network of reciprocal interactions between inflammatory cells, peptidic mediators, extracellular matrix components, and proteases is thought to be ... [more ▼]
Asthma is a complex inflammatory disease of airways. A network of reciprocal interactions between inflammatory cells, peptidic mediators, extracellular matrix components, and proteases is thought to be involved in the installation and maintenance of asthma-related airway inflammation and remodeling. To date, new proteic mediators displaying significant activity in the pathophysiology of asthma are still to be unveiled. The main objective of this study was to uncover potential target proteins by using surface-enhanced laser desorption/ionization-time of flight-mass spectrometry (SELDI-TOF-MS) on lung samples from mouse models of allergen-induced airway inflammation and remodeling. In this model, we pointed out several protein or peptide peaks that were preferentially expressed in diseased mice as compared to controls. We report the identification of different five proteins: found inflammatory zone 1 or RELM (FIZZ-1), calcyclin (S100A6), clara cell secretory protein 10 (CC10), Ubiquitin, and Histone H4. [less ▲]Detailed reference viewed: 245 (70 ULg)
Role of A Disintegrin and Metalloprotease-12 in Neutrophil Recruitment Induced by Airway Epithelium.
Rocks, Natacha ; ; Paulissen, Geneviève et al
in American Journal of Respiratory Cell and Molecular Biology (2009), 41(4), 449-58
Among proteases, metalloproteases are implicated in tissue remodeling, as shown in numerous diseases including allergy. ADAMs (A Disintegrin And Metalloprotease) metalloproteases are implicated in ... [more ▼]
Among proteases, metalloproteases are implicated in tissue remodeling, as shown in numerous diseases including allergy. ADAMs (A Disintegrin And Metalloprotease) metalloproteases are implicated in physiologic processes such as cytokine and growth factor shedding, cell migration, adhesion, or repulsion. Our aim was to measure ADAM-12 expression in airway epithelium and to define its role during the allergic response. To raise this question, we analyzed the ADAM-12 expression ex vivo after allergen exposure in patients with allergic rhinitis and in vitro in cultured primary human airway epithelial cells (AEC). Clones of BEAS-2B cells transfected with the full-length form of ADAM-12 were generated to study the consequences of ADAM-12 up-regulation on AEC function. After allergen challenge, a strong increase of ADAM-12 expression was observed in airway epithelium from patients with allergic rhinitis but not from control subjects. In contrast with the other HB-epidermal growth factor sheddases, ADAM-10 and -17, TNF-alpha in vitro increased the expression of ADAM-12 by AEC, an effect amplified by IL-4 and IL-13. Up-regulation of ADAM-12 in AEC increased the expression of alpha3 and alpha4 integrins and to the modulation of cell migration on fibronectin but not on collagen. Moreover, overexpression of ADAM-12 in BEAS-2B enhanced the secretion of CXCL1 and CXCL8 and their capacity to recruit neutrophils. CD47 was strongly decreased by ADAM-12 overexpression, a process associated with a reduced adhesion of neutrophils. These effects were mainly dependent on epidermal growth factor receptor activation. In summary, ADAM-12 is produced during allergic reaction by AEC and might increase neutrophil recruitment within airway mucosa. [less ▲]Detailed reference viewed: 70 (8 ULg)
Role of ADAM and ADAMTS metalloproteinases in airway diseases
Paulissen, Geneviève ; Rocks, Natacha ; Guéders, Maud et al
in Respiratory Research (2009), 10(1), 127
Lungs are exposed to the outside environment and therefore to toxic and infectious agents or allergens. This may lead to permanent activation of innate immune response elements. A Disintegrin And ... [more ▼]
Lungs are exposed to the outside environment and therefore to toxic and infectious agents or allergens. This may lead to permanent activation of innate immune response elements. A Disintegrin And Metalloproteinases (ADAMs) and ADAMs with Thrombospondin motifs (ADAMTS) are proteinases closely related to Matrix Metalloproteinases (MMPs). These multifaceted molecules bear metalloproteinase and disintegrin domains endowing them with features of both proteinases and adhesion molecules. Proteinases of the ADAM family are associated to various physiological and pathological processes and display a wide spectrum of biological effects encompassing cell fusion, cell adhesion, "shedding process", cleavage of various substrates from the extracellular matrix, growth factors or cytokines... This review will focus on the putative roles of ADAM/ADAMTS proteinases in airway diseases such as asthma and COPD. [less ▲]Detailed reference viewed: 130 (23 ULg)
VEGF-D deficiency in mice does not affect embryonic or postnatal lymphangiogenesis but reduces lymphatic metastasis.
; ; et al
in Journal of Pathology (The) (2009), 219(3), 356-364
Vascular endothelial growth factor-D (VEGF-D) is one of the two ligands of the VEGFR-3 receptor on lymphatic endothelial cells. Gene-silencing studies in mice and Xenopus tadpoles recently showed that the ... [more ▼]
Vascular endothelial growth factor-D (VEGF-D) is one of the two ligands of the VEGFR-3 receptor on lymphatic endothelial cells. Gene-silencing studies in mice and Xenopus tadpoles recently showed that the role of endogenous VEGF-D in lymphatic development is moderate. By contrast, exogenous VEGF-D is capable of stimulating lymphangiogenesis. Nonetheless, its endogenous role in pathological conditions remains largely unknown. Hence, we reassessed its role in disease, using Vegf-dnull mice. Vegf-dnull mice were generated that, under physiological conditions, displayed normal embryonic and postnatal lymphangiogenesis and lymphatic remodelling, efficient lymphatic functioning and normal health. Vegf-dnull mice also reponded normally in models of skin wound healing and healing of infarcted myocardium, despite enhanced expression of VEGF-D in these models in wild-type mice. In contrast, Vegf-dnull mice displayed reduced peritumoral lymphangiogenesis and lymph node metastasis in an orthotopic pancreatic tumour model. Together, our data indicate that endogenous VEGF-D in mice is dispensible for lymphangiogenesis during development, in postnatal and adult physiology and in several pathological conditions, but significantly contributes to lymphatic metastasis. [less ▲]Detailed reference viewed: 71 (3 ULg)