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Stephane Brezillon - One of the best experts on this subject based on the ideXlab platform.
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evaluation of Lumican effects on morphology of invading breast cancer cells expression of integrins and downstream signaling
FEBS Journal, 2020Co-Authors: Stephane Brezillon, Konstantina Karamanou, M Franchi, Maurizio Onisto, Alberto Passi, Demitrios H VyniosAbstract:: The small leucine-rich proteoglycan (SLRP) Lumican regulates estrogen receptors (ERs)-associated functional properties of breast cancer cells, expression of matrix macromolecules and epithelial-to-mesenchymal transition. However, it is not known whether the ER-dependent Lumican effects on breast cancer cells are related to the expression of integrins and their intracellular signaling pathways. Here, we analysed the effects of Lumican in three breast cancer cell lines: the highly metastatic ERβ-positive MDA-MB-231, cells with the respective ERβ suppressed (shERβMDA-MB-231) and lowly invasive ERα-positive MCF-7/c breast cancer cells. Scanning electron microscopy, confocal microscopy, real time PCR, Western blot, and cell adhesion assays were performed. Lumican effects on breast cancer cell morphology were also investigated in 3-dimensional collagen cultures. Lumican treatment induced cell-cell contacts, cell grouping and inhibited microvesicles and microvilli formation. The expression of the cell surface adhesion receptor CD44, its isoform and variants, hyaluronan (HA) and HA synthases were also investigated. Lumican inhibited the expression of CD44 and HA synthases and its effect on cell adhesion revealed a major role of α1, α2, α3, αVβ3, αVβ5 integrins in MDA-MB-231 cells, but not in MCF-7/c cells. Lumican upregulated the expression of α2 and β1 integrin subunits both in MDA-MB-231 and shERβMDA-MB-231 as compared to MCF-7/c cells. Downstream signaling pathways for integrins, such as FAK, ERK 1/2 MAPK 42/44 and Akt, were found to be downregulated by Lumican. Our data shed light to the molecular mechanisms responsible for the anti-cancer activity of Lumican in invasive breast cancer.
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Lumican as a multivalent effector in wound healing
Advanced Drug Delivery Reviews, 2018Co-Authors: Konstantina Karamanou, Stephane Brezillon, Francoisxavier Maquart, Gwenn PerrotAbstract:Abstract Wound healing, a complex physiological process, is responsible for tissue repair after exposure to destructive stimuli, without resulting in complete functional regeneration. Injuries can be stromal or epithelial, and most cases of wound repair have been studied in the skin and cornea. Lumican, a small leucine-rich proteoglycan, is expressed in the extracellular matrices of several tissues, such as the cornea, cartilage, and skin. This molecule has been shown to regulate collagen fibrillogenesis, keratinocyte phenotypes, and corneal transparency modulation. Lumican is also involved in the extravasation of inflammatory cells and angiogenesis, which are both critical in stromal wound healing. Lumican is the only member of the small leucine-rich proteoglycan family expressed by the epithelia during wound healing. This review summarizes the importance of Lumican in wound healing and potential methods of Lumican drug delivery to target wound repair are discussed. The involvement of Lumican in corneal wound healing is described based on in vitro and in vivo models, with critical emphasis on its underlying mechanisms of action. Similarly, the expression and role of Lumican in the healing of other tissues are presented, with emphasis on skin wound healing. Overall, Lumican promotes normal wound repair and broadens new therapeutic perspectives for impaired wound healing.
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Lumican a new inhibitor of matrix metalloproteinase 14 activity
FEBS Letters, 2014Co-Authors: Katarzyna Pietraszek, Stephane Brezillon, Corinne Perreau, Francoisxavier Maquart, Aurore Chatroncolliet, Anna Jakubiakaugustyn, Hubert Krotkiewski, Yanusz WegrowskiAbstract:Abstract We previously showed that Lumican regulates MMP-14 expression. The aim of this study was to compare the effect of Lumican and decorin on MMP-14 activity. In contrast to decorin, the glycosylated form of Lumican was able to significantly decrease MMP-14 activity in B16F1 melanoma cells. Our results suggest that a direct interaction occurs between Lumican and MMP-14. Lumican behaves as a competitive inhibitor which leads to a complete blocking of the activity of MMP-14. It binds to the catalytic domain of MMP-14 with moderate affinity ( K D ∼ 275 nM). Lumican may protect collagen against MMP-14 proteolysis, thus influencing cell–matrix interaction in tumor progression.
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Lumican: A new inhibitor of matrix metalloproteinase‐14 activity
FEBS Letters, 2014Co-Authors: Katarzyna Pietraszek, Stephane Brezillon, Corinne Perreau, Francoisxavier Maquart, Hubert Krotkiewski, Aurore Chatron-colliet, Anna Jakubiak-augustyn, Yanusz WegrowskiAbstract:Abstract We previously showed that Lumican regulates MMP-14 expression. The aim of this study was to compare the effect of Lumican and decorin on MMP-14 activity. In contrast to decorin, the glycosylated form of Lumican was able to significantly decrease MMP-14 activity in B16F1 melanoma cells. Our results suggest that a direct interaction occurs between Lumican and MMP-14. Lumican behaves as a competitive inhibitor which leads to a complete blocking of the activity of MMP-14. It binds to the catalytic domain of MMP-14 with moderate affinity ( K D ∼ 275 nM). Lumican may protect collagen against MMP-14 proteolysis, thus influencing cell–matrix interaction in tumor progression.
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Lumican effects in the control of tumour progression and their links with metalloproteinases and integrins
FEBS Journal, 2013Co-Authors: Stephane Brezillon, Francoisxavier Maquart, Katarzyna Pietraszek, Yanusz WegrowskiAbstract:Lumican is a member of the small leucine-rich proteoglycan family. It is present in numerous extracellular matrices of different tissues, such as muscle, cartilage, and cornea. In skin, Lumican is present as a glycoprotein. It plays a critical role in collagen fibrillogenesis, as shown by knocking out of its gene in mice. A direct link between Lumican expression and melanoma progression and metastasis has been demonstrated. Lumican was shown to impede tumour cell migration and invasion by directly interacting with the α2β1 integrin. In addition, an active sequence of the Lumican core protein, called lumcorin, was identified as being responsible for inhibition of melanoma cell migration. Lumican was also shown to exert angiostatic properties by downregulating the proteolytic activity associated with endothelial cell membranes, particularly matrix metalloproteinase (MMP)-14 and MMP-9. Globally, Lumican appears to be a potent agent for inhibiting tumour progression rather than tumorigenesis. However, progressive changes in proteoglycans occur in the tumour environment. The complexity and diversity of proteoglycan structure might be responsible for a variety of functions that regulate cell behaviour. Through their core protein and their glycosaminoglycan chains, proteoglycans can interact with growth factors and chemokines. These interactions affect cell signalling, motility, adhesion, growth, and apoptosis. This review summarizes recent data concerning Lumican control of tumour progression in different cancers, with a particular focus on its interactions with MMPs and integrins. Its potential therapeutic implications are discussed.
Yanusz Wegrowski - One of the best experts on this subject based on the ideXlab platform.
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Lumican a new inhibitor of matrix metalloproteinase 14 activity
FEBS Letters, 2014Co-Authors: Katarzyna Pietraszek, Stephane Brezillon, Corinne Perreau, Francoisxavier Maquart, Aurore Chatroncolliet, Anna Jakubiakaugustyn, Hubert Krotkiewski, Yanusz WegrowskiAbstract:Abstract We previously showed that Lumican regulates MMP-14 expression. The aim of this study was to compare the effect of Lumican and decorin on MMP-14 activity. In contrast to decorin, the glycosylated form of Lumican was able to significantly decrease MMP-14 activity in B16F1 melanoma cells. Our results suggest that a direct interaction occurs between Lumican and MMP-14. Lumican behaves as a competitive inhibitor which leads to a complete blocking of the activity of MMP-14. It binds to the catalytic domain of MMP-14 with moderate affinity ( K D ∼ 275 nM). Lumican may protect collagen against MMP-14 proteolysis, thus influencing cell–matrix interaction in tumor progression.
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Lumican: A new inhibitor of matrix metalloproteinase‐14 activity
FEBS Letters, 2014Co-Authors: Katarzyna Pietraszek, Stephane Brezillon, Corinne Perreau, Francoisxavier Maquart, Hubert Krotkiewski, Aurore Chatron-colliet, Anna Jakubiak-augustyn, Yanusz WegrowskiAbstract:Abstract We previously showed that Lumican regulates MMP-14 expression. The aim of this study was to compare the effect of Lumican and decorin on MMP-14 activity. In contrast to decorin, the glycosylated form of Lumican was able to significantly decrease MMP-14 activity in B16F1 melanoma cells. Our results suggest that a direct interaction occurs between Lumican and MMP-14. Lumican behaves as a competitive inhibitor which leads to a complete blocking of the activity of MMP-14. It binds to the catalytic domain of MMP-14 with moderate affinity ( K D ∼ 275 nM). Lumican may protect collagen against MMP-14 proteolysis, thus influencing cell–matrix interaction in tumor progression.
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Lumican effects in the control of tumour progression and their links with metalloproteinases and integrins
FEBS Journal, 2013Co-Authors: Stephane Brezillon, Francoisxavier Maquart, Katarzyna Pietraszek, Yanusz WegrowskiAbstract:Lumican is a member of the small leucine-rich proteoglycan family. It is present in numerous extracellular matrices of different tissues, such as muscle, cartilage, and cornea. In skin, Lumican is present as a glycoprotein. It plays a critical role in collagen fibrillogenesis, as shown by knocking out of its gene in mice. A direct link between Lumican expression and melanoma progression and metastasis has been demonstrated. Lumican was shown to impede tumour cell migration and invasion by directly interacting with the α2β1 integrin. In addition, an active sequence of the Lumican core protein, called lumcorin, was identified as being responsible for inhibition of melanoma cell migration. Lumican was also shown to exert angiostatic properties by downregulating the proteolytic activity associated with endothelial cell membranes, particularly matrix metalloproteinase (MMP)-14 and MMP-9. Globally, Lumican appears to be a potent agent for inhibiting tumour progression rather than tumorigenesis. However, progressive changes in proteoglycans occur in the tumour environment. The complexity and diversity of proteoglycan structure might be responsible for a variety of functions that regulate cell behaviour. Through their core protein and their glycosaminoglycan chains, proteoglycans can interact with growth factors and chemokines. These interactions affect cell signalling, motility, adhesion, growth, and apoptosis. This review summarizes recent data concerning Lumican control of tumour progression in different cancers, with a particular focus on its interactions with MMPs and integrins. Its potential therapeutic implications are discussed.
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overexpression of Lumican affects the migration of human colon cancer cells through up regulation of gelsolin and filamentous actin reorganization
Experimental Cell Research, 2012Co-Authors: Agata Radwanska, Francoisxavier Maquart, Yanusz Wegrowski, Monika Litwin, Dorota Nowak, Dagmara Baczynska, Maria MalickablaszkiewiczAbstract:Abstract Cell migration is a multistep process initiated by extracellular matrix components that leads to cytoskeletal changes and formation of different protrusive structures at the cell periphery. Lumican, a small extracellular matrix leucine-rich proteoglycan, has been shown to inhibit human melanoma cell migration by binding to α2β1 integrin and affecting actin cytoskeleton organization. The aim of this study was to determine the effect of Lumican overexpression on the migration ability of human colon adenocarcinoma LS180 cells. The cells stably transfected with plasmid containing Lumican cDNA were characterized by the increased chemotactic migration measured on Transwell filters. Lumican-overexpressing cells presented the elevated filamentous to monomeric actin ratio and gelsolin up-regulation. This was accompanied by a distinct cytoskeletal actin rearrangement and gelsolin subcellular relocation, as observed under laser scaning confocal microscope. Moreover, LS180 cells overexpressing Lumican tend to form podosome-like structures as indicated by vinculin redistribution and its colocalization with gelsolin and actin at the submembrane region of the cells. In conclusion, the elevated level of Lumican secretion to extracellular space leads to actin cytoskeletal remodeling followed by an increase in migration capacity of human colon LS180 cells. These data suggest that Lumican expression and its presence in ECM has an impact on colon cancer cells motility and may modulate invasiveness of colon cancer.
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Lumican inhibits angiogenesis by interfering with α2β1 receptor activity and downregulating mmp 14 expression
Thrombosis Research, 2011Co-Authors: Jolanta Niewiarowska, Stephane Brezillon, Francoisxavier Maquart, Yanusz Wegrowski, Izabela Sacewiczhofman, Radoslaw Bednarek, Mariusz Malinowski, Magdalena Wiktorska, Czeslaw S CierniewskiAbstract:abstract Article history:Received 1 March 2011Received in revised form 18 May 2011Accepted 13 June 2011Available online 12 July 2011Keywords:LumicanAngiogenesisMetalloproteinasesIntegrinsMetastasis Introduction: Previous studies showed that Lumican, a small leucine-rich proteoglycan that binds to α2integrin I domain, is an efficient inhibitor of cell adhesion and migration. In this report, we tested its effect onangiogenesis in vitro and in vivo.Materials and methods: Effect of Lumican on angiogenesis was evaluated by in vitro capillary tube formationtest performed between Fibrin II Gels or in Matrigel™ and in vivo by Matrigel ™ plug assay in BALB/c mice.Changes in matrix metalloproteinases expression caused by Lumican were analyzed in endothelial cells byreal-time PCR, Western immunoblotting and gelatin zymography.Results: In unchallenged endothelial cells, Matrigel™ induced robust capillary morphogenesis. In contrast,tube formation was dramatically reduced by Lumican, and by siRNA to β1 integrin subunit mRNA but not bycontrol siRNA. Similarly, Lumican effectively inhibited neovascularization in vivo in assays using Matrigel™plugs formed in BALB/c mice. Interestingly, Lumican significantly reduced expression of matrix metallopro-teinases, particularly MMP-14 that is known to activate other MMPs in close vicinity of endothelial cellmembranes.Conclusions: Our results provide strong evidence that Lumican affects angiogenesis both by interfering withα2β1 receptor activity and downregulating proteolytic activity associated with surface membranes ofendothelial cells.© 2011 Elsevier Ltd. All rights reserved.
Francoisxavier Maquart - One of the best experts on this subject based on the ideXlab platform.
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Lumican as a multivalent effector in wound healing
Advanced Drug Delivery Reviews, 2018Co-Authors: Konstantina Karamanou, Stephane Brezillon, Francoisxavier Maquart, Gwenn PerrotAbstract:Abstract Wound healing, a complex physiological process, is responsible for tissue repair after exposure to destructive stimuli, without resulting in complete functional regeneration. Injuries can be stromal or epithelial, and most cases of wound repair have been studied in the skin and cornea. Lumican, a small leucine-rich proteoglycan, is expressed in the extracellular matrices of several tissues, such as the cornea, cartilage, and skin. This molecule has been shown to regulate collagen fibrillogenesis, keratinocyte phenotypes, and corneal transparency modulation. Lumican is also involved in the extravasation of inflammatory cells and angiogenesis, which are both critical in stromal wound healing. Lumican is the only member of the small leucine-rich proteoglycan family expressed by the epithelia during wound healing. This review summarizes the importance of Lumican in wound healing and potential methods of Lumican drug delivery to target wound repair are discussed. The involvement of Lumican in corneal wound healing is described based on in vitro and in vivo models, with critical emphasis on its underlying mechanisms of action. Similarly, the expression and role of Lumican in the healing of other tissues are presented, with emphasis on skin wound healing. Overall, Lumican promotes normal wound repair and broadens new therapeutic perspectives for impaired wound healing.
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Lumican a new inhibitor of matrix metalloproteinase 14 activity
FEBS Letters, 2014Co-Authors: Katarzyna Pietraszek, Stephane Brezillon, Corinne Perreau, Francoisxavier Maquart, Aurore Chatroncolliet, Anna Jakubiakaugustyn, Hubert Krotkiewski, Yanusz WegrowskiAbstract:Abstract We previously showed that Lumican regulates MMP-14 expression. The aim of this study was to compare the effect of Lumican and decorin on MMP-14 activity. In contrast to decorin, the glycosylated form of Lumican was able to significantly decrease MMP-14 activity in B16F1 melanoma cells. Our results suggest that a direct interaction occurs between Lumican and MMP-14. Lumican behaves as a competitive inhibitor which leads to a complete blocking of the activity of MMP-14. It binds to the catalytic domain of MMP-14 with moderate affinity ( K D ∼ 275 nM). Lumican may protect collagen against MMP-14 proteolysis, thus influencing cell–matrix interaction in tumor progression.
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Lumican: A new inhibitor of matrix metalloproteinase‐14 activity
FEBS Letters, 2014Co-Authors: Katarzyna Pietraszek, Stephane Brezillon, Corinne Perreau, Francoisxavier Maquart, Hubert Krotkiewski, Aurore Chatron-colliet, Anna Jakubiak-augustyn, Yanusz WegrowskiAbstract:Abstract We previously showed that Lumican regulates MMP-14 expression. The aim of this study was to compare the effect of Lumican and decorin on MMP-14 activity. In contrast to decorin, the glycosylated form of Lumican was able to significantly decrease MMP-14 activity in B16F1 melanoma cells. Our results suggest that a direct interaction occurs between Lumican and MMP-14. Lumican behaves as a competitive inhibitor which leads to a complete blocking of the activity of MMP-14. It binds to the catalytic domain of MMP-14 with moderate affinity ( K D ∼ 275 nM). Lumican may protect collagen against MMP-14 proteolysis, thus influencing cell–matrix interaction in tumor progression.
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Lumican effects in the control of tumour progression and their links with metalloproteinases and integrins
FEBS Journal, 2013Co-Authors: Stephane Brezillon, Francoisxavier Maquart, Katarzyna Pietraszek, Yanusz WegrowskiAbstract:Lumican is a member of the small leucine-rich proteoglycan family. It is present in numerous extracellular matrices of different tissues, such as muscle, cartilage, and cornea. In skin, Lumican is present as a glycoprotein. It plays a critical role in collagen fibrillogenesis, as shown by knocking out of its gene in mice. A direct link between Lumican expression and melanoma progression and metastasis has been demonstrated. Lumican was shown to impede tumour cell migration and invasion by directly interacting with the α2β1 integrin. In addition, an active sequence of the Lumican core protein, called lumcorin, was identified as being responsible for inhibition of melanoma cell migration. Lumican was also shown to exert angiostatic properties by downregulating the proteolytic activity associated with endothelial cell membranes, particularly matrix metalloproteinase (MMP)-14 and MMP-9. Globally, Lumican appears to be a potent agent for inhibiting tumour progression rather than tumorigenesis. However, progressive changes in proteoglycans occur in the tumour environment. The complexity and diversity of proteoglycan structure might be responsible for a variety of functions that regulate cell behaviour. Through their core protein and their glycosaminoglycan chains, proteoglycans can interact with growth factors and chemokines. These interactions affect cell signalling, motility, adhesion, growth, and apoptosis. This review summarizes recent data concerning Lumican control of tumour progression in different cancers, with a particular focus on its interactions with MMPs and integrins. Its potential therapeutic implications are discussed.
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overexpression of Lumican affects the migration of human colon cancer cells through up regulation of gelsolin and filamentous actin reorganization
Experimental Cell Research, 2012Co-Authors: Agata Radwanska, Francoisxavier Maquart, Yanusz Wegrowski, Monika Litwin, Dorota Nowak, Dagmara Baczynska, Maria MalickablaszkiewiczAbstract:Abstract Cell migration is a multistep process initiated by extracellular matrix components that leads to cytoskeletal changes and formation of different protrusive structures at the cell periphery. Lumican, a small extracellular matrix leucine-rich proteoglycan, has been shown to inhibit human melanoma cell migration by binding to α2β1 integrin and affecting actin cytoskeleton organization. The aim of this study was to determine the effect of Lumican overexpression on the migration ability of human colon adenocarcinoma LS180 cells. The cells stably transfected with plasmid containing Lumican cDNA were characterized by the increased chemotactic migration measured on Transwell filters. Lumican-overexpressing cells presented the elevated filamentous to monomeric actin ratio and gelsolin up-regulation. This was accompanied by a distinct cytoskeletal actin rearrangement and gelsolin subcellular relocation, as observed under laser scaning confocal microscope. Moreover, LS180 cells overexpressing Lumican tend to form podosome-like structures as indicated by vinculin redistribution and its colocalization with gelsolin and actin at the submembrane region of the cells. In conclusion, the elevated level of Lumican secretion to extracellular space leads to actin cytoskeletal remodeling followed by an increase in migration capacity of human colon LS180 cells. These data suggest that Lumican expression and its presence in ECM has an impact on colon cancer cells motility and may modulate invasiveness of colon cancer.
George N Tzanakakis - One of the best experts on this subject based on the ideXlab platform.
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Lumican affects tumor cell functions tumor ecm interactions angiogenesis and inflammatory response
Matrix Biology, 2014Co-Authors: Dragana Nikitovic, Antonis Papoutsidakis, Nikos K Karamanos, George N TzanakakisAbstract:Abstract The consecutive steps of tumor growth, local invasion, intravasation, extravasation and invasion of anatomically distant sites are obligatorily perpetrated through specific interactions of the tumor cells with their microenvironment. Lumican, a class II small leucine-rich proteoglycans (SLRP) has been designated key roles both in extracellular matrix (ECM) organization and as an important modulator of biological functions. This review will critically discuss Lumicans' roles in tumor development and progression. We will especially focus on correlating Lumicans' expression and distribution in tumor tissues with: (1) the organization of the tumor matrices; (2) tumor cell signaling and functions; (3) tumor cell–matrix interface; (4) tumor angiogenesis; and (5) Lumicans' potential roles in tumor-associated inflammatory response. Present knowledge of Lumicans' biology provides a fundamental platform upon which to build and deepen our understanding of Lumican function in tumorigenesis in order to be able to design credible anti-tumor approaches.
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Lumican regulates osteosarcoma cell adhesion by modulating tgfβ2 activity
The International Journal of Biochemistry & Cell Biology, 2011Co-Authors: Dragana Nikitovic, Nikos K Karamanos, Aikaterini Berdiaki, Pavlos Katonis, Georgia Chalkiadaki, John Aggelidakis, George N TzanakakisAbstract:Abstract Human osteosarcoma cell lines were recently shown to express and secrete the small leucine rich proteoglycan (SLRP) Lumican, with the ability to regulate the growth and motility of these cells. In this study, Lumican-deficient Saos 2 cells were demonstrated to have increased adhesive capability onto fibronectin (FN) (p ≤ 0.01). Upon neutralization of endogenous transforming growth factor β2 (TGF-β2) activity, no difference in the ability of Lumican siRNA-transfected and scramble siRNA-transfected Saos 2 cells to adhere onto FN was detected (p = NS). Exogenous TGF-β2 was shown to stimulate Saos 2 cell adhesion to FN (p ≤ 0.01). These results therefore, suggest that the inverse correlation existing between Lumican expression and Saos 2 cell adhesion is dependent on active TGF-β2 signaling. Furthermore, the significant increase in Smad 2 activation present in Lumican-deficient cells (p ≤ 0.01) was annulled in the presence of the anti-TGF-β2 peptide, demonstrating that Lumican is an upstream regulator of the TGF-β2/Smad 2 signaling cascade. Crucial to FN-dependent adhesion, β1 integrin expression and pFAK activation were likewise identified as downstream TGF-β2 effectors regulated by Lumican expression. In conclusion, this study demonstrates a novel out-in signaling circuit in human osteosarcoma cells: secreted to extracellular matrix Lumican is an endogenous inhibitor of TGF-β2 activity, resulting in downstream effector modulation including pSmad 2, integrin β1 and pFAK to regulate osteosarcoma adhesion.
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Lumican a small leucine rich proteoglycan
Iubmb Life, 2008Co-Authors: Dragana Nikitovic, Nikos K Karamanos, Paulos Katonis, Aristidis Tsatsakis, George N TzanakakisAbstract:Lumican belongs to the family of small leucine-rich repeat proteoglycans. Recent studies have shown that Lumican participates in the maintenance of tissue homeostasis and modulates cellular functions including cell proliferation, migration, and differentiation. The expression of Lumican has been correlated to the growth and metastasis of various malignancies; however, its exact role in tumorogenesis remains elusive. This review focuses upon the role of Lumican in cell biology, providing insights into molecular mechanisms that Lumican likely utilizes to control processes relevant to tumorogenesis. © 2008 IUBMB IUBMB Life, 60(12): 818–823, 2008
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Lumican expression is positively correlated with the differentiation and negatively with the growth of human osteosarcoma cells
FEBS Journal, 2008Co-Authors: Dragana Nikitovic, Nikos K Karamanos, Aristidis Tsatsakis, Aikaterini Berdiaki, Alexandros Zafiropoulos, Pavlos Katonis, George N TzanakakisAbstract:Osteosarcoma is the most common primary bone tumour associated with childhood and adolescence. The possible role of the small leucine-rich proteoglycan, Lumican, in the growth and metastasis of various cancer types has recently been investigated. In this study, the expression of Lumican was examined in moderately differentiated (MG-63) and well-differentiated (Saos 2) human osteosarcoma cell lines of high and low metastatic capability, respectively. Real-time PCR, western blotting with antibodies against the protein core and keratan sulfate, and specific enzymatic digestions were the methods employed. The two human osteosarcoma cell lines were found to express and secrete Lumican partly substituted with keratan sulfate glycosaminoglycans. Importantly, the non-metastatic, well-differentiated Saos 2 cells produced Lumican at rates that were up to sevenfold higher than those of highly metastatic MG-63 cells. The utilization of short interfering RNA specific for the Lumican gene resulted in efficient down-regulation of its mRNA levels in both cell lines. The growth of Saos 2 cells was inhibited by Lumican, whereas their migration and chemotactic response to fibronectin were found to be promoted. Lumican expression was negatively correlated with the basal level of Smad 2 activation in these cells, suggesting that Lumican may affect the bioavailability of Smad 2 activators. By contrast, these cellular functions of highly aggressive MG-63 cells were demonstrated not to be sensitive to a decrease in their low endogenous Lumican levels. These results suggest that Lumican expression may be positively correlated with the differentiation and negatively correlated with the progression of osteosarcoma.
James L Funderburgh - One of the best experts on this subject based on the ideXlab platform.
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Lumican is required for neutrophil extravasation following corneal injury and wound healing
Journal of Cell Science, 2010Co-Authors: Yasuhito Hayashi, James L Funderburgh, Eric C Carlson, Tai-ichiro Chikama, Mindy K Call, Eric Pearlman, George F Babcock, Yuichi OhashiAbstract:An important aspect of wound healing is the recruitment of neutrophils to the site of infection or tissue injury. Lumican, an extracellular matrix component belonging to the small leucine rich proteoglycan (SLRP) family, is one of the major keratan sulfate proteoglycans (KSPGs) within the corneal stroma. Increasing evidence indicates that Lumican can serve as a regulatory molecule for several cellular processes, including cell proliferation and migration. In the present study, we addressed the role of Lumican in the process of extravasation of polymorphonuclear leukocytes (PMNs) during the early inflammatory phase present in the healing of the corneal epithelium following debridement. We used Lum−/− mice and a novel transgenic mouse, Lum−/−,Kera-Lum, which expresses Lumican only in the corneal stroma, to assess the role of Lumican in PMN extravasation into injured corneas. Our results showed that PMNs did not readily invade injured corneas of Lum−/− mice and this defect was rescued by the expression of Lumican in the corneas of Lum−/−,Kera-Lum mice. The presence of Lumican in situ facilitates PMN infiltration into the peritoneal cavity in casein-induced inflammation. Our findings are consistent with the notion that in addition to regulating the collagen fibril architecture, Lumican acts to aid neutrophil recruitment and invasion following corneal damage and inflammation.
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keratocan a cornea specific keratan sulfate proteoglycan is regulated by Lumican
Journal of Biological Chemistry, 2005Co-Authors: Eric C Carlson, James L Funderburgh, Yasuhito Hayashi, David E Birk, Tai-ichiro Chikama, James V JesterAbstract:Abstract Lumican is an extracellular matrix glycoprotein widely distributed in mammalian connective tissues. Corneal Lumican modified with keratan sulfate constitutes one of the major proteoglycans of the stroma. Lumican-null mice exhibit altered collagen fibril organization and loss of corneal transparency. A closely related protein, keratocan, carries the remaining keratan sulfate of the cornea, but keratocan-null mice exhibit a less severe corneal phenotype. In the current study, we examined the effect of Lumican overexpression in corneas of wild type mice. These mice showed no alteration in collagen organization or transparency but had increased keratocan expression at both protein and mRNA levels. Corneas of Lumican-null mice showed decreased keratocan. This coupling of keratocan expression with Lumican also was observed after intrastromal injection of a Lumican expression minigene into the corneal stroma of Lum–/– mice. Small interfering RNA knockdown of Lumican in vitro reduced keratocan expression, whereas co-injection of a Lumican-expressing minigene with a β-galactosidase reporter driven by the keratocan promoter demonstrated an increase of keratocan transcriptional activity in response to Lumican expression in Lum–/– corneas in vivo. These observations demonstrate that Lumican has a novel regulatory role in keratocan expression at the transcriptional level. Such results help provide an explanation for the differences in severity of corneal manifestation found in Lum–/– and Kera–/– mice. The results also suggest a critical level of small proteoglycans to be essential for collagen organization but that overabundance is not detrimental to extracellular matrix morphogenesis.
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role of Lumican in the corneal epithelium during wound healing
Journal of Biological Chemistry, 2000Co-Authors: Shizuya Saika, James L Funderburgh, Atsushi Shiraishi, Satoko Saika, Richard ConverseAbstract:Abstract Lumican regulates collagenous matrix assembly as a keratan sulfate proteoglycan in the cornea and is also present in the connective tissues of other organs and embryonic corneal stroma as a glycoprotein. In normal unwounded cornea, Lumican is expressed by stromal keratocytes. Our data show that injured mouse corneal epithelium ectopically and transiently expresses Lumican during the early phase of wound healing, suggesting a potential Lumican functionality unrelated to regulation of collagen fibrillogenesis,e.g. modulation of epithelial cell adhesion or migration. An anti-Lumican antibody was found to retard corneal epithelial wound healing in cultured mouse eyes. Healing of a corneal epithelial injury in Lum −/− mice was significantly delayed compared with Lum +/− mice. These observations indicate that Lumican expressed in injured epithelium may modulate cell behavior such as adhesion or migration, thus contributing to corneal epithelial wound healing.
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characterization and expression of the mouse Lumican gene
Journal of Biological Chemistry, 1997Co-Authors: Saixia Ying, James L Funderburgh, Atsushi Shiraishi, Richard Converse, Jennifer Swiergiel, Mary R Roth, Gary W. ConradAbstract:Abstract Lumican is one of the major keratan sulfate proteoglycans (KSPG) in vertebrate corneas. We previously cloned the murine Lumican cDNA. This study determines the structure of murine Lumican gene (Lum) and its expression during mouse embryonic developments. The mouse Lumican gene was isolated from a bacterial artificial chromosome mouse genomic DNA library and characterized by polymerase chain reaction and Southern hybridization. The Lumican gene spans 6.9 kilobase pairs of mouse genome. The gene consists of three exons and two introns. Exon 1 constitutes 88 bases (b) of untranslated sequence. Exon 2 is 883 b and contains most of the coding sequence of Lumican mRNA, and exon 3 has 152 b of coding sequence and 659 b of 3′ noncoding sequence. The mouse Lumican gene has a TATCA element, a presumptive TATA box, which locates 27 b 5′-upstream from the transcription initiation site. Northern hybridization and in situ hybridization indicate that in early stages of embryonic development, day 7 post coitus the embryo expresses little or no Lumican. Thereafter, different levels of Lumican mRNA can be detected in various organ systems, such as cornea stroma, dermis, cartilage, heart, lung, and kidney. The cornea and heart are the two tissues that have the highest expression in adult. Immunoblotting studies found that KSPG core proteins became abundant in the cornea and sclera by postnatal day 10 but that sulfated KSPG could not be detected until after the eyes open. These results indicate that Lumican is widely distributed in most interstitial connective tissues. The modification of Lumican with keratan sulfates in cornea is concurrent with eye opening and may contribute to corneal transparency.
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macrophage receptors for Lumican a corneal keratan sulfate proteoglycan
Investigative Ophthalmology & Visual Science, 1997Co-Authors: James L Funderburgh, Martha L. Funderburgh, Mary R Roth, Ralene R Mitschler, Stephen K Chapes, Gary W. ConradAbstract:Purpose. Keratan sulfate proteoglycans (KSPCs) of the cornea exhibit a characteristic change in glycosylation resulting from stromal inflammation and scarring. To examine potential roles for these molecules in the pathobiology of the cornea, the authors investigated interaction of inflammatory macrophages with KSPCs in vitro. Methods. Attachment and spreading of mouse peritoneal macrophages were examined on surfaces coated with corneal proteoglycans, intact or with modified glycosylation. Solution-phase interactions were demonstrated using soluble proteoglycans labeled with 125 l-Iodine or with fluorescein. The affinity and specificity of these interactions were determined by competitive inhibition with unlabeled proteoglycans. Results. Macrophages did not adhere to intact corneal KSPGs but did attach and spread rapidly on the Lumican core protein after the removal of keratan sulfate chains. Arterial Lumican, a nonsulfated form of this proteoglycan, also stimulated macrophage attachment. Labeled arterial Lumican specifically bound to macrophages with high affinity. Flow cytometry demonstrated a high proportion of macrophages binding Lumican. Lumican binding was inhibited by divalent cation-chelators and by polyanions. Inhibition and kinetics of Lumican binding were distinct from interaction of macrophages with maleated bovine serum albumin, collagen, laminin, and fibronectin. Conclusions. The highly sulfated KSPCs of cornea do not promote macrophage adhesion; however, the low-sulfate Lumican present in pathologic corneas may act to localize macrophages in regions of inflammation, The Lumican receptor differs from macrophage scavenger receptors and from receptors for several other extracellular matrix molecules.
