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1.
Br J Cancer ; 118(2): 233-247, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29123267

RESUMO

BACKGROUND: Bactericidal/Permeability-increasing-fold-containing family B member 1 (BPIFB1, previously termed LPLUNC1) is highly expressed in the nasopharynx, significantly downregulated in nasopharyngeal carcinoma (NPC), and associated with prognosis in NPC patients. Because metastasis represents the primary cause of NPC-related death, we explored the role of BPIFB1 in NPC migration and invasion. METHODS: The role of BPIFB1 in NPC metastasis was investigated in vitro and in vivo. A co-immunoprecipitation assay coupled with mass spectrometry was used to identify BPIFB1-binding proteins. Additionally, western blotting, immunofluorescence, and immunohistochemistry allowed assessment of the molecular mechanisms associated with BPIFB1-specific metastatic inhibition via vitronectin (VTN) and vimentin (VIM) interactions. RESULTS: Our results showed that BPIFB1 expression markedly inhibited NPC cell migration, invasion, and lung-metastatic abilities. Additionally, identification of two BPIFB1-interacting proteins, VTN and VIM, showed that BPIFB1 reduced VTN expression and the formation of a VTN-integrin αV complex in NPC cells, leading to inhibition of the FAK/Src/ERK signalling pathway. Moreover, BPIFB1 attenuated NPC cell migration and invasion by inhibiting VTN- or VIM-induced epithelial-mesenchymal transition. CONCLUSIONS: This study represents the first demonstration of BPIFB1 function in NPC migration, invasion, and lung metastasis. Our findings indicate that re-expression of BPIFB1 might represent a useful strategy for preventing and treating NPC.


Assuntos
Autoantígenos/metabolismo , Carcinoma Nasofaríngeo/metabolismo , Neoplasias Nasofaríngeas/metabolismo , Proteínas/metabolismo , Vimentina/metabolismo , Vitronectina/metabolismo , Animais , Autoantígenos/biossíntese , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proteínas de Ligação a Ácido Graxo , Quinase 1 de Adesão Focal/metabolismo , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundário , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos , Camundongos Nus , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/patologia , Invasividade Neoplásica , Vimentina/antagonistas & inibidores , Vimentina/biossíntese , Vitronectina/antagonistas & inibidores , Vitronectina/biossíntese , Quinases da Família src/metabolismo
2.
Proc Natl Acad Sci U S A ; 107(8): 3558-63, 2010 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-20133714

RESUMO

Although adipose tissue is an expandable and readily attainable source of proliferating, multipotent stem cells, its potential for use in regenerative medicine has not been extensively explored. Here we report that adult human and mouse adipose-derived stem cells can be reprogrammed to induced pluripotent stem (iPS) cells with substantially higher efficiencies than those reported for human and mouse fibroblasts. Unexpectedly, both human and mouse iPS cells can be obtained in feeder-free conditions. We discovered that adipose-derived stem cells intrinsically express high levels of pluripotency factors such as basic FGF, TGFbeta, fibronectin, and vitronectin and can serve as feeders for both autologous and heterologous pluripotent cells. These results demonstrate a great potential for adipose-derived cells in regenerative therapeutics and as a model for studying the molecular mechanisms of feeder-free iPS generation and maintenance.


Assuntos
Tecido Adiposo/citologia , Células-Tronco Pluripotentes Induzidas/fisiologia , Animais , Quimera , Técnicas de Cocultura , Fatores de Crescimento de Fibroblastos , Fibroblastos/citologia , Fibroblastos/fisiologia , Fibronectinas/biossíntese , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fator de Crescimento Transformador alfa/biossíntese , Vitronectina/biossíntese
3.
Am J Physiol Renal Physiol ; 300(2): F475-87, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21048021

RESUMO

Vitronectin (VN), secreted into the bloodstream by liver hepatocytes, is known to anchor epithelial cells to basement membranes through interactions with cell surface integrin receptors. We report here that VN is also synthesized by urothelial cells of urothelium in vivo and in vitro. In situ hybridization, dideoxy sequencing, immunohistochemistry, and ELISA of urothelial cell mRNA, cDNA, tissue, and protein extracts demonstrated that the VN gene is active in vivo and in vitro. The expression of VN by urothelium is hypothesized to constitute one of several pathways that anchor basal cells to an underlying substratum and explains why urothelial cells adhere to glass and propagate under serum-free conditions. Therefore, two sources of VN in the human urinary bladder are recognized: 1) localized synthesis by urothelial cells and 2) extravasation of liver VN through fenestrated capillaries. When human plasma was fractionated by denaturing heparin affinity chromatography, VN was isolated in a biologically active form that supported rapid spreading of urothelial cells in vitro under serum-free conditions. This activity was inhibited by the matricellular protein SPARC via direct binding of VN to SPARC through a Ca(+2)-dependent mechanism. A novel form of VN, isolated from the same heparin affinity chromatography column and designated as the VN(c) chromatomer, also supported cell spreading but failed to interact with SPARC. Therefore, the steady-state balance among urothelial cells, their extracellular milieu, and matricellular proteins constitutes a principal mechanism by which urothelia are anchored to an underlying substrata in the face of constant bladder cycling.


Assuntos
Sistema Urinário/metabolismo , Urotélio/metabolismo , Vitronectina/biossíntese , Adolescente , Sequência de Aminoácidos , Sequência de Bases , Cálcio/metabolismo , Células Cultivadas , Criança , Pré-Escolar , Matriz Extracelular/metabolismo , Humanos , Lactente , Recém-Nascido , Dados de Sequência Molecular , Sistema Urinário/citologia , Vitronectina/genética
4.
Dev Dyn ; 239(3): 773-83, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20151413

RESUMO

Oocyte integrins have been described as essential for fertilization. But this concept has been challenged by deletion experiments. Recently, we have shown that sperm integrin alpha6beta1 plays a determinant role in mouse gamete interaction. In this study, we demonstrate the presence of alphavbeta3 integrin by Western blot and immunofluorescence on the sperm membrane. Oocytes and/or sperm preincubations with anti-alphav or anti-beta3 antibodies were performed before in vitro fertilization on cumulus-intact and zona-free egg assays. We observed inhibitory effects on the fusion process mostly by means of sperm function. An antibody directed against vitronectin inhibited gametes fusion, whereas the presence of exogenous vitronectin increased its efficiency. We suggest that vitronectin (on multimeric forms) can play a first nonspecific link corresponding to loosely bound spermatozoa to oocyte and that this link could be mediated by means of oocyte proteoglycans or integrins, and sperm alphavbeta3 integrin.


Assuntos
Integrina alfaVbeta3/metabolismo , Espermatozoides/metabolismo , Animais , Feminino , Fertilização , Fertilização in vitro , Ligantes , Masculino , Membranas/metabolismo , Camundongos , Microscopia de Fluorescência/métodos , Oócitos/metabolismo , Vitronectina/biossíntese
5.
PLoS One ; 15(11): e0242141, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33211735

RESUMO

Breast Cancer is the most common form of cancer in women worldwide, impacting nearly 2.1 million women each year. Identification of new biomarkers could be key for early diagnosis and detection. Vitronectin, a glycoprotein that is abundantly found in serum, extracellular matrix, and bone, binds to integrin αvß3, and promotes cell adhesion and migration. Current studies indicate that patients with amplified vitronectin levels have lower survival rates than patients without amplified vitronectin levels. In this study, we focused on the role of vitronectin in breast cancer survival and its functional role as a non-invasive biomarker for early stage and stage specific breast cancer detection. To confirm that the expression of vitronectin is amplified in breast cancer, a total of 240 serum samples (n = 240), 200 from breast cancer patients and 40 controls were analyzed using the Reverse Phase Protein Array (RPPA) technique. Of the 240 samples, 120 samples were of African American (AA) descent, while the other 120 were of White American (WA) descent. Data indicated that there were some possible racial disparities in vitronectin levels and, differences also seen in the recurrent patient samples. Next, we tried to uncover the underlying mechanism which plays a critical role in vitronectin expression. The cellular data from four different breast cancer cell lines- MCF7, MDA-MB-231, MDA-MB-468, and HCC1599 indicated that the PI3K/AKT axis is modulating the expression of vitronectin. We believe that vitronectin concentration levels are involved and connected to the metastasis of breast cancer in certain patients, specifically based on recurrence or ethnicity, which is detrimental for poor prognosis. Therefore, in this current study we showed that the serum vitronectin levels could be an early marker for the breast cancer survival and we also determine the cellular signaling factors which modulate the expression and concentration of vitronectin.


Assuntos
Neoplasias da Mama/metabolismo , Regulação Neoplásica da Expressão Gênica , Recidiva Local de Neoplasia , Vitronectina/biossíntese , Vitronectina/fisiologia , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/etnologia , Adesão Celular , Linhagem Celular Tumoral , Movimento Celular , Intervalo Livre de Doença , Eletroforese Capilar , Etnicidade , Matriz Extracelular/metabolismo , Feminino , Humanos , Células MCF-7 , Fosfatidilinositol 3-Quinases/metabolismo , Curva ROC
6.
Exp Neurol ; 312: 20-32, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30408465

RESUMO

Vitronectin (VTN) is a glycoprotein in the blood and affects hemostasis. VTN is also present in the extracellular matrix of various organs but little is known about its function in healthy adult tissues. We show, in adult mice, that VTN is uniquely expressed by approximately half of the pericytes of subventricular zone (SVZ) where neurogenesis continues throughout life. Intracerebral VTN antibody injection or VTN knockout reduced neurogenesis as well as expression of pro-neurogenic CNTF, and anti-neurogenic LIF and IL-6. Conversely, injections of VTN, or plasma from VTN+/+, but not VTN-/- mice, increased these cytokines. VTN promoted SVZ neurogenesis when LIF and IL-6 were suppressed by co-administration of a gp130 inhibitor. Unexpectedly, VTN inhibited FAK signaling and VTN-/- mice had increased FAK signaling in the SVZ. Further, an FAK inhibitor or VTN increased CNTF expression, but not in conditional astrocytic FAK knockout mice, suggesting that VTN increases CNTF through FAK inhibition in astrocytes. These results identify a novel role of pericyte-derived VTN in the brain, where it regulates SVZ neurogenesis through co-expression of CNTF, LIF and IL-6. VTN-integrin-FAK and gp130 signaling may provide novel targets to induce neurogenesis for cell replacement therapies.


Assuntos
Fator Neurotrófico Ciliar/biossíntese , Neurogênese/fisiologia , Pericitos/metabolismo , Prosencéfalo/metabolismo , Vitronectina/biossíntese , Animais , Anticorpos/administração & dosagem , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Humanos , Injeções Intraventriculares , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurogênese/efeitos dos fármacos , Pericitos/efeitos dos fármacos , Prosencéfalo/efeitos dos fármacos , Vitronectina/antagonistas & inibidores
7.
Mol Endocrinol ; 21(9): 2085-98, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17579209

RESUMO

Transcriptional activation of silent genes can require the erasure of epigenetic marks such as DNA methylation at CpGs (cytosine-guanine dinucleotide). Active demethylation events have been observed, and associated processes are repeatedly suspected to involve DNA glycosylases such as mCpG binding domain protein 4, thymine DNA glycosylase (TDG), Demeter, and repressor of silencing 1. A complete characterization of the molecular mechanisms occurring in metazoan is nonetheless awaited. Here, we report that activation of the endogenous vitronectin gene in P19 cells by the nuclear receptor chicken ovalbumin upstream promoter-transcription factor I (COUP-TFI) is observed in parallel with the recruitment of TDG and p68 RNA helicase, two components of a putative demethylation complex. Interestingly, when activated, the vitronectin gene was loaded with DNA methyltransferases 3a and 3b (Dnmt3a/b), and a strand-biased decrease in CpG methylation was detected. Dnmt3a was further found to associate with COUP-TFI and TDG in vivo, and cotransfection experiments demonstrated that Dnmt3a/b can enhance COUP-TFI-mediated activation of a methylated reporter gene. These results suggest that Dnmt3a/b could cooperate with the orphan receptor COUP-TFI to regulate transcription of the vitronectin gene.


Assuntos
Fator I de Transcrição COUP/metabolismo , DNA (Citosina-5-)-Metiltransferases/metabolismo , Regulação da Expressão Gênica/fisiologia , Animais , Células COS , Chlorocebus aethiops , DNA Metiltransferase 3A , Camundongos , Regiões Promotoras Genéticas , Ativação Transcricional , Vitronectina/biossíntese , Vitronectina/genética , DNA Metiltransferase 3B
8.
J Clin Invest ; 101(9): 1889-98, 1998 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-9576753

RESUMO

Migration of smooth muscle cells (SMCs) and collagen synthesis by SMCs are central to the pathophysiology of vascular disease. Both processes can be induced shortly after vascular injury; however, a functional relationship between them has not been established. In this study, we determined if collagen synthesis was required for SMC migration, using ethyl-3,4-dihydroxybenzoate (EDHB), an inhibitor of prolyl-4-hydroxylase, and 3,4-DL-dehydroproline (DHP), a proline analogue, which we demonstrate inhibit collagen elaboration by porcine arterial SMCs. SMCs exposed to EDHB or DHP attached normally to collagen- and vitronectin-coated substrates; however, spreading on collagen but not vitronectin was inhibited. SMC migration speed, quantified by digital time-lapse video microscopy, was significantly and reversibly reduced by EDHB and DHP. Flow cytometry revealed that expression of beta1 integrins, through which SMCs interact with collagen, was unaffected by EDHB or DHP. However, both inhibitors prevented normal clustering of beta1 integrins on the surface of SMCs, consistent with a lack of appropriate matrix ligands for integrin engagement. Moreover, there was impaired recruitment of vinculin into focal adhesion complexes of spreading SMCs and disassembly of the smooth muscle alpha-actin-containing cytoskeleton. These findings suggest that de novo collagen synthesis plays a role in SMC migration and implicates a mechanism whereby newly synthesized collagen may be necessary to maintain the transcellular traction system required for effective locomotion.


Assuntos
Artérias Carótidas/fisiologia , Movimento Celular/fisiologia , Colágeno/biossíntese , Músculo Liso Vascular/fisiologia , Actinas/metabolismo , Actinas/ultraestrutura , Animais , Artérias Carótidas/citologia , Artérias Carótidas/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Fibronectinas/biossíntese , Hidroxibenzoatos/farmacologia , Integrina beta1/metabolismo , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Pró-Colágeno-Prolina Dioxigenase/antagonistas & inibidores , Prolina/análogos & derivados , Prolina/farmacologia , Suínos , Vitronectina/biossíntese
9.
Postepy Hig Med Dosw (Online) ; 61: 485-92, 2007 Sep 28.
Artigo em Polonês | MEDLINE | ID: mdl-17909516

RESUMO

Mast cells take part in multiple pathological processes, in some of which mast cell accumulation is central to pathogenesis. They are also vital factors in many physiological reactions. Therefore it seems to be of great importance to understand the mechanisms underlying mast cell migration into and within tissues. There are many factors that regulate the migration of mast cell progenitors from the blood into tissues and the migration of mature mast cells within tissues, leading to the rapid local accumulation that occurs in diverse pathological conditions. Without any doubt, cell-surface adhesion molecules are central to the migratory process, as they facilitate the binding of cells to extracellular matrix (ECM) proteins. Immature and mature mast cells express different adhesion molecules, especially integrins, that are involved in mast cell adhesion to such ECM proteins as laminin, fibronectin, vitronectin, and collagens. The expression of adhesion molecules alters during mast cell development and maturation. What is more, mast cell adhesion molecule expression and mast cell adhesion to ECM proteins may be regulated by some cytokines.


Assuntos
Moléculas de Adesão Celular/biossíntese , Adesão Celular/fisiologia , Movimento Celular/fisiologia , Mastócitos/fisiologia , Colágeno/biossíntese , Citocinas/biossíntese , Proteínas da Matriz Extracelular/metabolismo , Fibronectinas/biossíntese , Expressão Gênica , Humanos , Integrinas/biossíntese , Laminina/biossíntese , Regulação para Cima , Vitronectina/biossíntese
10.
Mol Vis ; 12: 76-84, 2006 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-16479252

RESUMO

PURPOSE: Vitronectin is a secreted glycoprotein present in blood plasma and is present in the extracellular matrix of many tissues. It was found in the retinal cDNA library that contains genes whose expression is upregulated after optic nerve injury in a previous study. The purpose of this study was to assess the temporal and spatial changes in expression of vitronectin and integrin alphav in the retina following optic nerve injury. METHODS: Adult Balb/c mice underwent crush of the optic nerve in one eye only. RT-PCR was used to determine the temporal expression of vitronectin mRNA in the retina after injury. In addition, expression at the protein level in the retina and the optic nerve of vitronectin and its major receptor subunit, integrin alphav, was analyzed by immunohistochemistry. RESULTS: Upregulation of vitronectin mRNA in the retina was detected at one day after injury, peaking at three days, and maintained up to one week. An elevated expression of vitronectin protein was also observed in the inner retina, optic nerve head, and the optic nerve after nerve crush. In the inner retina, the increased expression of vitronectin was found in retinal ganglion cells (RGCs) and its surrounding extracellular matrix. Expression of integrin alphav was also increased in the RGC layer and in the glial cells of the nerve head and the crush site. CONCLUSIONS: As vitronectin is an extracellular protein that can support cell attachment and promote neurite extension, elevated expression of vitronectin and its receptor may facilitate axonal regeneration following injury. We propose that treatment sustaining secretion of endogenous vitronectin or direct application of exogenous vitronectin may be a method to augment regeneration of the severed optic axons.


Assuntos
Integrina alfaV/biossíntese , Traumatismos do Nervo Óptico/metabolismo , Retina/metabolismo , Vitronectina/biossíntese , Animais , Matriz Extracelular/metabolismo , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos BALB C , Compressão Nervosa , Neuroglia/metabolismo , Nervo Óptico/metabolismo , Traumatismos do Nervo Óptico/patologia , RNA Mensageiro/biossíntese , Retina/patologia , Células Ganglionares da Retina/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Distribuição Tecidual , Regulação para Cima , Vitronectina/genética
11.
Cancer Res ; 63(14): 4253-7, 2003 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-12874034

RESUMO

Angiogenesis is essential for tumor growth and metastasis. Because endothelial cells are genetically stable, they rarely acquire resistance to anticancer modalities, and could, thus, be a suitable target for radiation therapy. Heavy ion radiation therapy has attracted attention as an effective modality for cancer therapy because of its highly lethal effects, but the effects of heavy ion irradiation on in vitro cell function associated with angiogenesis have not been reported. Our study found that in vitro angiogenesis was inhibited by high linear energy transfer carbon ion irradiation even at sublethal dose (0.1 Gy). ECV304 and HUVEC human umbilical vascular endothelial cells were irradiated with 290 MeV carbon ion beams of approximately 110 keV/ micro m or 4 MV X-ray of approximately 1 keV/ micro m. Their adhesiveness and migration to vitronectin or osteopontin were inhibited, and capillary-like tube structures in three-dimensional culture were destroyed after carbon ion irradiation concomitant with the inhibition of matrix metalloproteinase-2 activity, down-regulation of alphaVbeta3 integrin, which is one of the adhesion molecules, slight up-regulation of membrane type1- matrix metalloproteinase, and significant up-regulation of tissue inhibitor of metalloproteinase-2. On the other hand, sublethal X-ray irradiation promoted migration of endothelial cells, and the capillary-like tube structure in three-dimensional culture progressed even after 16 Gy irradiation. These results provide an implication that heavy ion beam therapy could be superior to conventional photon beam therapy in preventive effects on in vitro angiogenesis even at sublethal dose, and might inhibit angiogenesis in vivo.


Assuntos
Endotélio Vascular/efeitos da radiação , Íons Pesados , Neovascularização Fisiológica/efeitos da radiação , Capilares/anatomia & histologia , Capilares/efeitos da radiação , Adesão Celular/efeitos da radiação , Movimento Celular/efeitos da radiação , Células Cultivadas , Relação Dose-Resposta à Radiação , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Humanos , Integrina alfaVbeta3/biossíntese , Integrina alfaVbeta3/metabolismo , Transferência Linear de Energia , Metaloproteinase 2 da Matriz/metabolismo , Neovascularização Fisiológica/fisiologia , Osteopontina , Sialoglicoproteínas/biossíntese , Sialoglicoproteínas/metabolismo , Vitronectina/biossíntese , Vitronectina/metabolismo
12.
Urol J ; 13(1): 2527-32, 2016 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-26945657

RESUMO

PURPOSE: To detect the expression of vitronectin (VTN) in the tissues and blood serum of prostate cancer (PCa) patients, and evaluate its clinical significance and to evaluate the significance of the combined assay of VTN and prostate specific antigens (PSA) in PCa diagnosis. MATERIALS AND METHODS: To detect the expression of VTN as a potential marker for PCa diagnosis and prognosis, immunohistochemistry was performed on the tissues of 32 patients with metastatic PCa (PCaM), 34 patients with PCa without metastasis (PCa), and 41 patients with benign prostatic hyperplasia (BPH). The sera were then subjected to Western blot analysis. All cases were subsequently examined to determine the concentrations of PSA and VTN in the sera. The collected data were collated and analyzed. RESULTS: The positive expression rates of VTN in the tissues of the BPH and PCa groups (including PCa and PCaM groups) were 75.61% and 45.45%, respectively (P = .005). VTN was more highly expressed in the sera of the BPH patients (0.83 ± 0.07) than in the sera of the PCa patients (0.65 ± 0.06) (P < .05). It was also more highly expressed in the sera of the PCa patients than in the sera of the PCaM patients (0.35 ± 0.08) (P < .05). In the diagnosis of BPH and PCa, the Youden indexes of PSA detection, VTN detection, and combined detection were 0.2620, 0.3468, and 0.5635; the kappa values were 0.338, 0.304, and 0.448, respectively, and the areas under the receiver operating characteristic curve were 0.625, 0.673, and 0.703 (P < .05), respectively. CONCLUSION: VTN levels in sera may be used as a potential marker of PCa for the diagnosis and assessment of disease progression and metastasis. The combined detection of VTN and PSA in sera can be clinically applied in PCa diagnosis. .


Assuntos
Antígeno Prostático Específico/metabolismo , Próstata/metabolismo , Neoplasias da Próstata/metabolismo , Vitronectina/biossíntese , Idoso , Biomarcadores Tumorais/metabolismo , Biópsia , Western Blotting , Humanos , Imuno-Histoquímica , Masculino , Prognóstico , Próstata/patologia , Neoplasias da Próstata/diagnóstico , Curva ROC
13.
J Cyst Fibros ; 14(5): 600-7, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26047937

RESUMO

BACKGROUND: Pseudomonas aeruginosa is a pathogen that frequently colonizes patients with cystic fibrosis (CF) or chronic obstructive pulmonary disease (COPD). Several pathogens are known to bind vitronectin to increase their virulence. Vitronectin has been shown to enhance P. aeruginosa adhesion to host epithelial cells. METHODS: We screened clinical isolates from the airways of CF patients and from the bloodstream of patients with bacteremia for binding of vitronectin. Two-dimensional SDS-PAGE and a proteomic approach were used to identify vitronectin-receptors in P. aeruginosa. RESULTS: P. aeruginosa from the airways of CF patients (n=27) bound more vitronectin than bacteremic isolates (n=15, p=0.025). Porin D (OprD) was identified as a vitronectin-binding protein. A P. aeruginosa oprD transposon insertion mutant had a decreased binding to soluble and immobilized vitronectin (p≤0.001). CONCLUSIONS: P. aeruginosa isolates obtained from CF patients significantly bound vitronectin. Porin D was defined as a novel P. aeruginosa vitronectin-receptor, and we postulate that the Porin D-dependent interaction with vitronectin may be important for colonization.


Assuntos
Fibrose Cística/microbiologia , DNA Bacteriano/genética , Regulação Bacteriana da Expressão Gênica , Porinas/genética , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/isolamento & purificação , Vitronectina/genética , Animais , Proteínas da Membrana Bacteriana Externa/biossíntese , Proteínas da Membrana Bacteriana Externa/genética , Western Blotting , Fibrose Cística/genética , Fibrose Cística/metabolismo , Modelos Animais de Doenças , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Humanos , Porinas/biossíntese , Infecções por Pseudomonas/genética , Infecções por Pseudomonas/metabolismo , Pseudomonas aeruginosa/genética , Coelhos , Sistema Respiratório/microbiologia , Vitronectina/biossíntese
14.
FEBS Lett ; 480(2-3): 169-74, 2000 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-11034322

RESUMO

The adhesive protein vitronectin (75 kDa) occurs in human blood fluid in a one-chain (Vn75) or a two-chain form (Vn65-10), and is produced by a specific cleavage (at Arg379-Ala380), by a proteinase not identified hitherto. These two forms were shown to be functionally different and therefore, this cleavage may have a regulatory significance in vivo. Here, we report the use of a tailored one-chain recombinant Vn, a specific protein kinase A phosphorylation at Ser378, and sequence analysis to show: (1) that none of the proteinases originating from blood, previously thought to be the endogenous proteinase (plasmin, thrombin, tPA, and uPA), is indeed the in vivo convertase; and (2) that furin, a serine endoproteinase residing in the secretory pathway of hepatocytes, where Vn is synthesized, specifically cleaves Vn at the endogenous cleavage site. Consequently, we propose that the Vn75 to Vn65-10 conversion takes place in the liver (not in blood) and is carried out by furin.


Assuntos
Fígado/metabolismo , Subtilisinas/metabolismo , Vitronectina/biossíntese , Alanina/metabolismo , Arginina/metabolismo , Fibrinolisina/metabolismo , Furina , Expressão Gênica , Humanos , Isoformas de Proteínas/biossíntese , Isoformas de Proteínas/genética , Isoformas de Proteínas/isolamento & purificação , Ativador de Plasminogênio Tecidual/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Vitronectina/genética , Vitronectina/isolamento & purificação
15.
Neuroscience ; 68(1): 245-53, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7477929

RESUMO

Vitronectin is a multifunctional protein involved in the regulation of the immune system and blood coagulation. Here we report that the expression of vitronectin is developmentally regulated in the embryonic retina of the chicken. Vitronectin immunoreactivity was detected in chicken retinas from embryonic day 5, encompassing the cell bodies of most neuroepithelial cells. At this developmental stage, alpha v integrin subunit expression was distributed across the retina, suggesting a ligand/receptor interaction. Expression of both vitronectin and alpha v increased during development and reached a maximum at embryonic day 9, a time when most differentiated neurons grow processes and initiate synapse formation. At this age, vitronectin immunoreactivity appeared to be located predominantly in the fiber and inner plexiform layers of the differentiated stratified retina. alpha v immunoreactivity and mRNA expression was seen associated with all layers formed by differentiated neurons, being most abundant in the ganglion cell and inner nuclear layers. Later in development, levels of vitronectin decreased and immunoreactivity appeared exclusively associated with the fiber layer. In accordance with this pattern of expression, vitronectin as a substrate sustained both proliferation and differentiation of cultured neuroepithelial cells from embryonic day 5 retinas. At later stages, vitronectin supported survival and neurite outgrowth of most differentiated neurons. Our data suggest that vitronectin is a ubiquitous component of the retinal extracellular matrix, serving as a substrate for developmental processes such as proliferation, differentiation of neuron progenitors, cell survival, and axonal and dendritic growth of differentiated neurons.


Assuntos
Neurônios/fisiologia , Retina/embriologia , Vitronectina/fisiologia , Animais , Western Blotting , Contagem de Células , Diferenciação Celular/fisiologia , Sobrevivência Celular/fisiologia , Células Cultivadas , Embrião de Galinha , Imuno-Histoquímica , Hibridização In Situ , Reação em Cadeia da Polimerase , Retina/citologia , Retina/fisiologia , Vitronectina/biossíntese
16.
Invest Ophthalmol Vis Sci ; 40(13): 3305-15, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10586957

RESUMO

PURPOSE: To determine whether vitronectin (Vn), a plasma protein and extracellular matrix molecule that is also a prominent constituent of drusen, is synthesized by cells in the adult human retina. METHODS: The distribution of Vn in the normal adult human retina was examined using antibodies to circulating plasma Vn and to the multimeric, heparin-binding form that is most prevalent in extravascular tissues. Evidence of Vn transcription by retinal cells was analyzed by in situ hybridization and also by reverse transcription of total RNA derived from dissociated human or mouse photoreceptors followed by amplification using polymerase chain reaction (RT-PCR). RESULTS: Cytoplasmic immunoreactivity for plasma Vn or multimeric Vn was detected in photoreceptors, in a subpopulation of neurons situated in the inner retina, and in vitreous hyalocytes. Extracellular labeling was limited primarily to Bruch's membrane and the retinal vasculature. At the transcriptional level, Vn mRNA was localized to both photoreceptors and ganglion cells by in situ hybridization. The in situ findings were corroborated by RT-PCR using total RNA from dissociated mouse or human photoreceptor cells. CONCLUSIONS: The results constitute the first evidence for Vn gene expression by adult neurons in the mammalian central nervous system. The identification of the photoreceptors as a cellular source of Vn suggests that these cells have the potential to make a biosynthetic contribution to the Vn that is found in drusen.


Assuntos
Expressão Gênica , RNA Mensageiro/metabolismo , Retina/metabolismo , Vitronectina/genética , Adulto , Idoso , Animais , Primers do DNA/química , Eletroforese em Gel de Poliacrilamida , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Hibridização In Situ , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Confocal , Pessoa de Meia-Idade , Células Fotorreceptoras de Vertebrados/metabolismo , Células Ganglionares da Retina/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Vitronectina/biossíntese
17.
Thromb Haemost ; 79(3): 500-8, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9580327

RESUMO

Preeclampsia is a multisystemic obstetric disease of unknown etiology that is commonly associated with fibrin deposition, occlusive lesions in placental vasculature, and intrauterine fetal growth retardation. We previously reported that type 1 plasminogen activator inhibitor (PAI-1) levels are significantly increased in plasma and placenta from pregnant women with preeclampsia compared to normal pregnant women. In the present report we localize the expression of placental PAI-1 in greater detail and compare it with that of tissue factor (TF), a procoagulant molecule, and vitronectin (Vn), a PAI-1 cofactor. We also examine the expression of two cytokines, tumor necrosis factor alpha (TNFalpha) and interleukin-1 (IL-1), in order to begin to define the underlying mechanisms responsible for the elevated levels of PAI-1 and fibrin deposits observed in placenta from preeclampsia. We demonstrate a significant increase in PAI-1, TF and TNFalpha antigen and PAI-1 and TF mRNA in placentas from preeclamptic patients. PAI-1 mRNA was increased not only in syncytiotrophoblast and infarction areas, but also in fibroblasts and in some endothelial cells of fetal vessels in placentas from preeclamptic patients. However, there was no colocalization between PAI-1, TF, Vn and TNFalpha in placental villi. The elevated TNFalpha in the placenta may induce PAI-1 and TF, and thus promote the thrombotic alterations associated with preeclampsia.


Assuntos
Placenta/metabolismo , Inibidor 1 de Ativador de Plasminogênio/biossíntese , Pré-Eclâmpsia/metabolismo , Complicações Cardiovasculares na Gravidez/metabolismo , Tromboplastina/biossíntese , Feminino , Humanos , Imuno-Histoquímica , Hibridização In Situ , Interleucina-1/biossíntese , Placenta/fisiopatologia , Pré-Eclâmpsia/fisiopatologia , Gravidez , Complicações Cardiovasculares na Gravidez/fisiopatologia , RNA Mensageiro/análise , Fator de Necrose Tumoral alfa/biossíntese , Vitronectina/biossíntese
18.
DNA Cell Biol ; 17(10): 849-58, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9809746

RESUMO

We have recently reported that the nuclei of B16 melanoma cells are intensely stained with anti-rat vitronectin (Vn) antibody, which reacts with both mouse and rat Vn. In the present study, we characterized the protein immunoreactive with the antibody using NIH3T3 cells, whose nuclei were also stained with the antibody. Western blot analysis showed that a protein with an approximate molecular weight of 75 kDa (p75), which was distinct from Vn, existed in the nuclear fraction, and, more specifically, in the nuclear matrix fraction, of NIH3T3 cells. Screening of an NIH3T3 cDNA library resulted in the isolation of a nearly full-length cDNA clone encoding p75. A database search revealed that the cDNA represents a novel gene. The deduced amino acid sequence showed that the protein is 580 amino acids long and contains two C2H2-type zinc finger motifs and glutamic acid-rich domains in the C-terminal region. When a fusion protein of green fluorescence protein and p75 was expressed in NIH3T3 cells, fluorescence was preferentially observed in the nuclei, demonstrating that the protein has a nuclear localization signal. The p75 protein, termed ZAN75, exhibited DNA-binding activity in a zinc-dependent manner. Southern blot analysis demonstrated that the ZAN75 gene exists in a single copy in the mouse genome and that a closely related gene is also present in chicken, rat, and human. Northern blot analysis showed that the ZAN75 gene is ubiquitously expressed in adult mouse tissues. In the cell cycle of NIH3T3 cells, expression was low in the G0/G1 phase, increased during the G1 phase, and persisted during the S and G2/M phases, suggesting that ZAN75 plays a role in regulating cell growth.


Assuntos
Ciclo Celular/fisiologia , Proteínas de Ligação a DNA/genética , Melanoma Experimental/metabolismo , Matriz Nuclear/metabolismo , Proteínas Nucleares/genética , Fatores de Transcrição , Dedos de Zinco , Células 3T3 , Sequência de Aminoácidos , Animais , Anticorpos , Sequência de Bases , Galinhas , Clonagem Molecular , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/química , Biblioteca Gênica , Ácido Glutâmico , Proteínas de Fluorescência Verde , Humanos , Proteínas Luminescentes/biossíntese , Camundongos , Dados de Sequência Molecular , Peso Molecular , Proteínas Nucleares/biossíntese , Proteínas Nucleares/química , Biossíntese de Proteínas , Ratos , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/química , Mapeamento por Restrição , Transcrição Gênica , Células Tumorais Cultivadas , Vitronectina/análise , Vitronectina/biossíntese
19.
Neurosci Lett ; 251(2): 109-12, 1998 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-9718986

RESUMO

Vitronectin (Vn) is a multi-functional protein that has a role in cell adhesion, and regulation of complement and blood coagulation. It has been shown to colocalize with amyloid beta peptide containing plaques and neurofibrillary tangles in Alzheimer's (AD) disease. Its normal localization in human brain tissue has not been described. In this study, Vn immunoreactivity in Purkinje cells in the human cerebellar cortex is demonstrated. This staining was present in sections from both neurologically normal and disease-affected cases. Using reverse transcription-polymerase chain reaction procedures, Vn mRNA was detected in RNA extracted from human cerebellum and cortex, from human NT2-derived neurons and from undifferentiated and differentiated SH-SY5Y neuroblastoma cells.


Assuntos
Cerebelo/metabolismo , Células de Purkinje/metabolismo , Vitronectina/biossíntese , Idoso , Química Encefálica , Cerebelo/química , Cerebelo/citologia , Humanos , Imuno-Histoquímica , Células de Purkinje/química , Vitronectina/análise
20.
Arch Pharm Res ; 25(4): 469-74, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12214858

RESUMO

The inner shell of the chestnut (Castanea crenata S. et Z., Fagaceae) has been used as an anti-wrinkle/skin firming agent in East Asia, and preliminary experiments have found that a 70% ethanol extract from this plant material can prevent cell detachment of skin fibroblasts from culture plates. In order to examine the molecular mechanisms underlying this phenomenon, its effects on the expression of adhesion molecules, such as fibronectin and vitronectin, were investigated using the mouse skin fibroblast cell line, NIH/3T3. Using fixed-cell ELISA, Western blotting and immunofluorescence cell staining, it was clearly demonstrated that the chestnut inner shell extract enhanced the expression of the cell-associated fibronectin and vitronectin. Scoparone (6,7-dimethoxycoumarin), isolated from the extract, also possessed similar properties. These findings suggest that the enhanced expression of the adhesion molecules may be one of the molecular mechanisms for how the chestnut inner shell extract preventing cell detachment and may be also responsible for its anti-wrinkle/skin firming effect.


Assuntos
Moléculas de Adesão Celular/biossíntese , Fibronectinas/biossíntese , Nozes/química , Vitronectina/biossíntese , Células 3T3 , Animais , Western Blotting , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Cumarínicos/química , Cumarínicos/isolamento & purificação , Ensaio de Imunoadsorção Enzimática , Fibroblastos/efeitos dos fármacos , Imunofluorescência , Camundongos , Extratos Vegetais/farmacologia , Pele/citologia , Pele/efeitos dos fármacos
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