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1.
Anal Biochem ; 482: 16-21, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25935259

RESUMO

Basement membrane collagens or derived fragments are measured in biological fluids such as blood and urine of patients and appear to be useful for diagnosis, prognostication, or treatment monitoring as proposed for endostatin, a fragment of collagen XVIII, or tumstatin, a fragment of collagen IV. Tetrastatin, the NC1 alpha 4 collagen IV domain, was previously reported to inhibit tumor growth and angiogenesis. The aim of this study was to develop and validate a method to measure tetrastatin concentrations in human fluids. We developed a competitive enzyme-linked immunosorbent assay (ELISA). It allowed measuring tetrastatin levels in human serum, bronchial aspiration and bronchoalveolar lavage fluids, and lung tissue extracts. The tetrastatin level was significantly higher in tumor tissues than in healthy lung tissues. Tetrastatin competitive ELISA could be useful to quantify tetrastatin in tissues and biological fluids for the diagnosis or prognostication of diseases in which basement membrane metabolism may be altered, especially tumor progression.


Assuntos
Colágeno Tipo IV/análise , Colágeno Tipo IV/sangue , Ensaio de Imunoadsorção Enzimática/métodos , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/diagnóstico , Pulmão/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Líquido da Lavagem Broncoalveolar/química , Criança , Feminino , Humanos , Pulmão/química , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estrutura Terciária de Proteína , Adulto Jovem
2.
Br J Cancer ; 111(1): 139-48, 2014 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-24874477

RESUMO

BACKGROUND: The elastin-derived peptides (EDPs) exert protumoural activities by potentiating the secretion of matrix metalloproteinases (MMP) and the plasminogen-plasmin activating system. In the present paper, we studied heat-shock protein 90 (Hsp90) involvement in this mechanism. METHODS: HT-1080 fibrosarcoma cell migration and invasion were studied in artificial wound assay and modified Boyden chamber assay, respectively. Heat-shock protein 90 was studied by western blot and immunofluorescence. Matrix metalloproteinase-2 and urokinase plasminogen activator (uPA) were studied by gelatin ± plasminogen zymography and immunofluorescence. Heat-shock protein 90 partners were studied by immunoprecipitation. Messenger RNA expression was studied using real-time PCR. Small interfering RNAs were used to confirm the essential role of Hsp90. RESULTS: We showed that kappa-elastin and VGVAPG elastin hexapeptide stimulated Hsp90, pro-MMP-2 and uPA secretion within 6 h, whereas AGVPGLGVG and GRKRK peptides had no effect. No increase of mRNA level was observed. Heat-shock protein 90-specific inhibitors inhibit EDP-stimulated HT-1080 cell-invasive capacity and restrained EDP-stimulated pro-MMP-2 and uPA secretions. The inhibitory effect was reproduced by using Hsp90-blocking antibody or Hsp90 knockdown by siRNA. Heat-shock protein 90 interacted with and stabilised uPA and pro-MMP-2 in conditioned culture media of HT-1080 fibrosarcoma cells. CONCLUSIONS: Taken together, our results demonstrate that EDPs exert protumoural activities through an Hsp90-dependent mechanism involving pro-MMP-2 and uPA.


Assuntos
Movimento Celular/fisiologia , Elastina/farmacologia , Fibrossarcoma/metabolismo , Fibrossarcoma/patologia , Proteínas de Choque Térmico HSP90/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Invasividade Neoplásica , Fragmentos de Peptídeos/metabolismo , Fragmentos de Peptídeos/farmacologia , Transfecção , Ativador de Plasminogênio Tipo Uroquinase/metabolismo
3.
Anal Biochem ; 437(2): 111-7, 2013 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-23499763

RESUMO

Type XIX collagen is a minor collagen associated with basement membranes in vascular, neuronal, mesenchymal, and epithelial tissues. We demonstrated that the NC1, C-terminal, domain of collagen XIX inhibits the migration capacities of tumor cells and exerts a strong inhibition of tumor growth. Other basement membrane collagens or derived fragments were measured in biological fluids such as blood and urine of patients and appeared to be useful for diagnosis, prognosis, or treatment monitoring. The aim of this study was to develop and validate methods to measure collagen XIX and its fragments in human cell cultures, tissue extracts, and human biological fluids. For that purpose, we developed real-time PCR, Western blot, and competitive enzyme-linked immunosorbent assays. We demonstrated that the methods developed in this paper are specific for collagen XIX. We showed that it is expressed in human cell cultures, tissue extracts, and various biological fluids. These methods may be used in various human tissue extracts and biological fluids such as serum, amniotic fluid, cord blood, and many other fluids. Collagen XIX or its fragments could constitute new biomarkers for human diseases as well as for diagnosis and/or prognosis.


Assuntos
Líquidos Corporais/química , Colágeno/classificação , Colágeno/metabolismo , Células Epiteliais/metabolismo , Fibroblastos/metabolismo , Extratos de Tecidos/química , Linhagem Celular , Colágeno/química , Ensaio de Imunoadsorção Enzimática , Células Epiteliais/química , Fibroblastos/química , Regulação da Expressão Gênica/fisiologia , Humanos , Osteossarcoma/química , Osteossarcoma/metabolismo
4.
Br J Cancer ; 103(10): 1562-70, 2010 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-20959825

RESUMO

BACKGROUND: Elastin peptides possess several biological activities and in vitro data suggest they could be involved in the early phase of melanoma growth. METHODS: Using diverse in vitro and in vivo techniques (cell proliferation, invasion and migration assays, zymography, western blots, collagen degradation assay, reverse transcription PCR, melanoma allographs and immunohistochemistry), we analysed the effect of elastin-derived peptides (EDPs) on B16F1 melanoma growth and invasion, as well as on the proteolytic systems involved. RESULTS: We found that EDPs dramatically promote in vivo tumour development of B16F1 melanoma, as well as their in vitro migration and invasion. The inhibition of serine proteases and matrix metalloproteinases (MMPs) activities, by aprotinin and galardin, respectively, demonstrated that these enzymes were involved in these processes. However, we found that EDPs did not increase urokinase-type plasminogen activator, tissue-type plasminogen activator or MMP-2 expression and/or activation, neither in vitro nor in vivo. Nevertheless, we observed a strong increase of pro-MMP-9 secretion in EDPs-treated tumours and, more importantly, an increase in the expression and activation of the murine counterpart of MMP-1, named murine collagenase-A (Mcol-A). Moreover, we show that plasminogen system inhibition decreases collagen degradation by this enzyme. Finally, the use of a specific blocking antibody against Mcol-A abolished EDP-induced B16F1 invasion in vitro, showing that this MMP was directly involved in this process. CONCLUSION: Our data show that in vivo, EDPs are involved in melanoma growth and invasion and reinforced the concept of elastin fragmentation as a predictive factor.


Assuntos
Elastina/farmacologia , Metaloproteinase 1 da Matriz/metabolismo , Melanoma Experimental/genética , Melanoma Experimental/patologia , Peptídeos/farmacologia , Animais , Bovinos , Divisão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Primers do DNA , Elastina/química , Elastina/genética , Elastina/isolamento & purificação , Ativação Enzimática/efeitos dos fármacos , Feminino , Ligamentos/química , Metaloproteinase 9 da Matriz/genética , Camundongos , Camundongos Endogâmicos C57BL , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Regulação para Cima/efeitos dos fármacos
5.
Biochimie ; 87(3-4): 353-60, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15781322

RESUMO

The term "matrikines" was coined for designating peptides liberated by partial proteolysis of extracellular matrix macromolecules, which are able to regulate cell activities. Among these peptides, some of them may modulate proliferation, migration, protease production, or apoptosis. In this review, we summarize the activity of matrikines derived from elastin and interstitial or basement membrane collagens on the regulation of matrix metalloproteinases expression and/or activation, and on the plasminogen/plasmin system. Due to their activity, matrikines may play a significant role in physiological or pathological processes such as wound healing or tumor invasion.


Assuntos
Matriz Extracelular/metabolismo , Peptídeos/metabolismo , Animais , Membrana Basal/metabolismo , Colágeno/metabolismo , Elastina/metabolismo , Ativação Enzimática , Fibrinolisina/metabolismo , Regulação Enzimológica da Expressão Gênica , Humanos , Metaloproteinases da Matriz/genética , Metaloproteinases da Matriz/metabolismo , Modelos Biológicos , Invasividade Neoplásica/patologia , Peptídeo Hidrolases/metabolismo , Cicatrização/fisiologia
6.
Infect Immun ; 69(7): 4647-53, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11402009

RESUMO

Streptococcus intermedius is associated with deep-seated purulent infections. In this study, we investigated expression and functional activities of antigen I/II in S. intermedius. The S. intermedius antigen I/II appeared to be cell surface associated, with a molecular mass of approximately 160 kDa. Northern blotting indicated that the S. intermedius NCTC 11324 antigen I/II gene was transcribed as a monocistronic message. Maximum expression was seen during the early exponential phase. Insertional inactivation of the antigen I/II gene resulted in reduced hydrophobicity during early exponential phase, whereas no effect was detected during mid- and late exponential phases. Binding to human fibronectin and laminin was reduced in the isogenic mutant, whereas binding to human collagen types I and IV and to rat collagen type I was not significant for either the wild type or the mutant. Compared to the wild type, the capacity of the isogenic mutant to induce interleukin 8 (IL-8) release by THP-1 monocytic cells was significantly reduced. The results indicate that the S. intermedius antigen I/II is involved in adhesion to human receptors and in IL-8 induction.


Assuntos
Adesinas Bacterianas/fisiologia , Proteínas de Bactérias/fisiologia , Glicoproteínas de Membrana , Streptococcus , Adesinas Bacterianas/genética , Adesinas Bacterianas/imunologia , Adesinas Bacterianas/metabolismo , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/metabolismo , Linhagem Celular , Colágeno/metabolismo , Humanos , Interleucina-8/metabolismo , Microscopia de Fluorescência , Mutagênese , Ratos
7.
J Biol Chem ; 275(42): 32999-3007, 2000 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-10934203

RESUMO

We have recently identified integrin alpha(v)beta(3) and the associated CD47/integrin-associated protein (IAP) together with three other proteins as the potential tumor cell receptors for the alpha(3) chain of basement membrane type IV collagen (Shahan, T.A., Ziaie, Z., Pasco, S., Fawzi, A., Bellon, G., Monboisse, J. C., and Kefalides, N. A. (1999) Cancer Res. 59, 4584-4590). Using different cell lines expressing alpha(v)beta(3), alpha(IIb)beta(3), and/or CD47 and a liquid phase receptor capture assay, we now provide direct evidence that the synthetic and biologically active alpha3(IV)185-206 peptide, derived from the alpha3(IV) chain, interacts with the beta(3) subunit of integrin alpha(v)beta(3), independently of CD47. Increased alpha3(IV) peptide binding was observed on transforming growth factor-beta(1)-stimulated HT-144 cells shown to up-regulate alpha(v)beta(3) independently of CD47. Also, incubation of HT-144 melanoma cells in suspension induced de novo exposure of ligand-induced binding site epitopes on the beta(3) subunit similar to those observed following Arg-Gly-Asp-Ser (RGDS) stimulation. However, RGDS did not prevent HT-144 cell attachment and spreading on the alpha3(IV) peptide, suggesting that the alpha3(IV) binding domain on the beta(3) subunit is distinct from the RGD recognition site. alpha3(IV) peptide binding to HT-144 cells in suspension stimulated time-dependent tyrosine phosphorylation, while the RGDS peptide did not. Two major phosphotyrosine proteins of 120-130 and 85 kDa were immunologically identified as focal adhesion kinase and phosphatidylinositol 3-kinase (PI3-kinase). A direct involvement of PI3-kinase in alpha3(IV)-dependent beta(3) integrin signaling could be documented, since pretreatment of HT-144 cells with wortmannin, a PI3-kinase inhibitor, reverted the known inhibitory effect of alpha3(IV) on HT-144 cell proliferation as well as membrane type 1-matrix metalloproteinase gene expression. These results provide evidence that the alpha3(IV)185-206 peptide, by directly interacting with the beta(3) subunit of alpha(v)beta(3), activates a signaling cascade involving focal adhesion kinase and PI3-kinase.


Assuntos
Antígenos CD/fisiologia , Colágeno Tipo IV , Colágeno/metabolismo , Colágeno/farmacologia , Fragmentos de Peptídeos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Glicoproteínas da Membrana de Plaquetas/fisiologia , Proteínas Tirosina Quinases/metabolismo , Receptores de Vitronectina/fisiologia , Fator de Crescimento Transformador beta/farmacologia , Regulação para Cima/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Antígenos CD/química , Sítios de Ligação , Antígeno CD47 , Células CHO , Proteínas de Transporte/fisiologia , Adesão Celular , Colágeno/química , Cricetinae , Ativação Enzimática , Quinase 1 de Adesão Focal , Proteína-Tirosina Quinases de Adesão Focal , Humanos , Integrina beta3 , Melanoma , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/farmacologia , Fosforilação , Glicoproteínas da Membrana de Plaquetas/química , Receptores de Vitronectina/química , Proteínas Recombinantes/metabolismo , Transfecção , Células Tumorais Cultivadas
8.
Cancer Res ; 60(2): 467-73, 2000 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-10667602

RESUMO

The invasive properties of melanoma cells correlate with the expression of matrix metalloproteinases (MMPs) and their physiological modulators (tissue inhibitors of metalloproteinase and membrane-type MMPs) and with that of the alphaVbeta3 integrin. We investigated the effect of anterior lens capsule type IV collagen and of the alpha3(IV) collagen chain on the invasive properties of various tumor cell lines (HT-144 melanoma cells, HT-1080 fibrosarcoma cells). We demonstrated that anterior lens capsule type IV collagen or specifically the synthetic peptide alpha3(IV) 185-203 inhibited both the migration of melanoma or fibrosarcoma cells as well as the activation of membrane-bound MMP-2 by decreasing the expressions of MT1-MMP and the beta3 integrin subunit.


Assuntos
Colágeno/metabolismo , Colágeno/farmacologia , Regulação Neoplásica da Expressão Gênica , Metaloproteinases da Matriz/genética , Metaloproteinases da Matriz/metabolismo , Fragmentos de Peptídeos/farmacologia , Receptores de Vitronectina/genética , Inibidores Teciduais de Metaloproteinases/genética , Sequência de Aminoácidos , Sequência de Bases , Linhagem Celular , Membrana Celular/metabolismo , Quimiotaxia/efeitos dos fármacos , Colágeno/química , Primers do DNA , Ativação Enzimática , Fibroblastos , Fibrossarcoma , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Melanoma , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Receptores de Vitronectina/biossíntese , Pele , Inibidores Teciduais de Metaloproteinases/metabolismo , Células Tumorais Cultivadas
9.
Cancer Res ; 59(18): 4584-90, 1999 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-10493512

RESUMO

Previous studies from our laboratories demonstrated that a peptide from the noncollagenous domain of the alpha3 chain of basement membrane collagen (COL IV), comprising residues 185-203, inhibits polymorphonuclear leukocyte activation and melanoma cell proliferation independently of its ability to promote cell adhesion; these properties require the presence of the triplet -SNS- at residues 189-191 (J. C. Monboisse et al., J. Biol. Chem., 269: 25475-25482, 1994; J. Han et al., J. Biol. Chem., 272: 20395-20401, 1997). More recently, we demonstrated that native COL IV and -SNS-containing synthetic peptides (10 microg/ml) added to culture medium inhibit the proliferation of not only melanoma cells but also breast, pancreas, and stomach tumor cells up to 82% and prostate tumor cells by 15%. This inhibition was shown to be dependent on a COL IV- or peptide-induced increase in intracellular cAMP (T. A. Shahan et al., Connect. Tissue Res., 40: 221-232, 1999). Attempts to identify the putative receptor(s) on tumor cells led to the isolation of five proteins (Mr 33,000, 52,000, 72,000, 95,000, and 250,000) from melanoma and prostate cells by affinity purification with the alpha3(IV)179-208 peptide. The Mr 52,000, 95,000, and 250,000 proteins were shown to be CD47/integrin-associated protein(IAP), the integrin beta3 subunit, and the alpha(v)beta3 integrin complex, respectively. The Mr 33,000 and 72,000 proteins have not yet been identified. To confirm the specificity of ligand binding to the receptors, cell membranes from either melanoma or prostate tumor cells were pretreated with the unlabeled ligand alpha3(IV)187-191 (-YYSNS-); alternatively, the peptide was pretreated with a peptide-reactive monoclonal antibody (A5D7) before receptor isolation. These treatments inhibited the purification of CD47/IAP, the integrin beta3 subunit, and the alpha(v)beta3 integrin complex from tumor cells. Furthermore, cells treated with CD47/IAP- or the alpha(v)beta3 integrin-reactive antibodies prevented the alpha3(IV)185-203 peptide from inhibiting cell proliferation and the subsequent rise in intracellular cAMP. Pretreating cells with the alpha3(IV)187-191 (-YYSNS-) peptide also inhibited their adhesion to the alpha3(IV)185-203 peptide substrate, whereas the inactive alpha1(IV)185-203 peptide, from the same region of the alpha1 chain as the alpha3(IV)185-203 peptide, had no effect. Incubation of cells with either CD47/IAP and/or alpha(v)beta3 integrin-reactive antibodies inhibited their adhesion to the alpha3(IV)185-203 peptide, whereas antibodies to the beta1 and beta2 integrin subunits were without effect. These data suggest that ALC-COL IV, through its alpha3(IV) chain, inhibits tumor cell proliferation using the receptors CD47/IAP and the alpha(v)beta3 integrin.


Assuntos
Antígenos CD/fisiologia , Proteínas de Transporte/fisiologia , Colágeno/metabolismo , Fragmentos de Peptídeos/metabolismo , Fragmentos de Peptídeos/farmacologia , Receptores de Vitronectina/fisiologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/farmacologia , Antígenos CD/efeitos dos fármacos , Antígeno CD47 , Proteínas de Transporte/efeitos dos fármacos , Bovinos , Adesão Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Colágeno/química , AMP Cíclico/metabolismo , Humanos , Masculino , Melanoma , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Neoplasias da Próstata , Receptores de Vitronectina/efeitos dos fármacos , Trombospondinas/química , Trombospondinas/metabolismo , Células Tumorais Cultivadas
10.
Connect Tissue Res ; 40(3): 221-32, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10772543

RESUMO

Previous studies from our laboratories demonstrated that a peptide from the noncollagenous domain of the alpha3 chain of basement membrane collagen (COL IV), comprising residues 185-203, inhibits polymorphonuclear leukocyte activation and melanoma cell proliferation; this property requires the presence of the triplet -SNS- in residues 189-191 (Monboisse et al., J. Biol. Chem., 269, 25475, 1994; Han et al., J. Biol. Chem., 272, 20395, 1997). In the present study, we demonstrate that whole native COL IV and -SNS- containing synthetic peptides (10 microg/ml) added to culture medium inhibit the proliferation of not only melanoma cells, but also breast-, pancreas- and stomach-tumor cells up to 67%, and prostate tumor cells by 15%. ALC-COL IV at 5 microg/ml was shown to inhibit melanoma cell proliferation maximally at 69% and the alpha3(IV)185-203 peptide inhibited proliferation (62%) maximally at 10 microg/ml. Treatment of the alpha3(IV)185-203 peptide with either a specific mAb or a polyclonal antibody, prepared against the sequence alpha3(IV)179-208, decreased the ability of the peptide to inhibit cell proliferation by 97%, while treatment of ALC-COL IV with the same antibodies inhibited proliferation by 44%. Exposure of the above tumor cells to COL IV or the peptides resulted in an increase of intracellular cAMP that was inhibited by prior treatment of the protein with the above antibodies. To investigate the role of cAMP in the inhibition of cell proliferation, cAMP analogs and inhibitors were used. cAMP analogs mimicked the inhibitory effect of the peptide. Rp-cAMPS, a cAMP competitive inhibitor, suppressed the inhibitory effect of ALC-COL IV and of the cAMP analogs. The protein kinase-A inhibitor H-89 blocked the ability of ALC-COL IV and of the alpha3(IV)185-203 peptide to inhibit tumor cell proliferation. These data suggest that ALC-COL IV, through its alpha3(IV) chain, inhibits tumor cell proliferation utilizing a signal transduction pathway which includes cAMP and cAMP-dependent protein kinase(s).


Assuntos
Colágeno/metabolismo , AMP Cíclico/metabolismo , Sulfonamidas , Sequência de Aminoácidos , Divisão Celular/efeitos dos fármacos , Colágeno/biossíntese , Colágeno/farmacologia , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Isoquinolinas/farmacologia , Melanoma , Dados de Sequência Molecular , Biossíntese Peptídica , Células Tumorais Cultivadas
11.
J Soc Biol ; 193(4-5): 423-8, 1999.
Artigo em Francês | MEDLINE | ID: mdl-10689625

RESUMO

The activity of connective tissue cells is modulated by a number of factors present in their environment. In addition to the soluble factors such as hormones, cytokines or growth factors, cells also receive signals from the surrounding extracellular matrix (ECM) macromolecules. Moreover, they may degrade the ECM proteins and liberate peptides which may by themselves constitute new signals for the surrounding cells. Therefore, an actual regulation loop exists in connective tissue, constituted by peptides generated by ECM degradation and connective tissue cells. The term of "matrikine" has been proposed to designate such ECM-derived peptides able to regulate cell activity. In this review, we summarize some data obtained in our laboratory with two different matrikines: the tripeptide glycyl-histidyl-lysine (GHK) and the heptapeptide cysteinyl-asparaginyl-tyrosyl-tyrosyl-seryl-asparaginyl-serine (CNYYSNS). GHK is a potent activator of ECM synthesis and remodeling, whereas CNYYSNS is able to inhibit polymorphonuclear leukocytes activation and decrease the invasive capacities of cancer cells.


Assuntos
Fenômenos Fisiológicos Celulares , Tecido Conjuntivo/fisiologia , Matriz Extracelular/fisiologia , Peptídeos/fisiologia , Sequência de Aminoácidos , Animais , Humanos , Peptídeos/química
12.
J Biol Chem ; 272(33): 20395-401, 1997 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-9252346

RESUMO

Our previous studies have shown that a peptide corresponding to the residue sequence 185-203 of the NC1 domain of the alpha3 chain of basement membrane collagen (type IV) inhibits the activation of polymorphonuclear leukocytes. Peptides from the same region of the alpha1, alpha2, alpha4, and alpha5(IV) chains did not exhibit this property. Because of the intimate relationship between metastasizing neoplastic cells and vascular as well as epithelial basement membranes, we measured the cell adhesion-promoting activity of peptides from the NC1 domain of type IV collagen and their effect on proliferation of human melanoma cells. We found that peptide alpha3(IV)185-203 (CNYYSNSYSFWLASLNPER) not only promotes adhesion of human melanoma cells but also inhibits their proliferation. Adhesion increased by 50-60% over control. Melanoma cell proliferation was inhibited by 40% when cells were grown in a medium containing 5 microg/ml peptide for 5 days. Studies showed that replacement of serine in position 189 or 191 by alanine resulted in significantly reduced adhesion. Similarly, serine replacement resulted in reduced ability to inhibit proliferation. Our data suggest that a region of the NC1 domain of the alpha3(IV) chain, contained within the sequence 185-203, not only specifically promotes adhesion but also inhibits proliferation of melanoma cells. These properties appear to be dependent on the presence of the triplet sequence -SNS- (residues 189-191), which is unique to the alpha3 chain and may represent an important functional epitope.


Assuntos
Colágeno/farmacologia , Melanoma/patologia , Fragmentos de Peptídeos/farmacologia , Sequência de Aminoácidos , Anticorpos Monoclonais/imunologia , Sítios de Ligação , Adesão Celular/efeitos dos fármacos , Divisão Celular , Colágeno/química , Humanos , Dados de Sequência Molecular , Células Tumorais Cultivadas
13.
Popul Stud (Camb) ; 31(2): 267-80, 1977 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22077840

RESUMO

Summary This paper shows that the Indiana Amish, a high-fertility Anabaptist population, regulate their marital fertility according to their family finances. We linked demographic data from the Indiana Amish Directory with personal property tax records at 5, 15 and 25 years after marriage and found fertility differences by occupation and wealth. Correlations between family size and wealth at the beginning, middle and end of childbearing years were positive. Wealthier women exhibited higher marital fertility, had longer first birth intervals, were older at the birth of their last child, and had larger families than poorer women. Over the past 30 years, marital fertility has remained constant among older women; but birth rates among younger women have been rising rapidly.

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