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1.
Oncogene ; 29(11): 1598-610, 2010 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-20010870

RESUMO

ErbB2 amplification and overexpression in breast cancer correlates with aggressive disease and poor prognosis. To find novel ErbB2-interacting proteins, we used stable isotope labeling of amino acids in cell culture followed by peptide affinity pull-downs and identified specific binders using relative quantification by mass spectrometry. Copine-III, a member of a Ca(2+)-dependent phospholipid-binding protein family, was identified as binding to phosphorylated Tyr1248 of ErbB2. In breast cancer cells, Copine-III requires Ca(2+) for binding to the plasma membrane, where it interacts with ErbB2 upon receptor stimulation, an interaction that is dependent on receptor activity. Copine-III also binds receptor of activated C kinase 1 and colocalizes with phosphorylated focal adhesion kinase at the leading edge of migrating cells. Importantly, knockdown of Copine-III in T47D breast cancer cells causes a decrease in Src kinase activation and ErbB2-dependent wound healing. Our data suggest that Copine-III is a novel player in the regulation of ErbB2-dependent cancer cell motility. In primary breast tumors, high CPNE3 RNA levels significantly correlate with ERBB2 amplification. Moreover, in an in situ tissue microarray analysis, we detected differential protein expression of Copine-III in normal versus breast, prostate and ovarian tumors, suggesting a more general role for Copine-III in carcinogenesis.


Assuntos
Neoplasias da Mama/metabolismo , Movimento Celular , Fosfoproteínas/metabolismo , Receptor ErbB-2/metabolismo , Sítios de Ligação/genética , Western Blotting , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Modelos Biológicos , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Fosfoproteínas/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Ligação Proteica , Interferência de RNA , Receptor ErbB-2/genética , Tirosina/genética , Tirosina/metabolismo
2.
Allergy ; 64(10): 1407-1416, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19772511

RESUMO

The relationship between infant feeding patterns and the later development of food allergies has been the focus of much debate and research over the last decade. National recommendations have been made by many countries on how to feed infants to reduce the risk of food allergy but due to the lack of firm evidence the recommendations differ widely. This review has been developed as part of EuroPrevall, a European multicentre research project funded by the European Union, to document the differing feeding recommendations made across Europe, to investigate the current evidence base for any allergy prevention feeding recommendations and to identify areas where further research is needed. This review will also provide information which, when combined with the infant feeding data collected as part of EuroPrevall, will give an indication of compliance to national feeding guidelines which can be utilised to assess the effectiveness of current dissemination and implementation strategies.


Assuntos
Hipersensibilidade Alimentar/prevenção & controle , Fenômenos Fisiológicos da Nutrição do Lactente , Aleitamento Materno , Europa (Continente) , Guias como Assunto , Diretrizes para o Planejamento em Saúde , Humanos , Lactente , Fórmulas Infantis/química , Recém-Nascido
3.
Allergy ; 63(7): 797-809, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18588545

RESUMO

Peanuts are extensively cultivated around the world, providing a foodstuff that is both cheap to produce and nutritious. However, allergy to peanuts is of growing global concern, particularly given the severity of peanut-allergic reactions, which can include anaphylaxis and death. Consequently, it is important to understand the factors related to the prevalence of peanut allergy in order to inform efforts to ameliorate or pre-empt the condition. In this article we review evidence for the relevance of factors hypothesized to have some association with allergy prevalence, including both genetic and environmental factors. Although our analysis does indicate some empirical support for the importance of a number of factors, the key finding is that there are significant data gaps in the literature that undermine our ability to provide firm conclusions. We highlight these gaps, indicating questions that need to be addressed by future research.


Assuntos
Alérgenos/imunologia , Antígenos de Plantas/imunologia , Arachis/imunologia , Hipersensibilidade a Amendoim/epidemiologia , Exposição Ambiental , Europa (Continente)/epidemiologia , Manipulação de Alimentos/métodos , Predisposição Genética para Doença , Humanos , Hipersensibilidade a Amendoim/genética , Prevalência
4.
J Biol Chem ; 276(25): 22954-64, 2001 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-11304540

RESUMO

An aberrant truncated hHb1 hair keratin transcript, named hHb1-DeltaN, was previously identified in breast carcinomas. No normal tissue tested so far, including hairy skin, expressed hHb1-DeltaN, indicating that hHb1-DeltaN is related to carcinogenesis. In the present study, we investigated the mechanism by which such truncated transcript was generated in breast cancer cell lines. We found that hHb1-DeltaN transcription is initiated at an unusual cryptic promoter within the fourth intron of the hHb1 gene and is dependent on two proximal Sp1 binding sites for its baseline activity. Moreover, hHb1-DeltaN transcription is increased in response to DNA demethylation by the 5-aza-2'-deoxycytidine drug. This induction is dependent on protein neosynthesis, indicating that an additional factor is required. In addition, we showed that the hHb1-DeltaN transcript is translated in vivo as a truncated hHb1 protein that is missing the 270 amino-terminal residues. The hHb1-DeltaN protein exhibits a filament pattern throughout the cytoplasm and partially co-localizes with cytokeratin filaments, indicating its participation in the cytoskeleton network. hHb1-DeltaN might alter the adhesive properties of cancer cells.


Assuntos
Neoplasias da Mama/metabolismo , Regulação Neoplásica da Expressão Gênica , Queratinas/genética , Frações Subcelulares/metabolismo , Transcrição Gênica , Sequência de Bases , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Pegada de DNA , Metilação de DNA , Primers do DNA , Humanos , Íntrons , Queratinas/metabolismo , Dados de Sequência Molecular , Mutação , Regiões Promotoras Genéticas , Sequências Reguladoras de Ácido Nucleico , Células Tumorais Cultivadas
5.
Cancer Res ; 61(5): 2189-93, 2001 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11280785

RESUMO

Matrix metalloproteinases (MMPs) are extracellular enzymes. Some of them are known to be involved in tumor development and/or progression. Several cellular functions have been proposed for MMPs during malignant processes. Notably, they may be involved in tissue-remodeling processes through their ability to digest matrix components or to participate in tumor neoangiogenesis and, subsequently, in cancer cell proliferation. One of these MMPs, stromelysin-3 (ST3/MMP11), although devoid of enzymatic activity against the matrix components, is associated with human tumor progression and poor patient clinical outcome. Using several in vivo experimental models, it has been demonstrated that ST3 expression by the fibroblastic cells surrounding malignant epithelial cells promotes tumorigenesis in a paracrine manner. The present study was devoted to the identification of the cellular function underlying this ST3-induced tumor promotion using a syngeneic tumorigenesis model in mice. Our results show that ST3 exhibits a new and unexpected role for a MMP, because ST3-increased tumorigenesis does not result from increased neoangiogenesis or cancer cell proliferation but from decreased cancer cell death through apoptosis and necrosis. Thus, during malignancy, the cellular function of ST3 is to favor cancer cell survival in the stromal environment.


Assuntos
Apoptose/fisiologia , Neoplasias do Colo/enzimologia , Metaloendopeptidases/deficiência , Animais , Divisão Celular/fisiologia , Neoplasias do Colo/irrigação sanguínea , Neoplasias do Colo/patologia , Endogamia , Macrófagos/imunologia , Macrófagos/patologia , Metaloproteinase 11 da Matriz , Metaloendopeptidases/genética , Camundongos , Camundongos Endogâmicos BALB C , Neovascularização Patológica/enzimologia , Neutrófilos/imunologia , Neutrófilos/patologia
6.
Oncogene ; 19(12): 1605-12, 2000 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-10734321

RESUMO

Stromelysin-3 (ST3), a matrix metalloproteinase (MMP) expressed in aggressive carcinomas, has been shown to promote tumor development in different in vivo experimental models. However, the inability of its mature form to degrade extracellular matrix components casts doubt on whether ST3 functions in vivo as a protease. In this study, we evaluated whether the ST3 tumor-promoting effect could be ascribed to its proteolytic activity and whether this putative protease could be targeted with MMP inhibitors. Catalytically inactive mutant cDNA of human (h) ST3 or mouse (m) ST3 were generated and transfected into MCF7 cells. When injected into nude mice in the presence of matrigel, the mutant-bearing cells did not exhibit the enhanced tumorigenicity elicited by MCF7 cells transfected with wild-type ST3 cDNA. In a second approach, TIMP2 overproduction in MCF7 cells expressing hST3 was induced by retroviral infection. The co-expression of ST3 and TIMP2 failed to enhance the tumorigenicity of MCF7 cells. Notably, matrigel depleted of low-molecular-weight proteins and growth factors failed to promote the tumorigenicity of ST3-expressing MCF7 cells. These findings provide the first in vivo evidence that ST3 is indeed a protease that can modulate cancer progression by remodeling extracellular matrix and probably by inducing it to release the necessary microenvironmental factors. Thus, ST3 represents an interesting target for specific MMP inhibition.


Assuntos
Adenocarcinoma/genética , Neoplasias da Mama/genética , Metaloendopeptidases/genética , Metaloendopeptidases/metabolismo , Animais , Sequência de Bases , Testes de Carcinogenicidade , Domínio Catalítico , Feminino , Humanos , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/patologia , Metaloproteinase 11 da Matriz , Camundongos , Camundongos Nus , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Retroviridae/genética , Inibidor Tecidual de Metaloproteinase-2/genética , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Células Tumorais Cultivadas
7.
Biochemistry ; 38(37): 12174-9, 1999 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-10508422

RESUMO

The influence of Gln215 in stromelysin-3 (MMP-11), a residue located in the S1' subsite, was determined by producing three single mutants of this position. As compared to wild-type stromelysin-3, the kinetic parameters K(M) and k(cat) for the degradation of the fluorogenic substrate Dns-Pro-Leu-Ala-Leu-Trp-Ala-Arg-NH(2) (Dns-Leu) by these mutants indicated that the Gln/Leu substitution led to a 4-fold decrease in catalytic efficiency, whereas the mutations Gln/Tyr and Gln/Arg increased this parameter by a factor 10. The cleavage of alpha1-protease inhibitor (alpha1-PI), a natural substrate of stromelysin-3, by these mutants was also determined. Their relative activities for the degradation of alpha1-PI correspond to those observed with the synthetic substrate Dns-Leu. The catalytic efficiency of wild-type stromelysin-3 and its mutants to cleave the P1' analogue of Dns-Leu, containing the unusual amino acid Cys(OMeBn) (Dns-Cys(OMeBn)), was also determined. The values of the specificity factor, calculated as the ratio (k(cat)/K(M))Dns-Cys(OMeBn))/(k(cat)/K(M))Dns-Leu, were observed to vary from 26 for the wild-type stromelysin-3 to 120 for the Gln/Leu mutant and 25 for the Gln/Arg mutant. The Gln/Tyr mutant did not cleave the substrate when its P1' position is substituted by the unusual amino acid Cys(OMeBn). Altogether these observations established that both the catalytic activity and the specificity of stromelysin-3 are dependent on the nature of the residue in position 215. Finally, the cleavage efficiency of the Dns substrates by three representative matrixins, namely, MMP-14 (215 = Leu), MMP-1 (215 = Arg), and MMP-7 (215 = Tyr), was determined. Interestingly, the trends observed for these enzymes were similar to those established for the three mutants of stromelysin-3, pointing out the influence of position 215 toward the selectivity in this family of enzymes.


Assuntos
Glutamina/genética , Metaloendopeptidases/genética , Metaloendopeptidases/metabolismo , Mutagênese Sítio-Dirigida , Animais , Catálise , Compostos de Dansil/metabolismo , Ativação Enzimática/genética , Corantes Fluorescentes/metabolismo , Glutamina/química , Glutamina/metabolismo , Glutamina/fisiologia , Hidrólise , Cinética , Leucina/genética , Metaloproteinase 11 da Matriz , Metaloendopeptidases/química , Camundongos , Oligopeptídeos/metabolismo , Especificidade por Substrato/genética , alfa 1-Antitripsina/metabolismo
8.
Br J Cancer ; 78(12): 1640-4, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9862577

RESUMO

Human hHb1 belongs to the type II hard keratin family and is physiologically expressed in hair shafts. In the present study, using specific 3' and 5' probes for hHb1, we established that breast carcinomas ectopically express a hHb1 5'-truncated mRNA, and that this transcript is restricted to malignant epithelial cells. Furthermore, an in vitro study indicated that it could be translated. We concluded that, in breast carcinomas, expression of truncated hHb1 is related to epithelial cell transformation. Because the hHb1 gene maps to 12q11-q13, a chromosome region known to present several breakpoints in solid tumours, we propose that the hHb1 gene might represent a target for such alterations.


Assuntos
Neoplasias da Mama/metabolismo , Regulação Neoplásica da Expressão Gênica/fisiologia , Cabelo/química , Queratinas/genética , Adulto , Idoso , Sequência de Aminoácidos , Sequência de Bases , Northern Blotting , Clonagem Molecular , DNA Complementar , Feminino , Humanos , Pessoa de Meia-Idade , Dados de Sequência Molecular , Biossíntese de Proteínas , Células Tumorais Cultivadas
9.
Sante Ment Que ; 4(2): 3-10, 1979.
Artigo em Francês | MEDLINE | ID: mdl-17093681

RESUMO

In order to understand the problem of the relationship between woman and madness, it is important to take history into account. Mental illness consists in the difficulty to express one's sexual difference in a wide sense (economic, political, ideological, imaginary and symbolical), this is where history comes into consideration. Woman, relegated in the far recess of history, deprived of the possibility to express herself, is today searching for her true expression. As far as the man's confusion of ideas is concerned, because of his denial of woman, all he had left was to differentiate himself from himself and therefore creates symbolic social classes ; this thesis is not an idealistic one - it goes without saying that this symbolical evolution develops itself in interrelation with economic and material development of society. The masculine confusion of ideas (délire) is historical while the feminine one is hysterical. This view of mental illness has political and ideological consequences. The annihilation of the roots of mental illness will come about only through the elimination of social classes and the real liberation of woman. This does not mean the rejection of therapeutic work, revolutions never cured anybody, but the extension of the clinical world to politics, the breaking down of established practices and interdisciplinarity. In short term, we have to deal with individuals who feel in themselves the after effects of an aged social structure, therefore not strictly individual but collective behaviors. In the long term, only a profound social transformation can limit the number of victims of the situation. One day maybe every one will be able to express and achieve themselves in a fully realised communism. This text wanted to be a locus of information on the historical and political basis of mental illness and the interconnected role played by the feminine 'délire' (madness).

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