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1.
Oncogene ; 34(17): 2189-203, 2015 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-24931164

RESUMO

Metastasis is the primary cause of cancer-related death in oncology patients. A comprehensive understanding of the molecular mechanisms that cancer cells usurp to promote metastatic dissemination is critical for the development and implementation of novel diagnostic and treatment strategies. Here we show that the membrane protein RECK (Reversion-inducing cysteine-rich protein with kazal motifs) controls breast cancer metastasis by modulating a novel, non-canonical and convergent signal transducer and activator of transcription factor 3 (STAT3)-dependent angiogenic program. Neoangiogenesis and STAT3 hyperactivation are known to be fundamentally important for metastasis, but the root molecular initiators of these phenotypes are poorly understood. Our study identifies loss of RECK as a critical and previously unknown trigger for these hallmarks of metastasis. Using multiple xenograft mouse models, we comprehensively show that RECK inhibits metastasis, concomitant with a suppression of neoangiogenesis at secondary sites, while leaving primary tumor growth unaffected. Further, with functional genomics and biochemical dissection we demonstrate that RECK controls this angiogenic rheostat through a novel complex with cell surface receptors to regulate STAT3 activation, cytokine signaling, and the induction of both vascular endothelial growth factor and urokinase plasminogen activator. In accordance with these findings, inhibition of STAT3 can rescue this phenotype both in vitro and in vivo. Taken together, our study uncovers, for the first time, that RECK is a novel regulator of multiple well-established and robust mediators of metastasis; thus, RECK is a keystone protein that may be exploited in a clinical setting to target metastatic disease from multiple angles.


Assuntos
Neoplasias da Mama/metabolismo , Proteínas Ligadas por GPI/metabolismo , Proteínas de Neoplasias/metabolismo , Neovascularização Patológica/metabolismo , Animais , Neoplasias da Mama/irrigação sanguínea , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Feminino , Proteínas Ligadas por GPI/genética , Humanos , Camundongos , Camundongos Nus , Metástase Neoplásica , Proteínas de Neoplasias/genética , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Fator de Transcrição STAT3 , Ativador de Plasminogênio Tipo Uroquinase/genética , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
2.
Bone Marrow Transplant ; 41(4): 393-8, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17994116

RESUMO

Osteopenia/osteoporosis (O/O) has been associated with allogeneic stem cell transplantation (alloSCT). We retrospectively reviewed 102 patients undergoing a first alloSCT from 2000 to 2005 at our center to evaluate the prevalence of O/O < or =6 and >6 months post-alloSCT. Fifty-six patients did not have a dual energy X-ray absorptiometry (DXA) scan following alloSCT. Approximately half (n=13/27) of those with a first DXA scan < or =6 months post-alloSCT had O/O and a similar rate (n=9/19) was seen in those with a first DXA scan >6 months. There were no significant differences in patient characteristics between the normal and O/O groups. The dual femur (DF) appeared to be more vulnerable to alloSCT-induced bone mineral density (BMD) loss than the lumbar spine (LS), regardless of screening time. O/O patients were treated with bisphosphonates and 41% had a repeat DXA scan post-treatment. No patient developed jaw osteonecrosis and significant BMD improvement was seen at the LS (mean BMD, 1.03+/-0.13 vs 1.08+/-0.12, P=0.004) but not the DF (mean BMD, 0.84+/-0.06 vs 0.85+/-0.08, P=0.29), indicating BMD loss at the DF is more resistant than the LS to antiresorptive therapy. Our results demonstrate that O/O is an early and late complication post-alloSCT and bisphosphonate treatment reverses BMD loss at the LS.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Difosfonatos/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Osteoporose/tratamento farmacológico , Osteoporose/etiologia , Condicionamento Pré-Transplante/efeitos adversos , Adolescente , Adulto , Densidade Óssea/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/epidemiologia , Prevalência , Estudos Retrospectivos , Transplante Homólogo/efeitos adversos
4.
J Gen Virol ; 74 ( Pt 11): 2499-505, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7504074

RESUMO

The envelope glycoprotein B of human cytomegalovirus (CMV) is a major target of the neutralizing antibody response against this virus, and hence has importance as a potential subunit vaccine. PCR was utilized to amplify DNA encoding the dominant antigenic determinant on this molecule, AD-1 (codons 552 to 635), and DNA sequencing was carried out in order to compare nucleotide variation in AD-1 between clinical isolates of CMV and the laboratory strain AD169. Wild-type CMV strains isolated from AIDS patients were not only more likely to possess nucleotide substitutions (19/24 compared to 5/25, P < 0.0001) than those from renal transplant recipients, but they also exhibited a greater degree of nucleotide sequence divergence (6.94 versus 0.82 substitutions/1000 bp, P < 0.0001; 96.0 to 100% versus 99.4 to 100% similarity). Increased sequence variation in the AIDS patients did not correlate with absolute peripheral blood CD4+ T cell level (r = 0.33, P > 0.1). Only two strains from AIDS patients and one strain from the renal transplant recipients possessed nucleic acid substitutions that resulted in codon changes, indicating that AD-1 is relatively well conserved amongst clinical isolates of CMV. The demonstration of strains with codon changes within neutralizing epitopes, however, highlights the importance of taking into consideration the presence of these strains within the wild-type virus population when preparing subunit vaccines.


Assuntos
Citomegalovirus/genética , DNA Viral/genética , Epitopos/genética , Variação Genética/genética , Proteínas do Envelope Viral/genética , Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Sequência de Aminoácidos , Sequência de Bases , Humanos , Transplante de Rim/imunologia , Dados de Sequência Molecular , Testes de Neutralização , Infecções Oportunistas/microbiologia , Proteínas do Envelope Viral/imunologia , Vacinas Virais/genética
5.
J Med Virol ; 41(2): 150-8, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8283177

RESUMO

Previous work by Grob et al. [Lancet i: 774, 1987] has demonstrated that allogeneic, T-cell-depleted bone marrow transplant recipients have a better prognosis for reactivated cytomegalovirus (CMV) infection if their donor is also immune. It was proposed that adoptively transferred humoral immunity was responsible for the protective effect of active infection. Immunoblot analysis using purified virions was used here to examine pre- and posttransplant antibody responses of seropositive recipients who had undergone active viral infection after transplantation. Immunoblots were assessed for the numbers of polypeptides recognised and reactivity against individual polypeptides. Immunoblots were also scanned by quantitative densitometry, and the intensity of antibody responses against total viral protein and individual polypeptides was determined. Sera from recipients with immune donors exhibited a secondary-type immune response in terms of both intensity and polypeptide specific pattern of antibody reactivity, compared with those recipients with nonimmune donors. In particular, recipients with immune donors appeared to show a greater reactivity against a protein of M(r) 55,000; this may represent the envelope glycoprotein gB, which is a major target for neutralising antibodies, and might also be utilised for preparing an effective vaccine for CMV.


Assuntos
Anticorpos Antivirais/biossíntese , Transplante de Medula Óssea/imunologia , Infecções por Citomegalovirus/imunologia , Citomegalovirus/imunologia , Linfócitos T/imunologia , Células da Medula Óssea , Linhagem Celular , Distribuição de Qui-Quadrado , Humanos , Immunoblotting , Proteínas Virais/imunologia
8.
Blood ; 79(11): 3059-66, 1992 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-1316791

RESUMO

Cytomegalovirus (CMV) remains the most common single infective cause of death following allogeneic bone marrow transplantation (BMT) from major histocompatibility complex (MHC)-identical siblings, whereas Epstein-Barr virus (EBV)-related disease is infrequent. We show here that MHC-unrestricted cytotoxic effector cells in the peripheral blood of BMT recipients are highly effective at killing EBV-infected target cells, but are inactive against CMV-infected target cells. Differential cytotoxicity is associated with disparate target structure expression. Although both EBV- and CMV-infected target cells express viral antigens, it is only those infected with EBV that express the adhesion molecule lymphocyte function-associated antigen 1 (LFA1; CD11a/18). Thus, EBV-infected target cells are able to interact with the principal LFA1 ligand, intercellular adhesion molecule 1 (ICAM1; CD54), which is expressed on posttransplant peripheral blood mononuclear (PBM) effector cells. CMV-infected target cells cannot utilize this ligand. Posttransplant cytotoxicity against EBV-infected target cells is abolished by target and effector cell blockade with monoclonal antibodies (MoAbs) to LFA1 and ICAM1, respectively, demonstrating the functional relevance of this additional ligand interaction. These results provide an illustration both of the importance and of the limitations of MHC-unrestricted cytotoxicity in vivo and may explain the frequency of CMV disease and the relative rarity of EBV-related disease following allogeneic transplantation from MHC-matched siblings. The increased immunosuppression used following MHC-mismatched/matched unrelated-donor BMT may cause this MHC-unrestricted defense mechanism to fail and may contribute to the greatly increased incidence of EBV lymphoproliferative syndrome in these patients.


Assuntos
Transplante de Medula Óssea , Citomegalovirus/imunologia , Citotoxicidade Imunológica , Antígenos HLA/imunologia , Herpesvirus Humano 4/imunologia , Antígeno-1 Associado à Função Linfocitária/imunologia , Adolescente , Adulto , Anticorpos Monoclonais , Transplante de Medula Óssea/efeitos adversos , Criança , Infecções por Citomegalovirus/etiologia , Infecções por Citomegalovirus/imunologia , Humanos , Tolerância Imunológica , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/cirurgia , Infecções Tumorais por Vírus/etiologia , Infecções Tumorais por Vírus/imunologia
9.
Science ; 235(4789): 651-8, 1987 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-17833626

RESUMO

New cements developed in recent years have strengths that are greater by an order of magnitude than those of conventional hydraulic cements. These low-temperature materials, whose strengths approach those of many traditional high-temperature ceramics, are termed chemically bonded ceramics. The different routes to generating strong cementitious materials, including warm pressing, chemical modification, high-shear mixing with polymer additions, and the making of fiber and particulate composites, are reviewed. Strength, toughness, durability, impermeability, and abrasion resistance of these new materials have been greatly improved, as have certain electrical and acoustical properties.

10.
Science ; 221(4611): 647-8, 1983 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-17787732

RESUMO

Tobermorites have cation-exchange and selectivity properties intermediate between those of clay minerals and zeolites. Aluminum-substituted tobermorites in particular show high selectivity for cesium. This new group of cation exchangers may find applications in catalysis and in nuclear and hazardous waste disposal.

11.
J Nutr ; 111(5): 878-85, 1981 May.
Artigo em Inglês | MEDLINE | ID: mdl-6164772

RESUMO

Dietary vegetable proteins may lower plasma cholesterol compared to animal proteins. We considered the possibility that lower digestibility and the trypsin inhibitor (TI) content of plant proteins could lead to alterations in bile acid metabolism and exocrine pancreatic function mediating some of this change. Mice were fed cholesterolemic diets of different protein source and TI content: casein, soy protein isolate, or casein plus TI for 4 weeks. Plasma and liver cholesterol were measured; pancreata, intestinal contents and mucosal scrapes were collected for bile acid, trypsin, chymotrypsin, amylase, and lipase assays. The soy group had lower plasma cholesterol levels. Intestinal bile acids in this group were higher, suggesting a causal relationship (increased bile acid secretion leading to increased cholesterol catabolism). Conversely, liver cholesterol in this group was raised, reflecting a possible shift in body cholesterol pools. TI addition did not affect lipid metabolism, though it did affect pancreatic function: it led to increased pancreatic weight and depressed intestinal trypsin activity, but elevated chymotrypsin and amylase levels in pancreas and intestine and increased trypsin levels in the pancreas. Therefore, soybean TI does not seem to affect cholesterol metabolism, though it greatly affects pancreatic secretion. On the other hand, soy protein has a marked effect on the bile acid and cholesterol metabolism, which may be a function of protein quality.


Assuntos
Ácidos e Sais Biliares/metabolismo , Colesterol/metabolismo , Proteínas Alimentares/farmacologia , Pâncreas/enzimologia , Proteínas de Vegetais Comestíveis/farmacologia , Amilases/metabolismo , Animais , Caseínas/farmacologia , Quimotripsina/metabolismo , Intestino Delgado/metabolismo , Lipase/metabolismo , Fígado/metabolismo , Masculino , Camundongos , Pâncreas/efeitos dos fármacos , Glycine max , Tripsina/metabolismo , Inibidores da Tripsina/farmacologia
12.
J Biomed Mater Res ; 9(4): 23-7, 1975 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1176505

RESUMO

By means of the newly developed Replamineform process, the unique pore microstructures found in the skeletal calcium carbonate of certain reef corals can be replicated or reproduced with high precision in a wide variety of materials suitable for hard tissue implant and prosthetic applications. The advantages of fabricating porous biomaterials with this method include closely controlled size of both the pore diameters and the diameters of the pore interconnections, and virtually complete interconnection of the uniformly spaced pores. These properties are of great importance in implant devices, because tissue ingrowth, the stimulation of new bone formation, the suppression of undesirable scar tissue, the inhibition of adverse body responses, and firm biological fixation of the implanted material all depend upon the nature of the pore-microstructure configuration. Replamineform preparation of Al2O3, TiO2, hydroxyapatite, silver, Co-Cr-Mo alloys, and polymers is described in detail, and the characterization procedures used to determine the physical and structural properties of their materials are discussed. A few of the routinely measured characteristics include (1) quantitative computerized SEM image analysis for determining the volume, size and shape distributions of the macro and microporosity and the grain size measurement of the solid; (2) nondestructive x-radiography of specimens to reveal any internal defects; (3) mechanical strength measurements of randomly selected specimens. Experimental results up to now clearly demonstrate the superiority of microstructures imparted to metals, ceramics, and polymers with the Replamineform process.


Assuntos
Alumínio , Materiais Biocompatíveis/síntese química , Hidroxiapatitas , Titânio , Animais , Osso e Ossos/cirurgia , Hidroxiapatitas/síntese química , Masculino , Metais/síntese química , Coelhos , Propriedades de Superfície
13.
J Biomed Mater Res ; 9(4): 29-45, 1975 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1176509

RESUMO

The Replamineform process, a new technique for the fabrication of porous hard tissue implant materials which replicates the skeletal configuration of certain marine invertebrates, was used to manufacture 1 cm long by 0.5 cm diam cylinders. The inherent advantages of porous configurations obtained through this process are controlled, uniform pore size, controlled pore-microstructure ratio, and complete interconnection of pores. The specific materials studied were chrome-cobalt-molybdenum alloy, alphaA103, hydroxyapatite prepared by hydrothermal conversion, and the basic (aragonite) CaCO3 skeleton of the coral genus Porities. The implants were placed in the canellous bone of the distal femora and proximal tibiae of adult, mongrel dogs and analyzed at 8 weeks for tissue response and ingrowth. Uniformly, new bone was found to grow into the pores of these materials and become normally mineralized. These findings were determined by microradiography, scanning electron microscopy, electron microprobe analysis, and histology. No evidences of infection, rejection, or encapsulation were seen. In the case of those CaCO3 implants left in place for 1 year, there was almost complete resorption of the cylinders, with both bony trabeculae and unmineralized collagen (presumably osteoid) found at the sites of insertion.


Assuntos
Materiais Biocompatíveis/farmacologia , Osteogênese/efeitos dos fármacos , Alumínio/farmacologia , Animais , Materiais Biocompatíveis/síntese química , Osso e Ossos/anatomia & histologia , Osso e Ossos/ultraestrutura , Carbonato de Cálcio/farmacologia , Cerâmica , Ligas de Cromo/farmacologia , Cães , Hidroxiapatitas/farmacologia
15.
Science ; 156(3782): 1593-5, 1967 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-17797642

RESUMO

Glasses synthesized under high pressure of hydrogen showed resistance to certain effects of irradiation. Paramagnetic and light-absorption effects associated with irradiated glasses were diminished by a factor as large as 20 in some glasses. Irradiation increases the concentration of hydroxyl ions, as evidenced by increased absorption in the 2.7-micron (3700 cm(-1)) infrared region for hydrogen-silica glasses.

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