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1.
Int J Cancer ; 134(11): 2572-82, 2014 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-24214898

RESUMO

Hypoxia and dysfunctional tumor vessels represent a prominent feature of pancreatic cancer, being, at least in part, responsible for chemotherapy resistance and immune suppression in these tumors. We tested whether the increase of oxygen delivery induced in vivo by myo-inositol trispyrophosphate (ITPP) can reverse hypoxia, control tumor growth and improve chemotherapy response. Tumor size, metastatic development (microcomputed tomography scan follow-up) and the survival of rats and nude or NOD.SCID mice, (bearing syngenic rat and MiaPaCa2- or patient-derived pancreatic tumors), were determined on ITPP and/or gemcitabine treatment. Partial oxygen pressure, expression of angiogenic factors and tumor histology were evaluated. Infiltration and oxidative status of immune cells, as well as chemotherapy penetration in tumors, were determined by fluorescence-activated cell sorting, fluorometry, nitric oxide release assays, Western blot and confocal microscopy. Weekly intravenous ITPP application resulted in the inhibition of metastasis development and restricted primary tumor growth, showing a superior effect on the rats' survival compared with gemcitabine. ITPP treatment restored tumor normoxia and caused a reduction in hypoxia inducible factor-1α levels, with subsequent VEGF and Lox downregulation, resulting in improved vessel structure and decreased desmoplasia. The latter effects translated into elevated immune cells influx and improved susceptibility to gemcitabine treatment. Growth of human pancreatic tumor xenografts was strongly inhibited by administration of ITPP. ITPP exploits a two-stage mechanism causing rapid, early and sustainable late stage normoxia. This is due to the angiogenic factor modulation and vascular normalization, leading to enhanced chemotherapy delivery and synergistic life prolongation, on combination with low doses of gemcitabine.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Desoxicitidina/análogos & derivados , Hipóxia/tratamento farmacológico , Fosfatos de Inositol/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Pancreáticas/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Proliferação de Células/efeitos dos fármacos , Desoxicitidina/uso terapêutico , Sinergismo Farmacológico , Imunofluorescência , Humanos , Hipóxia/metabolismo , Hipóxia/patologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/secundário , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Neovascularização Patológica , Oxigênio/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , RNA Mensageiro/genética , Ratos , Ratos Endogâmicos Lew , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas , Gencitabina
2.
Br J Cancer ; 105(2): 288-95, 2011 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-21712827

RESUMO

BACKGROUND: The transcription factor HOXC8 regulates many genes involved in tumour progression. This study was to investigate the role of HOXC8 in pancreatic ductal adenocarcinoma (PDAC) growth and metastasis. METHODS: The Hoxc8 expression was determined in 15 PDAC cell lines and human specimens by RT-polymerase chain reaction and/or immunohistochemistry. The effects of HOXC8 silencing by RNA interference were investigated by functional tests. RESULTS: The Hoxc8 mRNA expression in PDAC cell lines was negatively related to their growth in vivo. Except for Suit2-007 cells, only those with low Hoxc8 mRNA expression grew in nude rats. Successful down-regulation of HOXC8 expression caused increased proliferation, migration (P ≤ 0.05) and colony formation (P ≤ 0.05) in Suit2-007, Panc-1 and MIA PaCa-2 PDAC cells, respectively. The Hoxc8 mRNA levels in diseased human pancreas tissues were significantly increased over normal in PDAC and autoimmune chronic pancreatitis specimens (P<0.01, respectively), but negatively related to tumour stage (P=0.09). In primary and metastatic tumour samples, immunohistochemical staining for HOXC8 was stronger in surrounding than in neoplastic tissues. Furthermore, grading of primary carcinomas was negatively associated with HOXC8 staining (P=0.03). Liver metastases showed the lowest HOXC8 expression of all neoplastic lesions. CONCLUSION: These data indicate that HOXC8 expression is inversely related to PDAC progression and metastasis.


Assuntos
Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Proteínas de Homeodomínio/genética , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Adenocarcinoma/genética , Adenocarcinoma/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Estudos de Casos e Controles , Linhagem Celular Tumoral , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/fisiologia , Proteínas de Homeodomínio/antagonistas & inibidores , Proteínas de Homeodomínio/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , RNA Interferente Pequeno/farmacologia , Ratos , Ratos Nus , Ensaios Antitumorais Modelo de Xenoenxerto , Adulto Jovem
3.
Nat Cell Biol ; 3(5): 517-21, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11331882

RESUMO

Platelet-derived growth factor (PDGF) has been directly implicated in developmental and physiological processes, as well as in human cancer, fibrotic diseases and arteriosclerosis. The PDGF family currently consists of at least three gene products, PDGF-A, PDGF-B and PDGF-C, which selectively signal through two PDGF receptors (PDGFRs) to regulate diverse cellular functions. After two decades of searching, PDGF-A and B were the only ligands identified for PDGFRs. Recently, however, database mining has resulted in the discovery of a third member of the PDGF family, PDGF-C, a functional analogue of PDGF-A that requires proteolytic activation. PDGF-A and PDGF-C selectively activate PDGFR-alpha, whereas PDGF-B activates both PDGFR-alpha and PDGFR-beta. Here we identify and characterize a new member of the PDGF family, PDGF D, which also requires proteolytic activation. Recombinant, purified PDGF-D induces DNA synthesis and growth in cells expressing PDGFRs. In cells expressing individual PDGFRs, PDGF-D binds to and activates PDGFR-beta but not PDGFR-alpha. However, in cells expressing both PDGFRs, PDGF-D activates both receptors. This indicates that PDGFR-alpha activation may result from PDGFR-alpha/beta heterodimerization.


Assuntos
Linfocinas , Fator de Crescimento Derivado de Plaquetas/química , Fator de Crescimento Derivado de Plaquetas/fisiologia , Células 3T3 , Sequência de Aminoácidos , Animais , Sequência de Bases , Ligação Competitiva , Bromodesoxiuridina/metabolismo , DNA Complementar/metabolismo , Dimerização , Relação Dose-Resposta a Droga , Ativação Enzimática , Ensaio de Imunoadsorção Enzimática , Fibroblastos/metabolismo , Humanos , Camundongos , Dados de Sequência Molecular , Fosforilação , Reação em Cadeia da Polimerase , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos , Transdução de Sinais , Distribuição Tecidual , Células Tumorais Cultivadas , Tirosina/metabolismo
4.
J Exp Med ; 180(6): 2199-208, 1994 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-7964495

RESUMO

Lymphoproliferation, chronic B cell activation resulting in hypergammaglobulinemia, and profound immunodeficiency are prominent features of a retrovirus-induced syndrome designated murine acquired immunodeficiency syndrome (MAIDS). In vivo treatment of infected mice with recombinant interleukin 12 (IL-12) beginning at the time of infection or up to 9 wk after virus inoculation markedly inhibited the development of splenomegaly and lymphadenopathy, as well as B cell activation and Ig secretion. Treatment with IL-12 also had major effects in preventing induction of several immune defects including impaired production of interferon gamma (IFN-gamma) and IL-2 and depressed proliferative responses to various stimuli. The therapeutic effects of IL-12 on the immune system of mice with MAIDS were also associated with reduced expression of the retrovirus that causes this disease (BM5def), with lesser effects on expression of ecotropic MuLV. IL-12 treatment was not effective in IFN-gamma knockout mice or in infected mice treated simultaneously with IL-12 and anti-IFN-gamma. These results demonstrate that induction and progression of MAIDS are antagonized by IL-12 through high-level expression of IFN-gamma and may provide an experimental basis for developing treatments of retrovirus-induced immune disorders with similar immunopathogenic mechanisms.


Assuntos
Linfócitos B/imunologia , Interleucina-12/uso terapêutico , Síndrome de Imunodeficiência Adquirida Murina/imunologia , Animais , Anticorpos Monoclonais/farmacologia , Linfócitos B/efeitos dos fármacos , Sequência de Bases , Primers do DNA , Feminino , Citometria de Fluxo , Hipoxantina Fosforribosiltransferase/biossíntese , Interferon gama/imunologia , Interleucina-12/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Síndrome de Imunodeficiência Adquirida Murina/fisiopatologia , Síndrome de Imunodeficiência Adquirida Murina/terapia , Tamanho do Órgão/efeitos dos fármacos , Reação em Cadeia da Polimerase , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Esplenomegalia/prevenção & controle , Fatores de Tempo
5.
J Exp Med ; 190(3): 411-21, 1999 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-10430629

RESUMO

Mice with a null mutation of the gene encoding interferon consensus sequence-binding protein (ICSBP) develop a disease with marked expansion of granulocytes and macrophages that frequently progresses to a fatal blast crisis, thus resembling human chronic myelogenous leukemia (CML). One important feature of CML is decreased responsiveness of myeloid cells to apoptotic stimuli. Here we show that myeloid cells from mice deficient in ICSBP exhibit reduced spontaneous apoptosis and a significant decrease in sensitivity to apoptosis induced by DNA damage. In contrast, apoptosis in thymocytes from ICSBP-deficient mice is unaffected. We also show that overexpression of ICSBP in the human U937 monocytic cell line enhances the rate of spontaneous apoptosis and the sensitivity to apoptosis induced by etoposide, lipopolysaccharide plus ATP, or rapamycin. Programmed cell death induced by etoposide was specifically blocked by peptides inhibitory for the caspase-1 or caspase-3 subfamilies of caspases. Studies of proapoptotic genes showed that cells overexpressing ICSBP have enhanced expression of caspase-3 precursor protein. In addition, analyses of antiapoptotic genes showed that overexpression of ICSBP results in decreased expression of Bcl-X(L). These data suggest that ICSBP modulates survival of myeloid cells by regulating expression of apoptosis-related genes.


Assuntos
Apoptose/imunologia , Sequência Consenso/imunologia , Células-Tronco Hematopoéticas/patologia , Interferons/farmacologia , Proteínas Repressoras/fisiologia , Clorometilcetonas de Aminoácidos/farmacologia , Animais , Apoptose/genética , Células da Medula Óssea , Caspases/biossíntese , Caspases/genética , Caspases/metabolismo , Células Cultivadas , Inibidores de Cisteína Proteinase/farmacologia , Etoposídeo/antagonistas & inibidores , Etoposídeo/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/imunologia , Células-Tronco Hematopoéticas/enzimologia , Células-Tronco Hematopoéticas/imunologia , Células-Tronco Hematopoéticas/metabolismo , Humanos , Fatores Reguladores de Interferon , Linfonodos , Camundongos , Camundongos Knockout , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Repressoras/biossíntese , Proteínas Repressoras/genética , Baço , Células U937 , Proteína bcl-X
6.
J Exp Med ; 186(9): 1535-46, 1997 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-9348311

RESUMO

Mice with a null mutation of the gene encoding interferon consensus sequence-binding protein (ICSBP) develop a chronic myelogenous leukemia-like syndrome and mount impaired responses to certain viral and bacterial infections. To gain a mechanistic understanding of the contributions of ICSBP to humoral and cellular immunity, we characterized the responses of control and ICSBP-/- mice to infection with influenza A (flu) and Leishmania major (L. major). Mice of both genotypes survived infections with flu, but differed markedly in the isotype distribution of antiflu antibodies. In sera of normal mice, immunoglobulin (Ig)G2a antibodies were dominant over IgG1 antibodies, a pattern indicative of a T helper cell type 1 (Th1)-driven response. In sera of ICSBP-/- mice, however, IgG1 antibodies dominated over IgG2a antibodies, a pattern indicative of a Th2-driven response. The dominance of IgG1 and IgE over IgG2a was detected in the sera of uninfected mice as well. A seeming Th2 bias of ICSBP-deficient mice was also uncovered in their inability to control infection with L. major, where resistance is known to be dependent on IL-12 and IFN-gamma as components of a Th1 response. Infected ICSBP-deficient mice developed fulminant, disseminated leishmaniasis as a result of failure to mount a Th1-mediated curative response, although T cells remained capable of secreting IFN-gamma and macrophages of producing nitric oxide. Compromised Th1 differentiation in ICSBP-/- mice could not be attributed to hyporesponsiveness of CD4(+) T cells to interleukin (IL)-12; however, the ability of uninfected and infected ICSBP-deficient mice to produce IL-12 was markedly impaired. This indicates that ICSBP is a deciding factor in Th responses governing humoral and cellular immunity through its role in regulating IL-12 expression.


Assuntos
Proteínas de Transporte/imunologia , Proteínas de Transporte/fisiologia , Interleucina-12/biossíntese , Proteínas Repressoras , Fatores de Transcrição/fisiologia , Animais , Diferenciação Celular/imunologia , Sequência Consenso/imunologia , Suscetibilidade a Doenças , Vírus da Influenza A/imunologia , Fatores Reguladores de Interferon , Interferons/fisiologia , Interleucina-12/deficiência , Interleucina-12/metabolismo , Leishmania major/imunologia , Leishmaniose Cutânea/genética , Leishmaniose Cutânea/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infecções por Orthomyxoviridae/imunologia , Células Th1/citologia , Células Th2/citologia
7.
Cancer Immunol Immunother ; 59(9): 1389-400, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20514540

RESUMO

Despite spontaneous or vaccination-induced immune responses, pancreatic cancer remains one of the most deadly immunotherapy-resistant malignancies. We sought to comprehend the spectrum of pancreatic tumor-associated antigens (pTAAs) and to assess the clinical relevance of their immunogenicity. An autologous SEREX-based screening of a cDNA library constructed from a pancreatic T3N0M0/GIII specimen belonging to a long-term survivor (36 months) revealed 18 immunogenic pTAA. RT-PCR analysis displayed broad distribution of the identified antigens among normal human tissues. PNLIPRP2 and MIA demonstrated the most distinct pancreatic cancer-specific patterns. ELISA-based screening of sera for corresponding autoantibodies revealed that although significantly increased, the immunogenicity of these molecules was not a common feature in pancreatic cancer. QRT-PCR and immunohistochemistry characterized PNLIPRP2 as a robust acinar cell-specific marker whose decreased expression mirrored the disappearance of parenchyma in the diseased organ, but was not related to the presence of PNLIPRP2 autoantibodies. Analyses of MIA-known to be preferentially expressed in malignant cells-surprisingly revealed an inverse correlation between intratumoral gene expression and the emergence of autoantibodies. MIA(high) patients were autoantibody-negative and had shorter median survival when compared with autoantibody-positive MIA(low) patients (12 vs. 34 months). The observed pTAA spectrum comprised molecules associated with acinar, stromal and malignant structures, thus presenting novel targets for tumor cell-specific therapies as well as for approaches based on the bystander effects. Applying the concept of cancer immunoediting to interpret relationships between gene expression, antitumor immune responses, and clinical outcome might better discriminate between past and ongoing immune responses, consequently enabling prognostic stratification of patients and individual adjustment of immunotherapy.


Assuntos
Adenocarcinoma/diagnóstico , Adenocarcinoma/imunologia , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/imunologia , Adenocarcinoma/sangue , Adenocarcinoma/genética , Adenocarcinoma/mortalidade , Idoso , Antígenos Glicosídicos Associados a Tumores/genética , Antígenos Glicosídicos Associados a Tumores/imunologia , Antígenos Glicosídicos Associados a Tumores/metabolismo , Autoanticorpos/sangue , Clonagem Molecular , Ensaio de Imunoadsorção Enzimática , Feminino , Biblioteca Gênica , Humanos , Imunoquímica , Lipase/genética , Lipase/imunologia , Lipase/metabolismo , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Pâncreas/metabolismo , Pâncreas/patologia , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/mortalidade , Prognóstico
8.
Science ; 236(4806): 1315-8, 1987 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-3035718

RESUMO

The v-sis oncogene encodes a platelet-derived growth factor (PDGF)-related product whose transforming activity is mediated by its functional interaction with the PDGF receptor. PDGF, as well as processed forms of the v-sis gene product, is a disulfide-linked dimer with eight conserved cysteine residues in the minimum region necessary for biologic activity. Site-directed mutagenesis of the v-sis gene revealed that each conserved cysteine residue was required directly or indirectly for disulfide-linked dimer formation. However, substitution of serine for cysteine codons at any of four positions had no detrimental effect on transforming activity of the encoded v-sis protein. These results establish that interchain disulfide bonds are not essential in order for this protein to act as a functional ligand for the PDGF receptor. The remaining four substitutions of serine for cysteine each inactivated transforming function of the molecule. In each case this was associated with loss of a conformation shown to involve intramolecular disulfide bonds. These studies provide insight into the role of individual cysteine residues in determining the structure of the sis/PDGF molecule critical for biological activity.


Assuntos
Antígenos Virais de Tumores/fisiologia , Genes Virais , Proteínas Oncogênicas Virais/fisiologia , Oncogenes , Retroviridae/genética , Vírus do Sarcoma do Macaco-Barrigudo/genética , Antígenos Transformantes de Poliomavirus , Antígenos Virais de Tumores/análise , Transformação Celular Viral , Reações Cruzadas , Cisteína , Mutação , Proteínas Oncogênicas Virais/análise , Fator de Crescimento Derivado de Plaquetas/análise , Fator de Crescimento Derivado de Plaquetas/fisiologia , Conformação Proteica , Processamento de Proteína Pós-Traducional , Receptores de Superfície Celular/metabolismo , Receptores do Fator de Crescimento Derivado de Plaquetas , Serina , Transfecção
9.
Br J Cancer ; 99(5): 760-7, 2008 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-18728667

RESUMO

Efficacy of chemotherapy for pancreatic cancer may be improved by tailoring it to individual chemosensitivity profiles. Identification of nonresponders before initiation of treatment may help to avoid side effects. In this study, primary pancreatic cancer cells were isolated from 18 patients undergoing pancreaticoduodenectomy for pancreatic cancer. Eight commonly used pancreatic cancer cell lines were used as controls. Ex vivo chemosensitivity for gemcitabine, 5-fluorouracil, mitomycin-C, cisplatinum, oxaliplatinum, paclitaxel and a combination of gemcitabine with oxaliplatinum or mitomycin-C was determined using a cellular ATP-based tumour chemosensitivity assay (ATP-TCA). Quantitative real-time-polymerase chain reaction was performed to determine RNA expression levels of genes implicated in chemoresistance. Chemosensitivity towards cytotoxic agents was highly variable in primary pancreatic cancer cells and pancreatic cancer cell lines. ATP-TCA results for gemcitabine correlated to the tissue expression of human equilibrative nucleoside transporter-1 (hENT1). Time to relapse in patients with gemcitabine-sensitive tumours was significantly higher than in patients with chemoresistant pancreatic cancers (P=0.01; 71 vs 269 days). Furthermore, time to relapse in gemcitabine-treated patients was related to hENT1 expression (P=0.0067). Thus, chemosensitivity testing using ATP-TCA in pancreatic cancer is feasible and correlated with time to relapse in gemcitabine-treated patients. This suggests that ATP-TCA testing could be used as a decision-making tool in the adjuvant treatment of pancreatic cancer.


Assuntos
Antineoplásicos/uso terapêutico , Desoxicitidina/análogos & derivados , Perfilação da Expressão Gênica , Neoplasias Pancreáticas/tratamento farmacológico , Adulto , Idoso , Linhagem Celular Tumoral , Desoxicitidina/uso terapêutico , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Reação em Cadeia da Polimerase , Gencitabina
10.
Clin Exp Immunol ; 154(2): 216-23, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18778363

RESUMO

The chemokine receptor CXCR6 has been described on lymphoid cells and is thought to participate in the homing of activated T-cells to non-lymphoid tissue. We now provide evidence that the chemokine receptor CXCR6 is also expressed by activated polymorphonuclear neutrophils (PMN) in vivo: Examination of biopsies derived from patients with pancreatic carcinoma by confocal laser scan microscopy revealed a massive infiltration of PMN that expressed CXCR6, while PMN of the peripheral blood of these patients did not. To answer the question whether CXCR6 expression is a property of infiltrated and activated PMN, leucocytes were collected from patients with localized soft tissue infections in the course of the wound debridement. By cytofluorometry, the majority of these cells were identified as PMN. Up to 50% of these PMN were also positive for CXCR6. Again, PMN from the peripheral blood of these patients were nearly negative for CXCR6, as were PMN of healthy donors. In a series of in vitro experiments, up-regulation of CXCR6 on PMN of healthy donors by a variety of cytokines was tested. So far, a minor, although reproducible, effect of tumour necrosis factor (TNFalpha) was seen: brief exposure with low-dose TNFalpha induced expression of CXCR6 on the surface of PMN. Furthermore, we could show an increased migration of PMN induced by the axis CXCL16 and CXCR6. In summary, our data provide evidence that CXCR6 is not constitutively expressed on PMN, but is up-regulated under inflammatory conditions and mediates migration of CXCR6-positive PMN.


Assuntos
Infecções Bacterianas/imunologia , Proteínas de Neoplasias/metabolismo , Neutrófilos/imunologia , Neoplasias Pancreáticas/imunologia , Receptores de Quimiocinas/metabolismo , Receptores Virais/metabolismo , Doença Aguda , Quimiotaxia de Leucócito/imunologia , Humanos , Ligantes , Microscopia Confocal/métodos , Ativação de Neutrófilo/imunologia , Osteomielite/imunologia , Infecções Relacionadas à Prótese/imunologia , Receptores CXCR6 , Infecções dos Tecidos Moles/imunologia , Células Tumorais Cultivadas , Regulação para Cima/imunologia
11.
J Clin Pathol ; 59(1): 21-7, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16394277

RESUMO

BACKGROUND: Recurrent inflammation in chronic pancreatitis (CP) is not well understood. AIMS: To investigate whether decorin, an extracellular matrix (ECM) proteoglycan with macrophage modulating activity, is a pathogenic factor allowing diseased pancreatic stroma to sustain inflammation by affecting the cytokine profile of accumulating inflammatory cells. METHODS: Decorin was examined in 18 donors and 32 patients with CP by quantitative reverse transcription polymerase chain reaction (QRT-PCR), western blotting, and immunohistochemistry of pancreatic specimens. QRT-PCR was used to assess cytokine expression in donor peripheral blood mononuclear cells (PBMC), exposed or not to decorin in vitro, and to compare it with the cytokine profile of circulating and resident mononuclear cells (MNC) of patients with CP. RESULTS: In CP, desmoplasia is associated with overexpression of decorin in the growing ECM and enlarged pancreatic nerves. In culture, exposure of MNC to decorin stimulated expression of the MNC recruiting chemokine MCP-1. In biopsies, MNC infiltrates in decorin rich CP tissue showed a 300-fold upregulation of MCP-1 compared with decorin free peripheral blood, whereas no difference was found in basal MCP-1 expression in PBMC of patients versus donors. This effect was specific for MCP1-other inflammatory cytokines, such as interleukin 1beta and tumour necrosis factor alpha, were not affected. CONCLUSION: Decorin is a molecular marker of desmoplasia in CP, and excessive decorin may allow fibrotic masses to nourish and protract inflammation by deregulating the process of MNC accumulation and activation. These data provide a molecular basis for surgical resection of diseased tissue as a treatment option in CP.


Assuntos
Pancreatite Crônica/metabolismo , Proteoglicanas/fisiologia , Adolescente , Adulto , Idoso , Western Blotting , Células Cultivadas , Quimiocina CCL2/sangue , Decorina , Matriz Extracelular/metabolismo , Proteínas da Matriz Extracelular , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Técnicas Imunoenzimáticas , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade , Pâncreas/inervação , Proteoglicanas/metabolismo , Proteoglicanas/farmacologia , RNA Mensageiro/genética , Recidiva , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Regulação para Cima
12.
J Natl Cancer Inst ; 74(5): 1135-44, 1985 May.
Artigo em Inglês | MEDLINE | ID: mdl-2987593

RESUMO

The effect of all-trans-retinoic acid (RA) on cellular transformation and on tumorigenicity of retrovirally transformed cells was investigated. RA treatment of NRK and NIH/3T3 cells transformed by BALB/c murine sarcoma virus (MuSV), Kirsten murine sarcoma virus (K-MuSV), and simian sarcoma virus resulted in a significant reduction in anchorage-dependent growth of only K-MuSV-transformed NRK cells. A 62% reduction in cell number was observed at 10(-5) M RA. In contrast, anchorage-independent growth induced by each of the viruses tested was suppressed by RA. Balb/cMSV3T3 cells showed the greatest level of sensitivity with a significant reduction in anchorage-independent growth occurring at 10(-9) M RA. The level of cytoplasmic retinoic acid-binding protein (CRABP) was determined in both parent and transformed cell lines. CRABP was present at a high level in all 3T3 cell types but was absent in all NRK cell lines. For testing the antineoplastic activity of RA in vivo, Balb/cMSV3T3 cells were injected intradermally into nude mice. Subsequent treatment of the tumor sites of these animals by topical application of RA resulted in a significant reduction in both tumor incidence and tumor size, confirming the in vitro results. Analysis of the level of v-onc mRNA revealed that inhibition of retroviral transformation by RA was not due to a decrease in transcription of the v-onc genes.


Assuntos
Transformação Celular Viral/efeitos dos fármacos , Neoplasias Cutâneas/prevenção & controle , Tretinoína/farmacologia , Infecções Tumorais por Vírus/prevenção & controle , Animais , Proteínas de Transporte/análise , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Camundongos , Camundongos Nus , Oncogenes/efeitos dos fármacos , RNA Mensageiro/análise , RNA Viral/análise , Receptores do Ácido Retinoico , Vírus do Sarcoma do Macaco-Barrigudo/genética , Vírus do Sarcoma Murino/genética , Transcrição Gênica/efeitos dos fármacos , Tretinoína/uso terapêutico
13.
Cancer Biol Ther ; 4(7): 740-6, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15970685

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive malignancies, with an overall 5-year survival rate of less than 5%. Invasive tumor growth and early metastasis are two important reasons for this dismal prognosis. Osteopontin (OPN) is a secretory protein with a variety of functions, for example in cell adhesion and migration, inflammatory reaction and apoptosis. In this study the functional role of OPN in human pancreatic cancer and its potential use as a disease marker were analyzed. By real time quantitative PCR, there was a 2.2-fold and 1.6-fold increase of OPN mRNA in pancreatic cancers (n = 23) and chronic pancreatitis samples (n = 22), respectively, compared to normal pancreatic tissues (n = 20). Immunohistochemical analysis demonstrated OPN staining in 60% of the primary pancreatic tumors and in 72% of the lymph node and liver metastases. ELISA analysis of serum samples obtained from pancreatic cancer patients (n = 70), chronic pancreatitis patients (n = 12), and healthy donors (n = 20) showed a 1.6-fold increase in OPN serum levels in patients with tumors and a 1.9-fold increase in patients with chronic pancreatitis. Recombinant human OPN significantly increased the invasiveness of pancreatic cancer cells, without having any impact on cell proliferation. In addition, down regulation of OPN by specific siRNA molecules decreased pancreatic cancer cell invasion. In conclusion, OPN serum levels in pancreatic cancer and chronic pancreatitis patients are not significantly different, thereby restricting its role as a prognostic or follow-up marker. Our results do suggest, however, that blockade of OPN might be useful as a therapeutic approach to inhibit invasion and metastasis of pancreatic cancer cells.


Assuntos
Neoplasias Pancreáticas/patologia , Pancreatite Crônica/metabolismo , Sialoglicoproteínas/fisiologia , Adenocarcinoma/genética , Adenocarcinoma/patologia , Biomarcadores Tumorais/metabolismo , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Estudos de Casos e Controles , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/secundário , Metástase Linfática/patologia , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Osteopontina , Pâncreas/metabolismo , Neoplasias Pancreáticas/genética , Pancreatite Crônica/genética , Prognóstico , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/farmacologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sialoglicoproteínas/antagonistas & inibidores , Células Tumorais Cultivadas
14.
Leukemia ; 11 Suppl 3: 167-9, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9209332

RESUMO

The mechanisms responsible for development of profound immunodeficiency and extensive lymphoproliferation that characterize infection of different species with retroviruses are only partially understood. In mice, it has been shown the activities of an unusual Gag protein are necessary and sufficient to induce these abnormalities in a syndrome designated mouse AIDS (MAIDS). Current studies suggest that complex, antigen-driven interactions between T cells and B cells result in polyclonal activation of both types of lymphocytes, aberrant cytokine production and late lymphomas.


Assuntos
Produtos do Gene gag/imunologia , Vírus da Leucemia Murina/imunologia , Síndrome de Imunodeficiência Adquirida Murina/imunologia , Síndrome de Imunodeficiência Adquirida Murina/virologia , Proteínas Virais/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Citocinas/biossíntese , Citocinas/deficiência , Citocinas/genética , Vírus Defeituosos/imunologia , Vírus da Leucemia Murina/metabolismo , Ativação Linfocitária , Camundongos , Camundongos Knockout , Transcrição Gênica
16.
J Antibiot (Tokyo) ; 52(3): 235-44, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10348038

RESUMO

Nine azaphilones designated RP-1551-1, -2, -3, -4, -5, -6, -7, -M1, and -M2 were isolated from the culture broth of Penicillium sp. SPC-21609 as inhibitors of PDGF binding to its receptor. RP-1551s inhibit the binding of PDGF AA to the extracellular domain of PDGF alpha-receptor with IC50 values ranging from 0.1 to 2 microM without affecting PDGF BB binding to the extracellular domain of PDGF beta-receptor. PDGF binding was not restored after the PDGF alpha-receptor extracellular domain was washed in an attempt to remove the RP-1551-1 bound to the receptor. This result suggests that RP-1551-1 may irreversibly interact with the PDGF alpha-receptor. Since many azaphilone compounds possess high reactivity with an amino group, RP-1551-1 may prevent PDGF AA binding by reacting with amino groups on the alpha-receptor extracellular domain.


Assuntos
Antibacterianos/farmacologia , Benzopiranos/farmacologia , Penicillium/metabolismo , Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Antibacterianos/biossíntese , Antibacterianos/isolamento & purificação , Benzopiranos/isolamento & purificação , Meios de Cultura , Espaço Extracelular/metabolismo , Fermentação , Humanos , Ligação Proteica , Receptor alfa de Fator de Crescimento Derivado de Plaquetas , Receptor beta de Fator de Crescimento Derivado de Plaquetas , Proteínas Recombinantes/metabolismo , Soroalbumina Bovina/metabolismo
17.
J Antibiot (Tokyo) ; 54(5): 405-14, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11480883

RESUMO

RP-1776, a novel cyclic peptide, was isolated from the culture broth of Streptomyces sp. KY11784. RP-1776 selectively inhibited the binding of PDGF BB to the extracellular domain of the PDGF beta-receptor with an IC50 value of 11 +/- 6 microM. Detailed binding experiments suggested that RP-1776 directly interacts with PDGF BB. RP-1776 inhibited the phosphorylation of the PDGF beta-receptor induced by PDGF BB. These results suggested that RP-1776 antagonizes the signaling of PDGF BB probably through the inhibition of PDGF BB binding to the PDGF beta-receptor.


Assuntos
Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Peptídeos Cíclicos/isolamento & purificação , Peptídeos Cíclicos/farmacologia , Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Streptomyces/química , Animais , Antibacterianos/química , Becaplermina , Células CHO , Cricetinae , Depsipeptídeos , Fermentação , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Peptídeos Cíclicos/química , Fosforilação/efeitos dos fármacos , Fator de Crescimento Derivado de Plaquetas/metabolismo , Estrutura Terciária de Proteína , Proteínas Proto-Oncogênicas c-sis , Microbiologia do Solo , Streptomyces/metabolismo
18.
Braz J Med Biol Res ; 31(1): 61-7, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9686180

RESUMO

The contributions of cytokines to the development and progression of disease in a mouse model of retrovirus-induced immunodeficiency (MAIDS) are controversial. Some studies have indicated at etiologic role for type 2 cytokines, while others have emphasized the importance of type 1 cytokines. We have used mice deficient in expression of IL-4, IL-10, IL-4 and IL-10, IFN-gamma, or ICSBP-a transcriptional protein involved in IFN signaling-to examine their contributions to this disorder. Our results demonstrate that expression of type 2 cytokines is an epiphenomenon of infection and that IFN-gamma is a driving force in disease progression. In addition, exogenously administered IL-12 prevents many manifestations of disease while blocking retrovirus expression. Interruption of the IFN signaling pathways in ICSBP-/- mice blocks induction of MAIDS. Predictably, ICSBP-deficient mice exhibit impaired responses to challenge with several other viruses. This immunodeficiency is associated with impaired production of IFN-gamma and IL-12. Unexpectedly, however, the ICSBP-/- mice also develop a syndrome with many similarities to chronic myelogenous leukemia in humans. The chronic phase of this disease is followed by a fatal blast crisis characterized by clonal expansions of undifferentiated cells. ICSBP is thus an important determinant of hematopoietic growth and differentiation as well as a prominent signaling molecule for IFNs.


Assuntos
Citocinas/fisiologia , Síndrome de Imunodeficiência Adquirida Murina/imunologia , Receptores de Citocinas/fisiologia , Animais , Modelos Animais de Doenças , Camundongos , Infecções por Retroviridae
20.
J Pathol ; 215(2): 195-203, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18421760

RESUMO

In chronic pancreatitis (CP), both the progressive loss of acinar parenchyma and aggressive fibro-inflammatory reactions ultimately lead to irreversible organ destruction. Dying cells are normally removed by macrophages and elimination is associated with anti-inflammatory cytokine switch. We investigated whether defective clearance of damaged acini by macrophages such as compromised phagocytosis or altered cytokine reaction occurs in CP and thus represents a causative link between acinar loss and fibro-inflammation. In a checkerboard-like co-culture system, we assessed normal and CP macrophages for their phagocytic and cytokine responses to dying pancreatic acinar cells of normal or CP origin by FACS, confocal microscopy, QRT-PCR, and ELISA. In CP, phagocytosis of apoptotic acini by macrophages was not impaired; however, the associated cytokine responses were gradually perturbed. Most interestingly, only normal acini suppressed TGFbeta1 expression and accumulation specifically in normal macrophage cultures, while CP acini lost this ability. Both types of apoptotic acini induced pro-inflammatory cytokine bursts of varying strength in both types of macrophages; however, the most significant difference (more than 50-fold higher expression of IL-1beta, IL-6, and IL-8) was evident between CP/CP and normal/normal combinations, indicating that acinar and macrophage alterations synergistically lead to the ultimate CP-specific bias. In combination with in situ data comparing circulating inflammatory cells to pancreatic resident ones, our results indicate that cytokine expression in inflammatory cells undergoes spatiotemporal modulation, most likely through a successive interplay of acinar, stromal, and circulating factors. Thus, clearance of injured pancreatic acini by macrophages is associated with a unique cytokine reaction which may constitute a basis for progression of SAPE (sentinel acute pancreatitis event) to the irreversible fibro-inflammation in CP.


Assuntos
Macrófagos/fisiologia , Pâncreas/imunologia , Pancreatite Crônica/imunologia , Apoptose , Técnicas de Cocultura , Ensaio de Imunoadsorção Enzimática/métodos , Citometria de Fluxo , Humanos , Interleucina-1/imunologia , Interleucina-6/imunologia , Interleucina-8/imunologia , Macrófagos/imunologia , Microscopia Confocal , Pâncreas/patologia , Pancreatite Crônica/patologia , Fagocitose , Reação em Cadeia da Polimerase/métodos , Fator de Necrose Tumoral alfa/imunologia
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