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2.
Int J Hematol ; 87(1): 69-74, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18224416

RESUMO

It is quite rare to diagnose interstitial nephritis and secondary amyloidosis during the course of Castleman's disease (CD). To our knowledge, only four cases of interstitial nephritis and 44 cases of amyloidosis associated with CD have been reported to date. A 51-year-old man with a 9-year history of hypergammaglobulinemia was diagnosed with multicentric Castleman's disease of the plasma cell type. At the age of 55, it was complicated with interstitial nephritis, which was successfully treated with steroids and cyclophosphamide. At the age of 58, he was diagnosed with secondary AA amyloidosis and thrombocytopenia, which led to a fatal brain hemorrhage. The plasma cell type of this illness involves a relatively high incidence of amyloidosis, and the present patient suggests that some cases of multicentric Castleman's disease could proceed rapidly, be unresponsive to steroid therapy, and may have a fatal outcome.


Assuntos
Amiloidose/complicações , Hiperplasia do Linfonodo Gigante/complicações , Nefrite Intersticial/complicações , Hiperplasia do Linfonodo Gigante/patologia , Evolução Fatal , Humanos , Masculino , Pessoa de Meia-Idade , Nefrite Intersticial/patologia , Proteína Amiloide A Sérica
3.
Anticancer Res ; 28(5A): 2701-4, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19035298

RESUMO

BACKGROUND: Wnt/beta-catenin signaling is involved in the growth of various types of cancer cells. Wnt3A has been reported to promote the self-renewal of hematopoietic stem cells. MATERIALS AND METHODS: The effects of recombinant Wnt3A protein on the in vitro growth of four acute myeloid leukemia (AML) and four acute T-lymphoblastic leukemia (T-ALL) cell lines was examined. RESULTS: Wnt3A stimulation either had no effect on, or slightly suppressed, the short-term growth of these cell lines. In three cell lines, Wnt3A promoted clonogenic cell recovery after suspension culture, suggesting the promotion of the self-renewal capacity of leukemic stem or progenitor cells. Immunoblot analysis showed that Wnt3A stimulation reduced phosphorylated beta-catenin and increased beta-catenin in these cells, indicating that Wnt3A stimulation activated Wnt/beta-catenin signaling. CONCLUSION: Wnt3A stimulation did not promote the growth of whole cell populations, but did promote the self-renewal of leukemic stem/progenitor cells in some AML and T-ALL cell lines.


Assuntos
Leucemia Mieloide/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Proteínas Wnt/farmacologia , ADP-Ribosil Ciclase 1/biossíntese , Doença Aguda , Antígenos CD34/biossíntese , Proteínas de Ligação ao Cálcio/biossíntese , Proteínas de Ligação ao Cálcio/genética , Processos de Crescimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Expressão Gênica/efeitos dos fármacos , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/biossíntese , Peptídeos e Proteínas de Sinalização Intercelular/genética , Leucemia Mieloide/genética , Leucemia Mieloide/metabolismo , Leucemia Mieloide/patologia , Proteínas de Membrana/biossíntese , Proteínas de Membrana/genética , Células-Tronco Neoplásicas/efeitos dos fármacos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptor Notch1/biossíntese , Receptor Notch1/genética , Proteínas Recombinantes/farmacologia , Proteínas Serrate-Jagged , Proteína Wnt3 , Proteína Wnt3A
4.
Oncol Rep ; 18(1): 77-80, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17549349

RESUMO

gamma-Secretase inhibitors (GSI) suppress the growth of acute T-lymphoblastic leukemia (T-ALL) cells with NOTCH1 mutations. Recently, clinical trials of GSI for refractory T-ALL have commenced. In the present study, we examined the effects of three types of GSI; GSI-I, GSI-IX, and GSI-XII on the growth of four B-cell malignant lymphoma (B-ML) and four acute myeloid leukemia (AML) cell lines as well as four T-ALL cell lines. We found that GSI also suppressed the in vitro growth of some B-ML and AML cell lines in a dose-dependent manner. Growth suppression occurred through induction of apoptosis. Expression of the HES1 gene, one of the targets of Notch signaling, was high in T-ALL cells with NOTCH1 mutations, but was low in GSI-sensitive B-ML and AML cells. GSI treatment decreased HES1 mRNA expression in T-ALL cells, while GSI increased HES1 mRNA in two GSI-sensitive B-ML and AML cell lines. In immunoblot analysis, the band for the intracellular fragment of Notch1, an active form of Notch1, was dense in T-ALL cells but was faint in GSI-sensitive B-ML and AML cells; attenuation of the band by GSI was not evident. These findings suggest that GSI may act on Notch 2, 3 or 4 protein, or some pathways other than Notch signaling in GSI-sensitive B-ML and AML cells. Namely, growth suppression by GSI may involve cell growth-related proteins, which are gamma-secretase substrates. Taken together, we have shown that GSI may be useful for the treatment of hematological malignancies other than T-ALL. The mechanism behind the effects remains to be clarified. Our investigations lead to a novel molecular target therapy for chemotherapy-resistant leukemia and lymphomas.


Assuntos
Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Proliferação de Células/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Leucemia Mieloide Aguda/patologia , Linfoma de Células B/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Apoptose/efeitos dos fármacos , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Linfoma de Células B/metabolismo , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/metabolismo , Mutação/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Receptores Notch/genética , Receptores Notch/metabolismo , Transdução de Sinais , Células Tumorais Cultivadas/efeitos dos fármacos
6.
Acad Med ; 92(12): 1715-1722, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29068814

RESUMO

PURPOSE: In an age of globalized medical education, medical school accreditation has been hailed as an approach to external quality assurance. However, accreditation standards can vary widely across national contexts. To achieve recognition by the World Federation for Medical Education (WFME), national accrediting bodies must develop standards suitable for both local contexts and international recognition. This study framed this issue in terms of "glocalization" and aimed to shine light on this complicated multistakeholder process by exploring accreditation in Taiwan, South Korea, and Japan. METHOD: This study employed a comparative case-study design, examining the national standards that three accreditation bodies in East Asia developed using international reference standards. In 2015-2016, the authors conducted document analysis of the English versions of the standards to identify the differences between the national and international reference standards as well as how and why external standards were adapted. RESULTS: Each country's accreditation body sought to balance local needs with global demands. Each used external standards as a template (e.g., Liaison Committee on Medical Education, General Medical Council, or WFME standards) and either revised (Taiwan, South Korea) or annotated (Japan) the standards to fit the local context. Four categories of differences emerged to account for how and why national standards departed from external references: structural, regulatory, developmental, and aspirational. CONCLUSIONS: These countries' glocalization of medical accreditation standards serve as examples for others seeking to bring their accreditation practices in line with global standards while ensuring that local values and societal needs are given adequate consideration.


Assuntos
Acreditação/normas , Currículo , Educação de Graduação em Medicina , Prática Clínica Baseada em Evidências , Garantia da Qualidade dos Cuidados de Saúde , Faculdades de Medicina/normas , Currículo/normas , Educação de Graduação em Medicina/normas , Prática Clínica Baseada em Evidências/normas , Humanos , Japão , Garantia da Qualidade dos Cuidados de Saúde/normas , República da Coreia , Taiwan
7.
Leuk Res ; 30(11): 1385-90, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16780947

RESUMO

A novel lymphoma cell line, designated TMD8 was established from cells of a patient with diffuse large B-cell lymphoma. TMD8 cells expressed HES1 mRNA, suggesting constitutive activation of Notch signaling. TMD8 cells expressed normal-sized Notch1 protein, and showed no mutations in the NOTCH1 gene. Cell growth was suppressed by gamma-secretase inhibitors (GSI). It was reported that GSI suppressed growth of T-cell acute lymphoblastic leukemia (T-ALL) cell lines, which frequently had NOTCH1 mutations. In addition to T-ALL, TMD8 is another unique cell line sensitive to GSI, and is useful to study effects of GSI in molecular targeting therapy.


Assuntos
Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Dipeptídeos/farmacologia , Inibidores Enzimáticos/farmacologia , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/patologia , Oligopeptídeos/farmacologia , Proteínas Adaptadoras de Transdução de Sinal , Fatores de Transcrição Hélice-Alça-Hélice Básicos/efeitos dos fármacos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Proteínas de Ligação ao Cálcio , Sobrevivência Celular/efeitos dos fármacos , Evolução Fatal , Proteínas de Homeodomínio/efeitos dos fármacos , Proteínas de Homeodomínio/genética , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Proteína Jagged-2 , Cariotipagem , Ligantes , Linfoma de Células B/genética , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , Receptor Notch1/genética , Receptor Notch2/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Relação Estrutura-Atividade , Fatores de Transcrição HES-1
8.
Leuk Lymphoma ; 47(11): 2400-3, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17107915

RESUMO

Mutations in the NOTCH1 gene were investigated in 12 primary acute myeloid leukemia (AML) cell samples and eight AML cell lines. Mutations in the genomic DNA were screened using a nested PCR-SSCP analysis and confirmed by direct sequencing. A missense mutation, Pro2439Leu (7316C/T), was found in the PEST domain in one primary AML case. This mutation was different from those previously reported for T-cell acute lymphoblastic leukemia, in which more than half the cases had the mutations. This mutation was not detected in his sample in complete remission, which indicated that the mutation was not a single nucleotide polymorphism. The sample with the mutation expressed the intracellular Notch1 fragment by immunoblotting and HES1 mRNA by reverse transcription-polymerase chain reaction. This is the first paper to present an AML case with NOTCH1 mutation. The precise role of the mutation is to be determined.


Assuntos
Leucemia Mieloide Aguda/genética , Receptor Notch1/genética , Sequência de Bases , Leucemia Mieloide Aguda/metabolismo , Mutação/genética , Receptor Notch1/metabolismo
9.
BMC Public Health ; 6: 85, 2006 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-16584554

RESUMO

BACKGROUND: To examine the type, frequency, severity, and predictors of anemia and its relationship with co-morbid conditions among institutionalized people with intellectual and/or motor disability. METHODS: We conducted a cross-sectional study at a public facility for people with intellectual and/or motor disability in Ibaraki prefecture, Japan. Health checkup data obtained in 2001 from 477 people with intellectual disability (male: 286, average age 40.6 +/- 12.3; female: 191, average age 45.1 +/- 11.6) were retrospectively reviewed. RESULTS: The prevalence of anemia among male participants was higher than in female participants for each disability category (intellectual disability, 41.1%, 4.2%; cerebral palsy, 37.5%, 4.8%; Down's syndrome, 15.0%, 0%; severe motor and intellectual disabilities, 61.9%, 16.7%). Most participants with anemia (93.8 - 100%) showed a normocytic normochromic anemia pattern. Multivariate analysis revealed that factors related to an increase in frequency included sex (male), low body mass index (BMI), use of anticonvulsants or major tranquilizers, and a high zinc sulfate turbidity test (ZTT) value. No clinically diagnosed co-morbid condition was found to be related to the presence of anemia. CONCLUSION: A high frequency of mild normocytic normochromic anemia in institutionalized people with intellectual and/or motor disability was observed, particularly among males. Medications and chronic inflammation may increase the risk of anemia.


Assuntos
Anemia/epidemiologia , Pessoas com Deficiência/estatística & dados numéricos , Institucionalização , Deficiência Intelectual/epidemiologia , Adulto , Anemia/complicações , Comorbidade , Estudos Transversais , Feminino , Inquéritos Epidemiológicos , Humanos , Deficiência Intelectual/complicações , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Instituições Residenciais/estatística & dados numéricos , Fatores de Risco
10.
Exp Hematol ; 33(5): 558-63, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15850833

RESUMO

OBJECTIVE: Notch signaling plays a role in regulating the self-renewal and differentiation of hematopoietic progenitors. Since acute myeloblastic leukemia (AML) originates from dysregulated hematopoietic progenitors, the Notch system may be involved in the abnormal growth. We previously reported that AML cells express Notch proteins. In this study, we examined the effects of recombinant human Notch ligand proteins, Jagged1 and Delta1, on the growth and differentiation of primary AML cells. MATERIALS AND METHODS: AML cells separated from blood from 12 patients were cultured in wells coated with Jagged1, Delta1, or control IgG. The short-term growth was evaluated using a colorimetric assay. The self-renewal capacity was evaluated by the clonogenic cells recovered, which were obtained via a colony assay involving cells cultured with the ligands or control IgG. Differentiation was evaluated by the morphology of the cultured cells and flow cytometric analysis. RESULTS: The ligand stimulation caused three types of response in the short-term growth of the primary AML cells, namely, promotion, suppression, or no significant effect. The self-renewal capacity was suppressed or not significantly affected by the ligands, even in cells showing short-term growth promotion. The ligand stimulation altered blast cells into macrophage-like cells from their morphology and increased the expression of differentiation markers such as CD13 or CD14 in some samples. CONCLUSIONS: The Notch ligands had diverse effects on the short-term growth of primary AML cells. The ligands did not promote the self-renewal capacity of any of the cells examined and instead tended to induce differentiation under the conditions used.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Leucemia Mieloide Aguda/patologia , Proteínas de Membrana/farmacologia , Adulto , Idoso , Proteínas de Ligação ao Cálcio , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Peptídeos e Proteínas de Sinalização Intracelular , Proteína Jagged-1 , Ligantes , Masculino , Proteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Receptores Notch , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Serrate-Jagged , Transdução de Sinais
11.
Leuk Res ; 29(2): 197-203, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15607369

RESUMO

Effects of Notch activation on retinoic acid (RA)-induced differentiation and apoptosis were investigated. NB4, an acute promyelocytic leukemia (APL) cell line, undergoes neutrophilic differentiation and apoptosis by RA. Notch activation induced by a recombinant Notch ligand, Delta-1, did not affect the growth by itself. Treatment with RA plus Delta-1 made part of NB4 cells monocyte-like shaped and reduced the apoptosis. Similar phenomenon was also observed in primary APL cells. RA treatment induced cleavage of caspase-8 and PARP in NB4. Delta-1 suppressed the RA-induced cleavage of them, which may be a possible mechanism through which Delta-1 suppressed the RA-induced apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Proteínas de Membrana/farmacologia , Neutrófilos/citologia , Tretinoína/antagonistas & inibidores , Antígenos CD/metabolismo , Caspase 8 , Caspases/efeitos dos fármacos , Caspases/metabolismo , Diferenciação Celular/fisiologia , Linhagem Celular Tumoral , Linhagem da Célula/efeitos dos fármacos , Citometria de Fluxo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Leucemia Promielocítica Aguda/tratamento farmacológico , Leucemia Promielocítica Aguda/metabolismo , Ligantes , Monócitos/fisiologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Poli(ADP-Ribose) Polimerases/efeitos dos fármacos , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor de Fator Estimulador de Colônias de Macrófagos/genética , Receptores Notch , Tretinoína/metabolismo , Tretinoína/farmacologia
12.
Oncol Rep ; 14(3): 723-6, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16077982

RESUMO

The effect of the recombinant Notch ligand proteins Jagged1 and Delta1 on drug-sensitivity of leukemia and lymphoma cells was examined. Four acute myeloid leukemia (AML) cell lines were cultured in ligand-coated wells and control wells, with cytosine arabinoside (Ara-C), doxorubicin, or mitoxantrone, and nine lymphoid leukemia or lymphoma cell lines were cultured with dexamethasone. The growth was evaluated with a colorimetric assay. The drug-induced growth suppression was slightly reduced by the ligand stimulation in 4 out of 17 combinations of cells versus drugs, such as NB4 cells versus Ara-C. In the remainder, the ligands did not significantly affect the drug-sensitivity. To investigate the possible molecular mechanism of the protective effect, the influence of Jagged1 on Ara-C-induced activation of caspase-3 and PARP, and dephosphorylation of NF-kappaB was examined in NB4 cells. However, Jagged1 did not obviously affect the activation and dephosphorylation. It is known that stromal cells reduce drug-induced cytotoxicity of leukemia cells. According to our results, the role of Notch ligands in the stroma-mediated resistance seems to be minor and occurs only in a limited context. However, the ligand-coated culture-plates are more similar to the microenvironment in human bone marrow than ordinary plates. We will further examine the clinical usefulness of the drug-sensitivity test using the ligand-coated plates.


Assuntos
Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Proteínas de Membrana/farmacologia , Proteínas de Ligação ao Cálcio , Caspase 3 , Caspases/metabolismo , Linhagem Celular Tumoral , Citarabina/farmacologia , Dexametasona/farmacologia , Relação Dose-Resposta a Droga , Doxorrubicina/farmacologia , Ativação Enzimática/efeitos dos fármacos , Humanos , Immunoblotting , Peptídeos e Proteínas de Sinalização Intercelular , Peptídeos e Proteínas de Sinalização Intracelular , Proteína Jagged-1 , Leucemia/metabolismo , Leucemia/patologia , Ligantes , Linfoma/metabolismo , Linfoma/patologia , Proteínas de Membrana/metabolismo , Mitoxantrona/farmacologia , NF-kappa B/metabolismo , Fosforilação/efeitos dos fármacos , Poli(ADP-Ribose) Polimerases/metabolismo , Receptores Notch , Proteínas Recombinantes/farmacologia , Proteínas Serrate-Jagged , Células U937
13.
Int J Oncol ; 22(5): 1073-9, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12684674

RESUMO

The self-renewal and differentiation of hematopoietic progenitors are regulated by the interaction between Notch receptors and Notch ligands. Since AML originates from dysregulated hematopoietic progenitors, some abnormalities in the Notch system may be involved in the abnormal proliferation of AML cells. However, the significance of the Notch system in AML is not known. We examined the functional roles of Notch activation on the in vitro growth of seven human AML cell lines using three kinds of recombinant Notch ligand proteins, Jagged-1, Delta-1 and Delta-4. The ligands significantly affected the growth of two cell lines. In TMD7 cells, Delta proteins promoted the short-term growth, however, suppressing the self-renewal capacity and long-term growth. In OCI/AML-6 cells, Delta proteins suppressed the growth and self-renewal capacity while inducing differentiation into macrophage-like cells. We additionally found that Notch ligands needed to be immobilized on culture wells to affect the cells. These findings were in contrast to our hypothesis that Notch activation in AML cells leads to excessive self-renewal capacity and proliferation. If the Notch system in AML cells is precisely understood, the control of Notch activation will become a novel therapeutic approach for AML.


Assuntos
Proteínas Sanguíneas/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Leucemia Mieloide Aguda/patologia , Proteínas de Membrana/metabolismo , Proteínas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Sítios de Ligação , Proteínas Sanguíneas/genética , Proteínas de Ligação ao Cálcio , Divisão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , Fator Estimulador de Colônias de Granulócitos/farmacologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Proteínas de Homeodomínio/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intracelular , Proteína Jagged-1 , Cinética , Ligantes , Proteínas de Membrana/genética , Proteínas/genética , Proteínas Recombinantes/metabolismo , Proteínas Serrate-Jagged , Células Tumorais Cultivadas
14.
Thromb Res ; 112(5-6): 313-20, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-15041276

RESUMO

Tissue factor (TF) is expressed rapidly by human monocytes exposed to a variety of agonists such as lipopolysaccharide (LPS) or tumor necrosis factor-alpha. Activation of both activator protein-1 (AP-1; c-Jun/c-Fos) and nuclear factor-kappaB (NF-kappaB) pathways is necessary for maximal induction of the TF gene. It has been demonstrated that activation of both AP-1 and NF-kappaB is correlated with the degradation of both phosphorylated c-Jun and inhibitor kappaB (IkappaB) by proteasome. The present study was designed to investigate whether various protease inhibitors, including proteasome inhibitors, affect TF expression in monocytic cells. Protease inhibitors, 3,4-dichloroisocoumarin (DCI), N-tosyl-l-phenylalanine chloromethyl ketone (TPCK), and N-acetyl-Leu-Leu-norleucinal (ALLN) induced TF activity in monocytic cells in a dose- and time-dependent manner at the level of the transcription of the TF gene, which was mediated through inducing phosphorylation of both Jun-N-terminal kinase and p38. The early growth response-1 (Egr-1) pathway was not affected. The NF-kappaB pathway was not activated; rather it was inhibited. These results were distinct from the findings previously reported for LPS-stimulated cells. The present study demonstrated that some protease inhibitors might act as stress and induced TF expression with direct phosphorylation of JNK and p38, followed by phosphorylation and activation of AP-1 in monocytic cells. This evidence may help elucidate further regulatory mechanisms of TF induction, and might have physiological significance for the clinically challenged use of proteasome inhibitors. In addition to phosphorylation of JNK and p38, an unknown signal pathway needs to be clarified for TF induction.


Assuntos
Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Monócitos/metabolismo , Inibidores de Proteases/farmacologia , Tromboplastina/genética , Fator de Transcrição AP-1/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Cinética , Fosforilação , Tromboplastina/efeitos dos fármacos
15.
Int J Mol Med ; 14(2): 223-6, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15254769

RESUMO

It is known that Notch activation promotes the self-renewal of hematopoietic cells. However, we have previously found that the growth of a myeloid leukemia cell line, OCI/AML-6, was suppressed by Notch activation induced by stimulation with a recombinant Notch ligand, Delta-1 protein. We recently found that the growth of another leukemia cell line, THP-1, was also suppressed by the ligands Delta-1 and Jagged-1. In this study, we tried to clarify the cellular and molecular mechanism of the growth suppression induced by Notch activation. Flow cytometric analysis showed that Delta-1 stimulation increased the expression of differentiation markers such as CD11b and CD13 while it decreased the expression of CD117 (c-KIT), a marker for primitive cells in THP-1 cells. In OCI/AML-6 cells, Delta-1 stimulation decreased the expression of CD11b and CD14 and increased CD34 expression. Namely, Delta-1 showed the opposite effects on the differentiation markers of each cell line. Delta-1 stimulation did not increase the binding of annexin V, a marker for apoptotic cells in either cell line. Since the growth of myeloid cells is regulated by MAP kinase and JAK/STAT pathways, we investigated the effects of the ligand stimulation on these pathways. Delta-1 stimulation did not induce the phosphorylation of ERK1/2 and STAT3 proteins in either cell line. Pre-exposure to Delta-1 did not affect the phosphorylation of ERK1/2 and STAT3 induced by G-CSF in OCI/AML-6 cells, either. Namely, it is thought that these pathways are not involved in the growth suppression caused by Notch ligands. Our study revealed several findings on Notch function. However, the precise mechanism remains to be elucidated.


Assuntos
Leucemia Mieloide/metabolismo , Proteínas de Membrana/biossíntese , Proteínas de Membrana/metabolismo , Anexina A5/farmacologia , Apoptose , Antígeno CD11b/biossíntese , Antígenos CD13/biossíntese , Proteínas de Ligação ao Cálcio , Linhagem Celular Tumoral , Proliferação de Células , Inibidores Enzimáticos/farmacologia , Citometria de Fluxo , Fator Estimulador de Colônias de Granulócitos/metabolismo , Humanos , Immunoblotting , Peptídeos e Proteínas de Sinalização Intercelular , Peptídeos e Proteínas de Sinalização Intracelular , Proteína Jagged-1 , Ligantes , Sistema de Sinalização das MAP Quinases , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-kit/biossíntese , Receptores Notch , Proteínas Recombinantes/metabolismo , Proteínas Serrate-Jagged , Fatores de Tempo
16.
Int J Mol Med ; 14(5): 861-6, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15492857

RESUMO

The Notch signaling pathway plays an important role in the regulation of self-renewal and differentiation of hematopoietic progenitors. Tumor necrosis factor (TNF)-alpha induces apoptosis through activation of caspase pathway. A monoblastic leukemia cell line, U937, undergoes apoptosis following stimulation with TNF-alpha. We found that Notch activation induced by a recombinant Notch ligand, Delta-1, reduced the TNF-alpha-induced growth suppression and apoptosis in U937 cells. As the molecular mechanism involved, we showed Delta-1 stimulation partially suppressed the sequential activation of caspase-8, caspase-3, and, PARP induced by TNF-alpha. The TNF-alpha-induced activation of c-Jun N-terminal kinase (JNK), p38, and NF-kappaB was not affected by Delta-1 stimulation. The cells needed to be exposed to Delta-1 prior to TNF-alpha stimulation to reduce the suppressive effect of TNF-alpha. Therefore, we thought that Delta-1 stimulation might reduce the expression of TNF-receptor (R) 1 and proteins to modulate the activation of caspases such as FLIP and XIAP. However, Delta-1 stimulation did not affect their expression. The precise mechanism by which Notch signaling suppresses caspase activation has yet to be determined. This is the first report to show the relationship between Notch activation and TNF-R1 signaling. The findings suggest possible mechanisms by which Notch activation supports cell survival.


Assuntos
Apoptose/efeitos dos fármacos , Caspases/metabolismo , Divisão Celular/efeitos dos fármacos , Receptores de Citocinas/fisiologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Sobrevivência Celular , Ativação Enzimática/efeitos dos fármacos , Humanos , Transdução de Sinais , Células U937
17.
Int J Mol Med ; 13(3): 419-23, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14767573

RESUMO

Notch signaling plays an important role in the regulation of self-renewal and differentiation of hematopoietic cells. Human monoblastic U937 cells undergo differentiation into macrophage-like cells, growth suppression, and apoptosis following stimulation with GM-CSF. We examined the effects of Notch activation induced by Notch ligands on GM-CSF-induced differentiation and apoptosis in U937 cells. Furthermore, the molecular mechanism of the effects was investigated. A recombinant Notch ligand, Delta-1 protein did not affect the growth of U937 cells by itself. GM-CSF-induced growth suppression and apoptosis of U937 cells were partially rescued by incubation with Delta-1. Delta-1 also reduced the GM-CSF-induced differentiation. Incubation with Delta-1 did not affect the expression of GM-CSF receptor. GM-CSF stimulation induced the phosphorylation of ERK1/2 and STAT5 and the cleavage of caspase-8, which were not affected by Delta-1 incubation, either. GM-CSF stimulation induced the cleavage of PARP, which is the key molecule for differentiation and apoptosis. We found that incubation with Delta-1 significantly suppressed the GM-CSF-induced cleavage of PARP. Taken together, we found that Notch activation induced by Delta-1 partially inhibited GM-CSF-induced differentiation, growth suppression, and apoptosis, along with reducing the GM-CSF-induced cleavage of PARP. These findings suggest one of the mechanisms by which Notch activation inhibits differentiation and apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Proteínas de Membrana/farmacologia , Proteínas do Leite , Poli(ADP-Ribose) Polimerases/metabolismo , Caspases/metabolismo , Proteínas de Ligação a DNA/metabolismo , Ativação Enzimática/efeitos dos fármacos , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Ligantes , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosforilação , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/metabolismo , Receptores Notch , Proteínas Recombinantes/farmacologia , Fator de Transcrição STAT5 , Transativadores/metabolismo , Células U937
18.
Respir Physiol Neurobiol ; 130(3): 305-16, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12093627

RESUMO

To elucidate the effect of in-phase chest wall vibration (IPV) during exercise, 17 COPD male patients performed two constant-load exercise tests on a cycle ergometer with and without IPV. The Borg dyspnea score significantly decreased from IPV (-) to IPV (+) (from 13.6+/-2.9 to 12.5+/-2.9, P<0.01). IPV elicited a significant increase in V(O(2)) (P<0.005) and significant decreases in both VE/V(O(2)) (P<0.05) and respiratory frequency (P<0.05), but it did not elicit any changes in VE. The change in Borg score between IPV (+) and IPV (-) showed a significant positive correlation with % predicted V(O(2),max) (r=0.71) and FEV(1)/FVC (r=0.69). Patients in the responsive group (n=11) showed significantly lower FEV(1) (P<0.05) and higher DeltaN(2)/L (P<0.01) than patients in the non-responsive group (n=6). We conclude that IPV reduces dyspnea and improves respiratory efficiency during aerobic exercise in severe COPD.


Assuntos
Dispneia/terapia , Exercício Físico/fisiologia , Doença Pulmonar Obstrutiva Crônica/terapia , Vibração/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Dispneia/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Fusos Musculares/fisiologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Centro Respiratório/fisiologia , Testes de Função Respiratória , Mecânica Respiratória , Músculos Respiratórios/inervação , Músculos Respiratórios/fisiologia
19.
Rinsho Byori ; 50(4): 331-6, 2002 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-12014009

RESUMO

Recent advances in molecular diagnosis in the hematological laboratory have greatly contributed to the diagnosis and treatment of hematologic malignancies, such as leukemia and lymphoma. The pathogenesis of leukemia and lymphoma has been disclosed by the analyses of genetic abnormalities in patients; abnormal gene expression may induce derangement in the control of cellular proliferation. Based on these genetic abnormalities, gene-targeted therapy has been introduced as a new approach to treating hematologic malignancies. We discuss here the usefulness of the molecular diagnosis in clinical hematology.


Assuntos
Leucemia/diagnóstico , Técnicas de Diagnóstico Molecular , Antineoplásicos/uso terapêutico , Benzamidas , Regulação Leucêmica da Expressão Gênica , Marcação de Genes , Terapia Genética/métodos , Humanos , Mesilato de Imatinib , Leucemia/genética , Leucemia/terapia , Neoplasia Residual/diagnóstico , Piperazinas , Prognóstico , Proteínas Tirosina Quinases/antagonistas & inibidores , Pirimidinas/uso terapêutico , Tretinoína/uso terapêutico
20.
Anticancer Res ; 34(6): 2913-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24922654

RESUMO

BACKGROUND: Signaling induced by binding of erythropoietin-producing hepatoma-amplified sequence (EPH) receptors to their cell-surface ephrin ligands is implicated in hematopoiesis and growth of various cancer cells. However, the roles of EPH-ephrin signaling in leukemia have not been elucidated. We investigated the effects of EPHB4 and ephrin B2 on the growth of leukemia cells. MATERIALS AND METHODS: Seven human leukemia cell lines were used to examine the effects of recombinant ephrin B2 and EPHB4 on cell proliferation by colorimetric WST-1 assay and colony assays; on protein tyrosine phosphorylation; and on mRNA expression by reverse transcription-polymerase chain reaction and microarray analysis. RESULTS: In an erythroid leukemia-derived cell line AA, exogenous ephrin B2 induced proliferation and colony formation; in addition, it up-regulated protein tyrosine phosphorylation and the expression of growth-related genes such as FBJ murine osteosarcoma viral oncogene homolog B and v-src avian sarcoma viral oncogene homolog. CONCLUSION: Growth-promoting effects of ephrin B2 were observed in an erythroid leukemia cell line, suggesting that the EPH-ephrin signaling may be involved in the pathology of leukemia.


Assuntos
Proliferação de Células , Efrinas/metabolismo , Leucemia/metabolismo , Leucemia/patologia , Receptores da Família Eph/metabolismo , Biomarcadores Tumorais/genética , Western Blotting , Efrinas/genética , Perfilação da Expressão Gênica , Humanos , Leucemia/genética , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores da Família Eph/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Células Tumorais Cultivadas
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