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2.
Cytokine Growth Factor Rev ; 25(3): 273-83, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24703957

RESUMO

For about four decades, platelet-derived growth factors (PDGF) and their receptors have been the subject of intense research, revealing their roles in embryo development and human diseases. Drugs such as imatinib, which selectively inhibit the tyrosine kinase activity of these receptors, have been approved for the treatment of cancers such as gastrointestinal stromal tumors and chronic eosinophilic leukemia. Today, the interest in these factors is still increasing in relationship with new potential clinical applications in cancer, stroke, fibrosis and infectious diseases. This review focuses on the mechanisms of PDGF receptor signaling, with an emphasis on pathways that are important for disease development. Of particular interest, recent studies revealed significant differences between normal and cancer cells regarding signal transduction by these growth factors.


Assuntos
Tumores do Estroma Gastrointestinal/enzimologia , Síndrome Hipereosinofílica/enzimologia , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Transdução de Sinais , Benzamidas/uso terapêutico , Fibrose/tratamento farmacológico , Fibrose/enzimologia , Fibrose/patologia , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Tumores do Estroma Gastrointestinal/patologia , Humanos , Síndrome Hipereosinofílica/tratamento farmacológico , Síndrome Hipereosinofílica/patologia , Mesilato de Imatinib , Infecções/tratamento farmacológico , Infecções/enzimologia , Infecções/patologia , Leucemia , Piperazinas/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/uso terapêutico , Receptores do Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/enzimologia , Acidente Vascular Cerebral/patologia
3.
PLoS One ; 7(4): e34912, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22523564

RESUMO

The Fip1-like1 (FIP1L1)-platelet-derived growth factor receptor alpha fusion gene (F/P) arising in the pluripotent hematopoietic stem cell (HSC),causes 14% to 60% of patients with hypereosinophilia syndrome (HES). These patients, classified as having F/P (+) chronic eosinophilic leukemia (CEL), present with clonal eosinophilia and display a more aggressive disease phenotype than patients with F/P (-) HES patients. The mechanisms underlying predominant eosinophil lineage targeting and the cytotoxicity of eosinophils in this leukemia remain unclear. Given that the Janus tyrosine kinase (JAK)/signal transducers and activators of transcription (Stat) signaling pathway is key to cytokine receptor-mediated eosinophil development and activated Stat3 and Stat5 regulate the expression of genes involved in F/P malignant transformation, we investigated whether and how JAK proteins were involved in the pathogenesis of F/P-induced CEL. F/P activation of JAK2, Stat3 and Stat5, were confirmed in all the 11 F/P (+) CEL patients examined. In vitro inhibition of JAK2 in EOL-1, primary F/P(+) CEL cells (PC) and T674I F/P Imatinib resistant cells(IR) by either JAK2-specific short interfering RNA (siRNA) or the tryphostin derivative AG490(AG490), significantly reduced cellular proliferation and induced cellular apoptosis. The F/P can enhance the IL-5-induced JAK2 activation, and further results indicated that JAK2 inhibition blocked IL-5-induced cellular migration and activation of the EOL-1 and PC cells in vitro. F/P-stimulation of the JAK2 suppressed cells led to a significantly reduction in Stat3 activation, but relatively normal induction of Stat5 activation. Interestingly, JAK2 inhibition also reduced PI3K, Akt and NF-κB activity in a dose-dependent manner, and suppressed expression levels of c-Myc and Survivin. These results strongly suggest that JAK2 is activated by F/P and is required for F/P stimulation of cellular proliferation and infiltration, possibly through induction of c-Myc and Survivin expression via activation of multiple signaling pathways, including NF-κB, Stat3, and PI3K/Akt.


Assuntos
Eosinófilos/fisiologia , Síndrome Hipereosinofílica/genética , Janus Quinase 2/metabolismo , Proteínas de Fusão Oncogênica/fisiologia , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/fisiologia , Fatores de Poliadenilação e Clivagem de mRNA/fisiologia , Benzamidas , Regulação para Baixo , Ativação Enzimática , Células-Tronco Hematopoéticas/metabolismo , Humanos , Síndrome Hipereosinofílica/enzimologia , Síndrome Hipereosinofílica/fisiopatologia , Mesilato de Imatinib , Interleucina-5/fisiologia , Janus Quinase 2/antagonistas & inibidores , NF-kappa B/metabolismo , Piperazinas/uso terapêutico , Pirimidinas/uso terapêutico , RNA Interferente Pequeno/farmacologia , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT5/antagonistas & inibidores , Fator de Transcrição STAT5/metabolismo , Células Tumorais Cultivadas , Tirfostinas/farmacologia
4.
Mol Biol Rep ; 37(5): 2149-56, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19669929

RESUMO

Leukotactin-1 (Lkn-1)/CCL15 is a CC chemokine that binds to the CCR1 and CCR3. Lkn-1 functions as an essential factor in the migration of monocytes, lymphocytes, and neutrophils. Although eosinophils express both receptors, the role of Lkn-1 in immature eosinophils remains to be elucidated. In this present study, we investigated the contribution of the CCR1-binding chemokines to chemotactic activity and in the differentiation in the human eosinophilic leukemia cell line EoL-1. Lkn-1 induced the stronger migration of EoL-1 cells than other CCR1-binding chemokines such as RANTES/CCL5, MIP-1alpha/CCL3 and HCC-4/CCL16. Lkn-1-induced chemotaxis was inhibited by pertussis toxin, an inhibitor of G(i)/G(o) protein; U73122, an inhibitor of phospholipase C and rottlerin, an inhibitor of protein kinase C delta (PKCdelta). Lkn-1 increased PKCdelta activity, which was partially blocked by the pertussis toxin and U73122. Lkn-1 enhanced the butyric acid-induced differentiation via PKCdelta after binding to the increased CCR1 because Lkn-1 caused EoL-1 cells to change morphologically into mature eosinophil-like cells. Likewise, Lkn-1 increased the expression of both eosinophil peroxidase (EPO) and the major basic protein (MBP). PKCdelta activation due to Lkn-1 is involved in migration, as well as the butyric acid-induced differentiation. This finding contributes to an understanding of CC chemokines in eosinophil biology and to the development of novel therapies for the treatment of eosinophilic disorders. This study suggests the pivotal roles of Lkn-1 in the regulation of the movement and development of eosinophils.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Quimiocinas CC/farmacologia , Síndrome Hipereosinofílica/enzimologia , Síndrome Hipereosinofílica/patologia , Proteínas Inflamatórias de Macrófagos/farmacologia , Proteína Quinase C-delta/metabolismo , Ácido Butírico/farmacologia , Linhagem Celular Tumoral , Ativação Enzimática/efeitos dos fármacos , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Humanos , Receptores CCR1/metabolismo , Fosfolipases Tipo C/metabolismo
5.
Cytokine ; 48(3): 186-95, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19664934

RESUMO

Idiopathic hypereosinophilc syndrome is a disorder associated with clonally eosinophilic proliferation. The importance of FIP1-like-1-platelet-derived growth factor receptor-alpha (FIP1L1-PDGFRA) in the pathogenesis and classification of HES has been recently reported. In this study, we investigated the contribution of monocyte chemoattractant protein-1 (MCP-1)/CCL2 to chemotactic activity and protein kinase C delta (PKC delta in the human eosinophilic leukemia cell line EoL-1. These cells express CCR2 protein among the CC chemokine receptors (CCR1-5). MCP-1 induces strong migration of EoL-1 cells and the chemotaxis signal in response to MCP-1 involves a G(i)/G(o) protein, phospholipase C (PLC), PKC delta, p38 MAPK and NF-kappaB. MCP-1 activates p38 MAPK via G(i)/G(o) protein, PLC and PKC delta cascade. MCP-1 also induces NF-kappaB translocation and the activation is inhibited by PKC delta activation. The increase in the basal expression and activity of PKC delta in EoL-1 cells, compared to normal eosinophils, inhibits apoptosis in EoL-1 cells. Anti-apoptotic mechanism of PKC delta is related to inhibition of caspase 3 and caspase 9, but not to FIP1L1-PDGFRA. PKC delta functions as an anti-apoptotic molecule, and is involved in EoL-1 cell movement stimulated by MCP-1. This study contributes to an understanding of MCP-1 in eosinophil biology and pathogenic mechanism of eosinophilic disorders.


Assuntos
Quimiocina CCL2/metabolismo , NF-kappa B/metabolismo , Proteína Quinase C-delta/metabolismo , Apoptose , Western Blotting , Linhagem Celular Tumoral , Ativação Enzimática , Eosinófilos/enzimologia , Eosinófilos/metabolismo , Citometria de Fluxo , Humanos , Síndrome Hipereosinofílica/enzimologia , Síndrome Hipereosinofílica/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Regulação para Cima
6.
J Biol Chem ; 284(12): 7719-32, 2009 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-19147501

RESUMO

Although leukemogenic tyrosine kinases (LTKs) activate a common set of downstream molecules, the phenotypes of leukemia caused by LTKs are rather distinct. Here we report the molecular mechanism underlying the development of hypereosinophilic syndrome/chronic eosinophilic leukemia by FIP1L1-PDGFRalpha. When introduced into c-Kit(high)Sca-1(+)Lineage(-) cells, FIP1L1-PDGFRalpha conferred cytokine-independent growth on these cells and enhanced their self-renewal, whereas it did not immortalize common myeloid progenitors in in vitro replating assays and transplantation assays. Importantly, FIP1L1-PDGFRalpha but not TEL-PDGFRbeta enhanced the development of Gr-1(+)IL-5Ralpha(+) eosinophil progenitors from c-Kit(high)Sca-1(+)Lineage(-) cells. FIP1L1-PDGFRalpha also promoted eosinophil development from common myeloid progenitors. Furthermore, when expressed in megakaryocyte/erythrocyte progenitors and common lymphoid progenitors, FIP1L1-PDGFRalpha not only inhibited differentiation toward erythroid cells, megakaryocytes, and B-lymphocytes but aberrantly developed eosinophil progenitors from megakaryocyte/erythrocyte progenitors and common lymphoid progenitors. As for the mechanism of FIP1L1-PDGFRalpha-induced eosinophil development, FIP1L1-PDGFRalpha was found to more intensely activate MEK1/2 and p38(MAPK) than TEL-PDGFRbeta. In addition, a MEK1/2 inhibitor and a p38(MAPK) inhibitor suppressed FIP1L1-PDGFRalpha-promoted eosinophil development. Also, reverse transcription-PCR analysis revealed that FIP1L1-PDGFRalpha augmented the expression of C/EBPalpha, GATA-1, and GATA-2, whereas it hardly affected PU.1 expression. In addition, short hairpin RNAs against C/EBPalpha and GATA-2 and GATA-3KRR, which can act as a dominant-negative form over all GATA members, inhibited FIP1L1-PDGFRalpha-induced eosinophil development. Furthermore, FIP1L1-PDGFRalpha and its downstream Ras inhibited PU.1 activity in luciferase assays. Together, these results indicate that FIP1L1-PDGFRalpha enhances eosinophil development by modifying the expression and activity of lineage-specific transcription factors through Ras/MEK and p38(MAPK) cascades.


Assuntos
Diferenciação Celular , Eosinófilos/enzimologia , Síndrome Hipereosinofílica/enzimologia , Sistema de Sinalização das MAP Quinases , Proteínas de Fusão Oncogênica/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Fatores de Poliadenilação e Clivagem de mRNA/metabolismo , Animais , Proteína alfa Estimuladora de Ligação a CCAAT/genética , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Células Cultivadas , Doença Crônica , Citocinas/genética , Citocinas/metabolismo , Eosinófilos/patologia , Fator de Transcrição GATA1/genética , Fator de Transcrição GATA1/metabolismo , Fator de Transcrição GATA2/genética , Fator de Transcrição GATA2/metabolismo , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas , Humanos , Síndrome Hipereosinofílica/genética , Síndrome Hipereosinofílica/metabolismo , Síndrome Hipereosinofílica/patologia , MAP Quinase Quinase 1/genética , MAP Quinase Quinase 1/metabolismo , MAP Quinase Quinase 2/genética , MAP Quinase Quinase 2/metabolismo , Camundongos , Proteínas de Fusão Oncogênica/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Transativadores/genética , Transativadores/metabolismo , Transcrição Gênica/genética , Transplante Homólogo , Fatores de Poliadenilação e Clivagem de mRNA/genética , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
7.
Acta Haematol ; 119(4): 199-206, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18566537

RESUMO

Rearrangements of the genes encoding the fibroblast growth factor receptor 1 (FGFR1) and platelet-derived growth factor receptors (PDGFR) alpha or beta receptor tyrosine kinases are found in a rare but important subset of patients with atypical myeloproliferative disorders that are usually but not always associated with eosinophilia. Chromosomal translocations or other rearrangements at 8p11-12, 4q12 or 5q31-33 give rise to diverse fusion genes encoding chimaeric proteins with constitutive transforming activity. There is considerable molecular heterogeneity with 8 partner genes currently known for FGFR1, 6 for PDGFRA and 17 for PDGFRB. The vast majority of patients with PDGFRA or PDGFRB fusions achieve rapid and durable complete haematological and molecular responses to sustained imatinib therapy. A key ongoing challenge is to define the molecular pathogenesis of the great majority of atypical myeloproliferative disorders for whom the causative lesion remains unknown, since very few of these cases gain any benefit from imatinib or other second-generation inhibitors.


Assuntos
Síndrome Hipereosinofílica/tratamento farmacológico , Síndrome Hipereosinofílica/genética , Proteínas de Fusão Oncogênica/genética , Piperazinas/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/uso terapêutico , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética , Animais , Benzamidas , Cromossomos Humanos/genética , Cromossomos Humanos/metabolismo , Humanos , Síndrome Hipereosinofílica/enzimologia , Mesilato de Imatinib , Proteínas de Fusão Oncogênica/antagonistas & inibidores , Proteínas de Fusão Oncogênica/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptor beta de Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Translocação Genética
9.
Biochem Biophys Res Commun ; 366(4): 1007-11, 2008 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-18086564

RESUMO

The constitutively activated tyrosine kinase Fip1-like 1 (FIP1L1)-platelet-derived growth factor receptor alpha (PDGFRalpha) causes eosinophilic leukemia EoL-1 cells to proliferate. Recently, we demonstrated that histone deacetylase inhibitors suppressed this proliferation and induced the differentiation of EoL-1 cells into eosinophils in parallel with a decrease in the level of FIP1L1-PDGFRalpha. In this study, we analyzed the mechanism by which FIP1L1-PDGFRalpha induces the proliferation and whether the suppression of cell proliferation triggers the differentiation into eosinophils. The FIP1L1-PDGFRalpha inhibitor imatinib inhibited the proliferation of EoL-1 cells and decreased the level of the oncoprotein c-Myc as well as the phosphorylation of extracellular signal-regulated kinase and c-Jun N-terminal kinase (JNK). The proliferation of EoL-1 cells and expression of c-Myc were also inhibited by the MEK inhibitor U0126 and JNK inhibitor SP600125. The expression of the eosinophilic differentiation marker CCR3 was not induced by imatinib. These findings suggest that FIP1L1-PDGFRalpha induces the proliferation of EoL-1 cells through the induction of c-Myc expression via ERK and JNK signaling pathways, but is not involved in the inhibition of differentiation toward mature eosinophils.


Assuntos
Síndrome Hipereosinofílica/patologia , Proteínas de Fusão Oncogênica/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Fatores de Poliadenilação e Clivagem de mRNA/metabolismo , Benzamidas , Butadienos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Síndrome Hipereosinofílica/enzimologia , Mesilato de Imatinib , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Nitrilas/farmacologia , Fosforilação/efeitos dos fármacos , Piperazinas/farmacologia , Proteínas Proto-Oncogênicas c-myc/metabolismo , Pirimidinas/farmacologia , Receptores CCR3/metabolismo
10.
Cancer Res ; 67(8): 3759-66, 2007 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-17440089

RESUMO

An interstitial deletion on chromosome 4q12 resulting in the formation of the FIP1L1-PDGFRA fusion protein is involved in the pathogenesis of imatinib-sensitive chronic eosinophilic leukemia. The molecular mechanisms underlying the development of disease are largely undefined. Human CD34(+) hematopoietic progenitor cells were used to investigate the role of FIP1L1-PDGFRA in modulating lineage development. FIP1L1-PDGFRA induced both proliferation and differentiation of eosinophils, neutrophils, and erythrocytes in the absence of cytokines, which could be inhibited by imatinib. Whereas expression of FIP1L1-PDGFRA in hematopoietic stem cells and common myeloid progenitors induced the formation of multiple myeloid lineages, expression in granulocyte-macrophage progenitors induced only the development of eosinophils, neutrophils, and myeloblasts. Deletion of amino acids 30 to 233 in the FIP1L1 gene [FIP1L1(1-29)-PDGFRA] gave rise to an intermediate phenotype, exhibiting a dramatic reduction in the number of erythrocytes. FIP1L1-PDGFRA and FIP1L1(1-29)-PDGFRA both induced the activation of p38 and extracellular signal-regulated kinase 1/2 (ERK1/2) in myeloid progenitors, whereas signal transducers and activators of transcription 5 (STAT5) and protein kinase B/c-akt were only activated by FIP1L1-PDGFRA. Dominant-negative STAT5 partially inhibited FIP1L1-PDGFRA-induced colony formation, whereas combined inhibition of phosphatidylinositol-3-kinase and ERK1/2 significantly reversed FIP1L1-PDGFRA-induced colony formation. Taken together, these results suggest that expression of FIP1L1-PDFGRA in human hematopoietic progenitors induce a myeloproliferative phenotype via activation of multiple signaling molecules including phosphatidylinositol-3-kinase, ERK1/2, and STAT5.


Assuntos
Células-Tronco Hematopoéticas/metabolismo , Síndrome Hipereosinofílica/metabolismo , Proteínas de Fusão Oncogênica/biossíntese , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/biossíntese , Fatores de Poliadenilação e Clivagem de mRNA/biossíntese , Benzamidas , Diferenciação Celular/fisiologia , Processos de Crescimento Celular/fisiologia , Doença Crônica , Ativação Enzimática , Células-Tronco Hematopoéticas/patologia , Humanos , Síndrome Hipereosinofílica/enzimologia , Síndrome Hipereosinofílica/patologia , Mesilato de Imatinib , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Células Mieloides/metabolismo , Células Mieloides/patologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Proteínas de Fusão Oncogênica/antagonistas & inibidores , Proteínas de Fusão Oncogênica/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Piperazinas/farmacologia , Pirimidinas/farmacologia , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Fator de Transcrição STAT5/metabolismo , Transdução de Sinais , Fatores de Poliadenilação e Clivagem de mRNA/antagonistas & inibidores , Fatores de Poliadenilação e Clivagem de mRNA/metabolismo
11.
Life Sci ; 80(13): 1213-20, 2007 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-17258775

RESUMO

EoL-1 cells differentiate into eosinophils in the presence of n-butyrate, but the mechanism has remained to be elucidated. Because n-butyrate can inhibit histone deacetylases, we hypothesized that the inhibition of histone deacetylases induces the differentiation of EoL-1 cells into eosinophils. In this study, using n-butyrate and two other histone deacetylase inhibitors, apicidin and trichostatin A, we have analyzed the relationship between the inhibition of histone deacetylases and the differentiation into eosinophils in EoL-1 cells. It was demonstrated that apicidin and n-butyrate induced a continuous acetylation of histones H4 and H3, inhibited the proliferation of EoL-1 cells without attenuating the level of FIP1L1-PDGFRA mRNA, and induced the expression of markers for mature eosinophils such as integrin beta7, CCR1, and CCR3 on EoL-1 cells, while trichostatin A evoked a transient acetylation of histones and induced no differentiation into eosinophils. These findings suggest that the continuous inhibition of histone deacetylases in EoL-1 cells induces the differentiation into mature eosinophils.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Eosinófilos/efeitos dos fármacos , Inibidores de Histona Desacetilases , Síndrome Hipereosinofílica/tratamento farmacológico , Acetilação/efeitos dos fármacos , Butiratos/farmacologia , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Eosinófilos/enzimologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Células HL-60 , Histona Desacetilases/metabolismo , Histonas/metabolismo , Humanos , Ácidos Hidroxâmicos/farmacologia , Síndrome Hipereosinofílica/enzimologia , Peptídeos Cíclicos/farmacologia , Fator de Crescimento Derivado de Plaquetas/genética , Fator de Crescimento Derivado de Plaquetas/metabolismo , RNA Mensageiro/metabolismo , Fatores de Poliadenilação e Clivagem de mRNA/genética , Fatores de Poliadenilação e Clivagem de mRNA/metabolismo
12.
Leukemia ; 21(3): 397-402, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17215855

RESUMO

We investigated genetically affected leukemic cells in FIP1L1-PDGFRA+ chronic eosinophilic leukemia (CEL) and in BCR-ABL1+ chronic myeloid leukemia (CML), two myeloproliferative disorders responsive to imatinib. Fluorescence in situ hybridization specific for BCR-ABL1 and for FIP1L1-PDGFRA was combined with cytomorphology or with lineage-restricted monoclonal antibodies and applied in CML and CEL, respectively. In CEL the amount of FIP1L1-PDGFRA+ cells among CD34+ and CD133+ cells, B and T lymphocytes, and megakaryocytes were within normal ranges. Positivity was found in eosinophils, granulo-monocytes and varying percentages of erythrocytes. In vitro assays with imatinib showed reduced survival of peripheral blood mononuclear cells but no reduction in colony-forming unit growth medium (CFU-GM) growth. In CML the BCR-ABL1 fusion gene was detected in CD34+/CD133+ cells, granulo-monocytes, eosinophils, erythrocytes, megakaryocytes and B-lymphocytes. Growth of both peripheral blood mononuclear cells and CFU-GM was inhibited by imatinib. This study provided evidence for marked differences in the leukemic masses which are targeted by imatinib in CEL or CML, as harboring FIP1L1-PDGFRA or BCR-ABL1.


Assuntos
Proteínas de Fusão bcr-abl/análise , Síndrome Hipereosinofílica/patologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Células-Tronco Neoplásicas/enzimologia , Proteínas de Fusão Oncogênica/análise , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/análise , Fatores de Poliadenilação e Clivagem de mRNA/análise , Antígeno AC133 , Antígenos CD/análise , Antígenos CD34/análise , Antineoplásicos/uso terapêutico , Benzamidas , Linhagem da Célula , Doença Crônica , Células Clonais/enzimologia , Resistência a Medicamentos , Eosinófilos/enzimologia , Eritrócitos/enzimologia , Proteínas de Fusão bcr-abl/antagonistas & inibidores , Glicoforinas/análise , Glicoproteínas/análise , Granulócitos/enzimologia , Células-Tronco Hematopoéticas/enzimologia , Humanos , Síndrome Hipereosinofílica/tratamento farmacológico , Síndrome Hipereosinofílica/enzimologia , Síndrome Hipereosinofílica/genética , Mesilato de Imatinib , Imunofenotipagem , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/enzimologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Subpopulações de Linfócitos/enzimologia , Megacariócitos/enzimologia , Monócitos/enzimologia , Células Mieloides/enzimologia , Proteínas de Fusão Oncogênica/antagonistas & inibidores , Peptídeos/análise , Piperazinas/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/uso terapêutico , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores , Ensaio Tumoral de Célula-Tronco , Inativação do Cromossomo X , Fatores de Poliadenilação e Clivagem de mRNA/antagonistas & inibidores
13.
Int J Hematol ; 83(5): 433-8, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16787876

RESUMO

A 38-year-old Japanese man was referred to our hospital in June 2003 for treatment of acute respiratory failure with severe eosinophilia. Idiopathic hypereosinophilic syndrome had been diagnosed in 1994. However, karyotypic examination of bone marrow cells revealed that chromosomal translocation with t(4;10)(q12;p11) had occurred in 2000, and chronic eosinophilic leukemia was diagnosed. At admission, the patient's respiratory condition was extremely serious, and mechanical support was necessary. Despite treatment with steroid pulse therapy and cytarabine, the blood eosinophil count did not decrease, and the patient's respiratory condition worsened. After obtaining informed consent, we administered imatinib mesylate at a dose of 200 mg/day for 2 days and 100 mg/day for 3 days. The blood eosinophil count decreased dramatically over 5 days, and the patient's condition rapidly improved, such that the patient could be discharged. In this case, we performed molecular analysis using peripheral blood. The FIP1-like 1 (FIP1L1)-platelet-derived growth factor receptor alpha (PDGFRalpha) fusion transcript was found with the reverse transcriptase polymerase chain reaction analysis. In this case, eosinophilia was possibly caused by constitutive activation of tyrosine kinase produced by the FIP1L1-PDGFRalpha fusion transcript.


Assuntos
Síndrome Hipereosinofílica/tratamento farmacológico , Síndrome Hipereosinofílica/enzimologia , Proteínas de Fusão Oncogênica/antagonistas & inibidores , Piperazinas/administração & dosagem , Inibidores de Proteínas Quinases/administração & dosagem , Pirimidinas/administração & dosagem , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores , Fatores de Poliadenilação e Clivagem de mRNA/antagonistas & inibidores , Adulto , Povo Asiático , Benzamidas , Cromossomos Humanos Par 10/genética , Cromossomos Humanos Par 4/genética , Doença Crônica , Ativação Enzimática/efeitos dos fármacos , Eosinofilia/tratamento farmacológico , Eosinofilia/enzimologia , Eosinofilia/genética , Seguimentos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Humanos , Síndrome Hipereosinofílica/genética , Mesilato de Imatinib , Contagem de Leucócitos , Masculino , Proteínas de Fusão Oncogênica/biossíntese , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA Neoplásico/biossíntese , RNA Neoplásico/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Fatores de Tempo , Translocação Genética/genética , Fatores de Poliadenilação e Clivagem de mRNA/biossíntese
15.
Haematologica ; 90(5): 596-601, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15921374

RESUMO

BACKGROUND AND OBJECTIVES: According to WHO criteria, the idiopathic hypereosinophilic syndrome (HES) is defined as persistent eosinophilia (>1.5x10(9)/L) without underlying causes, which is associated with signs or symptoms of organ involvement. Increased bone marrow blasts (>5%) or cytogenetic/genetic markers indicate chronic eosinophilic leukemia (CEL). A cryptic deletion of 4q12, i.e. del(4)(q12), producing the FIP1L1/PDGFRA fusion gene, identifies a distinct CEL subgroup (4q-/CEL). Our aims were: a) to use interphase-fluorescent in situ hybridization (FISH) to detect the cryptic 4q12 deletion; b) to compare the clinico-hematologic features of 4q-/CEL with other HES; c) to investigate whether PDGFRB, FGFR1, ABL1, and ETV6-activated tyrosine kinases are rearranged in CEL/HES. DESIGN AND METHODS: This multicenter study included 20 patients fulfilling the WHO criteria for HES and 6 patients without signs/symptoms of end-organ involvement. Double-color FISH was applied in all cases to investigate del(4)(q12). Further interphase-FISH assessed whether PDGFRB/5q33, FGFR1/8p11, ABL1/9q34, and ETV6/12p13, undergo rearrangements in HES. RESULTS: Ten of the 26 patients (9 males and 1 female) had a cryptic del(4)(q12)-FIP1L1/PDGFRA which was confirmed by reverse transcription polymerase chain reaction (RT-PCR) analysis in four. Hepatomegaly and splenomegaly were significantly more frequent in these 10 than in the other 16 patients. Seven of these 10 patients received imatinib mesylate therapy and all achieved hematologic remission. In 3 of the patients interphase-FISH and RT-PCR demonstrated cytogenetic and molecular remission. Improvements were observed in signs and symptoms of cardiac and central nervous system involvement in 2 and 1 patient, respectively. Rearrangements of PDGFRB, FGFR1, ABL1, or ETV6 were not detected in this study. INTERPRETATION AND CONCLUSIONS: FISH is a reliable diagnostic test for differentiating 4q-/CEL from other forms of HES, allowing an early diagnosis of good responders to imatinib mesylate therapy. For the first time we show that PDGFRB, FGFR1, ABL1 and ETV6 are not rearranged in HES and 4q-/CEL cases we studied.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 4/genética , Síndrome Hipereosinofílica/genética , Proteínas de Fusão Oncogênica/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Fatores de Poliadenilação e Clivagem de mRNA/genética , Corticosteroides/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Benzamidas , Células da Medula Óssea/ultraestrutura , Criança , Cromossomos Humanos Par 4/ultraestrutura , Quimioterapia Combinada , Feminino , Humanos , Síndrome Hipereosinofílica/enzimologia , Mesilato de Imatinib , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Proteínas de Fusão Oncogênica/análise , Especificidade de Órgãos , Piperazinas/farmacologia , Piperazinas/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Tirosina Quinases/genética , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/análise , Estudos Retrospectivos , Análise de Sobrevida , Fatores de Poliadenilação e Clivagem de mRNA/análise
17.
Cell Biochem Funct ; 22(2): 105-12, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15027099

RESUMO

The human eosinophilic leukemia cell line, EoL-1, differentiated with butyrate as an eosinophilic cellular model was evaluated for peroxidase-dependent tyrosine nitration. Butyrate suppressed cell growth and induced eosinophilic granules in EoL-1 cells after 9 days of culture. Peroxidase activity was detected biochemically and histochemically from 3-day cultures and it increased in a time dependent manner. This peroxidase activity was inhibited by cyanide. Nitrotyrosine formation catalysed by peroxidase using hydrogen peroxide and nitrite was detected at a high level similar to that of mature eosinophils. However, no expression of eosinophil peroxidase (EPO) was detected by RT-PCR or immunocytochemistry. In contrast, the induction of myeloperoxidase (MPO) by butyrate was clearly detected by RT-PCR, Northern blot, and immunocytochemical staining. These results suggest that butyrate induces MPO rather than EPO in EoL-1 cells and that the formation of nitrotyrosine in butyrate-induced cells is dependent on MPO.


Assuntos
Síndrome Hipereosinofílica/enzimologia , Peroxidase/metabolismo , Tirosina/análogos & derivados , Tirosina/biossíntese , Butiratos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Grânulos Citoplasmáticos/efeitos dos fármacos , Peroxidase de Eosinófilo , Humanos , Síndrome Hipereosinofílica/tratamento farmacológico , Síndrome Hipereosinofílica/metabolismo , Imuno-Histoquímica , Peroxidases/metabolismo
18.
Ann Hematol ; 83(7): 477-80, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-14986065

RESUMO

Many cases of hypereosinophilia, formerly classified as hypereosinophilic syndrome, can now be characterized as chronic eosinophilic leukemia (CEL) based on the demonstration of characteristic genetic markers indicating clonality of hematopoiesis. Here we report on a 33-year-old male patient with central nervous system manifestations of CEL and an excellent response to low-dose imatinib (Glivec). Molecular analysis demonstrated a constitutive activation of the platelet-derived growth factor receptor-alpha (PDGFR-A) as the mechanism of responsiveness to imatinib.


Assuntos
Antineoplásicos/uso terapêutico , Encéfalo/patologia , Inibidores Enzimáticos/uso terapêutico , Síndrome Hipereosinofílica/tratamento farmacológico , Síndrome Hipereosinofílica/etiologia , Infiltração Leucêmica/patologia , Piperazinas/uso terapêutico , Pirimidinas/uso terapêutico , Adulto , Braço , Azatioprina/uso terapêutico , Benzamidas , Ataxia Cerebelar/etiologia , Córtex Cerebelar/patologia , Cefaleia/etiologia , Humanos , Síndrome Hipereosinofílica/complicações , Síndrome Hipereosinofílica/enzimologia , Síndrome Hipereosinofílica/patologia , Mesilato de Imatinib , Imunossupressores/uso terapêutico , Imageamento por Ressonância Magnética , Masculino , Transtornos da Memória/etiologia , Proteínas de Fusão Oncogênica/antagonistas & inibidores , Paresia/etiologia , Lobo Parietal/patologia , Poliarterite Nodosa/tratamento farmacológico , Poliarterite Nodosa/etiologia , Prednisona/uso terapêutico , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores , Indução de Remissão , Vertigem/etiologia , Fatores de Poliadenilação e Clivagem de mRNA/antagonistas & inibidores
19.
Curr Opin Hematol ; 11(1): 51-7, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14676627

RESUMO

PURPOSE OF REVIEW: The idiopathic hypereosinophilic syndrome is a rare hematologic disorder characterized by sustained unexplained eosinophilia with associated end-organ damage and by a striking male predominance. The first insights into the molecular etiology of this heterogeneous disease were obtained from a "bedside-to-bench" approach. Successful empiric treatment of patients with the hypereosinophilic syndrome with the selective tyrosine kinase inhibitor imatinib mesylate (Gleevec, Novartis) ultimately led to the discovery of the FIP1L1-PDGFRalpha fusion kinase in about half of the hypereosinophilic syndrome cases. RECENT FINDINGS: The FIP1L1-PDGFRA fusion gene is generated by a cryptic interstitial chromosomal deletion, del(4)(q12q12), which indicates that these cases are clonal hematopoietic malignancies and should be reclassified as chronic eosinophilic leukemias based on current World Health Organization recommendations. In addition, the FIP1L1-PDGFRA fusion gene was also identified in cases with systemic mast cell disease. In vitro and in vivo studies confirmed that FIP1L1-PDGFRalpha is a therapeutic target of imatinib, forming a rational basis for the treatment of FIP1L1-PDGFRA positive chronic eosinophilic leukemia and mastocytosis with imatinib. Similar to BCR-ABL-positive leukemias, resistance to imatinib due to point mutations in the PDGFRalpha kinase domain may develop. We have explored strategies to circumvent resistance to imatinib using alternative tyrosine kinase inhibitors such as PKC412. SUMMARY: The discovery of the FIP1L1-PDGFRA fusion gene in the hypereosinophilic syndrome is an example of the power of clinical translational research and identifies interstitial chromosomal deletion as a novel mechanism to generate oncogenic tyrosine kinase fusion genes.


Assuntos
Síndrome Hipereosinofílica/enzimologia , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Fatores de Poliadenilação e Clivagem de mRNA/genética , Sequência de Aminoácidos , Humanos , Síndrome Hipereosinofílica/diagnóstico , Síndrome Hipereosinofílica/genética , Masculino , Dados de Sequência Molecular , Proteínas de Fusão Oncogênica , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/fisiologia , Proteínas Recombinantes de Fusão/metabolismo , Deleção de Sequência , Fatores de Poliadenilação e Clivagem de mRNA/fisiologia
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