Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23
Filtrar
1.
Bone Marrow Transplant ; 45(12): 1719-27, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20208571

RESUMO

Late-onset noninfectious pulmonary complications (LONIPCs) are life threatening for allogeneic hematopoietic SCT (allo-HSCT) recipients. However, the impact of LONIPCs on survival has not been properly evaluated and little is known about treatment efficacy. We retrospectively investigated 290 allo-HSCT recipients in our institute and reviewed the clinical aspects of 44 patients who had been diagnosed with LONIPCs. LONIPCs were significantly associated with higher rates of chronic GVHD (P<0001) and nonrelapse mortality (P=0.013), and lower rates of relapse (P=0.009). As a result of these effects, OS was significantly worse in those with LONIPCs (P=0.003). This result differs from a previous report. We then assessed short-term treatment response and final outcome. These results were defined by radiological findings, subjective symptoms, oxygen requirement and survival. Use of inhaled and systemic steroids did not affect either short-term response or final outcomes. However, administration of systemic corticosteroids earlier than at 21 days (median interval of time from onset of symptoms to systemic corticosteroids administration) was associated with a better outcome (P=0.054 for short-term response, and 0.016 for final outcome). Our study indicates that LONIPCs reduce OS, and early intervention with systemic corticosteroids may be effective.


Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Doenças Pulmonares Intersticiais/tratamento farmacológico , Doenças Pulmonares Intersticiais/etiologia , Adolescente , Adulto , Idoso , Feminino , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida , Resultado do Tratamento , Adulto Jovem
2.
J Chemother ; 22(1): 54-7, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20227994

RESUMO

Combined therapy of rituximab, etoposide, methylprednisolone, high-dose cytarabine, and cisplatin (R-ESHAP) has been one of the most frequently used salvage regimens for relapsed/refractory non-Hodgkin's lymphoma. In 2002, we introduced the modified R-ESHAP regimen in which cisplatin was switched to carboplatin. we evaluated the safety and effectiveness of this modified regimen by reviewing the records of 35 patients who had been administered R-ESHAP. Our cohort included 21 patients with diffuse large b cell lymphoma (DLBCL) and 14 patients with follicular lymphoma (FL). The overall response rate (ORR) was 48% for DLBCL and 93% for FL. The overall survival (OS) for patients with DLBCL was 51% with a median follow-up of 11 months, and 91% for patients with Fl with a median follow-up of 36 months. Our study indicates that modified R-ESHAP is an effective and safe salvage regimen for relapsed/refractory FL, however, its efficacy for relapsed DLBCL is limited.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma de Células B/tratamento farmacológico , Adulto , Idoso , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Murinos , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Citarabina/administração & dosagem , Citarabina/efeitos adversos , Dexametasona/administração & dosagem , Dexametasona/efeitos adversos , Etoposídeo/administração & dosagem , Etoposídeo/efeitos adversos , Feminino , Mobilização de Células-Tronco Hematopoéticas , Humanos , Linfoma de Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Recidiva , Rituximab
5.
Leukemia ; 21(5): 992-7, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17315020

RESUMO

The unbalanced translocation, der(1;7)(q10;p10), is one of the characteristic cytogenetic abnormalities found in myelodysplastic syndromes (MDS) and other myeloid neoplasms. Although described frequently with very poor clinical outcome and possible relationship with monosomy 7 or 7q- (-7/7q-), this recurrent cytogenetic abnormality has not been explored fully. Here we analyzed retrospectively 77 cases with der(1;7)(q10;p10) in terms of their clinical and cytogenetic features, comparing with other 46 adult -7/7q- cases without der(1;7)(q10;p10). In contrast with other -7/7q- cases, where the abnormality tends to be found in one or more partial karyotypes, der(1;7)(q10;p10) represents the abnormality common to all the abnormal clones and usually appears as a sole chromosomal abnormality during the entire clinical courses, or if not, is accompanied only by a limited number and variety of additional abnormalities, mostly trisomy 8 and/or loss of 20q. der(1;7)(q10;p10)-positive MDS cases showed lower blast counts (P<0.0001) and higher hemoglobin concentrations (P<0.0075) at diagnosis and slower progression to acute myeloid leukemia (P=0.0043) than other -7/7q- cases. der(1;7)(q10;p10) cases showed significantly better clinical outcome than other -7/7q cases (P<0.0001). In conclusion, der(1;7)(q10;p10) defines a discrete entity among myeloid neoplasms, showing unique clinical and cytogenetic characteristics.


Assuntos
Aberrações Cromossômicas , Leucemia Mieloide Aguda/genética , Síndromes Mielodisplásicas/genética , Transtornos Mieloproliferativos/genética , Translocação Genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Cromossomos Humanos Par 1 , Cromossomos Humanos Par 7 , Feminino , Transplante de Células-Tronco Hematopoéticas , Humanos , Leucemia Mieloide Aguda/patologia , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/patologia , Transtornos Mieloproliferativos/patologia , Estudos Retrospectivos
6.
Bone Marrow Transplant ; 36(9): 813-9, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16151428

RESUMO

Clinical impact of high-grade (HG) cytomegalovirus (CMV) antigenemia after hematopoietic stem cell transplantation has not been clarified. Therefore, in order to investigate the risk factors and outcome for HG-CMV antigenemia, we retrospectively analyzed the records of 154 Japanese adult patients who underwent allogeneic hematopoietic stem cell transplantation for the first time from 1995 to 2002 at the University of Tokyo Hospital. Among 107 patients who developed positive CMV antigenemia at any level, 74 received risk-adapted preemptive therapy with ganciclovir (GCV), and 17 of these developed HG-antigenemia defined as > or = 50 positive cells per two slides. The use of systemic corticosteroids at > or = 0.5 mg/kg/day at the initiation of GCV was identified as an independent significant risk factor for HG-antigenemia. Seven of the 17 HG-antigenemia patients developed CMV disease, with a cumulative incidence of 49.5%, which was significantly higher than that in the low-grade antigenemia patients (4%, P<0.001). However, overall survival was almost equivalent in the two groups. In conclusion, the development of HG-antigenemia appeared to depend on the profound immune suppression of the recipient. Although CMV disease frequently developed in HG-antigenemia patients, antiviral therapy could prevent a fatal outcome.


Assuntos
Antígenos Virais/sangue , Infecções por Citomegalovirus/sangue , Citomegalovirus , Neoplasias Hematológicas/sangue , Transplante de Células-Tronco Hematopoéticas , Adolescente , Adulto , Antivirais/administração & dosagem , Infecções por Citomegalovirus/etiologia , Infecções por Citomegalovirus/prevenção & controle , Feminino , Ganciclovir/administração & dosagem , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/terapia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Transplante Homólogo
8.
Bone Marrow Transplant ; 33(10): 1043-7, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15064691

RESUMO

The value of pre-transplant factors for predicting the development of cardiac complications after transplantation has been inconsistent among studies. We analyzed the impact of pre-transplant factors on the incidence of severe cardiac complications in 164 hematopoietic stem cell transplant recipients. We identified eight patients (4.8%) who experienced grade III or IV cardiac complications according to the Bearman criteria. Seven died of cardiac causes a median of 3 days after the onset of cardiac complications. On univariate analysis, both the cumulative dose of anthracyclines and the use of anthracyclines within 60 days before transplantation affected the incidence of severe cardiac complications (P=0.0091 and 0.011). The dissociation of heart rate and body temperature, which reflects "relative tachycardia", was also associated with a higher incidence of cardiac complications (P=0.024). None of the variables obtained by electrocardiography or echocardiography were useful for predicting cardiac complications after transplantation, although the statistical power might not be sufficient to detect the usefulness of ejection fraction. On a multivariate analysis, the cumulative dose of anthracyclines was the only independent significant risk factor for severe cardiac complications. We conclude that the cumulative dose of anthracyclines is the most potent predictor of cardiac complications and the administration of anthracyclines should be avoided within two months before transplantation.


Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Taquicardia/diagnóstico , Adulto , Antraciclinas/uso terapêutico , Temperatura Corporal , Terapia Combinada , Ciclofosfamida/uso terapêutico , Ecocardiografia , Eletrocardiografia , Feminino , Frequência Cardíaca , Neoplasias Hematológicas/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Complicações Pós-Operatórias , Estudos Retrospectivos , Fatores de Risco , Taquicardia/etiologia , Condicionamento Pré-Transplante , Transplante Homólogo/métodos , Irradiação Corporal Total
9.
Bone Marrow Transplant ; 33(5): 549-52, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14716350

RESUMO

We retrospectively compared the incidence of acute graft-versus-host disease (GVHD) before and after September 1999, when we changed the mode of cyclosporine A (CsA) administration from twice-daily infusions (TD) (n=58) to continuous infusion (CIF) (n=71). The incidence of grade II-IV acute GVHD in the CIF group (56%) was significantly higher than that in the TD group (27%, P=0.00022). Multivariate analysis identified only two independent significant risk factors for the development of grade II-IV acute GVHD; CIF of CsA (relative risk 2.59, 95% CI 1.46-4.60, P=0.0011) and the presence of HLA mismatch (2.01, 95% CI 1.15-3.53, P=0.014). The incidence of relapse was significantly lower in the CIF group when adjusted for disease status before transplantation (0.41, 95% CI 0.18-0.95, P=0.038), which resulted in better disease-free survival in high-risk patients (43 vs 16% at 2 years, P=0.039), but not in standard-risk patients (72 vs 80%, P=0.45). CIF of CsA with a target level of 250-400 ng/ml may not be appropriate for GVHD prophylaxis in standard-risk patients.


Assuntos
Ciclosporina/administração & dosagem , Doença Enxerto-Hospedeiro/epidemiologia , Transplante de Células-Tronco Hematopoéticas , Imunossupressores/administração & dosagem , Leucemia/terapia , Doença Aguda , Adulto , Ciclosporina/efeitos adversos , Feminino , Humanos , Imunossupressores/efeitos adversos , Incidência , Infusões Intravenosas , Nefropatias/epidemiologia , Leucemia/epidemiologia , Masculino , Análise Multivariada , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
10.
Bone Marrow Transplant ; 32(12): 1175-9, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14647272

RESUMO

Late-onset hemorrhagic cystitis (LHC) after hematopoietic stem cell transplantation (HSCT) is mainly caused by viral infections. We retrospectively analyzed the records of 141 Japanese adult patients who underwent a first allogeneic HSCT from 1995 to 2002. In all, 19 patients developed LHC a median of 51 days after HSCT. Adenovirus (AdV) was detected in the urine of 10 LHC patients, of whom eight had AdV type 11. Five of the six available serum samples from these patients were also positive for AdV type 11, but the detection of AdV in serum was not associated with a worse outcome. Male sex and the development of grade II-IV acute graft-versus-host disease were identified as independent significant risk factors for LHC. Male predominance was detected in LHC after HSCT, as has been previously shown in children with AdV-induced acute HC. The detection of AdV DNA in serum did not predict a poor outcome.


Assuntos
Cistite/epidemiologia , Transplante de Células-Tronco Hematopoéticas , Hemorragia/epidemiologia , Infecções por Adenoviridae/complicações , Infecções por Adenoviridae/epidemiologia , Adenovírus Humanos/isolamento & purificação , Adolescente , Adulto , Idoso , Anemia Aplástica/complicações , Anemia Aplástica/terapia , Vírus BK/isolamento & purificação , Bussulfano/efeitos adversos , Ciclofosfamida/efeitos adversos , Cistite/etiologia , Cistite/virologia , Feminino , Doença Enxerto-Hospedeiro/epidemiologia , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/terapia , Hemorragia/etiologia , Hemorragia/virologia , Humanos , Terapia de Imunossupressão/efeitos adversos , Imunossupressores/efeitos adversos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/complicações , Síndromes Mielodisplásicas/terapia , Infecções por Polyomavirus/complicações , Infecções por Polyomavirus/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Distribuição por Sexo , Condicionamento Pré-Transplante/efeitos adversos , Transplante Homólogo , Irradiação Corporal Total/efeitos adversos
11.
Leukemia ; 17(6): 1112-20, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12764377

RESUMO

ETS variant gene 6 (ETV6)/translocation, ETS, leukemia (TEL)-involving chromosomal translocations are frequently observed in various hematologic neoplasms. We describe here a novel ETV6-involving translocation, t(12;13)(p13;q14), found in the case of acute lymphoblastic leukemia, in which ETV6 fused with a previously unknown gene, named Twelve-thirteen Translocation Leukemia gene (TTL), at 13q14. TTL was weakly but ubiquitously expressed in normal human tissues as detected by reverse transcribed-PCR. Three TTL splicing forms were identified, TTL-T from a human testis cDNA library, with an open-reading frame of 402 bp encoding 133 amino acids (aa), and TTL-B1 and -B2 from a human brain cDNA library. These proteins have no homology to known proteins. In leukemic cells from the patient, both reciprocal fusion transcripts, ETV6/TTL and TTL/ETV6, were expressed. The predominant fusion transcript, TTL/ETV6-1, encodes a predicted 530 aa fusion protein containing 89 aa of the N-terminal TTL fusing to the helix-loop-helix domain and ETS-binding domain of ETV6. Although the function of TTL is yet to be elucidated, our findings will provide another insight into the molecular pathogenesis of leukemia having ETV6-involving translocations.


Assuntos
Cromossomos Humanos Par 12 , Cromossomos Humanos Par 13 , Proteínas de Ligação a DNA/genética , Proteínas de Fusão Oncogênica/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Proteínas Repressoras/genética , Translocação Genética , Processamento Alternativo , Sequência de Aminoácidos , Sequência de Bases , Southern Blotting , Encéfalo , Clonagem Molecular , Primers do DNA/química , Proteínas de Ligação a DNA/metabolismo , Biblioteca Gênica , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Proteínas de Fusão Oncogênica/metabolismo , Isoformas de Proteínas , Proteínas Proto-Oncogênicas c-ets , RNA Neoplásico/sangue , RNA Neoplásico/genética , RNA Neoplásico/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Testículo , Variante 6 da Proteína do Fator de Translocação ETS
12.
Oncogene ; 20(1): 88-96, 2001 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-11244507

RESUMO

The Smad family proteins are critical components of the transforming growth factor (TGF)-beta signaling pathway. TGF-beta is a multipotent cytokine that elicits many biological functions. In particular, TGF-beta exhibits effects on the cell cycle manifested by G1-phase arrest, differentiation, or apoptosis of several target cells, suggesting that disruption of TGF-beta signaling pathway could be involved in cancer formation. Here we show one missense mutation of the Smad4 gene in the MH1 domain (P102L) and one frame shift mutation resulting in termination in the MH2 domain (Delta(483 - 552)) in acute myelogeneous leukemia. Both of the mutated Smad4 proteins lack transcriptional activities. Concomitant expression of the P102L mutant with wild-type Smad4 inactivates wild-type Smad4 through inhibiting its DNA-binding ability. The Delta(483 - 552) mutant blocks nuclear translocation of wild-type Smad4 and thus disrupts TGF-beta signaling. This is the first report showing that mutations in the Smad4 gene are associated with the pathogenesis of acute myelogeneous leukemia and the obtained results should provide useful insights into the mechanism whereby disruption of TGF-beta signaling pathway could lead to acute myelogeneous leukemia. Oncogene (2001) 20, 88 - 96.


Assuntos
Proteínas de Ligação a DNA/genética , Genes Supressores de Tumor/fisiologia , Leucemia Mieloide Aguda/genética , Mutação , Transdução de Sinais/genética , Transativadores/genética , Animais , Células COS , Divisão Celular/genética , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , DNA/metabolismo , Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/fisiologia , Ativação Enzimática/genética , Regulação Neoplásica da Expressão Gênica , Vetores Genéticos/metabolismo , Inibidores do Crescimento/antagonistas & inibidores , Inibidores do Crescimento/fisiologia , Células HL-60 , Humanos , Células Jurkat , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Regiões Promotoras Genéticas/genética , Ligação Proteica/genética , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Inibidores de Serina Proteinase/farmacologia , Proteína Smad3 , Proteína Smad4 , Frações Subcelulares/metabolismo , Transativadores/antagonistas & inibidores , Transativadores/biossíntese , Transativadores/metabolismo , Transativadores/fisiologia , Ativação Transcricional/genética , Fator de Crescimento Transformador beta/antagonistas & inibidores , Fator de Crescimento Transformador beta/fisiologia , Células Tumorais Cultivadas
13.
Blood ; 96(9): 3154-60, 2000 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11049997

RESUMO

The AML1 gene encodes a DNA-binding protein that contains the runt domain and is the most frequent target of translocations associated with human leukemias. Here, point mutations of the AML1 gene, V105ter (single-letter amino acid code) and R139G, (single-letter amino acid codes) were identified in 2 cases of myelodysplastic syndrome (MDS) by means of the reverse transcriptase-polymerase chain reaction single-strand conformation polymorphism method. Both mutations are present in the region encoding the runt domain of AML1 and cause loss of the DNA-binding ability of the resultant products. Of these mutants, V105ter has also lost the ability to heterodimerize with polyomavirus enhancer binding protein 2/core binding factor beta (PEBP2beta/CBFbeta). On the other hand, the R139G mutant acts as a dominant negative inhibitor by competing with wild-type AML1 for interaction with PEBP2beta/CBFbeta. This study is the first report that describes mutations of AML1 in patients with MDS and the mechanism whereby the mutant acts as a dominant negative inhibitor of wild-type AML1.


Assuntos
Proteínas de Ligação a DNA/genética , Leucemia/genética , Síndromes Mielodisplásicas/genética , Mutação Puntual , Proteínas Proto-Oncogênicas , Fatores de Transcrição/genética , Substituição de Aminoácidos , Sítios de Ligação , Subunidade alfa 2 de Fator de Ligação ao Core , Proteínas de Ligação a DNA/química , Dimerização , Humanos , Proteínas de Neoplasias/genética , Polimorfismo Conformacional de Fita Simples , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição AP-2 , Fatores de Transcrição/química
14.
Jpn J Cancer Res ; 89(1): 33-9, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9510473

RESUMO

Defects in DNA mismatch repair mechanisms, including frameshift mutations of the hMSH6 and hMSH3 genes at their (C)8 and (A)8 tracks, respectively, have been shown to be associated with human malignancies. To clarify the possible involvement of these mutations in hematopoietic malignancies, we screened a total of forty-four human leukemia and lymphoma cell lines for mutations in the hMSH6 and hMSH3 genes, as well as in other genes required for DNA replication or repair, by polymerase chain reaction single-strand conformation polymorphism analysis and sequencing analysis. Frameshift mutations at the (C)8 track of the hMSH6 gene were detected in two cell lines established from lymphoid leukemias. These two cell lines had no wild-type alleles, and both of them showed microsatellite instability. This is the first report that describes mutations and inactivation of the hMSH6 gene in hematological malignancies, suggesting that defects of the hMSH6 gene may be associated with development of hematological malignancies.


Assuntos
Proteínas de Ligação a DNA , Mutação da Fase de Leitura , Proteínas Fúngicas/genética , Leucemia/genética , Proteínas de Saccharomyces cerevisiae , Sequência de Bases , DNA Polimerase III/genética , Reparo do DNA/genética , Humanos , Células Jurkat , Linfoma/genética , Repetições de Microssatélites , Proteína 2 Homóloga a MutS , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Proteínas Proto-Oncogênicas/genética , Células Tumorais Cultivadas
15.
Leukemia ; 11(6): 863-5, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9177441

RESUMO

Mutations of the N-ras oncogene and p53 tumor suppressor gene were simultaneously investigated in bone marrow cells from 44 patients with myelodysplastic syndrome (MDS) or MDS-derived leukemia by single-strand conformation polymorphism (SSCP) analysis followed by direct sequencing. The mutations of the N-ras gene were detected only in two cases with MDS-derived leukemia. Three patients with MDS-derived leukemia and one with refractory anemia with excess of blasts exhibited five mutations of the p53 gene. No concomitant mutations of both genes were observed in our study, suggesting that alterations of both genes could play an important role in the progression of MDS in a non-cooperative manner.


Assuntos
Genes p53 , Genes ras , Síndromes Mielodisplásicas/genética , Mutação Puntual , Polimorfismo Conformacional de Fita Simples , Anemia Refratária/genética , Anemia Refratária com Excesso de Blastos/genética , Medula Óssea/patologia , Éxons , Humanos , Leucemia Mielomonocítica Crônica/genética , Síndromes Mielodisplásicas/imunologia , Síndromes Mielodisplásicas/patologia , Reação em Cadeia da Polimerase/métodos
17.
Leukemia ; 11 Suppl 3: 358-60, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9209389

RESUMO

In order to clarify the significance of p16 gene (CDKN2) inactivation and its disease specificity among hematopoietic tumors, configurations of the p16 gene as well as those of the adjacent p15 and interferon alpha (IFN alpha) genes were examined in primary hematopoietic tumors. Loss of the p16 gene is frequent in and highly specific to lymphoid tumors among hematopoietic tumors. Gene deletions but not minute mutations should be the predominant mechanism of p16 gene inactivation in these types of tumors. The p16 gene is most frequently deleted among the p16, p15 and IFN alpha genes and thus should be the target of deletions in this locus. Deletions of the p16 gene were frequently observed in tumors carrying chromosome 9p abnormalities while a significant number of cases showed loss of the p16 gene without chromosome 9p abnormalities. So far inactivation of p53 and Rb tumor suppressors have also been found in lymphoid tumors. In our study, we detected homozygous deletions of p16 gene in 20%, loss of Rb protein in 28%, and p53 gene alterations in 8% of lymphoid tumors. Notably, 44% of lymphoid tumors showed inactivation of at least one of the three tumor suppressors, suggesting these tumor suppressors are important for lymphoid tumorigenesis. Inactivations of these tumor suppressors should independently occur in development of lymphoid tumors.


Assuntos
Proteínas de Transporte/genética , Aberrações Cromossômicas , Transtornos Cromossômicos , Cromossomos Humanos Par 9 , Quinases Ciclina-Dependentes/antagonistas & inibidores , Genes Supressores de Tumor , Neoplasias Hematológicas/genética , Leucemia/genética , Proteínas Proto-Oncogênicas , Proteínas de Transporte/metabolismo , Mapeamento Cromossômico , Quinase 4 Dependente de Ciclina , Inibidor p16 de Quinase Dependente de Ciclina , Inibidores Enzimáticos/metabolismo , Genes do Retinoblastoma , Genes p53 , Homozigoto , Humanos , Interferon-alfa/genética , Deleção de Sequência
18.
Blood ; 89(5): 1740-7, 1997 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-9057658

RESUMO

Defects in genes involved in DNA mismatch repair have been detected in both hereditary and sporadic tumors of colon, endometrium, and ovary and suggested to be associated with tumorigenesis. To investigate disruptions of the mismatch repair system in hematological malignancies, we examined alterations of the human mutL homologue 1 (hMLH1) gene, a member of the mismatch repair gene family, in a total of 43 human leukemia and lymphoma cell lines, by polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) and sequencing analyses. Mutations of the hMLH1 gene were detected in three cell lines established from lymphoid leukemias. Moreover, Northern and Western blot analyses showed that expression of hMLH1 transcript or protein was abrogated in these three leukemia cell lines. Further studies for microsatellite loci showed that these cell lines without hMLH1 expression showed microsatellite instability. This is the first report that describes mutations and inactivation of the hMLH1 gene in human leukemia cells, suggesting that disruption of DNA mismatch repair system may play an important role in the development of human lymphoid leukemias.


Assuntos
Leucemia/genética , Linfoma/genética , Mutação , Proteínas de Neoplasias/genética , Proteínas Adaptadoras de Transdução de Sinal , Proteínas de Transporte , Reparo do DNA/genética , Humanos , Proteína 1 Homóloga a MutL , Proteínas Nucleares , Reação em Cadeia da Polimerase , Células Tumorais Cultivadas
19.
Oncogene ; 13(1): 183-91, 1996 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-8700545

RESUMO

Overexpression of the Evi-1 gene appears to be a consistent feature of the 3q21q26 syndrome, an association of myeloid leukemias/myelodysplastic syndrome with a specific chromosomal aberration involving both 3q21 and 3q26, such as t(3;3)(q21;q26) or inv(3)(q21q26). The rearrangement in 3q26 has been reported to occur near the Evi-1 locus, implicating that it is the critical gene deregulated in the 3q21q26 syndrome. Here we present a structural abnormality of Evi-1 protein in a case with the 3q21q26 syndrome. In this case carrying typical inv(3)(q21q26), the 3q26 breakpoint is located within an intron of the Evi-1 gene, and resulted in overexpression of normally unexpressed, an aberrant form of Evi-1 protein, in which the C-terminal 44 amino acids of wild-type Evi-1 protein were truncated and replaced by five amino acids. The truncated Evi-1 protein is shown to increase AP1 activity when expressed in NIH3T3 cells as its wild-type counterpart. We also show that the origin of this peculiar type of rearrangement of the Evi-1 gene is not an artifact during establishment of the cell line, but is the event that occurred in the primary leukemic cells. Our results strongly support that the primary target for the 3q21q26 syndrome is the Evi-1 gene, and provide the first evidence that the structurally altered Evi-1 gene may be involved in the 3q21q26 syndrome.


Assuntos
Inversão Cromossômica , Cromossomos Humanos Par 3/genética , Proteínas de Ligação a DNA/genética , Regulação Leucêmica da Expressão Gênica , Proteínas de Neoplasias/genética , Proto-Oncogenes , Fatores de Transcrição , Células 3T3 , Sequência de Aminoácidos , Animais , Sequência de Bases , Crise Blástica/patologia , Linhagem Celular Transformada , DNA Complementar/genética , Humanos , Hibridização in Situ Fluorescente , Íntrons/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Proteína do Locus do Complexo MDS1 e EVI1 , Camundongos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Síndrome , Células Tumorais Cultivadas
20.
Blood ; 87(12): 4949-58, 1996 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-8652807

RESUMO

It is now evident that the cell cycle machinery has a variety of elements negatively regulating cell cycle progression. However, among these negative regulators in cell cycle control, only 4 have been shown to be consistently involved in the development of human cancers as tumor suppressors: Rb (Retinoblastoma susceptibility protein), p53, and two recently identified cyclin-dependent kinase inhibitors, p16INK4A/MTS1 and p15INK4B/MTS2. Because there are functional interrelations among these negative regulators in the cell cycle machinery, it is particularly interesting to investigate the multiplicity of inactivations of these tumor suppressors in human cancers, including leukemias/lymphomas. To address this point, we examined inactivations of these four genes in primary lymphoid malignancies by Southern blot and polymerase chain reaction-single-strand conformation polymorphism analyses. We also analyzed Rb protein expression by Western blot analysis. The p16INK4A and p15INK4B genes were homozygously deleted in 45 and 42 of 230 lymphoid tumor specimens, respectively. Inactivations of the Rb and p53 genes were 27 of 91 and 9 of 173 specimens, respectively. Forty-one (45.1%) of 91 samples examined for inactivations of all four tumor suppressors had one or more abnormalities of these four tumor-suppressor genes, indicating that dysregulation of cell cycle control is important for tumor development. Statistical analysis of interrelations among impairments of these four genes indicated that inactivations of the individual tumor-suppressor genes might occur almost independently. In some patients, disruptions of multiple tumor-suppressor genes occurred; 4 cases with p16INK4A, p15INK4B, and Rb inactivations; 2 cases with p16INK4A, p15INK4B, and p53 inactivations; and 1 case with Rb and p53 inactivations. It is suggested that disruptions of multiple tumor suppressors in a tumor cell confer an additional growth advantage on the tumor.


Assuntos
Proteínas de Ciclo Celular , Ciclo Celular/genética , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor , Leucemia/genética , Linfoma não Hodgkin/genética , Proteínas Supressoras de Tumor , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Proteínas de Transporte/biossíntese , Proteínas de Transporte/genética , Pré-Escolar , Aberrações Cromossômicas , Inibidor de Quinase Dependente de Ciclina p15 , Inibidor p16 de Quinase Dependente de Ciclina , Feminino , Fase G1/genética , Regulação Leucêmica da Expressão Gênica , Genes do Retinoblastoma , Genes p53 , Humanos , Recém-Nascido , Leucemia/patologia , Linfoma não Hodgkin/patologia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mieloma Múltiplo/genética , Mieloma Múltiplo/patologia , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Proteína do Retinoblastoma/biossíntese , Proteína Supressora de Tumor p53/biossíntese
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA