RESUMO
Cyclin-dependent kinase inhibitor p27Kip1 functions at the nuclear level by binding to cyclin E/cyclin-dependent kinase-2. It was shown that Akt or protein kinase B (Akt/PKB)-dependent phosphorylation of p27Kip1 led to the cytoplasmic mislocalization of p27Kip1, suggesting the potential abrogation of its activity. Here, we evaluated the localization of p27Kip1 protein in leukemic blasts in relation to Akt/PKB phosphorylation and clinical outcomes in acute myelogenous leukemia (AML). Western blot analysis of the nuclear and cytoplasmic fractions revealed a heterogenous localization pattern of p27Kip1 in AML. Cytoplasmic mislocalization of p27Kip1 was significantly associated with the constitutive serine(473) Akt/PKB phosphorylation in AML cells (P < 0.05). Transfection of U937 cells with an expression construct encoding the constitutively active form of Akt/PKB resulted in a remarkable increase in the levels of cytoplasmic p27Kip1. Whereas the transfection of U937 cells with a construct encoding dominant-negative Akt/PKB resulted in a recovery of nuclear localization of p27Kip1. Both the disease-free survival and overall survival are significantly shorter in AML cases with high cytoplasmic to nuclear ratio of p27Kip1 localization compared with the cases with low cytoplasmic to nuclear ratio (P = 0.0353, P = 0.0023, respectively). Multivariate analysis indicated that the cytoplasmic to nuclear ratio of p27Kip1 localization was an independent prognostic variable for both disease-free survival and overall survival (P = 0.043, P = 0.008, respectively). These findings additionally extend our understanding of the role of p27Kip1 in AML, and buttress the case of p27Kip1 mislocalization as a prognostic indicator and Akt/PKB/p27Kip1 pathway as a ready target for antileukemia therapy.
Assuntos
Proteínas de Ciclo Celular/metabolismo , Citoplasma/metabolismo , Inibidores Enzimáticos/metabolismo , Leucemia Mieloide/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Doença Aguda , Adolescente , Adulto , Idoso , Biomarcadores Tumorais , Ciclo Celular , Núcleo Celular/metabolismo , Inibidor de Quinase Dependente de Ciclina p27 , Feminino , Genes Dominantes , Genes Supressores de Tumor , Humanos , Leucemia Mieloide/patologia , Leucemia Mieloide/terapia , Masculino , Pessoa de Meia-Idade , Fosforilação , Prognóstico , Transporte Proteico , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt , Frações Subcelulares , Taxa de Sobrevida , Células U937RESUMO
PURPOSE: The F-box protein S-phase kinase-associated protein 2 (Skp2) positively regulates the G(1)-S phase transition by controlling the stability of several G(1) regulators, such as p27Kip1. However, the clinical significance of Skp2 in patients with acute myelogenous leukemia (AML) remains unknown. EXPERIMENTAL DESIGN: We examined the clinical and biological significance of Skp2 expression in AML and evaluated the relationship between Skp2 and p27Kip1 expression and phosphatase and tensin homologue (PTEN) phosphorylation. RESULTS: Western blot analysis showed that high Skp2 expression was observed in 57 (57.6%) cases and significantly correlated with unfavorable cytogenetics (P = 0.035) but not with age, white blood cell count, serum lactic dehydrogenase level, and the French-American-British subtype. An inverse correlation was not observed between Skp2 and p27Kip1 expression. However, p27Kip1 protein was preferentially localized to cytoplasm in the high-Skp2-expression group. The cytoplasmic to nuclear ratio of p27Kip1 expression was significantly correlated with the levels of Skp2 expression (P < 0.001). The frequency of PTEN phosphorylation was significantly higher in the high-Skp2-expression group compared with the low- Skp2-expression group (P = 0.035). The Skp2 overexpression was significantly associated with shorter disease-free survival and overall survival (P = 0.0386 and P = 0.0369, respectively). Multivariate analysis showed that Skp2 expression was an independent prognostic factor both in the disease-free survival and overall survival. CONCLUSION: These findings suggest that Skp2 expression is an independent marker for a poor prognosis in AML. The presence of a positive correlation between Skp2 and phosphorylated PTEN suggests that an aberration in the PTEN/Skp2 signaling pathway might be operating in AML.
Assuntos
Leucemia Mieloide Aguda/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Proteínas Quinases Associadas a Fase S/biossíntese , Adolescente , Adulto , Idoso , Western Blotting , Ciclo Celular , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Inibidor de Quinase Dependente de Ciclina p27 , Citogenética , Citoplasma/metabolismo , Feminino , Fase G1 , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Fosforilação , Prognóstico , Fase S , Transdução de Sinais , Fatores de Tempo , Resultado do Tratamento , Proteínas Supressoras de Tumor/metabolismoRESUMO
The transcription factor FKHR, which is controlled by Akt-PKB signaling, is involved in regulating cell cycle progression and cell death. In this study, the phosphorylation of FKHR was observed in 45 (73.8%) of 61 patients with acute myeloid leukemia (AML). The phosphorylation of Akt-PKB was found to be significantly associated with phospho-FKHR (P<0.001). Patients with phospho-FKHR had a significantly shorter overall survival than those without (P<0.05). In conclusion, the constitutive phosphorylation of FKHR was observed in the majority of AML, and the detection of phospho-FKHR might provide a new tool for identifying AML patients with an unfavorable outcome.
Assuntos
Proteínas de Ligação a DNA/metabolismo , Regulação Leucêmica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Leucemia Mieloide/metabolismo , Proteínas Serina-Treonina Quinases , Fatores de Transcrição/metabolismo , Doença Aguda , Adolescente , Adulto , Idoso , Western Blotting , Feminino , Proteína Forkhead Box O1 , Fatores de Transcrição Forkhead , Genes Supressores de Tumor , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Humanos , Leucemia Mieloide/patologia , Masculino , Pessoa de Meia-Idade , PTEN Fosfo-Hidrolase , Monoéster Fosfórico Hidrolases/metabolismo , Fosforilação , Prognóstico , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt , Taxa de Sobrevida , Proteínas Supressoras de Tumor/metabolismoRESUMO
As a part of our continuing efforts to develop gene therapy for acute myelogenous leukemia (AML), this study was undertaken to evaluate the possibility of using autologous bone marrow stromal fibroblasts (BMSFs) as a target cell population. Autologous BMSFs in AML were isolated from the stromal layers of long-term bone marrow culture (LTBMC) using immunomagnetic beads. BMSFs exhibited rapid proliferation even in the absence of growth factors. Cultures stimulated with bFGF produced significantly increased numbers of BMSFs than cultures without added growth factors. Using LNC/LacZ retroviral vector, the transduction efficiency of BMSFs was 13+/-4% at a 5 multiplicity of infection (MOI). LNC/interleukin-2 (IL-2)-transduced BMSFs produced between 1200 and 4800pg of IL-2/10(6) cells per 24h. Using adenoviral vector AdV/LacZ, the transduction efficiency was 84+/-10% at 100, and 92+/-8% at a MOI of 1000. Although the addition of basic fibroblast growth factor, epidermal growth factor, or platelet-derived growth factor did not affect the transduction efficiency, they increased the numbers of transduced cells significantly (P<0.01). AdV/IL-2-treated BMSFs produced high levels of IL-2 over the course of 7 days between 9820 and 22,700pg of IL-2/10(6) cells per 24h. Our finding that the genetically engineered autologous BMSFs of AML could be successfully established in vitro implies that BMSFs obtained from LTBMC might be considered as a target cell population for certain types of clinical gene therapy in AML.
Assuntos
Células da Medula Óssea/patologia , Terapia Genética , Leucemia Mieloide Aguda/patologia , Células Estromais/patologia , Transdução Genética , Células Tumorais Cultivadas , Adenoviridae , Células da Medula Óssea/fisiologia , Transplante de Medula Óssea , Engenharia Genética , Terapia Genética/métodos , Vetores Genéticos , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Células Estromais/fisiologia , Fatores de Tempo , Transplante AutólogoRESUMO
Chronic graft-versus-host disease (GVHD) of the liver usually presents as an indolent cholestatic disease. We observed 3 patients in whom chronic GVHD of the liver after allogeneic nonmyeloablative hematopoietic stem cell transplantation (HSCT) presented with marked elevations of serum aminotransferases, clinically resembling acute viral hepatitis. The liver biopsies revealed predominant diffuse lobular injury and degenerative small bile ducts. Prompt administration of high-dose immunosuppressive therapy achieved a rapid improvement of liver enzymes and bilirubin levels. We conclude that a distinct syndrome of chronic hepatic GVHD presenting as an acute hepatitis should be considered as one possible explanation for hepatic dysfunction in patients who receive nonmyeloablative allogeneic HSCT.
Assuntos
Doença Enxerto-Hospedeiro/diagnóstico , Hepatite/diagnóstico , Hepatopatias/diagnóstico , Transplante de Células-Tronco de Sangue Periférico/efeitos adversos , Doença Aguda , Adulto , Diagnóstico Diferencial , Hepatite/etiologia , Humanos , Imunossupressores/uso terapêutico , Linfoma não Hodgkin/terapia , Masculino , Mieloma Múltiplo/terapia , Mielofibrose Primária/terapia , Transaminases/sangue , Transplante HomólogoRESUMO
Expression of the natural killer (NK) cell antigen CD56 is uncommon in malignant lymphoma, but when it is, it is almost exclusively of the non-B cell lineage and show a preference for the nasal and nasopharyngeal region. T/NK cell lymphoma is known to be aggressive and refractory to treatment. It is highly associated with the Epstein-Barr Virus (EBV), but clinical investigations are rarely reported, that is until recently. We report here, on the clinical features and therapeutic outcomes of patients with T/NK cell lymphomas and its association with EBV. We reviewed fifty-four cases with peripheral T cell lymphomas in the upper aerodigestive tract between Jan. 1987 and Aug. 1998 from the Severance Hospital, Yonsei University College of Medicine. The diagnosis of T/NK cell lymphoma was made according to the expression of the NK cell markers, CD56 antigen and cytoplasmic CD3epsilon, in tumor specimens, by immunohistochemistry. Epstein-Barr early region (EBER) RNA was detected using in situ hybridization on paraffin-embedded sections. Among the 54 cases with malignant lymphomas occurring in the upper aerodigestive tract, 20 had T/NK cell lymphoma (37%). The primary sites of T/NK cell lymphomas were the nasal cavity, 12 cases (60%), the tonsils, 4 cases (20%), the nasopharynx, 2 cases (10%), and the oropharynx, 2 case (10%). There were no differences between the features, at diagnosis or therapeutic modalities for patients with T/NK cell lymphoma and non-T/NK cell lymphoma. The complete remission rate of T/NK cell lymphomas was lower than non-T/NK cell lymphomas (65% vs 85%, p=0.02). The overall survival of T/NK cell lymphomas was 13 months (1-74 month), which was significantly lower than non-T/NK cell lymphomas [60.6% with a median follow up of 22 months (1-101 month, p=0.02)]. Disease free survival of T/NK cell lymphomas was 22 months (4-66 month), significantly lower than non-T/NK cell lymphomas [73.8% with a median follow up of 22 months (2-95 month), p=0.04]. The overall survival rates for T/NK cell lymphomas were significantly lower than for EBV positive non-T/NK cell lymphomas (p=0.018). EBER RNA was detected in the paraffin-embedded tissue sections of all T/NK cell lymphomas, compared to only 17.6% (6 of 34 cases) for non- T/NK cell lymphomas. In conclusion, as patients with T/NK cell lymphomas showed poor clinical outcomes, and a high association with EBV positivity, clinical trials with more investigational therapeutic strategies, and further research into the relationship of EBV infection with pathogenesis of T/NK cell lymphoma is warranted.
Assuntos
Neoplasias do Sistema Digestório/terapia , Células Matadoras Naturais , Linfoma de Células T/terapia , Linfoma/terapia , Neoplasias do Sistema Respiratório/terapia , Adulto , Idoso , Neoplasias do Sistema Digestório/virologia , Feminino , Herpesvirus Humano 4/isolamento & purificação , Humanos , Linfoma/virologia , Linfoma de Células T/virologia , Masculino , Pessoa de Meia-Idade , Neoplasias do Sistema Respiratório/virologia , Resultado do TratamentoRESUMO
We report an unusual case of acute myelogenous leukemia in a patient who showed an extramedullary relapse in her uterus, without bone marrow recurrence, two years after an allogeneic bone marrow transplant. She complained of irregular vaginal spotting, and magnetic resonance imaging demonstrated a uterine mass. A biopsy revealed a massive infiltration of immature myeloid cells. A variable number of tandem repeats (VNTR) based on an examination of peripheral blood cells showed full donor chimerism. After receiving chemotherapy, her uterine mass had completely resolved. She has remained in complete remission for more than 6 months. This case suggests that physicians should be aware of the possibility of a uterine relapse in female bone marrow transplant recipients with acute myelogenous leukemia.
Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/terapia , Sarcoma Mieloide/patologia , Neoplasias Uterinas/patologia , Adulto , Feminino , Humanos , Recidiva Local de Neoplasia , Sarcoma Mieloide/etiologia , Neoplasias Uterinas/etiologiaRESUMO
Apicidin, a histone deacetylase inhibitor, is a novel cyclic tetrapeptide with potent antiproliferative activity against various cancer cells. We examined whether apicidin potentiates the imatinib-induced apoptosis of Bcr-Abl-positive human leukaemia cells. In K562 cells, the co-administration of minimally toxic concentrations of imatinib and apicidin (imatinib/apicidin) for 48 h produced a marked increase in mitochondrial damage, processing of caspase cascades and apoptosis. Similar results were observed in leukaemic blasts obtained from patients with chronic myeloid leukaemia in blast crisis. Imatinib/apicidin co-treatment for 48 h resulted in a near complete loss of the full-length XIAP (X-linked inhibitor of apoptosis) protein, with a corresponding increase in the 29-kDa XIAP cleavage product. Both the degradation of XIAP and increased release of second mitochondria-derived activator of caspase/direct IAP-binding protein with low pI (Smac/DIABLO) into the cytosol were abrogated by pretreatment with the caspase-3 inhibitor DEVD-CHO. Imatinib/apicidin co-treatment for 48 h produced a prominent decrease in Bcr-Abl protein levels in a caspase-dependent manner. In summary, these data indicate that apicidin potentiates the imatinib-induced apoptosis of Bcr-Abl-positive leukaemia cells through the enhanced activation of the mitochondria-dependent caspase cascades, accompanied by caspase-dependent downregulation of Bcr-Abl and XIAP. These findings generate a rationale for further investigation of apicidin and imatinib as a potential therapeutic strategy in Bcr-Abl-positive leukaemias.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Caspases/metabolismo , Inibidores Enzimáticos/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Peptídeos Cíclicos/administração & dosagem , Piperazinas/administração & dosagem , Pirimidinas/administração & dosagem , Apoptose/efeitos dos fármacos , Benzamidas , Western Blotting , Sinergismo Farmacológico , Genes abl , Inibidores de Histona Desacetilases , Humanos , Mesilato de Imatinib , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/enzimologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Mitocôndrias/enzimologiaRESUMO
Phosphorylation of PTEN (phosphatase and tensin homologue) affects PTEN protein stability and function. In this study, phosphorylated PTEN (pPTEN) was observed in 45 (73.8%) of 61 cases with acute myeloid leukaemia (AML). Phosphorylation of Akt and its downstream molecules [FKHR; Forkhead (Drosophila) homologue 1; and GSK-3beta; glycogen synthase kinase 3 beta] was significantly associated with pPTEN (P < 0.001). The complete remission rates were not different with respect to pPTEN, but overall survival was significantly shorter in patients with pPTEN (P < 0.05). Constitutive PTEN phosphorylation may add insight into the molecular pathogenesis of AML, and may be a new parameter for an unfavourable outcome.
Assuntos
Leucemia Mieloide/metabolismo , Monoéster Fosfórico Hidrolases/análise , Proteínas Serina-Treonina Quinases , Proteínas Supressoras de Tumor/análise , Doença Aguda , Adolescente , Adulto , Idoso , Western Blotting , Proteínas de Ligação a DNA/metabolismo , Feminino , Proteína Forkhead Box O1 , Fatores de Transcrição Forkhead , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Humanos , Leucemia Mieloide/mortalidade , Masculino , Pessoa de Meia-Idade , Análise Multivariada , PTEN Fosfo-Hidrolase , Fosforilação , Prognóstico , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt , Estatísticas não Paramétricas , Fatores de Transcrição/metabolismoRESUMO
A 20-year-old woman with high-risk acute myelogenous leukaemia was transplanted with granulocyte colony stimulating factor (G-CSF)-mobilized peripheral blood CD34+ haematopoietic stem cells and bone-marrow-derived mesenchymal stem cells (MSC) from her human leucocyte antigen haplotype-mismatched father after myeloablative conditioning therapy. The patient engrafted rapidly and had no acute or chronic graft-versus-host disease. Since transplantation, the patient has shown an enduring trilineage haematological complete response without any evidence of leukaemia relapse at 31 months. We suggest that MSC can be used effectively for genetically haploidentical haematopoietic stem cell transplantation for acute leukaemia.