RESUMO
Oncogenic subtypes in childhood B-cell precursor acute lymphoblastic leukemia (BCP-ALL) are used for risk stratification. However, a significant number of BCP-ALL patients are still genetically unassigned. Using array-comparative genomic hybridization in a selected BCP-ALL cohort, we characterized a recurrent V(D)J-mediated intragenic deletion of the ERG gene (ERG(del)). A breakpoint-specific PCR assay was designed and used to screen an independent non-selected cohort of 897 children aged 1-17 years treated for BCP-ALL in the EORTC-CLG 58951 trial. ERG(del) was found in 29/897 patients (3.2%) and was mutually exclusive of known classifying genetic lesions, suggesting that it characterized a distinct leukemia entity. ERG(del) was associated with higher age (median 7.0 vs. 4.0 years, P=0.004), aberrant CD2 expression (43.5% vs. 3.7%, P<0.001) and frequent IKZF1 Δ4-7 deletions (37.9% vs. 5.3%, P<0.001). However, ERG(del) patients had a very good outcome, with an 8-year event-free survival (8-y EFS) and an 8-year overall survival of 86.4% and 95.6%, respectively, suggesting that the IKZF1 deletion had no impact on prognosis in this genetic subtype. Accordingly, within patients with an IKZF1 Δ4-7 deletion, those with ERG(del) had a better outcome (8-y EFS: 85.7% vs. 51.3%; hazard ratio: 0.16; 95% confidence interval: 0.02-1.20; P=0.04). These findings have implications for further stratification including IKZF1 status.
Assuntos
Deleção de Genes , Fator de Transcrição Ikaros/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Transativadores/genética , Adolescente , Sequência de Bases , Criança , Pré-Escolar , Primers do DNA , Feminino , Humanos , Lactente , Masculino , Reação em Cadeia da Polimerase , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patologia , Regulador Transcricional ERGAssuntos
Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Neoplasia Residual/diagnóstico , Neoplasia Residual/genética , Proteínas de Fusão Oncogênica/genética , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Criança , Pré-Escolar , Cromossomos Humanos Par 16/genética , Feminino , França , Rearranjo Gênico , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Neoplasia Residual/tratamento farmacológico , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento , Adulto JovemAssuntos
Proteínas de Fusão bcr-abl/fisiologia , Genes Supressores de Tumor/fisiologia , Fator de Transcrição Ikaros/fisiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/etiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Animais , Feminino , Citometria de Fluxo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Taxa de SobrevidaRESUMO
Recently, we and others described a new chromosomal rearrangement, that is, inv(7)(p15q34) and t(7;7)(p15;q34) involving the T-cell receptor beta (TCRbeta) (7q34) and the HOXA gene locus (7p15) in 5% of T-cell acute lymphoblastic leukemia (T-ALL) patients leading to transcriptional activation of especially HOXA10. To further address the clinical, immunophenotypical and molecular genetic findings of this chromosomal aberration, we studied 330 additional T-ALLs. This revealed TCRbeta-HOXA rearrangements in five additional patients, which brings the total to 14 cases in 424 patients (3.3%). Real-time quantitative PCR analysis for HOXA10 gene expression was performed in 170 T-ALL patients and detected HOXA10 overexpression in 25.2% of cases including all the cases with a TCRbeta-HOXA rearrangement (8.2%). In contrast, expression of the short HOXA10 transcript, HOXA10b, was almost exclusively found in the TCRbeta-HOXA rearranged cases, suggesting a specific role for the HOXA10b short transcript in TCRbeta-HOXA-mediated oncogenesis. Other molecular and/or cytogenetic aberrations frequently found in subtypes of T-ALL (SIL-TAL1, CALM-AF10, HOX11, HOX11L2) were not detected in the TCRbeta-HOXA rearranged cases except for deletion 9p21 and NOTCH1 activating mutations, which were present in 64 and 67%, respectively. In conclusion, this study defines TCRbeta-HOXA rearranged T-ALLs as a distinct cytogenetic subgroup by clinical, immunophenotypical and molecular genetic characteristics.
Assuntos
Proteínas de Homeodomínio/genética , Leucemia-Linfoma de Células T do Adulto/genética , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Adolescente , Adulto , Criança , Deleção Cromossômica , Inversão Cromossômica , Feminino , Rearranjo Gênico do Linfócito T , Proteínas Homeobox A10 , Humanos , Imunofenotipagem , Leucemia-Linfoma de Células T do Adulto/patologia , Leucemia-Linfoma de Células T do Adulto/fisiopatologia , Masculino , Pessoa de Meia-Idade , Receptor Notch1/genética , Ativação Transcricional , Translocação GenéticaAssuntos
Toxina Diftérica/farmacologia , Interleucina-3/farmacologia , Leucemia-Linfoma de Células T do Adulto/tratamento farmacológico , Leucemia-Linfoma de Células T do Adulto/metabolismo , Receptores de Interleucina-3/metabolismo , Proteínas Recombinantes de Fusão/farmacologia , Divisão Celular , Humanos , Imunofenotipagem , Subunidade alfa de Receptor de Interleucina-3 , Leucemia-Linfoma de Células T do Adulto/patologiaRESUMO
Strong expression of at least one of the three D-type cyclins is common in human cancers. While the cyclin D1 and D3 genes (CCND1 and CCND3) are recurrently involved in genomic rearrangements, especially in B-cell lymphoid neoplasias, no clear involvement of the cyclin D2 gene (CCND2) has been reported to date. Here, we identified chromosomal translocations targeting the CCND2 locus at 12p13, and the T-cell receptor beta (TCRB) or the TCRA/D loci in T-cell acute lymphoblastic leukemias (T-ALLs). Expression analysis demonstrated dramatic cyclin D2 overexpression in the translocated cases (n=3) compared to other T-ALLs (total, n=89). In order to evaluate dysregulation in T-ALL with respect to normal T-cell differentiation, we analyzed CCND2 expression in normal purified human thymic subpopulations. CCND2 levels were downregulated through progression from the early stages of human T-cell differentiation, further suggesting that the massive and sustained expression in the CCND2-rearranged T-ALL cases was oncogenic. Association with other oncogene expression (TAL1, HOXAs, or TLX3/HOX11L2), NOTCH1 activating mutations, and/or CDKN2A/p16/ARF deletion, showed that cyclin D2 dysregulation could contribute to multi-event oncogenesis in various T-ALL groups. This report is the first clear evidence of a direct involvement of cyclin D2 in human cancer due to recurrent somatic genetic alterations.
Assuntos
Cromossomos Humanos Par 12/genética , Ciclinas/biossíntese , Ciclinas/genética , Leucemia-Linfoma de Células T do Adulto/genética , Receptores de Antígenos de Linfócitos T/genética , Translocação Genética , Adulto , Separação Celular , Criança , Ciclina D2 , Análise Citogenética , Análise Mutacional de DNA , Rearranjo Gênico , Humanos , Leucemia-Linfoma de Células T do Adulto/diagnóstico , Leucemia-Linfoma de Células T do Adulto/metabolismoAssuntos
Neoplasias/genética , Neoplasias/prevenção & controle , Proteínas de Fusão Oncogênica/genética , Reação em Cadeia da Polimerase/instrumentação , Reação em Cadeia da Polimerase/métodos , Europa (Continente) , Proteínas de Fusão bcr-abl/genética , Humanos , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Acute lymphoblastic leukemia (ALL) is the most common cancer in children. In recent years, the outcome has been globally improved by current therapies, but it remains poor in patients with high, persistent residual disease following the first course of chemotherapy, prompting evaluation of the possible beneficial effects of immunotherapy protocols. In this study, we hypothesized that the disruption of two immunoregulatory pathways controlling the auto-reactive T cell response might synergize with dendritic cell-based immunotherapy of the disease, which is considered to be poorly immunogenic. In this study, we used TAL1xLMO1 leukemia cells adoptively transferred in mice, to generate murine leukemia with poorly immunogenic cells as a model for human T-ALL. Subsequently, these animals were treated with several different immunotherapeutic protocols. We compared the efficiency of a classical, dendritic cell-based immunotherapy (injection of dendritic cells loaded with tumor-derived antigenic products), to a combined treatment associating injection of antigen-loaded dendritic cells and disruption of the two immunoregulatory pathways: CD25+ suppressive T cells and cytotoxic T lymphocyte-associated antigens (CTLA-4). We show that this combined treatment resulted in cure, concomitantly with in vivo generation of immune memory, and TNF-alpha secretion. This study demonstrates that the disruption of these two immunoregulatory pathways synergized with immunostimulation by dendritic cells loaded with tumor-derived antigens, and paves the way for the testing of this combination in clinical trials.
Assuntos
Imunoterapia Adotiva , Leucemia-Linfoma Linfoblástico de Células T Precursoras/imunologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/terapia , Transdução de Sinais/imunologia , Linfócitos T/imunologia , Animais , Antígenos CD/metabolismo , Antígenos de Neoplasias/administração & dosagem , Antígeno CTLA-4 , Linhagem Celular Tumoral , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Células Dendríticas/transplante , Modelos Animais de Doenças , Memória Imunológica , Subunidade alfa de Receptor de Interleucina-2/biossíntese , Depleção Linfocítica , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Linfócitos T/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Despite modern regimen of chemotherapy, one-third of children with acute lymphoblastic leukaemia relapse. Recent studies have shown that a high level of minimal residual disease (MRD) at the end of induction is associated with an increased risk of relapse. We have developed and validated a real-time PCR method (RQ-PCR) to quantify MRD. We monitored 57 patients using IgH and TCR (Vdelta2Ddelta3) genes rearrangements as PCR targets. RQ-PCR was performed with a primer and a TaqMan probe designed to consensus sequences in VH segments in combination with one allele specific oligonucleotide primer complementary to the junctionnal region. A sensitivity of 10(-4) was reached for 72% of the IgH alleles (n = 50) and for 54,5% of the Vdelta2Ddelta3 alleles (n = 22). We compared the results with those obtained by competitive PCR in 53 patients: no discordance between the two methods was observed. Seventeen patients were found positive (32%) and 27 negative (51%) with both techniques and 9 children (17%) were positive only with TaqMan technology. RQ-PCR is more sensitive and more specific than competitive PCR. We thus propose that RQ-PCR might be used in first intention for MRD analysis.
Assuntos
Assistência ao Convalescente/métodos , DNA de Neoplasias , Monitoramento de Medicamentos/métodos , Reação em Cadeia da Polimerase/métodos , Leucemia-Linfoma Linfoblástico de Células Precursoras B , Adolescente , Assistência ao Convalescente/normas , Criança , Pré-Escolar , DNA de Neoplasias/análise , DNA de Neoplasias/genética , Monitoramento de Medicamentos/normas , Feminino , Rearranjo Gênico de Cadeia Pesada de Linfócito B/efeitos dos fármacos , Rearranjo Gênico de Cadeia Pesada de Linfócito B/genética , Humanos , Lactente , Neoplasia Residual , Seleção de Pacientes , Reação em Cadeia da Polimerase/normas , Leucemia-Linfoma Linfoblástico de Células Precursoras B/sangue , Leucemia-Linfoma Linfoblástico de Células Precursoras B/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamento farmacológico , Prognóstico , Indução de Remissão , Fatores de Risco , Sensibilidade e Especificidade , Taq PolimeraseRESUMO
We report the case of a 30-year-old HIV-infected man admitted for a meningeal syndrome and a zoster rash. The CSF had cytological features suggesting a primary CNS lymphoma (PCNSL). The large lymphoid cells had a fine chromatin with nucleoli, a basophilic cytoplasm with azurophilic granules and high mitotic activity. Several arguments demonstrated the viral origin of the meningitis: the large lymphoid cells were of T origin with no evidence of clonal TCR gamma gene rearrangement. The PCR was positive for Varicella-Zoster Virus (VZV) and EBV DNA. Clinical evolution was favorable under acyclovir. We should be cautious in the differential diagnosis between viral meningitis and PCNSL.
Assuntos
Neoplasias do Sistema Nervoso Central/virologia , Herpes Zoster/diagnóstico , Herpesvirus Humano 3/patogenicidade , Linfoma Relacionado a AIDS/virologia , Meningite Viral/diagnóstico , Adulto , Neoplasias do Sistema Nervoso Central/líquido cefalorraquidiano , Neoplasias do Sistema Nervoso Central/diagnóstico , DNA Viral/líquido cefalorraquidiano , Diagnóstico Diferencial , Infecções por Vírus Epstein-Barr/líquido cefalorraquidiano , Infecções por Vírus Epstein-Barr/virologia , Ganciclovir/uso terapêutico , Herpes Zoster/líquido cefalorraquidiano , Herpes Zoster/fisiopatologia , Herpesvirus Humano 3/isolamento & purificação , Herpesvirus Humano 4/isolamento & purificação , Humanos , Linfoma Relacionado a AIDS/líquido cefalorraquidiano , Linfoma Relacionado a AIDS/diagnóstico , Masculino , Reação em Cadeia da PolimeraseRESUMO
We have previously shown correction of X-linked severe combined immunodeficiency [SCID-X1, also known as gamma chain (gamma(c)) deficiency] in 9 out of 10 patients by retrovirus-mediated gamma(c) gene transfer into autologous CD34 bone marrow cells. However, almost 3 years after gene therapy, uncontrolled exponential clonal proliferation of mature T cells (with gammadelta+ or alphabeta+ T cell receptors) has occurred in the two youngest patients. Both patients' clones showed retrovirus vector integration in proximity to the LMO2 proto-oncogene promoter, leading to aberrant transcription and expression of LMO2. Thus, retrovirus vector insertion can trigger deregulated premalignant cell proliferation with unexpected frequency, most likely driven by retrovirus enhancer activity on the LMO2 gene promoter.
Assuntos
Proteínas de Ligação a DNA/genética , Terapia Genética/efeitos adversos , Vetores Genéticos , Leucemia-Linfoma de Células T do Adulto/etiologia , Metaloproteínas/genética , Retroviridae/genética , Imunodeficiência Combinada Severa/terapia , Linfócitos T/fisiologia , Proteínas Adaptadoras de Transdução de Sinal , Ensaios Clínicos como Assunto , Células Clonais/fisiologia , Regulação da Expressão Gênica , Técnicas de Transferência de Genes , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/fisiologia , Humanos , Lactente , Proteínas com Domínio LIM , Mutagênese Insercional , Regiões Promotoras Genéticas , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas , Proto-Oncogenes , Receptores de Interleucina-2/genética , Retroviridae/fisiologia , Transcrição Gênica , Integração Viral , Replicação ViralRESUMO
FLT3 internal tandem duplications (FLT3-ITDs) are present in nearly 25% of patients with AML and have been associated with poor response to conventional therapy and poor outcome. We retrospectively evaluated the effect of reinforced courses of chemotherapy on the prognostic value of FLT3-ITDs in 159 AML patients prospectively enrolled in the ALFA-9000 trial, which randomly compared three reinforced induction regimens (standard 3+7 including high-dose daunorubicin, double induction, and timed-sequential therapy). FLT3-ITD was present in 40/159 (25%) blast samples and associated with high WBC (P = 0.002) and cytogenetics (P < 0.001) with a higher incidence (35%) in patients with a normal karyotype. There was no difference in CR rate between FLT3-wt and FLT3-ITD patients (80% vs 78%). Relapse-free survival (RFS) was similar in both groups (5-year RFS, 33% vs 32%; P = 0.41), even after adjustment for age, sex, WBC, cytogenetics, and treatment arm. A trend to a worse survival was observed in the FLT3-ITD group (estimated 5-year OS, 23% vs 37%; P = 0.09), mainly in patients with a normal karyotype. This was associated with a dramatic outcome in relapsing FLT3-ITD patients (estimated 3-year post-relapse survival, 0% vs 27%; P = 0.04). These results suggest that the bad prognosis associated with FLT3-ITDs in AML might be partly overcome using reinforced chemotherapy. Early detection of FLT3 mutations might thus be useful to intensify induction as well as post-remission therapy in FLT3-ITD patients.
Assuntos
Leucemia Mieloide/tratamento farmacológico , Leucemia Mieloide/genética , Proteínas Proto-Oncogênicas/genética , Receptores Proteína Tirosina Quinases/genética , Sequências de Repetição em Tandem/genética , Doença Aguda , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , DNA de Neoplasias/análise , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prognóstico , Estudos Prospectivos , Receptores de Superfície Celular/genética , Estudos Retrospectivos , Fator de Células-Tronco/genética , Taxa de Sobrevida , Resultado do Tratamento , Tirosina Quinase 3 Semelhante a fmsRESUMO
T-cell prolymphocytic leukemia (T-PLL) is a rare malignant proliferation of lymphoid cells with a postthymic phenotype. Previous cytogenetic and molecular studies reported complex karyotypes with recurrent chromosomal abnormalities, including translocations involving either TCL1 at 14q32.1 or MTCP1 at Xq28, inactivation of the ATM gene by deletion and/or mutation, and isochromosomes 8. For extensive study of chromosomal imbalances in T-PLL, we analyzed 22 tumoral DNAs using comparative genomic hybridization (CGH). Abnormal CGH profiles were detected in all cases, demonstrating highly recurrent gains and losses and largely extending the abnormalities previously established. Only a few nonrecurrent abnormalities were observed, in contrast to the genetic instability anticipated from ATM inactivation. Nine recurrent regions of loss were identified at 8p (frequency 86%), 11q (68%), 22q11 (45%), 13q (41%), 6q (36%), 9p (27%), 12p (23%), 11p11-p14 (23%), and 17p (23%), as well as four regions of gain at 8q (82%), 14q32 (50%), 22q21-qter (41%), and 6p (23%). Several recurrent chromosomal abnormalities were simultaneously present in each case (mean, 5.7; up to 10), none being mutually exclusive of another. Fluorescence in situ hybridization analysis confirmed and extended 22q11 and 13q losses, giving final frequencies of 55% and 45%, respectively. Analysis of one case over a 7-year period confirmed the overall genetic stability of T-PLL and showed that tumor progression was associated with the onset of a few chromosomal abnormalities. This study establishes a complex pattern of highly recurrent chromosomal abnormalities in T-PLL, including some, such as chromosome 13 deletion, commonly found in other lymphoid malignancies.
Assuntos
Deleção Cromossômica , Amplificação de Genes/genética , Leucemia Prolinfocítica de Células T/genética , Leucemia Prolinfocítica/genética , Aberrações Cromossômicas/genética , Transtornos Cromossômicos , Feminino , Humanos , Hibridização in Situ Fluorescente/métodos , Interfase/genética , Masculino , Hibridização de Ácido NucleicoRESUMO
B cell chronic lymphocytic leukaemia (B-CLL) is characterised by defective apoptosis that cannot be explained solely on the basis of the known chromosomal abnormalities. We and other have now reported that the leukemic cells spontaneously display the inducible isoform of nitric oxide synthase, iNOS. Inhibition of the iNOS pathway leads to increased apoptosis of the tumoral cells in vitro, indicating that the endogenous release of NO contributes to their resistance to the normal apoptotic process. The factors that induce the expression of iNOS in vivo in the leukemic cells are not yet identified. Yet, as interaction of B-CLL leukemic cells with bone marrow stromal cells promotes their survival, the involvement of adhesion molecules and integrins may be suspected. The engagement of CD23 stimulates iNOS activation in the tumoral cells, suggesting that in vivo interaction of CD23 with one of its recognised ligands may contribute to iNOS induction. A role for CD40-CD40 ligand interaction may also be hypothesised. The mechanisms involved in the anti-apoptotic role of NO are not fully understood, but may implicate the inhibition of caspase activity, hence the impairment of the Fas pathway. In addition, the mitochondrial membrane potential disruption appears to be a NO-sensitive step in the apoptosis cascade. The presence of a NOS displaying anti-apoptotic properties has now been recognised in different cell types, including various leukaemia. A better knowledge of the mechanisms governing the ultimate fate of NO, anti- versus pro-apoptotic would allow the development of new therapeutic approaches for the treatment of these diseases.
Assuntos
Apoptose/efeitos dos fármacos , Leucemia Linfocítica Crônica de Células B/enzimologia , Apoptose/genética , Humanos , Leucemia Linfocítica Crônica de Células B/etiologia , Leucemia Linfocítica Crônica de Células B/patologia , Óxido Nítrico/farmacologia , Óxido Nítrico/fisiologia , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase/farmacologia , Óxido Nítrico Sintase Tipo IIRESUMO
Mutations of Fas or Fas ligand genes result in the autoimmune lymphoproliferative syndrome (ALPS) in humans. We report here a diffuse large B-cell non-Hodgkin's lymphoma occurring in a man with ALPS. Fas-mediated lymphocyte apoptosis was defective in vitro, owing to a mutation within the death domain of the Fas molecule. High-dose methotrexate and doxorubicin-based chemotherapy led to complete remission of lymphoma.
Assuntos
Doenças Autoimunes/complicações , Linfoma de Células B/complicações , Transtornos Linfoproliferativos/complicações , Receptores do Fator de Necrose Tumoral , Adulto , Antígenos CD20/análise , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose , Doenças Autoimunes/tratamento farmacológico , Doenças Autoimunes/imunologia , Axila , Biomarcadores/análise , Medula Óssea/imunologia , Humanos , Imuno-Histoquímica , Imunossupressores/uso terapêutico , Linfonodos/imunologia , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/imunologia , Transtornos Linfoproliferativos/tratamento farmacológico , Transtornos Linfoproliferativos/imunologia , Masculino , Metotrexato/uso terapêutico , Mutagênese Insercional , Neuropeptídeos/genética , Reação em Cadeia da Polimerase , Linfócitos T/efeitos dos fármacos , Linfócitos T/patologia , Receptor fas/farmacologiaRESUMO
INTRODUCTION: Primary effusion lymphoma is a rare type of B-cell lymphoproliferative disorder which is mainly observed in patients with HIV infection. Lymphomatous cells bridge features of immunoblastic and anaplastic cells with a non-B non-T phenotype and are characterized by the presence of the human herpesvirus 8 genome. We report on the retrospective analysis of 12 cases. PATIENTS AND METHODS: : Twelve HIV-infected patients with serous effusions containing large HHV8(+) lymphomatous cells were extensively evaluated to disclose associated visceral involvement. Clonality was assessed by IgH gene rearrangement PCR analysis (n = 11) or Southern blot (n = 1). EBV and HHV8 DNA sequences were detected by PCR analysis. Cytogenetics studies were performed in seven cases using RHG-banding. RESULTS: Extraserous localizations of lymphoma were present in six cases (50%): mediastinal (n = 2), mesenteric (n = 2), pancreatic (n = 1), and bone marrow involvement (n = 1). A monoclonal rearrangement of IgH genes was demonstrated in six cases, an oligoclonal pattern in one, whereas no clonality could be detected in five. High HHV8 copy numbers were demonstrated in all effusion fluids, with EBV-co-infection in all cases but one. Cytogenetic analysis displayed a complex karyotype in all cases without recurrent abnormalities. Eight patients have died. Three patients are in complete remission at 28, 53 and 55 months after high-dose chemotherapy (n = 1), cidofovir and alpha-interferon combination therapy (n = 1), and antiretroviral therapy alone (n = 1). CONCLUSION: The clinical and molecular pattern, as well as the response to therapy suggest that primary effusion lymphoma represents an heterogenous type of virus-induced B-cell lymphoproliferative disorder, sharing pathophysiological features with that induced by the Epstein-Barr virus and occurring in immunocompromised patients.
Assuntos
Infecções por Herpesviridae/virologia , Herpesvirus Humano 8/isolamento & purificação , Linfoma Relacionado a AIDS/virologia , Linfoma de Células B/virologia , Linfoma Imunoblástico de Células Grandes/virologia , Organofosfonatos , Adulto , Fármacos Anti-HIV/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antivirais/uso terapêutico , Bleomicina/administração & dosagem , Aberrações Cromossômicas , Cidofovir , Ciclofosfamida/administração & dosagem , Ciclofosfamida/uso terapêutico , Citosina/análogos & derivados , Citosina/uso terapêutico , Doxorrubicina/administração & dosagem , Doxorrubicina/uso terapêutico , Quimioterapia Combinada , Etoposídeo/administração & dosagem , Rearranjo Gênico de Cadeia Pesada de Linfócito B , Infecções por Herpesviridae/tratamento farmacológico , Herpesvirus Humano 8/patogenicidade , Humanos , Imunofenotipagem , Interferon-alfa/uso terapêutico , Cariotipagem , Linfoma Relacionado a AIDS/tratamento farmacológico , Linfoma Relacionado a AIDS/etiologia , Linfoma Relacionado a AIDS/genética , Linfoma Relacionado a AIDS/mortalidade , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/etiologia , Linfoma de Células B/genética , Linfoma de Células B/mortalidade , Linfoma Imunoblástico de Células Grandes/tratamento farmacológico , Linfoma Imunoblástico de Células Grandes/etiologia , Linfoma Imunoblástico de Células Grandes/genética , Linfoma Imunoblástico de Células Grandes/mortalidade , Masculino , Metotrexato/administração & dosagem , Pessoa de Meia-Idade , Compostos Organofosforados/uso terapêutico , Reação em Cadeia da Polimerase , Prednisona/administração & dosagem , Prednisona/uso terapêutico , Prognóstico , Indução de Remissão , Análise de Sobrevida , Vincristina/uso terapêutico , Vindesina/administração & dosagem , Carga ViralRESUMO
Survivin is an inhibitor of apoptosis (programmed cell death) overexpressed in various human cancers, but undetectable in normal differentiated tissues. A potential distribution and prognostic significance of survivin in patients with de novo acute myeloid leukaemia (AML) was investigated. By immunofluorescence of bone marrow specimens and peripheral blood mononuclear cells, survivin was detected in 75 out of 125 interpretable AML cases (60%), with reactivity in 50-90% of AML cells. Survivin expression correlated with a lower white blood cell count (WBC) (P = 0.008 by the Mann-Whitney test) and was associated, in the 55 cases of FAB M0/M1/M2, with leukaemic granulocytic maturation (one out of five M/L0, 11 out of 22 M/L1 and 23 out of 28M/L2; P = 0.007 by the Fisher test). In 69 patients treated with the Acute Leukaemia French Association (ALFA) 9000 protocol, survivin expression was significantly associated with a lower WBC (P = 0.03 by the Mann-Whitney test) and favourable/intermediate cytogenetics (P= 0.03 by the Fisher test). There was no significant difference in complete remission rate or overall survival between survivin-positive and survivin-negative AML patients (P = 0.15 by the log-rank test). However, survivin expression became an independent negative prognostic factor for survival when adjusted with the Cox model for established prognostic factors in AML (cytogenetics, age and WBC) or for the ALFA 9000 treatment arm (RR = 2.8 and P = 0.026, by the likelihood-ratio test). These data suggest that survivin expression may be considered as a new unfavourable prognostic factor of de novo AML and suggest a role for apoptosis inhibition in influencing disease outcome.
Assuntos
Medula Óssea/química , Leucemia Mieloide/metabolismo , Proteínas Associadas aos Microtúbulos , Proteínas/análise , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose , Biomarcadores Tumorais/análise , Intervalo Livre de Doença , Humanos , Proteínas Inibidoras de Apoptose , Leucemia Mieloide/imunologia , Leucemia Mieloide/mortalidade , Contagem de Leucócitos , Pessoa de Meia-Idade , Proteínas de Neoplasias , Prognóstico , Análise de Regressão , Indução de Remissão , Estatísticas não Paramétricas , SurvivinaAssuntos
Leucemia Prolinfocítica/genética , Leucemia de Células T/genética , Mutação , Proteínas Serina-Treonina Quinases/genética , Substituição de Aminoácidos , Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia , Proteínas de Ciclo Celular , Proteínas de Ligação a DNA , Éxons , Mutação da Fase de Leitura , Mutação em Linhagem Germinativa , Humanos , Perda de Heterozigosidade , Deleção de Sequência , Proteínas Supressoras de TumorRESUMO
The expression of nitric oxide synthase (NOS) isoforms was investigated in the established ESKOL hairy cell line and in leukemic cells of patients with hairy cell leukemia (HCL). By reverse transcription-polymerase chain reaction (RT-PCR), these cells were found to spontaneously express inducible NOS (iNOS)-specific mRNA, but not endothelial constitutive NOS (ecNOS) mRNA. The iNOS protein was detected by immunofluorescence in the cytoplasm of permeabilized leukemic cells and ESKOL cells, using different anti-iNOS monoclonal antibodies. A protein of 135 kDa was identified by Western blotting in ESKOL and HCL lysates, confirming the presence of an iNOS in these cells. Cytosolic homogenates displayed NOS catalytic activity, as measured by the conversion of 14C-labelled L-arginine into 14C L-citrulline and by detection in situ using the DAF-2DA (diaminofluorescein diacetate) NO-sensitive fluorescent probe. Ligation of CD23 (low affinity IgE receptor) was found to increase iNOS expression in ESKOL and conversely to decrease the percentage of cells undergoing apoptosis, as measured by the percentage of cells expressing annexin V. These results indicate that, as in chronic B cell lymphocytic leukemia cells (B-CLL) a functional iNOS is expressed constitutively in hairy cells that contributes to protecting these tumoral cells from apoptosis.
Assuntos
Regulação Leucêmica da Expressão Gênica , Proteínas de Neoplasias/biossíntese , Células-Tronco Neoplásicas/enzimologia , Óxido Nítrico Sintase/biossíntese , Amidinas/farmacologia , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacologia , Apoptose , Arginina/metabolismo , Benzilaminas/farmacologia , Western Blotting , Indução Enzimática , Inibidores Enzimáticos/farmacologia , Corantes Fluorescentes , Humanos , Leucemia de Células Pilosas/enzimologia , Leucemia de Células Pilosas/patologia , Microscopia de Fluorescência , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Células-Tronco Neoplásicas/patologia , Óxido Nítrico/fisiologia , Óxido Nítrico Sintase/análise , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase Tipo II , Óxido Nítrico Sintase Tipo III , Nitritos/análise , Receptores de IgE/imunologia , Receptores de IgE/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas/enzimologia , Células Tumorais Cultivadas/patologia , ômega-N-Metilarginina/farmacologiaRESUMO
Perforin is known to display a membranolytic activity on tumor cells. Nevertheless, perforin release during natural killer (NK)-cell activation is not sufficient to induce membrane target-cell damage. On the basis of the ability of perforin to interact with phospholipids containing a choline phosphate headgroup, we identify the platelet-activating factor (PAF) and its membrane receptor as crucial components in tumor cell killing activity of human resting NK cells. We demonstrate for the first time that upon activation, naive NK cells release the choline phosphate-containing lysolipid PAF, which binds to perforin and acts as an agonist on perforin-induced membrane damage. PAF is known to incorporate cell membranes using a specific receptor. Here we show that interferon-gamma (IFN-gamma) secreted from activated NK cells ends in PAF-receptor expression on perforin-sensitive K562 cells but not on perforin-resistant Daudi cells. In order to prove the capacity of PAF to interact simultaneously with its membrane PAF receptor and with perforin, we successfully co-purified the 3 components in the presence of bridging PAF molecules. The functional activity of this complex was further examined. The aim was to determine whether membrane PAF-receptor expression on tumor cells, driven to express this receptor, could render them sensitive to the perforin lytic pathway. The results confirmed that transfection of the PAF-receptor complementary DNA into major histocompatibility complex class I and Fas-receptor negative tumor cells restored susceptibility to naive NK cells and perforin attack. Failure of IFN-gamma to induce membrane PAF receptor constitutes the first described mechanism for tumor cells to resist the perforin lytic pathway.