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1.
Oncogene ; 36(29): 4224-4232, 2017 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-28368397

RESUMO

Diffuse large B-cell lymphoma (DLBCL) has been categorized into two molecular subtypes that have prognostic significance, namely germinal center B-cell like (GCB) and activated B-cell like (ABC). Although ABC-DLBCL has been associated with NF-κB activation, the relationships between activation of specific NF-κB signals and DLBCL phenotype remain unclear. Application of novel gene expression classifiers identified two new DLBCL categories characterized by selective p100 (NF-κB2) and p105 (NF-κB1) signaling. Interestingly, our molecular studies showed that p105 signaling is predominantly associated with GCB subtype and histone mutations. Conversely, most tumors with p100 signaling displayed ABC phenotype and harbored ABC-associated mutations in genes such as MYD88 and PIM1. In vitro, MYD88 L265P mutation promoted p100 signaling through TAK1/IKKα and GSK3/Fbxw7a pathways, suggesting a novel role for this protein as an upstream regulator of p100. p100 signaling was engaged during activation of normal B cells, suggesting p100's role in ABC phenotype development. Additionally, silencing p100 in ABC-DLBCL cells resulted in a GCB-like phenotype, with suppression of Blimp, IRF4 and XBP1 and upregulation of BCL6, whereas introduction of p52 or p100 into GC cells resulted in differentiation toward an ABC-like phenotype. Together, these findings identify specific roles for p100 and p105 signaling in defining DLBCL molecular subtypes and posit MYD88/p100 signaling as a regulator for B-cell activation.


Assuntos
Linfoma Difuso de Grandes Células B/metabolismo , Subunidade p50 de NF-kappa B/metabolismo , Subunidade p52 de NF-kappa B/metabolismo , Linfócitos B/imunologia , Humanos , Ativação Linfocitária , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/imunologia , Linfoma Difuso de Grandes Células B/patologia , Subunidade p50 de NF-kappa B/genética , Subunidade p50 de NF-kappa B/imunologia , Subunidade p52 de NF-kappa B/genética , Subunidade p52 de NF-kappa B/imunologia , Fenótipo , Transdução de Sinais
3.
Leukemia ; 29(7): 1587-99, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25676418

RESUMO

The pathogenesis of Chlamydophila psittaci-negative ocular adnexal extranodal marginal zone lymphomas (OAEMZLs) is poorly understood. OAEMZLs are monoclonal tumors expressing a biased repertoire of mutated surface immunoglobulins. Antigenic activation of the B-cell receptor (BCR) may have a role in the pathogenesis of these lymphomas. We have analyzed the reactivity of recombinant OAEMZL immunoglobulins. OAEMZL antibodies reacted with self-human antigens, as demonstrated by enzyme-linked immunosorbent assays, HEp-2 immunofluorescence and human protein microarrays. All the analyzed recombinant antibodies (rAbs) exhibited polyreactivity by comprehensive protein array antibody reactivity and some rAbs also demonstrated rheumatoid factor activity. The identity of several reactive antigens was confirmed by microcapillary reverse-phase high-performance liquid chromatography nano-electrospray tandem mass spectrometry. The tested rAbs frequently reacted with shared intracellular and extracellular self-antigens (for example, galectin-3). Furthermore, these self-antigens induced BCR signaling in B cells expressing cognate surface immunoglobulins derived from OAEMZLs. These findings indicate that interactions between self-antigens and cognate OAEMZL tumor-derived BCRs are functional, inducing intracellular signaling. Overall, our findings suggest that self-antigen-induced BCR stimulation may be implicated in the pathogenesis of C. psittaci-negative OAEMZLs.


Assuntos
Chlamydophila psittaci , Neoplasias Oculares/imunologia , Linfoma de Zona Marginal Tipo Células B/imunologia , Receptores de Antígenos de Linfócitos B/imunologia , Receptores de Antígenos de Linfócitos B/metabolismo , Autoantígenos/imunologia , Linfócitos B/imunologia , Western Blotting , Cromatografia Líquida de Alta Pressão , Ensaio de Imunoadsorção Enzimática , Neoplasias Oculares/metabolismo , Neoplasias Oculares/patologia , Imunofluorescência , Humanos , Técnicas Imunoenzimáticas , Imunoprecipitação , Linfoma de Zona Marginal Tipo Células B/metabolismo , Linfoma de Zona Marginal Tipo Células B/patologia , Análise Serial de Proteínas , Psitacose/microbiologia , Proteínas Recombinantes/imunologia , Espectrometria de Massas por Ionização por Electrospray , Células Tumorais Cultivadas
4.
Ann Oncol ; 23(3): 736-742, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21602260

RESUMO

BACKGROUND: A recent study demonstrated that an increased number of CD68+ macrophages were correlated with primary treatment failure, shortened progression-free survival (PFS) and disease-specific survival (DSS) in patients with classical Hodgkin's lymphoma (cHL). PATIENTS AND METHODS: The aim of the present study was to verify the relationship between the number of CD68+ and CD163+ macrophages with clinical outcomes in a cohort of 265 well-characterized patients with cHL treated uniformly with the standard doxorubicin, bleomycin, vinblastine and dacarbazine chemotherapy regimen. Two pairs of hematopathologists carried out independent pathological evaluations of tissue microarray slides. RESULTS: There were no associations between clinical characteristics and the expression of CD68 or CD163. However, higher levels of CD68 and CD163 expression were correlated with the presence of Epstein-Barr virus-positive Hodgkin tumor cells (P = 0.01 and 0.037, respectively). The expression of CD68 or CD163 was not associated with either the PFS or the DSS. CONCLUSION: CD68 and CD163 expression require further evaluation before their use can be recommended for prognostic stratification of patients with cHL.


Assuntos
Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Doença de Hodgkin/patologia , Macrófagos/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Intervalo Livre de Doença , Infecções por Vírus Epstein-Barr/complicações , Feminino , Doença de Hodgkin/mortalidade , Doença de Hodgkin/virologia , Humanos , Imuno-Histoquímica , Hibridização In Situ , Estimativa de Kaplan-Meier , Macrófagos/metabolismo , Masculino , Pessoa de Meia-Idade , Prognóstico , Receptores de Superfície Celular/metabolismo , Análise Serial de Tecidos , Resultado do Tratamento , Adulto Jovem
5.
Leukemia ; 26(4): 814-21, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22024723

RESUMO

Evidence from certain geographical areas links lymphomas of the ocular adnexa marginal zone B-cell lymphomas (OAMZL) with Chlamydophila psittaci (Cp) infection, suggesting that lymphoma development is dependent upon chronic stimulation by persistent infections. Notwithstanding that, the actual immunopathogenetical mechanisms have not yet been elucidated. As in other B-cell lymphomas, insight into this issue, especially with regard to potential selecting ligands, could be provided by analysis of the immunoglobulin (IG) receptors of the malignant clones. To this end, we studied the molecular features of IGs in 44 patients with OAMZL (40% Cp-positive), identifying features suggestive of a pathogenic mechanism of autoreactivity. Herein, we show that lymphoma cells express a distinctive IG repertoire, with electropositive antigen (Ag)-binding sites, reminiscent of autoantibodies (auto-Abs) recognizing DNA. Additionally, five (11%) cases of OAMZL expressed IGs homologous with autoreactive Abs or IGs of patients with chronic lymphocytic leukemia, a disease known for the expression of autoreactive IGs by neoplastic cells. In contrast, no similarity with known anti-Chlamydophila Abs was found. Taken together, these results strongly indicate that OAMZL may originate from B cells selected for their capability to bind Ags and, in particular, auto-Ags. In OAMZL associated with Cp infection, the pathogen likely acts indirectly on the malignant B cells, promoting the development of an inflammatory milieu, where auto-Ags could be exposed and presented, driving proliferation and expansion of self-reactive B cells.


Assuntos
Autoantígenos/imunologia , Neoplasias Oculares/imunologia , Genes de Imunoglobulinas , Linfoma de Zona Marginal Tipo Células B/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise por Conglomerados , Regiões Determinantes de Complementaridade , Neoplasias Oculares/etiologia , Feminino , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Região Variável de Imunoglobulina/genética , Ativação Linfocitária , Linfoma de Zona Marginal Tipo Células B/etiologia , Masculino , Pessoa de Meia-Idade , Psitacose/complicações
6.
Ann Oncol ; 20(2): 309-18, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18842613

RESUMO

BACKGROUND: Positron emission tomography (PET) is a powerful predictor of relapse and survival in non-Hodgkin's lymphomas (NHLs) based on studies carried out in the prerituximab era. Little is known about the predictive power of PET in rituximab-treated patients. PATIENTS AND METHODS: Patients with aggressive B-cell NHL with baseline and follow-up PET studies were included. Clinical characteristics, PET and computed tomography scans, biopsy results, and outcomes were reviewed. PET was defined as positive if higher than mediastinal or background activity was observed. RESULTS: In all, 51 patients (diffuse large B cell-38; mantle cell lymphoma-13) treated with rituximab-containing regimens were included. For 13 of 40 patients (32.5%), mid-therapy PET studies were positive and 9 of 48 patients (18.7%) had positive posttherapy PET. The positive predictive value (PPV), negative predictive value (NPV), sensitivity (Se), and specificity (Sp) of the mid-therapy PET for predicting relapse were 33% [95% confidence interval (CI) 19% to 49%], 68% (95% CI 51% to 81%), 33% (95% CI 6% to 76%), and 68% (95% CI 49% to 82%), respectively. For posttherapy PET, the relapse PPV, NPV, Se and Sp were 19% (95% CI 9% to 33%), 81% (95% CI 67% to 91%), 13% (95% CI 0.6% to 53%), and 80%(95% CI 64% to 90%), respectively. CONCLUSIONS: Compared with previous reports in prerituximab era, addition of rituximab resulted in reduced PPV and sensitivity of mid- and posttherapy PET in patients with aggressive B-cell NHL.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Linfoma não Hodgkin/terapia , Tomografia por Emissão de Pósitrons/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Murinos , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Ciclofosfamida/administração & dosagem , Intervalo Livre de Doença , Doxorrubicina/administração & dosagem , Reações Falso-Positivas , Feminino , Fluordesoxiglucose F18 , Humanos , Linfoma não Hodgkin/diagnóstico por imagem , Linfoma não Hodgkin/patologia , Masculino , Pessoa de Meia-Idade , Prednisona/administração & dosagem , Recidiva , Estudos Retrospectivos , Rituximab , Sensibilidade e Especificidade , Análise de Sobrevida , Vincristina/administração & dosagem , Adulto Jovem
8.
Cell Death Differ ; 12(4): 358-68, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15592436

RESUMO

The p53 pathway is a central apoptotic regulator. Deregulation of the Rb/E2F pathway occurs in a majority of tumors, resulting in both unrestrained proliferation and enhanced apoptosis sensitivity via p53-dependent and independent mechanisms. However, the mechanisms coupling the p53 and Rb/E2F pathways remain incompletely understood. We report that ASPP2/53BP2L, a p53/p73-binding protein that promotes p53/p73-dependent apoptosis, is an E2F target gene. The ASPP2/53BP2L promoter was identified and ectopic expression of transcription-competent E2F-1 (E2F-2 and E2F-3) stimulated an ASPP2/53BP2L promoter-luciferase reporter. Mutational analysis of the ASPP2/53BP2L promoter identified E2F-binding sites that cooperate for E2F-1 induction and basal repression of ASPP2/53BP2L. Moreover, endogenous ASPP2/53BP2L levels increased after E2F-1 expression, and E2F-1 bound the endogenous ASPP2/53BP2L promoter after chromatin immunoprecipitation. Typical for an E2F target, ASPP2/53BP2L expression was maximal in early S-phase. Thus, ASPP2/53BP2L is downstream of E2F, suggesting that it functions as a common link between the p53/p73 and Rb/E2F apoptotic pathways.


Assuntos
Apoptose/fisiologia , Proteínas de Transporte/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição/metabolismo , Apoptose/genética , Proteínas Reguladoras de Apoptose , Sequência de Bases , Proteínas de Transporte/genética , Fatores de Transcrição E2F , Fator de Transcrição E2F1 , Fator de Transcrição E2F2 , Fator de Transcrição E2F3 , Regulação da Expressão Gênica/fisiologia , Genes Supressores de Tumor , Humanos , Dados de Sequência Molecular , Proteínas Nucleares/metabolismo , Regiões Promotoras Genéticas , Fase S/fisiologia , Proteína Tumoral p73 , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor
9.
Leukemia ; 18(11): 1775-9, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15385936

RESUMO

Activation-induced cytidine deaminase (AID), highly expressed in germinal center (GC)-lymphocytes, is involved in somatic hypermutation (SHM). We examined AID expression in diffuse large B-cell lymphomas (DLBCL) of germinal center B-cell (GCB)-like and activated B-cell (ABC)-like subtypes. These two types of DLBCL are characterized by high and low expression of GC-specific genes, respectively. AID expression was detected in both GCB- and ABC-like DLBCL, thus demonstrating a dissociation between AID expression and that of other GC genes. We also tested for the presence of intraclonal heterogeneity in immunoglobulin and BCL6 genes in those same tumors and in follicle center lymphomas (FCL) that transformed to DLBCL. The level of AID expression did not correlate with the presence of intraclonal sequence heterogeneity in either IgV(H) or BCL6. Our findings suggest that lymphomas maintain some but not all of the gene expression signatures of their normal B-cell counterparts. The fact that AID expression can be elevated without intraclonal sequence heterogeneity raises the possibility that other factors are required for SHM in these tumors. We found decreased levels of AID expression in DLBCL that evolved from FCL and which had acquired new mutations in their BCL6 genes. This dissociation suggests that AID expression and SHM may occur at the time prior to the clinical detection of transformed lymphoma.


Assuntos
Citosina Desaminase/metabolismo , Linfoma de Células B/enzimologia , Linfoma Difuso de Grandes Células B/enzimologia , Hipermutação Somática de Imunoglobulina/genética , Citidina Desaminase , Citosina Desaminase/genética , Proteínas de Ligação a DNA/genética , Centro Germinativo/enzimologia , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Região Variável de Imunoglobulina/genética , Leucemia Linfocítica Crônica de Células B/enzimologia , Leucemia Linfocítica Crônica de Células B/genética , Linfoma de Células B/genética , Linfoma Folicular/enzimologia , Linfoma Folicular/genética , Linfoma Difuso de Grandes Células B/genética , Proteínas Proto-Oncogênicas c-bcl-6 , Células Tumorais Cultivadas
10.
Leukemia ; 17(7): 1390-7, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12835729

RESUMO

The BCL6 gene, which functions as a transcription repressor, is the target of multiple chromosomal translocations in non-Hodgkin's lymphomas (NHL). These translocations occur in the nontranslated region of the BCL6 gene, juxtaposing regulatory sequences of the diverse partner genes to the open reading frame of the BCL6 gene and thus are thought to deregulate BCL6 gene expression. The levels of expression of the BCL6 gene and protein have been demonstrated to predict the clinical outcome of diffuse large B-cell lymphomas. By contrast, the prognostic significance of BCL6 gene translocations is unclear. In this study we have sought an explanation for this apparent discrepancy. We examined tumors with a variety of different BCL6 translocations and therefore with a variety of potentially substituted promoters. We found no increase in total BCL6 mRNA levels in the NHL specimens harboring BCL6 gene translocation. Indeed, some of these tumors expressed relatively low quantities of the BCL6 mRNA. We also sought to determine whether BCL6 transcription occurs from the rearranged or from the normal untranslocated allele in these tumors. We demonstrate that lymphoma cell lines and majority of NHL tumor specimens expressed BCL6 mRNA predominantly from the rearranged allele that may come under the control of various partner gene promoters. However, few NHL tumors with BCL6 gene translocations expressed BCL6 mRNA equally from the rearranged and the nonrearranged alleles. Neither the nature of the substituted promoters nor the presence of activating mutations in the BCL6 regulatory sequences correlated with the allelic expression of the BCL6 gene in these tumors.


Assuntos
Cromossomos Humanos Par 3 , Proteínas de Ligação a DNA/genética , Regulação Neoplásica da Expressão Gênica , Linfoma de Células B/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Repressoras/genética , Fatores de Transcrição/genética , Translocação Genética , Alelos , Proteínas de Ligação a DNA/biossíntese , Rearranjo Gênico , Humanos , Mutação , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas/biossíntese , Proteínas Proto-Oncogênicas c-bcl-6 , RNA Mensageiro/análise , Proteínas Repressoras/biossíntese , Fatores de Transcrição/biossíntese , Células Tumorais Cultivadas
11.
Leukemia ; 17(4): 789-95, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12682639

RESUMO

Real-time quantitative reverse transcription polymerase chain reaction (RT-PCR) is a powerful method for measurement of gene expression for diagnostic and prognostic studies of non-Hodgkin's lymphomas (NHL). In order for this technique to gain wide applicability, it is critically important to establish a uniform method for normalization of RNA input. In this study, we have determined the best method to quantify the RNA/cDNA input per reaction and searched for the most useful endogenous control genes for normalization of the measurements, based on their abundance and lowest variability between different types of lymphoid cells. To accomplish these aims, we have analyzed the RNA expression of 11 potential endogenous control genes (glyceraldehyde-3-phosphate dehydrogenase, beta-actin, peptidylprolyl isomerase A, beta 2 microglobulin, protein kinase cGMP-dependent, type I, hypoxanthine phosphoribosyltransferase 1, TATA box binding protein, transferrin receptor, large ribosomal protein, beta-glucoronidase and 18S ribosomal RNA). In all, 12 different B- and T-cell lymphoma/leukemia cell lines, 80 B- and T-cell NHL specimens, and resting and activated normal B and T lymphocytes were screened. Normalization of the nucleic acid input by spectrophotometric OD(260) measurement of RNA proved more reliable than spectrophotometric or fluorometric measurements of cDNA or than electrophoretic estimation of the ribosomal and mRNA fractions. The protein kinase cGMP-dependent, type I (PRKG1) and the TBP genes were expressed at common abundance and exhibited the lowest variability among the cell specimens. We suggest that for further lymphoma studies based on the real-time RT-PCR quantification of gene expression, that RNA input in each reaction be equalized between the specimens by spectrophotometric OD(260) measurements. The expression of the gene of interest in different samples should be normalized by concomitant measurement of the PRKG1 and/or the TBP gene products.


Assuntos
Perfilação da Expressão Gênica/métodos , Leucemia de Células B/genética , Leucemia de Células T/genética , Linfoma não Hodgkin/genética , RNA Mensageiro/análise , RNA Neoplásico/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Biópsia , Sistemas Computacionais , Regulação Neoplásica da Expressão Gênica , Humanos , Leucemia de Células B/patologia , Leucemia de Células T/patologia , Linfócitos/química , Linfoma não Hodgkin/patologia , Proteínas de Neoplasias/análise , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA Neoplásico/biossíntese , RNA Neoplásico/genética , Reprodutibilidade dos Testes , Células Tumorais Cultivadas/química
12.
Leukemia ; 16(9): 1857-62, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12200704

RESUMO

Follicle center lymphoma (FCL) is an indolent low-grade B cell non-Hodgkin's lymphoma (NHL) that frequently transforms to aggressive diffuse large B cell lymphoma (DLBCL). Histological transformation of FCL is commonly associated with accumulation of secondary genetic alterations. The BCL-6 gene is commonly implicated in the pathogenesis of DLBCL and its expression may be altered by clonal rearrangements and somatic point mutations in its 5' non-translated regulatory region. Recently, somatic mutations of the BCL-6 gene were associated with the transformation process. Here, we examined BCL-6 mRNA expression and BCL-6 mutations in paired biopsies from the same patients obtained at the time of FCL diagnosis and after transformation. BCL-6 mRNA expression markedly increased upon transformation (1.9- to 4.8-fold) in three cases, remained unchanged in one case and decreased compared to the diagnosis FCL specimens in four cases. The three specimens that demonstrated an increase in the BCL-6 mRNA expression upon transformation harbored BCL-6 gene mutations in the 5' region of the first intron that overlapped with the previously reported negative regulatory region of the gene. Accumulation of new mutations in this region was not observed in DLBCL biopsies in which the BCL-6 mRNA expression did not increase. The present study demonstrates that although BCL-6 gene mutations do accumulate during the transformation process and, depending on their location within the first intron, may deregulate BCL-6 mRNA expression, increase in BCL-6 mRNA expression is not uniformly required for transformation from FCL to DLBCL.


Assuntos
Regiões 5' não Traduzidas/genética , Transformação Celular Neoplásica/genética , Proteínas de Ligação a DNA/genética , Linfoma de Células B/genética , Linfoma Folicular/genética , Linfoma Difuso de Grandes Células B/genética , Mutação , Proteínas Proto-Oncogênicas/genética , RNA Mensageiro/metabolismo , RNA Neoplásico/metabolismo , Fatores de Transcrição/genética , Primers do DNA/química , Humanos , Técnicas Imunoenzimáticas , Reação em Cadeia da Polimerase , Proteínas Proto-Oncogênicas c-bcl-6
13.
Drug Discov Today ; 6(20): 1062-1067, 2001 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-11590035

RESUMO

Real-time quantitative PCR is the measurement of a fluorescent signal generated and measured during PCR as a consequence of amplicon synthesis. When used as reverse transcriptase-PCR (RT-PCR), real-time quantitative PCR has proved to be useful in accurately measuring expression levels of specific gene transcripts. When applied to questions of minimal residual disease, the technique has evolved from generically detecting the presence of disease cells in individuals, such as the AML1-ETO fusion transcript, to the identification of a specific gene, such as BCL-6, which is prognostic for determining the therapeutic outcome of patients with diffuse large B-cell lymphoma.

15.
Blood ; 98(4): 945-51, 2001 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-11493437

RESUMO

Diffuse large B-cell lymphoma (DLBCL) is characterized by a marked degree of morphologic and clinical heterogeneity. Establishment of parameters that can predict outcome could help to identify patients who may benefit from risk-adjusted therapies. BCL-6 is a proto-oncogene commonly implicated in DLBCL pathogenesis. A real-time reverse transcription-polymerase chain reaction assay was established for accurate and reproducible determination of BCL-6 mRNA expression. The method was applied to evaluate the prognostic significance of BCL-6 expression in DLBCL. BCL-6 mRNA expression was assessed in tumor specimens obtained at the time of diagnosis from 22 patients with primary DLBCL. All patients were subsequently treated with anthracycline-based chemotherapy regimens. These patients could be divided into 2 DLBCL subgroups, one with high BCL-6 gene expression whose median overall survival (OS) time was 171 months and the other with low BCL-6 gene expression whose median OS was 24 months (P =.007). BCL-6 gene expression also predicted OS in an independent validation set of 39 patients with primary DLBCL (P =.01). BCL-6 protein expression, assessed by immunohistochemistry, also predicted longer OS in patients with DLBCL. BCL-6 gene expression was an independent survival predicting factor in multivariate analysis together with the elements of the International Prognostic Index (IPI) (P =.038). By contrast, the aggregate IPI score did not add further prognostic information to the patients' stratification by BCL-6 gene expression. High BCL-6 mRNA expression should be considered a new favorable prognostic factor in DLBCL and should be used in the stratification and the design of risk-adjusted therapies for patients with DLBCL. (Blood. 2001;98:945-951)


Assuntos
Proteínas de Ligação a DNA/genética , Linfoma de Células B/diagnóstico , Linfoma de Células B/mortalidade , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/mortalidade , Proteínas Proto-Oncogênicas/genética , Fatores de Transcrição/genética , Adolescente , Adulto , Idoso , Biomarcadores/análise , Proteínas de Ligação a DNA/normas , Intervalo Livre de Doença , Expressão Gênica , Centro Germinativo/química , Humanos , Imuno-Histoquímica , Linfoma de Células B/química , Linfoma Difuso de Grandes Células B/química , Métodos , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prognóstico , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas/normas , Proteínas Proto-Oncogênicas c-bcl-6 , Reprodutibilidade dos Testes , Taxa de Sobrevida , Fatores de Transcrição/normas
16.
Leukemia ; 15(9): 1451-7, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11516107

RESUMO

Purified, high-titer adenovirus encoding murine CD154 (Ad-CD154) or human CD154 (Ad-hCD154) was used to infect lymph node cells isolated from patients with follicle center lymphoma. Infection of lymphoma B cells with Ad-CD154 at a multiplicity of infection (MOI) ratio of 100 or higher resulted in high-level transgene expression. Additionally, upon infection of lymphoma B cells, only Ad-CD154 resulted in surface expression of CD154, despite similar, high-level expression of either human or mouse CD154 by HeLa cells infected with Ad-hCD154 or Ad-CD154, respectively. Moreover, infection of lymphoma B cells with Ad-CD154, but not Ad-hCD154 or adenovirus encoding Eschericheria coli beta-galactosidase (Ad-LacZ), induced the neoplastic B cells to express higher levels of immune co-stimulatory molecules that are required for proficient presentation of antigen to T cells. Consistent with this, we found that Ad-CD154 infected lymphoma B cells could stimulate T cells to proliferate or produce interferon-gamma in allogeneic or autologous mixed lymphocyte interactions. We conclude that lymphoma B cells can be infected with Ad-CD154 and that this significantly enhances their recognition by allogeneic or autologous T cells. As such, Ad-CD154-transduced lymphoma B cells may have potential for the active immune therapy of patients with follicle center lymphoma.


Assuntos
Adenoviridae , Ligante de CD40/imunologia , Ativação Linfocitária , Linfoma de Células B/imunologia , Linfócitos T/fisiologia , Animais , Divisão Celular , Células HeLa , Humanos , Linfonodos/patologia , Linfonodos/virologia , Teste de Cultura Mista de Linfócitos , Linfoma de Células B/virologia , Camundongos , Fenótipo
17.
Leuk Lymphoma ; 40(3-4): 365-71, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11426559

RESUMO

Reliable long-term vascular access is essential for the treatment of patients with acute myeloid leukemia (AML). Although peripherally inserted central catheters (PICCs) have been in use for many years, little data exist on their use in patients receiving intensive chemotherapy. We retrospectively reviewed all AML patients who had a PICC inserted between July 95 and May 98. Fifty two PICCs were inserted in 40 patients with AML. Thirty three PICCs were inserted during severe thrombocytopenia (platelets < 50 x 10(9)/L), and 31 during severe neutropenia (neutrophils < 0.5 x 10(9)/L). Mean catheter duration was 82 (median 63, range 3-441) days for a total of 4274 catheter days. A mean of 1.8 chemotherapy courses were administered via each PICC. There were 5 early complications of PICC placement. Other mechanical complications occurred in 14 catheters and phlebitis in 12. Twenty blood stream infections (BSI) occurred in 17 patients. All BSIs occurred during neutropenia. Seventeen PICCs were removed due to the following complications - phlebitis (11), possible catheter related BSI (4), mechanical reasons in 3 (2 with concomitant phlebitis) and persistent fever (1). PICC duration was significantly shorter in these 17 catheters (52.9 v 96.4 days in the other 35, p=0.0289). We conclude that PICCs provide long-term vascular access with an acceptable complication rate in patients with AML. However, a randomised trial is required before PICCs can be considered an alternative to tunneled central venous catheters in these patients.


Assuntos
Cateterismo Venoso Central/efeitos adversos , Cateteres de Demora/normas , Leucemia Mieloide/terapia , Doença Aguda , Adolescente , Adulto , Idoso , Antineoplásicos/administração & dosagem , Infecções Bacterianas/etiologia , Infecções Bacterianas/microbiologia , Cateterismo Venoso Central/métodos , Cateterismo Venoso Central/normas , Falha de Equipamento , Feminino , Febre/etiologia , Humanos , Leucemia Mieloide/complicações , Masculino , Pessoa de Meia-Idade , Neutropenia/terapia , Flebite/etiologia , Estudos Retrospectivos , Sepse/etiologia , Trombocitopenia/terapia
18.
Respiration ; 68(2): 169-77, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11287832

RESUMO

BACKGROUND: Bleomycin (Bleo)-induced lung injury in mice serves as an animal model of pulmonary fibrosis. The pathogenesis of pulmonary fibrosis remains unclear, but it comprises both inflammatory and fibrotic components. The cytokine interferon (IFN)-alpha is produced by macrophages and may modulate both fibrogenesis and the determination of T lymphocyte phenotype in pulmonary fibrosis. OBJECTIVE: To investigate the effect of two preparations of recombinant IFN-alpha (IFN-alphaA/D and IFN-alpha2a) on Bleo-induced lung injury in C57BL/6 mice. METHODS: Mice were treated by a single intratracheal (IT) instillation of 0.06 mg of Bleo in 0.1 ml of saline or saline alone. One of two different IFN-alpha preparations, IFN-alphaA/D or IFN-alpha2a in saline, or saline alone were administered by daily intraperitoneal injections starting 1 day prior to IT instillation. The treatment groups were as follows: IT Bleo and intraperitoneal saline; IT Bleo and intraperitoneal IFN-alpha2a; IT Bleo and intraperitoneal IFN-alphaA/D; IT saline and intraperitoneal IFN-alphaA/D or IFN-alpha2a; IT saline and intraperitoneal saline. The animals were sacrificed 14 days after IT instillation. Lung injury was evaluated by total and differential cell count in bronchoalveolar lavage (BAL) fluid, by a semiquantitative morphological index of lung injury and a quantitative image analysis of cellularity and fibrosis fraction and by biochemical analysis of lung hydroxyproline content. RESULTS: In Bleo-treated mice, IFN-alpha2a treatment caused a significant rise in BAL lymphocytes and in cellularity and fibrosis fractions in lung tissue. In contrast, IFN-alphaA/D treatment had no effect on Bleo-induced lung injury. CONCLUSION: IFN-alpha may enhance Bleo-induced lung injury but this effect varies with different IFN preparations.


Assuntos
Interferon-alfa/administração & dosagem , Fibrose Pulmonar/tratamento farmacológico , Animais , Bleomicina/efeitos adversos , Líquido da Lavagem Broncoalveolar , Modelos Animais de Doenças , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fibrose Pulmonar/patologia , Proteínas Recombinantes
19.
Leuk Lymphoma ; 42(6): 1343-50, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11911418

RESUMO

Follicle center lymphoma (FCL) accounts for approximately 40% of all non-Hodgkin's lymphomas (NHL). The genetic-environmental interactions involved in the etiology and pathogenesis of this disease are unknown. In our previous study a single nucleotide polymorphism (SNP) (397C) in the regulatory untranslated first intron region of the BCL-6 gene was found in four of the eight FCL patients but in none of the 10 healthy controls. To further evaluate the potential association between the 397C allele of the BCL-6 gene and FCL, we performed a case-control study. Genomic DNA was isolated from 85 FCL patients, from 98 control cases without a previous history of malignancy, treated at Stanford University Medical Center for non-malignant disorders and from 90 samples from the DNA Polymorphism Discovery Resource. The 397G and the 397C polymorphic alleles were identified by a PCR-RFLP method. To evaluate the possible effect of this polymorphism on gene expression, BCL-6 mRNA levels in nine FCL tumors with the 397G-G genotype and in nine FCL tumors with the 397G-C genotype were measured by quantitative real-time RT-PCR. The 397C polymorphic allele was found in 32 FCL cases (37.6%), in 20 controls (20.4%) and in 17 (18.9%) samples from the DNA Polymorphism Discovery Resource. The prevalence of the 397G-C and 397C-C genotypes was significantly higher in FCL cases than in control group (p = 0.01). No difference in BCL-6 gene expression was observed between FCL cases with 397G-G and 397G-C genotypes. The present study demonstrates a possible association between the 397C allele of the BCL-6 proto-oncogene and FCL. The similar levels of BCL-6 mRNA expression in 397G-G and in 397G-C FCL cases suggests that any possible oncogenic effect of the polymorphic allele would not simply be related to a direct effect on BCL-6 gene expression and suggests the existence of other FCL susceptibility genes that are in linkage disequilibrium with the 397C allele of the BCL-6 gene.


Assuntos
Proteínas de Ligação a DNA/genética , Linfoma Folicular/genética , Polimorfismo Genético , Proteínas Proto-Oncogênicas/genética , Fatores de Transcrição/genética , Genótipo , Humanos , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-bcl-6 , RNA Mensageiro/análise
20.
Life Sci ; 67(23): 2873-81, 2000 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-11106002

RESUMO

Since transforming growth factor beta (TGF-beta) is presumed to play a role in lung fibrosis, we evaluated the effect of suramin (Sur), a substance with an anti-TGF-beta effect, in vivo on bleomycin (Bleo)-induced pulmonary injury in mice and in vitro on human lung fibroblasts. Four groups of C57BL/6 mice each received one of four treatments: (1) intratracheal (i.t.) instillation of Bleo and intraperitoneal (i.p.) injections of Sur, every other day, starting one day before i.t. instillation of Bleo (Bleo-Sur); (2) i.t. Bleo and i.p. injections of saline (Bleo-Sal); (3) i.t. saline and i.p. Sur (Sal-Sur); and (4) i.t. and i.p. saline (Sal-Sal). Animals were sacrificed 14 days after i.t. treatment. Lung injury was evaluated by analysis of bronchoalveolar lavage (BAL) fluid, histologically by the semiquantitative morphological index, and biochemically by analysis of lung hydroxyproline content. In vitro, Sur did not affect TGF-beta induced increase of alpha1 (I) collagen mRNA in human lung fibroblasts. In vivo treatment of mice with Sur did not affect Bleo-induced lung injury. These results indicate that despite its potential anti TGF-beta and lymphocytotoxic effects, Sur is not a therapeutic candidate drug for rescue of lung fibrosis.


Assuntos
Bleomicina/toxicidade , Pulmão/efeitos dos fármacos , Suramina/farmacologia , Animais , Bleomicina/administração & dosagem , Líquido da Lavagem Broncoalveolar/citologia , Linhagem Celular , Colágeno/genética , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Injeções Intraperitoneais , Instilação de Medicamentos , Luciferases/genética , Pulmão/patologia , Linfócitos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neutrófilos/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/patologia , Suramina/administração & dosagem , Transfecção , Fator de Crescimento Transformador beta/antagonistas & inibidores , Fator de Crescimento Transformador beta/farmacologia
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