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1.
Ann Oncol ; 29(12): 2363-2370, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30307529

RESUMO

Background: Gene expression profiling (GEP) studies recognized a prognostic role for tumor microenvironment (TME) in diffuse large B-cell lymphoma (DLBCL), but the routinely adoption of prognostic stromal signatures remains limited. Patients and methods: Here, we applied the computational method CIBERSORT to generate a 1028-gene matrix incorporating signatures of 17 immune and stromal cytotypes. Then, we carried out a deconvolution on publicly available GEP data of 482 untreated DLBCLs to reveal associations between clinical outcomes and proportions of putative tumor-infiltrating cell types. Forty-five genes related to peculiar prognostic cytotypes were selected and their expression digitally quantified by NanoString technology on a validation set of 175 formalin-fixed, paraffin-embedded DLBCLs from two randomized trials. Data from an unsupervised clustering analysis were used to build a model of clustering assignment, whose prognostic value was also assessed on an independent cohort of 40 cases. All tissue samples consisted of pretreatment biopsies of advanced-stage DLBCLs treated by comparable R-CHOP/R-CHOP-like regimens. Results: In silico analysis demonstrated that higher proportion of myofibroblasts (MFs), dendritic cells, and CD4+ T cells correlated with better outcomes and the expression of genes in our panel is associated with a risk of overall and progression-free survival. In a multivariate Cox model, the microenvironment genes retained high prognostic performance independently of the cell-of-origin (COO), and integration of the two prognosticators (COO + TME) improved survival prediction in both validation set and independent cohort. Moreover, the major contribution of MF-related genes to the panel and Gene Set Enrichment Analysis suggested a strong influence of extracellular matrix determinants in DLBCL biology. Conclusions: Our study identified new prognostic categories of DLBCL, providing an easy-to-apply gene panel that powerfully predicts patients' survival. Moreover, owing to its relationship with specific stromal and immune components, the panel may acquire a predictive relevance in clinical trials exploring new drugs with known impact on TME.


Assuntos
Linfoma Difuso de Grandes Células B/mortalidade , Transcriptoma/genética , Microambiente Tumoral/genética , Adulto , Idoso , Algoritmos , Biópsia , Análise por Conglomerados , Estudos de Coortes , Biologia Computacional , Conjuntos de Dados como Assunto , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , Masculino , Pessoa de Meia-Idade , Inclusão em Parafina , Valor Preditivo dos Testes , Prognóstico , Intervalo Livre de Progressão , Ensaios Clínicos Controlados Aleatórios como Assunto , Reprodutibilidade dos Testes , Análise de Sobrevida , Adulto Jovem
3.
Cell Death Differ ; 7(2): 177-88, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10713732

RESUMO

Induction of apoptosis seems to be a key function in maintaining normal cell growth by exerting negative controls on cell proliferation and suppressing tumorigenesis. The adenovirus E1A oncogene shows both cell cycle progression and apoptotic functions. To understand the mechanism of E1A-induced apoptosis, the apoptotic function of E1A 13S was investigated in p53-null cells. We show here that E1A is sufficient by itself to induce substantial apoptosis independent of p53 and other adenoviral genes. The apoptotic function of E1A is accompanied by processing of caspase-3 and cleavage of poly(ADP-ribose)-polymerase. Cell death is significantly blocked by the caspase inhibitor zVAD-fmk and when coexpressed with E1B19K, Bcl-2 or the retinoblastoma protein (RB). Analyses of E1A mutants indicated that the apoptotic activity of E1A correlates closely with the ability to bind the key regulators of E2F1-induced apoptosis, p300 and RB. Finally, in vivo relevance of down-modulation of p53-independent apoptosis for efficient transformation is demonstrated.


Assuntos
Proteínas E1A de Adenovirus/genética , Apoptose/genética , Regulação Viral da Expressão Gênica , Proteína Supressora de Tumor p53/genética , Adenoviridae/genética , Animais , Linhagem Celular , Técnicas de Transferência de Genes , Genes Virais
4.
J Virol ; 71(12): 9538-48, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9371617

RESUMO

The transformation-defective Vero cell host range mutant CS-1 of the highly oncogenic adenovirus type 12 (Ad12) (Ad12-CS-1) has a 69-bp deletion in the early region 1A (E1A) gene that removes the carboxy-terminal half of conserved region 2 and the amino-terminal half of the Ad12-specific so-called spacer that seems to play a pivotal role in the oncogenicity of the virus. Despite its deficiency in immortalizing and transforming primary rodent cells, we found that the E1A 13S protein of Ad12-CS-1 retains the ability to bind p105-RB, p107, and p130 in nuclear extract binding assays with glutathione S-transferase-E1A fusion proteins and Western blot analysis. Like wild-type E1A, the mutant protein was able to dissociate E2F from retinoblastoma-related protein-containing complexes, as judged from gel shift experiments with purified 12S and 13S proteins from transfection experiments with an E1A expression vector or from infection with the respective virus. Moreover, in transient expression assays, the 12S and 13S products of wild-type Ad12 and Ad12-CS-1 were shown to transactivate the Ad12 E1A promoter containing E2F-1 and E2F-5-motifs, respectively, in a comparable manner. The same results were obtained from transfection assays with the E2F motif-dependent E2 promoter of adenovirus type 5 or the human dihydrofolate reductase promoter. These data suggest that efficient infection by Ad12 and the correlated virus-induced reprogramming of the infected cells, including the induction of cell cycle-relevant mechanisms (e.g. E2F activation), can be uncoupled from the transformation properties of the virus.


Assuntos
Adenoviridae/metabolismo , Proteínas E1A de Adenovirus/metabolismo , Proteínas de Transporte , Proteínas de Ciclo Celular , Proteínas de Ligação a DNA , Vírus Defeituosos/metabolismo , Proteínas Nucleares/metabolismo , Fosfoproteínas/metabolismo , Regiões Promotoras Genéticas , Proteínas , Proteína do Retinoblastoma/metabolismo , Transativadores , Fatores de Transcrição/metabolismo , Ativação Transcricional , Adenoviridae/genética , Proteínas E1A de Adenovirus/genética , Sequência de Aminoácidos , Transformação Celular Viral , Vírus Defeituosos/genética , Fatores de Transcrição E2F , Fator de Transcrição E2F1 , Fator de Transcrição E2F5 , Humanos , Dados de Sequência Molecular , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteína 1 de Ligação ao Retinoblastoma , Proteína p107 Retinoblastoma-Like , Proteína p130 Retinoblastoma-Like , Deleção de Sequência , Fator de Transcrição DP1 , Células Tumorais Cultivadas
5.
Mol Cell Neurosci ; 18(1): 68-79, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11461154

RESUMO

Neurodegeneration in Huntington's disease (HD) is associated with an elongated glutamine tract in the widely expressed huntingtin protein. Although the pathogenic mechanisms are still unknown, the distinct physical properties of mutant huntingtin in the brain suggest that other factors including huntingtin-interacting proteins might play a specific role. We have previously identified a DNA-binding motif in the proximal E1A promoter of adenovirus serotype 12 as responsible for E1A autoregulation. Here, we identified the p231HBP protein as a DNA-binding factor, the C-terminal portion of which has recently been characterized as the huntingtin-interacting protein HYPB of unknown function. We have determined the full-length cDNA sequence, identified several domains supporting its gene regulatory functions, and mapped the HBP231 gene to chromosome 3p21.2-p21.3. Our results provide an interesting molecular link between huntingtin and a DNA-binding factor, implicating that this interaction might result in the alteration of cellular gene expression involved in HD pathogenesis.


Assuntos
Cromossomos Humanos Par 3 , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Proteínas Nucleares/metabolismo , Proteínas E1A de Adenovirus/genética , Sequência de Aminoácidos , Animais , Mapeamento Cromossômico , DNA Complementar , Expressão Gênica/fisiologia , Células HeLa , Humanos , Proteína Huntingtina , Hibridização in Situ Fluorescente , Dados de Sequência Molecular , Regiões Promotoras Genéticas/fisiologia , Coelhos , Técnicas do Sistema de Duplo-Híbrido
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