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1.
Blood ; 135(5): 360-370, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31774495

RESUMO

The oncogenic events involved in breast implant-associated anaplastic large cell lymphoma (BI-ALCL) remain elusive. To clarify this point, we have characterized the genomic landscape of 34 BI-ALCLs (15 tumor and 19 in situ subtypes) collected from 54 BI-ALCL patients diagnosed through the French Lymphopath network. Whole-exome sequencing (n = 22, with paired tumor/germline DNA) and/or targeted deep sequencing (n = 24) showed recurrent mutations of epigenetic modifiers in 74% of cases, involving notably KMT2C (26%), KMT2D (9%), CHD2 (15%), and CREBBP (15%). KMT2D and KMT2C mutations correlated with a loss of H3K4 mono- and trimethylation by immunohistochemistry. Twenty cases (59%) showed mutations in ≥1 member of the JAK/STAT pathway, including STAT3 (38%), JAK1 (18%), and STAT5B (3%), and in negative regulators, including SOCS3 (6%), SOCS1 (3%), and PTPN1 (3%). These mutations were more frequent in tumor-type samples than in situ samples (P = .038). All BI-ALCLs expressed pSTAT3, regardless of the mutational status of genes in the JAK/STAT pathway. Mutations in the EOMES gene (12%) involved in lymphocyte development, PI3K-AKT/mTOR (6%), and loss-of-function mutations in TP53 (12%) were also identified. Copy-number aberration (CNA) analysis identified recurrent alterations, including gains on chromosomes 2, 9p, 12p, and 21 and losses on 4q, 8p, 15, 16, and 20. Regions of CNA encompassed genes involved in the JAK/STAT pathway and epigenetic regulators. Our results show that the BI-ALCL genomic landscape is characterized by not only JAK/STAT activating mutations but also loss-of-function alterations of epigenetic modifiers.

2.
Haematologica ; 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31488561

RESUMO

Peripheral T-cell lymphoma comprises a heterogeneous group of mature non-Hodgkin lymphomas. Their diagnosis is challenging, with up to 30% of cases remaining unclassifiable and referred to as "not otherwise specified". We developed a reverse transcriptase-multiplex ligation-dependent probe amplification gene expression profiling assay to differentiate the main T-cell lymphoma entities and to study the heterogeneity of the "not specified" category. The test evaluates the expression of 20 genes, including 17 markers relevant to T-cell immunology and lymphoma biopathology, one EBV-related transcript, and variants of RHOA (G17V) and IDH2 (R172K/T). By unsupervised hierarchical clustering, our assay accurately identified 21/21 ALK-positive anaplastic large cell lymphomas, 16/16 extranodal NK/T-cell lymphomas, 6/6 hepatosplenic T-cell lymphomas, and 13/13 adult T-cell leukemia/lymphomas. ALK-negative anaplastic lymphomas (n=34) segregated into one cytotoxic cluster (n=10) and one non-cytotoxic cluster expressing Th2 markers (n=24) and enriched in DUSP22-rearranged cases. The 63 TFH-derived lymphomas divided in two subgroups according to a predominant TFH (n=50) or an enrichment in Th2 (n=13) signatures. We next developed a support vector machine predictor which attributed a molecular class to 27/77 not specified T-cell lymphomas: 17 TFH, 5 cytotoxic ALK-negative anaplastic, and 5 NK/T-cell lymphomas. Among the remaining cases, we identified two cell-of-origin subgroups corresponding to cytotoxic/Th1 (n=19) and Th2 (n=24) signatures. A reproducibility test on 40 cases yielded a 90% concordance between 3 independent laboratories. This study demonstrates the applicability of a simple gene expression assay for the classification of peripheral T-cell lymphomas. Its applicability to routinely-fixed samples makes it an attractive adjunct in diagnostic practice.

3.
Eur J Haematol ; 103(1): 35-42, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30985955

RESUMO

OBJECTIVE: Angioimmunoblastic T-cell lymphoma (AITL) is frequently associated with autoimmune cytopenia (AIC). Whether such patients have a particular phenotype and require particular management is unclear. METHOD: Angioimmunoblastic T-cell lymphoma patients from the multicentric database of the Lymphoma Study Association presenting with AIC during disease course were included and matched to AITL patients without AIC (1/5 ratio). RESULTS: At diagnosis, AIC patients (n = 28) had more spleen and bone marrow involvement (54% vs 19% and 71% vs 34%, P < 0.001), Epstein-Barr virus replication (89% vs 39%, P < 0.001), gamma globulin titers (median 23 vs 15 g/L, P = 0.002), and proliferating B cells and plasmablasts in biopsies, as compared to control patients (n = 136). The 28 AIC patients had 41 episodes of AIC, diagnosed concomitantly with AITL in 23 (82%) cases. After a median follow-up of 24 months (range 3-155), 10 patients relapsed, all associated with AITL relapse. CONCLUSION: Our results provide new insight into AIC associated with AITL by highlighting the significant interplay between AITL and B-cell activation leading to subsequent autoimmunity.


Assuntos
Doenças Autoimunes/complicações , Linfadenopatia Imunoblástica/diagnóstico , Linfadenopatia Imunoblástica/terapia , Linfoma de Células T/diagnóstico , Linfoma de Células T/terapia , Pancitopenia/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Doenças Autoimunes/diagnóstico , Biópsia , Gerenciamento Clínico , Suscetibilidade a Doenças , Feminino , Humanos , Linfadenopatia Imunoblástica/etiologia , Linfadenopatia Imunoblástica/mortalidade , Imunoglobulinas Intravenosas/uso terapêutico , Linfoma de Células T/etiologia , Linfoma de Células T/mortalidade , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Pancitopenia/diagnóstico , Fenótipo , Estudos Retrospectivos , Avaliação de Sintomas , Resultado do Tratamento
6.
J Mol Diagn ; 20(5): 677-685, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29981867

RESUMO

Angioimmunoblastic T-cell lymphoma (AITL) is a peripheral T-cell lymphoma associated with chemoresistance and a poor prognosis. Various nonsynonymous mutations in the R172 residue of IDH2 are present in 20% to 30% of AITL patients. In addition to their diagnostic value, these mutations are potentially targetable, especially by isocitrate dehydrogenase (IDH) 2 inhibitor, and therefore their identification in a routine setting is clinically relevant. However, in AITL, the neoplastic cells may be scarce, making the identification of molecular anomalies difficult. We evaluated the diagnostic value of different methods to detect IDH2 mutations in formalin-fixed, paraffin-embedded tumor samples. Immunohistochemistry with an anti-IDH2 R172K antibody, Sanger sequencing, high-resolution melting PCR, allele-specific real-time quantitative PCR, and next-generation sequencing (NGS) were applied to biopsy specimens from 42 AITL patients. We demonstrate that the IDH2 R172K antibody is specific to this amino acid substitution and highly sensitive for the detection of the IDH2R172K variant, the most frequent substitution in this disease. In our study, NGS and allele-specific real-time quantitative PCR displayed a good sensitivity, detecting 96% and 92% of IDH2 mutations, respectively, in contrast to Sanger sequencing and high-resolution melting PCR, which showed a significantly lower detection rate (58% and 42%, respectively). These results suggest that a combination of immunohistochemistry and AS-PCR or NGS should be considered for the identification of IDH2 mutations in AITL in a routine setting.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , Linfadenopatia Imunoblástica/genética , Linfadenopatia Imunoblástica/patologia , Linfoma de Células T/genética , Linfoma de Células T/patologia , Mutação/genética , Substituição de Aminoácidos/genética , Sequência de Bases , Códon/genética , Análise Mutacional de DNA , Humanos , Imuno-Histoquímica , Isocitrato Desidrogenase/genética , Sensibilidade e Especificidade
9.
Haematologica ; 102(4): e148-e151, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28082343
10.
Cancer Discov ; 7(4): 369-379, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28122867

RESUMO

Hepatosplenic T-cell lymphoma (HSTL) is a rare and lethal lymphoma; the genetic drivers of this disease are unknown. Through whole-exome sequencing of 68 HSTLs, we define recurrently mutated driver genes and copy-number alterations in the disease. Chromatin-modifying genes, including SETD2, INO80, and ARID1B, were commonly mutated in HSTL, affecting 62% of cases. HSTLs manifest frequent mutations in STAT5B (31%), STAT3 (9%), and PIK3CD (9%), for which there currently exist potential targeted therapies. In addition, we noted less frequent events in EZH2, KRAS, and TP53SETD2 was the most frequently silenced gene in HSTL. We experimentally demonstrated that SETD2 acts as a tumor suppressor gene. In addition, we found that mutations in STAT5B and PIK3CD activate critical signaling pathways important to cell survival in HSTL. Our work thus defines the genetic landscape of HSTL and implicates gene mutations linked to HSTL pathogenesis and potential treatment targets.Significance: We report the first systematic application of whole-exome sequencing to define the genetic basis of HSTL, a rare but lethal disease. Our work defines SETD2 as a tumor suppressor gene in HSTL and implicates genes including INO80 and PIK3CD in the disease. Cancer Discov; 7(4); 369-79. ©2017 AACR.See related commentary by Yoshida and Weinstock, p. 352This article is highlighted in the In This Issue feature, p. 339.


Assuntos
DNA Helicases/genética , Histona-Lisina N-Metiltransferase/genética , Neoplasias Hepáticas/genética , Linfoma de Células T/genética , Neoplasias Esplênicas/genética , Proteína Supressora de Tumor p53/genética , Adolescente , Adulto , Idoso , Sequência de Bases , Criança , Pré-Escolar , Proteínas de Ligação a DNA , Proteína Potenciadora do Homólogo 2 de Zeste , Exoma/genética , Feminino , Humanos , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/patologia , Linfoma de Células T/complicações , Linfoma de Células T/patologia , Masculino , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas p21(ras) , Neoplasias Esplênicas/complicações , Neoplasias Esplênicas/patologia , Fatores de Transcrição , Proteínas Supressoras de Tumor/genética , Adulto Jovem
11.
Proc Natl Acad Sci U S A ; 113(52): 15084-15089, 2016 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-27956631

RESUMO

Oncogenic isocitrate dehydrogenase (IDH)1 and IDH2 mutations at three hotspot arginine residues cause an enzymatic gain of function that leads to the production and accumulation of the metabolite 2-hydroxyglutarate (2HG), which contributes to the development of a number of malignancies. In the hematopoietic system, mutations in IDH1 at arginine (R) 132 and in IDH2 at R140 and R172 are commonly observed in acute myeloid leukemia, and elevated 2HG is observed in cells and serum. However, in angioimmunoblastic T-cell lymphoma (AITL), mutations are almost exclusively restricted to IDH2 R172, and levels of 2HG have not been comprehensively measured. In this study, we investigate the expression pattern of mutant IDH2 in the AITL tumor microenvironment and measure levels of 2HG in tissue and serum of AITL patients. We find that mutant IDH2 expression is restricted to the malignant T-cell component of AITL, and that 2HG is elevated in tumor tissue and serum of patients. We also investigate the differences between the three hotspot mutation sites in IDH1 and IDH2 using conditional knock-in mouse models. These studies show that in the lymphoid system, mutations in IDH2 at R172 produce high levels of 2HG compared with mutations at the other two sites and that lymphoid development is impaired in these animals. These data provide evidence that IDH2 R172 mutations may be the only variants present in AITL because of their capacity to produce significant amounts of the oncometabolite 2HG in the cell of origin of this disease.


Assuntos
Glutaratos/metabolismo , Isocitrato Desidrogenase/genética , Linfoma de Células T/imunologia , Animais , Biomarcadores Tumorais , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica , Genótipo , Humanos , Isocitrato Desidrogenase/metabolismo , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Linfócitos/metabolismo , Linfoma de Células T/metabolismo , Camundongos , Camundongos Knockout , Mutação
12.
Blood ; 128(11): 1490-502, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27369867

RESUMO

Angioimmunoblastic T-cell lymphoma (AITL) and other lymphomas derived from follicular T-helper cells (TFH) represent a large proportion of peripheral T-cell lymphomas (PTCLs) with poorly understood pathogenesis and unfavorable treatment results. We investigated a series of 85 patients with AITL (n = 72) or other TFH-derived PTCL (n = 13) by targeted deep sequencing of a gene panel enriched in T-cell receptor (TCR) signaling elements. RHOA mutations were identified in 51 of 85 cases (60%) consisting of the highly recurrent dominant negative G17V variant in most cases and a novel K18N in 3 cases, the latter showing activating properties in in vitro assays. Moreover, half of the patients carried virtually mutually exclusive mutations in other TCR-related genes, most frequently in PLCG1 (14.1%), CD28 (9.4%, exclusively in AITL), PI3K elements (7%), CTNNB1 (6%), and GTF2I (6%). Using in vitro assays in transfected cells, we demonstrated that 9 of 10 PLCG1 and 3 of 3 CARD11 variants induced MALT1 protease activity and increased transcription from NFAT or NF-κB response element reporters, respectively. Collectively, the vast majority of variants in TCR-related genes could be classified as gain-of-function. Accordingly, the samples with mutations in TCR-related genes other than RHOA had transcriptomic profiles enriched in signatures reflecting higher T-cell activation. Although no correlation with presenting clinical features nor significant impact on survival was observed, the presence of TCR-related mutations correlated with early disease progression. Thus, targeting of TCR-related events may hold promise for the treatment of TFH-derived lymphomas.


Assuntos
Genes Codificadores dos Receptores de Linfócitos T/genética , Linfadenopatia Imunoblástica/genética , Linfoma Folicular/genética , Linfoma de Células T Periférico/genética , Mutação/genética , Transdução de Sinais , Linfócitos T Auxiliares-Indutores/imunologia , Proteína rhoA de Ligação ao GTP/genética , Biomarcadores Tumorais/genética , Estudos de Coortes , Seguimentos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Linfadenopatia Imunoblástica/imunologia , Linfadenopatia Imunoblástica/patologia , Linfoma Folicular/imunologia , Linfoma Folicular/patologia , Linfoma de Células T Periférico/imunologia , Linfoma de Células T Periférico/patologia , Estadiamento de Neoplasias , Prognóstico
14.
Blood ; 120(19): 3997-4005, 2012 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-22990019

RESUMO

Peripheral T-cell lymphoma (PTCL) is a rare, heterogeneous type of non-Hodgkin lymphoma (NHL) that, in general, is associated with a poor clinical outcome. Therefore, a current major challenge is the discovery of new prognostic tools for this disease. In the present study, a cohort of 122 patients with PTCL was collected from a multicentric T-cell lymphoma consortium (TENOMIC). We analyzed the expression of 80 small nucleolar RNAs (snoRNAs) using high-throughput quantitative PCR. We demonstrate that snoRNA expression analysis may be useful in both the diagnosis of some subtypes of PTCL and the prognostication of both PTCL-not otherwise specified (PTCL-NOS; n = 26) and angio-immunoblastic T-cell lymphoma (AITL; n = 46) patients treated with chemotherapy. Like miRNAs, snoRNAs are globally down-regulated in tumor cells compared with their normal counterparts. In the present study, the snoRNA signature was robust enough to differentiate anaplastic large cell lymphoma (n = 32) from other PTCLs. For PTCL-NOS and AITL, we obtained 2 distinct prognostic signatures with a reduced set of 3 genes. Of particular interest was the prognostic value of HBII-239 snoRNA, which was significantly over-expressed in cases of AITL and PTCL-NOS that had favorable outcomes. Our results suggest that snoRNA expression profiles may have a diagnostic and prognostic significance for PTCL, offering new tools for patient care and follow-up.


Assuntos
Perfilação da Expressão Gênica , Linfoma de Células T Periférico/diagnóstico , Linfoma de Células T Periférico/genética , RNA Nucleolar Pequeno/genética , Idoso , Idoso de 80 Anos ou mais , Ciclo Celular/genética , Proliferação de Células , Análise por Conglomerados , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Linfoma de Células T Periférico/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico
15.
Hum Gene Ther ; 13(12): 1461-70, 2002 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-12215267

RESUMO

Cyr61 is a secreted, cysteine-rich heparin-binding protein that is associated with extracellular matrix and cell surface, and has been demonstrated to be proangiogenic in vitro. In the present study we evaluated the angiogenic effect of human Cyr61 in an adenoviral context in the rabbit ischemic hindlimb model. For this purpose, three randomized groups of New Zealand White rabbits received intramuscular injections of 5 x 10(8) infectious units of an adenovirus carrying either the Cyr61 gene (Ad-Cyr61), the vascular endothelial growth factor gene (Ad-VEGF(165)) used as the angiogenic gene of reference, or no transgene (Ad-Null), 10 days after femoral artery excision in one limb. Perfusion of the ischemic limb was evaluated before adenoviral treatment (day 10) and 30 days postinjection (day 40). Angiographic, hemodynamic, and histologic parameters indicated that animals in the Ad-Cyr61 group had significantly better perfusion than in the Ad-Null group. Interestingly, this improvement exceeded that achieved with Ad-VEGF(165). In conclusion, Cyr61 gene transfer appears potent in stimulating limb revascularization, thereby promoting great improvement in tissue perfusion in the ischemic limb. These findings indicate that Cyr61 could be a promising therapeutic candidate for treating severe peripheral ischemic diseases.


Assuntos
Terapia Genética , Proteínas Imediatamente Precoces/genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Isquemia/terapia , Neovascularização Fisiológica/genética , Adenoviridae , Animais , Proteína Rica em Cisteína 61 , Fatores de Crescimento Endotelial/genética , Vetores Genéticos/administração & dosagem , Membro Posterior/irrigação sanguínea , Humanos , Técnicas In Vitro , Linfocinas/genética , Músculo Esquelético/patologia , Coelhos , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
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