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2.
Nature ; 574(7780): 712-716, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31597163

RESUMO

Cancers are caused by genomic alterations known as drivers. Hundreds of drivers in coding genes are known but, to date, only a handful of noncoding drivers have been discovered-despite intensive searching1,2. Attention has recently shifted to the role of altered RNA splicing in cancer; driver mutations that lead to transcriptome-wide aberrant splicing have been identified in multiple types of cancer, although these mutations have only been found in protein-coding splicing factors such as splicing factor 3b subunit 1 (SF3B1)3-6. By contrast, cancer-related alterations in the noncoding component of the spliceosome-a series of small nuclear RNAs (snRNAs)-have barely been studied, owing to the combined challenges of characterizing noncoding cancer drivers and the repetitive nature of snRNA genes1,7,8. Here we report a highly recurrent A>C somatic mutation at the third base of U1 snRNA in several types of tumour. The primary function of U1 snRNA is to recognize the 5' splice site via base-pairing. This mutation changes the preferential A-U base-pairing between U1 snRNA and the 5' splice site to C-G base-pairing, and thus creates novel splice junctions and alters the splicing pattern of multiple genes-including known drivers of cancer. Clinically, the A>C mutation is associated with heavy alcohol use in patients with hepatocellular carcinoma, and with the aggressive subtype of chronic lymphocytic leukaemia with unmutated immunoglobulin heavy-chain variable regions. The mutation in U1 snRNA also independently confers an adverse prognosis to patients with chronic lymphocytic leukaemia. Our study demonstrates a noncoding driver in spliceosomal RNAs, reveals a mechanism of aberrant splicing in cancer and may represent a new target for treatment. Our findings also suggest that driver discovery should be extended to a wider range of genomic regions.

3.
J Clin Invest ; 128(9): 4132-4147, 2018 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-29990311

RESUMO

Cyclin D1 is an oncogene frequently overexpressed in human cancers that has a dual function as cell cycle and transcriptional regulator, although the latter is widely unexplored. Here, we investigated the transcriptional role of cyclin D1 in lymphoid tumor cells with cyclin D1 oncogenic overexpression. Cyclin D1 showed widespread binding to the promoters of most actively transcribed genes, and the promoter occupancy positively correlated with the transcriptional output of targeted genes. Despite this association, the overexpression of cyclin D1 in lymphoid cells led to a global transcriptional downmodulation that was proportional to cyclin D1 levels. This cyclin D1-dependent global transcriptional downregulation was associated with a reduced nascent transcription and an accumulation of promoter-proximal paused RNA polymerase II (Pol II) that colocalized with cyclin D1. Concordantly, cyclin D1 overexpression promoted an increase in the Poll II pausing index. This transcriptional impairment seems to be mediated by the interaction of cyclin D1 with the transcription machinery. In addition, cyclin D1 overexpression sensitized cells to transcription inhibitors, revealing a synthetic lethality interaction that was also observed in primary mantle cell lymphoma cases. This finding of global transcriptional dysregulation expands the known functions of oncogenic cyclin D1 and suggests the therapeutic potential of targeting the transcriptional machinery in cyclin D1-overexpressing tumors.


Assuntos
Ciclina D1/genética , Ciclina D1/metabolismo , Linfoma de Célula do Manto/genética , Linfoma de Célula do Manto/metabolismo , Carcinogênese/genética , Linhagem Celular Tumoral , Cromatina/genética , Cromatina/metabolismo , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Código das Histonas , Humanos , Modelos Biológicos , Regiões Promotoras Genéticas , RNA Polimerase II/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcrição Genética
5.
Nat Med ; 24(6): 868-880, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29785028

RESUMO

Chronic lymphocytic leukemia (CLL) is a frequent hematological neoplasm in which underlying epigenetic alterations are only partially understood. Here, we analyze the reference epigenome of seven primary CLLs and the regulatory chromatin landscape of 107 primary cases in the context of normal B cell differentiation. We identify that the CLL chromatin landscape is largely influenced by distinct dynamics during normal B cell maturation. Beyond this, we define extensive catalogues of regulatory elements de novo reprogrammed in CLL as a whole and in its major clinico-biological subtypes classified by IGHV somatic hypermutation levels. We uncover that IGHV-unmutated CLLs harbor more active and open chromatin than IGHV-mutated cases. Furthermore, we show that de novo active regions in CLL are enriched for NFAT, FOX and TCF/LEF transcription factor family binding sites. Although most genetic alterations are not associated with consistent epigenetic profiles, CLLs with MYD88 mutations and trisomy 12 show distinct chromatin configurations. Furthermore, we observe that non-coding mutations in IGHV-mutated CLLs are enriched in H3K27ac-associated regulatory elements outside accessible chromatin. Overall, this study provides an integrative portrait of the CLL epigenome, identifies extensive networks of altered regulatory elements and sheds light on the relationship between the genetic and epigenetic architecture of the disease.


Assuntos
Cromatina/metabolismo , Epigenômica , Leucemia Linfocítica Crônica de Células B/genética , Linfócitos B/metabolismo , Sequência de Bases , Estudos de Coortes , Humanos
6.
Blood ; 132(4): 413-422, 2018 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-29769262

RESUMO

Mantle cell lymphoma (MCL) is an aggressive B-cell malignancy, but some patients have a very indolent evolution. This heterogeneous course is related, in part, to the different biological characteristics of conventional MCL (cMCL) and the distinct subgroup of leukemic nonnodal MCL (nnMCL). Robust criteria to distinguish these MCL subtypes and additional biological parameters that influence their evolution are not well defined. We describe a novel molecular assay that reliably distinguishes cMCL and nnMCL using blood samples. We trained a 16-gene assay (L-MCL16 assay) on the NanoString platform using 19 purified leukemic samples. The locked assay was applied to an independent cohort of 70 MCL patients with leukemic presentation. The assay assigned 37% of cases to nnMCL and 56% to cMCL. nnMCL and cMCL differed in nodal presentation, lactate dehydrogenase, immunoglobulin heavy chain gene mutational status, management options, genomic complexity, and CDKN2A/ATM deletions, but the proportion with 17p/TP53 aberrations was similar in both subgroups. Sequential samples showed that assay prediction was stable over time. nnMCL had a better overall survival (OS) than cMCL (3-year OS 92% vs 69%; P = .006) from the time of diagnosis and longer time to first treatment. Genomic complexity and TP53/CDKN2A aberrations predicted for shorter OS in the entire series and cMCL, whereas only genomic complexity was associated with shorter time to first treatment and OS in nnMCL. In conclusion, the newly developed assay robustly recognizes the 2 molecular subtypes of MCL in leukemic samples. Its combination with genetic alterations improves the prognostic evaluation and may provide useful biological information for management decisions.


Assuntos
Biomarcadores Tumorais/genética , Leucemia/genética , Leucemia/patologia , Linfoma de Célula do Manto/genética , Linfoma de Célula do Manto/patologia , Mutação , Estudos de Coortes , Feminino , Perfilação da Expressão Gênica , Genômica , Humanos , Leucemia/classificação , Linfoma de Célula do Manto/classificação , Masculino , Prognóstico , Taxa de Sobrevida
7.
Leuk Lymphoma ; 59(10): 2318-2326, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29115891

RESUMO

Small lymphocytic lymphoma (SLL) is considered as the non-leukemic form of presentation of chronic lymphocytic leukemia (CLL). We have compared the features, genomic alterations, and outcome of 890 patients with CLL and SLL. One hundred and thirteen patients presented as SLL and more frequently had unmutated-IGHV, CD38high, ZAP-70high, CD49dhigh, +12, alterations in genes of NOTCH1, cell cycle, RNA metabolism, and NFkB pathways than CLL. During the follow-up, 46% of SLL patients developed CLL. Time to first treatment (TTFT) was shorter in SLL (10-year: 75% vs 62%; p = .006). Binet stage, SLL, and IGHV were independent predictive factors for TTFT. Transformation to diffuse large B-cell lymphoma was higher (10-year: 12% vs 6%; p = .003), and overall survival was shorter in SLL (10-year: 55% vs 66%; p = .004). When A0 CLL patients were excluded, only CD38 and CD49d expression, +12, and 10-year TTFT remained different between the SLL and CLL patients. In summary, SLL showed only minor clinicobiological differences when compared with CLL in similar clinical stages.


Assuntos
Genoma Humano/genética , Leucemia Linfocítica Crônica de Células B/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise Mutacional de DNA , Feminino , Seguimentos , Humanos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/mortalidade , Leucemia Linfocítica Crônica de Células B/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Análise de Sobrevida , Tempo para o Tratamento/estatística & dados numéricos , Adulto Jovem
9.
J Clin Oncol ; 35(15): 1668-1677, 2017 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-28291392

RESUMO

Purpose Mantle cell lymphoma is an aggressive B-cell neoplasm that displays heterogeneous outcomes after treatment. In 2003, the Lymphoma/Leukemia Molecular Profiling Project described a powerful biomarker-the proliferation signature-using gene expression in fresh frozen material. Herein, we describe the training and validation of a new assay that measures the proliferation signature in RNA derived from routinely available formalin-fixed paraffin-embedded (FFPE) biopsies. Methods Forty-seven FFPE biopsies were used to train an assay on the NanoString platform, using microarray gene expression data of matched fresh frozen biopsies as a gold standard. The locked assay was applied to pretreatment FFPE lymph node biopsies from an independent cohort of 110 patients uniformly treated with rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone. Seventeen biopsies were tested across three laboratories to assess assay reproducibility. Results The MCL35 assay, which contained a 17-gene proliferation signature, yielded gene expression of sufficient quality to assign an assay score and risk group in 108 (98%) of 110 archival FFPE biopsies. The MCL35 assay assigned patients to high-risk (26%), standard-risk (29%), and low-risk (45%) groups, with different lengths of overall survival (OS): a median of 1.1, 2.6, and 8.6 years, respectively (log-rank for trend, P < .001). In multivariable analysis, these risk groups and the Mantle Cell Lymphoma International Prognostic Index were independently associated with OS ( P < .001 for both variables). Concordance of risk assignment across the three independent laboratories was 100%. Conclusion The newly developed and validated MCL35 assay for FFPE biopsies uses the proliferation signature to define groups of patients with significantly different OS independent of the Mantle Cell Lymphoma International Prognostic Index. Importantly, the analytic and clinical validity of this assay defines it as a reliable biomarker to support risk-adapted clinical trials.


Assuntos
Biópsia/métodos , Linfoma de Célula do Manto/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Proliferação de Células/fisiologia , Feminino , Formaldeído , Perfilação da Expressão Gênica , Humanos , Linfoma de Célula do Manto/genética , Masculino , Pessoa de Meia-Idade , Inclusão em Parafina , Reprodutibilidade dos Testes , Fixação de Tecidos
10.
Blood ; 127(17): 2122-30, 2016 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-26837699

RESUMO

Genomic studies have revealed the complex clonal heterogeneity of chronic lymphocytic leukemia (CLL). The acquisition and selection of genomic aberrations may be critical to understanding the progression of this disease. In this study, we have extensively characterized the mutational status of TP53, SF3B1, BIRC3, NOTCH1, and ATM in 406 untreated CLL cases by ultra-deep next-generation sequencing, which detected subclonal mutations down to 0.3% allele frequency. Clonal dynamics were examined in longitudinal samples of 48 CLL patients. We identified a high proportion of subclonal mutations, isolated or associated with clonal aberrations. TP53 mutations were present in 10.6% of patients (6.4% clonal, 4.2% subclonal), ATM mutations in 11.1% (7.8% clonal, 1.3% subclonal, 2% germ line mutations considered pathogenic), SF3B1 mutations in 12.6% (7.4% clonal, 5.2% subclonal), NOTCH1 mutations in 21.8% (14.2% clonal, 7.6% subclonal), and BIRC3 mutations in 4.2% (2% clonal, 2.2% subclonal). ATM mutations, clonal SF3B1, and both clonal and subclonal NOTCH1 mutations predicted for shorter time to first treatment irrespective of the immunoglobulin heavy-chain variable-region gene (IGHV) mutational status. Clonal and subclonal TP53 and clonal NOTCH1 mutations predicted for shorter overall survival together with the IGHV mutational status. Clonal evolution in longitudinal samples mainly occurred in cases with mutations in the initial samples and was observed not only after chemotherapy but also in untreated patients. These findings suggest that the characterization of the subclonal architecture and its dynamics in the evolution of the disease may be relevant for the management of CLL patients.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/genética , Genes p53 , Proteínas Inibidoras de Apoptose/genética , Leucemia Linfocítica Crônica de Células B/genética , Proteínas de Neoplasias/genética , Fosfoproteínas/genética , Fatores de Processamento de RNA/genética , Receptor Notch1/genética , Ubiquitina-Proteína Ligases/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteínas Mutadas de Ataxia Telangiectasia/fisiologia , Proteína 3 com Repetições IAP de Baculovírus , Células Clonais , Análise Mutacional de DNA , Progressão da Doença , Evolução Molecular , Feminino , Humanos , Proteínas Inibidoras de Apoptose/fisiologia , Estimativa de Kaplan-Meier , Leucemia Linfocítica Crônica de Células B/terapia , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas de Neoplasias/fisiologia , Células-Tronco Neoplásicas , Fosfoproteínas/fisiologia , Prognóstico , Fatores de Processamento de RNA/fisiologia , Receptor Notch1/fisiologia , Tempo para o Tratamento , Resultado do Tratamento , Proteína Supressora de Tumor p53/fisiologia , Ubiquitina-Proteína Ligases/fisiologia , Adulto Jovem
11.
Oncotarget ; 7(5): 5507-20, 2016 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-26701728

RESUMO

Clinical responses to bendamustine in chronic lymphocytic leukemia (CLL) are highly heterogeneous and no specific markers to predict sensitivity to this drug have been reported. In order to identify biomarkers of response, we analyzed the in vitro activity of bendamustine and the gene expression profile in primary CLL cells. We observed that mRNA expression of CD69 (CD69) and ITGAM (CD11b) constitute the most powerful predictor of response to bendamustine. When we interrogated the predictive value of the corresponding cell surface proteins, the expression of the activation marker CD69 was the most reliable predictor of sensitivity to bendamustine. Importantly, a multivariate analysis revealed that the predictive value of CD69 expression was independent from other clinico-biological CLL features. We also showed that when CLL cells were co-cultured with distinct subtypes of stromal cells, an upregulation of CD69 was accompanied by a reduced sensitivity to bendamustine. In agreement with this, tumor cells derived from lymphoid tumor niches harbored higher CD69 expression and were less sensitive to bendamustine than their peripheral blood counterparts. Furthermore, pretreatment of CD69 high CLL cases with the B-cell receptor (BCR) pathway inhibitors ibrutinib and idelalisib decreased CD69 levels and enhanced bendamustine cytotoxic effect. Collectively, our findings indicate that CD69 could be a predictor of bendamustine response in CLL patients and the combination of clinically-tested BCR signaling inhibitors with bendamustine may represent a promising strategy for bendamustine low responsive CLL cases.


Assuntos
Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Apoptose/efeitos dos fármacos , Cloridrato de Bendamustina/farmacologia , Lectinas Tipo C/metabolismo , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/metabolismo , Purinas/farmacologia , Pirazóis/farmacologia , Pirimidinas/farmacologia , Quinazolinonas/farmacologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD/genética , Antígenos de Diferenciação de Linfócitos T/genética , Antineoplásicos/farmacologia , Antineoplásicos Alquilantes/farmacologia , Proliferação de Células/efeitos dos fármacos , Feminino , Seguimentos , Humanos , Lectinas Tipo C/genética , Leucemia Linfocítica Crônica de Células B/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Transcriptoma , Células Tumorais Cultivadas
12.
Genes Chromosomes Cancer ; 54(11): 668-80, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26305789

RESUMO

Chronic lymphocytic leukemia (CLL) is a common disease with highly variable clinical course. Several recurrent chromosomal alterations are associated with prognosis and may guide risk-adapted therapy. We have developed a targeted genome-wide array to provide a robust tool for ascertaining abnormalities in CLL and to overcome limitations of the 4-marker fluorescence in situ hybridization (FISH). DNA from 180 CLL patients were hybridized to the qChip®Hemo array with a high density of probes covering commonly altered loci in CLL (11q22-q23, 13q14, and 17p13), nine focal regions (2p15-p16.1, 2p24.3, 2q13, 2q36.3-q37.1, 3p21.31, 8q24.21, 9p21.3, 10q24.32, and 18q21.32-q21.33) and two larger regions (6q14.1-q22.31 and 7q31.33-q33). Overall, 86% of the cases presented copy number alterations (CNA) by array. There was a high concordance of array findings with FISH (84% sensitivity, 100% specificity); all discrepancies corresponded to subclonal alterations detected only by FISH. A chromothripsis-like pattern was detected in eight cases. Three showed concomitant shattered 5p with gain of TERT along with isochromosome 17q. Presence of 11q loss was associated with shorter time to first treatment (P = 0.003), whereas 17p loss, increased genomic complexity, and chromothripsis were associated with shorter overall survival (P < 0.001, P = 0.001, and P = 0.02, respectively). In conclusion, we have validated a targeted array for the diagnosis of CLL that accurately detects, in a single experiment, all relevant CNAs, genomic complexity, chromothripsis, copy number neutral loss of heterozygosity, and CNAs not covered by the FISH panel. This test may be used as a practical tool to stratify CLL patients for routine diagnostics or clinical trials.


Assuntos
Aberrações Cromossômicas , Leucemia Linfocítica Crônica de Células B/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Dosagem de Genes , Genoma Humano , Humanos , Leucemia Linfocítica Crônica de Células B/diagnóstico , Masculino , Pessoa de Meia-Idade , Mutação , Análise de Sequência com Séries de Oligonucleotídeos/métodos
13.
Nature ; 526(7574): 519-24, 2015 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-26200345

RESUMO

Chronic lymphocytic leukaemia (CLL) is a frequent disease in which the genetic alterations determining the clinicobiological behaviour are not fully understood. Here we describe a comprehensive evaluation of the genomic landscape of 452 CLL cases and 54 patients with monoclonal B-lymphocytosis, a precursor disorder. We extend the number of CLL driver alterations, including changes in ZNF292, ZMYM3, ARID1A and PTPN11. We also identify novel recurrent mutations in non-coding regions, including the 3' region of NOTCH1, which cause aberrant splicing events, increase NOTCH1 activity and result in a more aggressive disease. In addition, mutations in an enhancer located on chromosome 9p13 result in reduced expression of the B-cell-specific transcription factor PAX5. The accumulative number of driver alterations (0 to ≥4) discriminated between patients with differences in clinical behaviour. This study provides an integrated portrait of the CLL genomic landscape, identifies new recurrent driver mutations of the disease, and suggests clinical interventions that may improve the management of this neoplasia.


Assuntos
Leucemia Linfocítica Crônica de Células B/genética , Mutação/genética , Regiões 3' não Traduzidas/genética , Processamento Alternativo/genética , Linfócitos B/metabolismo , Proteínas de Transporte/genética , Cromossomos Humanos Par 9/genética , Análise Mutacional de DNA , DNA de Neoplasias/genética , Elementos Facilitadores Genéticos/genética , Genômica , Humanos , Leucemia Linfocítica Crônica de Células B/metabolismo , Leucemia Linfocítica Crônica de Células B/patologia , Proteínas do Tecido Nervoso/genética , Proteínas Nucleares/genética , Fator de Transcrição PAX5/biossíntese , Fator de Transcrição PAX5/genética , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Receptor Notch1/genética , Receptor Notch1/metabolismo , Fatores de Transcrição/genética
14.
J Pathol ; 234(3): 423-30, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25141821

RESUMO

Follicular lymphoma (FL) is one of the most common malignant lymphomas. The t(14;18)(q32;q21) translocation is found in about 80% of cases and plays an important role in lymphomagenesis. However, the molecular mechanisms involved in the development and transformation of this lymphoma are not fully understood. Gain-of-function mutations of NOTCH1 or NOTCH2 have recently been reported in several B cell lymphoid neoplasms but the role of these mutations in FL is not known. In this study we investigated the mutational status of these genes in 112 FLs. NOTCH1 and NOTCH2 mutations were identified in five and two cases, respectively (total 7/112, 6.3%). All mutations predicted for truncated protein in the PEST domain and were identical to those identified in other B cell lymphoid neoplasms. NOTCH-mutated FL cases were characterized by lower frequency of t(14;18) (14% versus 69%, p = 0.01), higher incidence of splenic involvement (71% versus 25%, p = 0.02) and female predominance (100% versus 55%, p = 0.04). A diffuse large B cell lymphoma (DLBCL) component was more frequently identified in NOTCH-mutated FL than in wild-type cases (57% versus 18%, p = 0.03). These results indicate that NOTCH mutations are uncommon in FL but may occur in a subset of cases with distinctive, characteristic, clinicopathological features.


Assuntos
Linfoma Folicular/genética , Linfoma Folicular/patologia , Mutação , Receptor Notch1/genética , Receptor Notch2/genética , Adulto , Idoso , Análise Mutacional de DNA , Feminino , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
Haematologica ; 99(10): 1599-604, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24972773

RESUMO

We investigated the clinico-biological features, outcomes, and prognosis of 949 patients with chronic lymphocytic leukemia according to age. No biological differences (cytogenetics by fluorescent in situ hybridization, IGHV, ZAP-70, CD38, NOTCH1, SF3B1) were found across age groups. Elderly patients (>70 years; n=367) presented more frequently with advanced disease (Binet C/Rai III-IV: 10/12% versus 5/5%; P<0.001), were treated less frequently (23.8% versus 41.9% at 3 years; P<0.001) and in most cases did not receive highly effective regimens and thus had a lower overall response rate (49% with 14% having complete responses versus 69% with 31% having complete responses; P<0.001). The elderly patients also had a shorter overall survival (6.6 versus 13.3 years; P<0.001) and higher disease-unrelated mortality (34.9% versus 6.9% at 10 years; P<0.001). However, disease-attributable mortality was not significantly different between younger and older patients. A combination of Binet stage, ZAP-70 level, ß2-microglobulin concentration and comorbidity identified two risk groups (low-risk: 0-1 parameters; high-risk: 2-4 parameters) with different overall survivals (median: 6.8 versus 11.4 years, P<0.001). In patients requiring treatment, comorbidity at treatment (Cumulative Illness Rating Scale-T>4; hazard ratio 2.2, P<0.001) and response (treatment failure versus response: hazard ratio 1.60, P<0.04) were the most important prognostic factors for overall survival. In conclusion, in our series, elderly patients with chronic lymphocytic leukemia did not present with any biological features distinct from those of younger patients, but did have a poorer clinical outcome. This study highlights the importance of comprehensive medical care, achieving response to therapy, and specific management strategies for elderly patients with chronic lymphocytic leukemia.


Assuntos
Leucemia Linfocítica Crônica de Células B/epidemiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Feminino , Seguimentos , Humanos , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/terapia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Avaliação de Resultados da Assistência ao Paciente , Prognóstico , Análise de Sobrevida
17.
Blood ; 123(24): 3790-6, 2014 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-24782504

RESUMO

Mutations in Toll-like receptor (TLR) and myeloid differentiation primary response 88 (MYD88) genes have been found in chronic lymphocytic leukemia (CLL) at low frequency. We analyzed the incidence, clinicobiological characteristics, and outcome of patients with TLR/MYD88 mutations in 587 CLL patients. Twenty-three patients (3.9%) had mutations, 19 in MYD88 (one with concurrent IRAK1 mutation), 2 TLR2 (one with concomitant TLR6 mutation), 1 IRAK1, and 1 TLR5. No mutations were found in IRAK2 and IRAK4. TLR/MYD88-mutated CLL overexpressed genes of the nuclear factor κB pathway. Patients with TLR/MYD88 mutations were significantly younger (83% age ≤50 years) than those with no mutations. TLR/MYD88 mutations were the most frequent in young patients. Patients with mutated TLR/MYD88 CLL had a higher frequency of mutated IGHV and low expression of CD38 and ZAP-70. Overall survival (OS) was better in TLR/MYD88-mutated than unmutated patients in the whole series (10-year OS, 100% vs 62%; P = .002), and in the subset of patients age ≤50 years (100% vs 70%; P = .02). In addition, relative OS of TLR/MYD88-mutated patients was similar to that in the age- and gender-matched population. In summary, TLR/MYD88 mutations identify a population of young CLL patients with favorable outcome.


Assuntos
Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/genética , Mutação , Fator 88 de Diferenciação Mieloide/genética , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Transdução de Sinais/genética , Adulto Jovem
18.
Haematologica ; 99(5): 873-80, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24700492

RESUMO

A proportion of patients with chronic lymphocytic leukemia achieve a minimal residual disease negative status after therapy. We retrospectively evaluated the impact of minimal residual disease on the outcome of 255 consecutive patients receiving any front-line therapy in the context of a detailed prognostic evaluation, including assessment of IGHV, TP53, NOTCH1 and SF3B1 mutations. The median follow-up was 73 months (range, 2-202) from disease evaluation. The median treatment-free survival durations for patients achieving a complete response without or with minimal residual disease, a partial response and no response were 76, 40, 11 and 11 months, respectively (P<0.001). Multivariate analysis revealed that three variables had a significant impact on treatment-free survival: minimal residual disease (P<0.001), IGHV status (P<0.001) and ß2-microglobulin levels (P=0.012). With regards to overall survival, factors predictive of an unfavorable outcome were minimal residual disease positivity (P=0.014), together with advanced age (P<0.001), unmutated IGHV status (P=0.001), TP53 mutations (P<0.001) and elevated levels of ß2-microglobulin (P=0.003). In conclusion, for patients requiring front-line therapy, achievement of minimal residual disease negativity is associated with significantly prolonged treatment-free and overall survival irrespective of other prognostic markers or treatment administered.


Assuntos
Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Neoplasia Residual/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Seguimentos , Humanos , Quimioterapia de Indução , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Mutação , Estadiamento de Neoplasias , Neoplasia Residual/genética , Prognóstico , Resultado do Tratamento
19.
Genome Res ; 24(2): 212-26, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24265505

RESUMO

Chronic lymphocytic leukemia (CLL) has heterogeneous clinical and biological behavior. Whole-genome and -exome sequencing has contributed to the characterization of the mutational spectrum of the disease, but the underlying transcriptional profile is still poorly understood. We have performed deep RNA sequencing in different subpopulations of normal B-lymphocytes and CLL cells from a cohort of 98 patients, and characterized the CLL transcriptional landscape with unprecedented resolution. We detected thousands of transcriptional elements differentially expressed between the CLL and normal B cells, including protein-coding genes, noncoding RNAs, and pseudogenes. Transposable elements are globally derepressed in CLL cells. In addition, two thousand genes-most of which are not differentially expressed-exhibit CLL-specific splicing patterns. Genes involved in metabolic pathways showed higher expression in CLL, while genes related to spliceosome, proteasome, and ribosome were among the most down-regulated in CLL. Clustering of the CLL samples according to RNA-seq derived gene expression levels unveiled two robust molecular subgroups, C1 and C2. C1/C2 subgroups and the mutational status of the immunoglobulin heavy variable (IGHV) region were the only independent variables in predicting time to treatment in a multivariate analysis with main clinico-biological features. This subdivision was validated in an independent cohort of patients monitored through DNA microarrays. Further analysis shows that B-cell receptor (BCR) activation in the microenvironment of the lymph node may be at the origin of the C1/C2 differences.


Assuntos
Linfócitos B , Regulação Neoplásica da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Leucemia Linfocítica Crônica de Células B/genética , Idoso , Sequência de Bases , Feminino , Perfilação da Expressão Gênica , Humanos , Região Variável de Imunoglobulina , Leucemia Linfocítica Crônica de Células B/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Ribossomos/genética , Spliceossomos/genética
20.
Proc Natl Acad Sci U S A ; 110(45): 18250-5, 2013 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-24145436

RESUMO

Mantle cell lymphoma (MCL) is an aggressive tumor, but a subset of patients may follow an indolent clinical course. To understand the mechanisms underlying this biological heterogeneity, we performed whole-genome and/or whole-exome sequencing on 29 MCL cases and their respective matched normal DNA, as well as 6 MCL cell lines. Recurrently mutated genes were investigated by targeted sequencing in an independent cohort of 172 MCL patients. We identified 25 significantly mutated genes, including known drivers such as ataxia-telangectasia mutated (ATM), cyclin D1 (CCND1), and the tumor suppressor TP53; mutated genes encoding the anti-apoptotic protein BIRC3 and Toll-like receptor 2 (TLR2); and the chromatin modifiers WHSC1, MLL2, and MEF2B. We also found NOTCH2 mutations as an alternative phenomenon to NOTCH1 mutations in aggressive tumors with a dismal prognosis. Analysis of two simultaneous or subsequent MCL samples by whole-genome/whole-exome (n = 8) or targeted (n = 19) sequencing revealed subclonal heterogeneity at diagnosis in samples from different topographic sites and modulation of the initial mutational profile at the progression of the disease. Some mutations were predominantly clonal or subclonal, indicating an early or late event in tumor evolution, respectively. Our study identifies molecular mechanisms contributing to MCL pathogenesis and offers potential targets for therapeutic intervention.


Assuntos
Evolução Clonal/genética , Variação Genética , Genoma Humano/genética , Linfoma de Célula do Manto/genética , Mutação/genética , Proteínas Mutadas de Ataxia Telangiectasia/genética , Sequência de Bases , Ciclina D1/genética , Estudo de Associação Genômica Ampla , Genômica/métodos , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Linfoma de Célula do Manto/fisiopatologia , Análise em Microsséries , Dados de Sequência Molecular , Receptor Notch2/genética , Receptor 2 Toll-Like/genética
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