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1.
Nat Commun ; 10(1): 3615, 2019 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-31399598

RESUMO

Genome-wide association studies have provided evidence for inherited genetic predisposition to chronic lymphocytic leukemia (CLL). To gain insight into the mechanisms underlying CLL risk we analyze chromatin accessibility, active regulatory elements marked by H3K27ac, and DNA methylation at 42 risk loci in up to 486 primary CLLs. We identify that risk loci are significantly enriched for active chromatin in CLL with evidence of being CLL-specific or differentially regulated in normal B-cell development. We then use in situ promoter capture Hi-C, in conjunction with gene expression data to reveal likely target genes of the risk loci. Candidate target genes are enriched for pathways related to B-cell development such as MYC and BCL2 signalling. At 14 loci the analysis highlights 63 variants as the probable functional basis of CLL risk. By integrating genetic and epigenetic information our analysis reveals novel insights into the relationship between inherited predisposition and the regulatory chromatin landscape of CLL.


Assuntos
Epigênese Genética/genética , Epigênese Genética/fisiologia , Epigenômica , Predisposição Genética para Doença/genética , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/metabolismo , Linfócitos B/metabolismo , Sequência de Bases , Cromatina/metabolismo , Metilação de DNA , Regulação Leucêmica da Expressão Gênica , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Fatores de Transcrição
2.
Blood ; 133(9): 940-951, 2019 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-30538135

RESUMO

Mantle cell lymphoma (MCL) is characterized by the t(11;14)(q13;q32) translocation resulting in overexpression of cyclin D1. However, a small subset of cyclin D1- MCL has been recognized, and approximately one-half of them harbor CCND2 translocations while the primary event in cyclin D1-/D2- MCL remains elusive. To identify other potential mechanisms driving MCL pathogenesis, we investigated 56 cyclin D1-/SOX11+ MCL by fluorescence in situ hybridization (FISH), whole-genome/exome sequencing, and gene-expression and copy-number arrays. FISH with break-apart probes identified CCND2 rearrangements in 39 cases (70%) but not CCND3 rearrangements. We analyzed 3 of these negative cases by whole-genome/exome sequencing and identified IGK (n = 2) and IGL (n = 1) enhancer hijackings near CCND3 that were associated with cyclin D3 overexpression. By specific FISH probes, including the IGK enhancer region, we detected 10 additional cryptic IGK juxtapositions to CCND3 (6 cases) and CCND2 (4 cases) in MCL that overexpressed, respectively, these cyclins. A minor subset of 4 cyclin D1- MCL cases lacked cyclin D rearrangements and showed upregulation of CCNE1 and CCNE2. These cases had blastoid morphology, high genomic complexity, and CDKN2A and RB1 deletions. Both genomic and gene-expression profiles of cyclin D1- MCL cases were indistinguishable from cyclin D1+ MCL. In conclusion, virtually all cyclin D1- MCLs carry CCND2/CCND3 rearrangements with immunoglobulin genes, including a novel IGK/L enhancer hijacking mechanism. A subset of cyclin D1-/D2-/D3- MCL with aggressive features has cyclin E dysregulation. Specific FISH probes may allow the molecular identification and diagnosis of cyclin D1- MCL.


Assuntos
Ciclina D2/genética , Ciclina D3/genética , Elementos Facilitadores Genéticos , Rearranjo Gênico , Cadeias Leves de Imunoglobulina/genética , Linfoma de Célula do Manto/genética , Idoso , Ciclina D1/genética , Ciclina D1/metabolismo , Feminino , Humanos , Linfoma de Célula do Manto/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Transcrição SOXC/genética , Translocação Genética
5.
Cell Rep ; 16(8): 2061-2067, 2016 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-27524613

RESUMO

Chronic lymphocytic leukemia (CLL) is an adult B cell malignancy. Genome-wide association studies show that variation at 15q15.1 influences CLL risk. We deciphered the causal variant at 15q15.1 and the mechanism by which it influences tumorigenesis. We imputed all possible genotypes across the locus and then mapped highly associated SNPs to areas of chromatin accessibility, evolutionary conservation, and transcription factor binding. SNP rs539846 C>A, the most highly associated variant (p = 1.42 × 10(-13), odds ratio = 1.35), localizes to a super-enhancer defined by extensive histone H3 lysine 27 acetylation in intron 3 of B cell lymphoma 2 (BCL2)-modifying factor (BMF). The rs539846-A risk allele alters a conserved RELA-binding motif, disrupts RELA binding, and is associated with decreased BMF expression in CLL. These findings are consistent with rs539846 influencing CLL susceptibility through differential RELA binding, with direct modulation of BMF expression impacting on anti-apoptotic BCL2, a hallmark of oncogenic dependency in CLL.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Elementos Facilitadores Genéticos , Predisposição Genética para Doença , Leucemia Linfocítica Crônica de Células B/genética , Polimorfismo de Nucleotídeo Único , Proteínas Proto-Oncogênicas c-bcl-2/genética , Fator de Transcrição RelA/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Alelos , Linfócitos B/metabolismo , Linfócitos B/patologia , Sítios de Ligação , Linhagem Celular Tumoral , Cromatina/química , Cromatina/metabolismo , Mapeamento Cromossômico , Cromossomos Humanos Par 15 , Loci Gênicos , Estudo de Associação Genômica Ampla , Histonas/genética , Histonas/metabolismo , Humanos , Leucemia Linfocítica Crônica de Células B/metabolismo , Leucemia Linfocítica Crônica de Células B/patologia , Razão de Chances , Ligação Proteica , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Risco , Fator de Transcrição RelA/metabolismo
6.
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
7.
EMBO J ; 34(14): 1875-88, 2015 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-25991604

RESUMO

MT1-MMP (MMP14) is a collagenolytic enzyme located at the cell surface and implicated in extracellular matrix (ECM) remodeling. Mmp14(-/-) mice present dwarfism, bone abnormalities, and premature death. We demonstrate herein that the loss of MT1-MMP also causes cardiac defects and severe metabolic changes, and alters the cytoskeleton and the nuclear lamina structure. Moreover, the absence of MT1-MMP induces a senescent phenotype characterized by up-regulation of p16(INK4a) and p21(CIP1/WAF) (1), increased activity of senescence-associated ß-galactosidase, generation of a senescence-associated secretory phenotype, and somatotroph axis alterations. Consistent with the role of retinoic acid signaling in nuclear lamina stabilization, treatment of Mmp14(-/-) mice with all-trans retinoic acid reversed the nuclear lamina alterations, partially rescued the cell senescence phenotypes, ameliorated the pathological defects in bone, skin, and heart, and extended their life span. These results demonstrate that nuclear architecture and cell senescence can be modulated by a membrane protease, in a process involving the ECM as a key regulator of nuclear stiffness under cell stress conditions.


Assuntos
Senescência Celular/genética , Metaloproteinase 14 da Matriz/metabolismo , Tretinoína/farmacologia , Tecido Adiposo/metabolismo , Tecido Adiposo/patologia , Animais , Glicemia/análise , Senescência Celular/efeitos dos fármacos , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Células HEK293 , Humanos , Hipoglicemia/genética , Hipoglicemia/metabolismo , Longevidade/efeitos dos fármacos , Metaloproteinase 14 da Matriz/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Membrana Nuclear/genética , Membrana Nuclear/ultraestrutura , Tretinoína/metabolismo
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