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1.
Nature ; 506(7489): 451-5, 2014 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-24553141

RESUMO

Members of the nuclear factor-κB (NF-κB) family of transcriptional regulators are central mediators of the cellular inflammatory response. Although constitutive NF-κB signalling is present in most human tumours, mutations in pathway members are rare, complicating efforts to understand and block aberrant NF-κB activity in cancer. Here we show that more than two-thirds of supratentorial ependymomas contain oncogenic fusions between RELA, the principal effector of canonical NF-κB signalling, and an uncharacterized gene, C11orf95. In each case, C11orf95-RELA fusions resulted from chromothripsis involving chromosome 11q13.1. C11orf95-RELA fusion proteins translocated spontaneously to the nucleus to activate NF-κB target genes, and rapidly transformed neural stem cells--the cell of origin of ependymoma--to form these tumours in mice. Our data identify a highly recurrent genetic alteration of RELA in human cancer, and the C11orf95-RELA fusion protein as a potential therapeutic target in supratentorial ependymoma.


Assuntos
Transformação Celular Neoplásica , Ependimoma/genética , Ependimoma/metabolismo , NF-kappa B/metabolismo , Proteínas/metabolismo , Transdução de Sinais , Fator de Transcrição RelA/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Sequência de Bases , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular , Núcleo Celular/metabolismo , Transformação Celular Neoplásica/genética , Cromossomos Humanos Par 11/genética , Ependimoma/patologia , Feminino , Humanos , Camundongos , Modelos Genéticos , Dados de Sequência Molecular , NF-kappa B/genética , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Proteínas/genética , Fator de Transcrição RelA/genética , Fatores de Transcrição , Translocação Genética/genética , Proteínas de Sinalização YAP
2.
N Engl J Med ; 373(24): 2336-2346, 2015 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-26580448

RESUMO

BACKGROUND: The prevalence and spectrum of predisposing mutations among children and adolescents with cancer are largely unknown. Knowledge of such mutations may improve the understanding of tumorigenesis, direct patient care, and enable genetic counseling of patients and families. METHODS: In 1120 patients younger than 20 years of age, we sequenced the whole genomes (in 595 patients), whole exomes (in 456), or both (in 69). We analyzed the DNA sequences of 565 genes, including 60 that have been associated with autosomal dominant cancer-predisposition syndromes, for the presence of germline mutations. The pathogenicity of the mutations was determined by a panel of medical experts with the use of cancer-specific and locus-specific genetic databases, the medical literature, computational predictions, and second hits identified in the tumor genome. The same approach was used to analyze data from 966 persons who did not have known cancer in the 1000 Genomes Project, and a similar approach was used to analyze data from an autism study (from 515 persons with autism and 208 persons without autism). RESULTS: Mutations that were deemed to be pathogenic or probably pathogenic were identified in 95 patients with cancer (8.5%), as compared with 1.1% of the persons in the 1000 Genomes Project and 0.6% of the participants in the autism study. The most commonly mutated genes in the affected patients were TP53 (in 50 patients), APC (in 6), BRCA2 (in 6), NF1 (in 4), PMS2 (in 4), RB1 (in 3), and RUNX1 (in 3). A total of 18 additional patients had protein-truncating mutations in tumor-suppressor genes. Of the 58 patients with a predisposing mutation and available information on family history, 23 (40%) had a family history of cancer. CONCLUSIONS: Germline mutations in cancer-predisposing genes were identified in 8.5% of the children and adolescents with cancer. Family history did not predict the presence of an underlying predisposition syndrome in most patients. (Funded by the American Lebanese Syrian Associated Charities and the National Cancer Institute.).


Assuntos
Genes Neoplásicos , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Neoplasias/genética , Adolescente , Transtorno Autístico/genética , Criança , Feminino , Genes Dominantes , Genoma Humano , Humanos , Masculino , Programa de SEER , Análise de Sequência de DNA/métodos , Adulto Jovem
3.
Nat Methods ; 12(6): 527-30, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25938371

RESUMO

We developed Copy Number Segmentation by Regression Tree in Next Generation Sequencing (CONSERTING), an algorithm for detecting somatic copy-number alteration (CNA) using whole-genome sequencing (WGS) data. CONSERTING performs iterative analysis of segmentation on the basis of changes in read depth and the detection of localized structural variations, with high accuracy and sensitivity. Analysis of 43 cancer genomes from both pediatric and adult patients revealed novel oncogenic CNAs, complex rearrangements and subclonal CNAs missed by alternative approaches.


Assuntos
Variações do Número de Cópias de DNA/genética , DNA/genética , Genômica/métodos , Neoplasias/genética , Software , Adulto , Algoritmos , Criança , Biologia Computacional , Regulação Neoplásica da Expressão Gênica , Marcadores Genéticos , Genoma , Humanos
4.
Nature ; 481(7381): 329-34, 2012 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-22237022

RESUMO

Retinoblastoma is an aggressive childhood cancer of the developing retina that is initiated by the biallelic loss of RB1. Tumours progress very quickly following RB1 inactivation but the underlying mechanism is not known. Here we show that the retinoblastoma genome is stable, but that multiple cancer pathways can be epigenetically deregulated. To identify the mutations that cooperate with RB1 loss, we performed whole-genome sequencing of retinoblastomas. The overall mutational rate was very low; RB1 was the only known cancer gene mutated. We then evaluated the role of RB1 in genome stability and considered non-genetic mechanisms of cancer pathway deregulation. For example, the proto-oncogene SYK is upregulated in retinoblastoma and is required for tumour cell survival. Targeting SYK with a small-molecule inhibitor induced retinoblastoma tumour cell death in vitro and in vivo. Thus, retinoblastomas may develop quickly as a result of the epigenetic deregulation of key cancer pathways as a direct or indirect result of RB1 loss.


Assuntos
Epigênese Genética/genética , Genômica , Terapia de Alvo Molecular , Inibidores de Proteínas Quinases/farmacologia , Retinoblastoma/tratamento farmacológico , Retinoblastoma/genética , Aneuploidia , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Instabilidade Cromossômica/genética , Regulação Neoplásica da Expressão Gênica , Genes do Retinoblastoma/genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Camundongos , Mutação/genética , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/metabolismo , Proto-Oncogene Mas , Retinoblastoma/patologia , Proteína do Retinoblastoma/deficiência , Proteína do Retinoblastoma/genética , Análise de Sequência de DNA , Quinase Syk , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Nature ; 481(7380): 157-63, 2012 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-22237106

RESUMO

Early T-cell precursor acute lymphoblastic leukaemia (ETP ALL) is an aggressive malignancy of unknown genetic basis. We performed whole-genome sequencing of 12 ETP ALL cases and assessed the frequency of the identified somatic mutations in 94 T-cell acute lymphoblastic leukaemia cases. ETP ALL was characterized by activating mutations in genes regulating cytokine receptor and RAS signalling (67% of cases; NRAS, KRAS, FLT3, IL7R, JAK3, JAK1, SH2B3 and BRAF), inactivating lesions disrupting haematopoietic development (58%; GATA3, ETV6, RUNX1, IKZF1 and EP300) and histone-modifying genes (48%; EZH2, EED, SUZ12, SETD2 and EP300). We also identified new targets of recurrent mutation including DNM2, ECT2L and RELN. The mutational spectrum is similar to myeloid tumours, and moreover, the global transcriptional profile of ETP ALL was similar to that of normal and myeloid leukaemia haematopoietic stem cells. These findings suggest that addition of myeloid-directed therapies might improve the poor outcome of ETP ALL.


Assuntos
Predisposição Genética para Doença/genética , Mutação/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Idade de Início , Criança , Variações do Número de Cópias de DNA/genética , Genes ras/genética , Genoma Humano/genética , Genômica , Hematopoese/genética , Histonas/metabolismo , Humanos , Janus Quinases/genética , Janus Quinases/metabolismo , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Dados de Sequência Molecular , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Receptores de Interleucina-7/genética , Proteína Reelina , Análise de Sequência de DNA , Transdução de Sinais/genética , Células-Tronco/metabolismo , Células-Tronco/patologia , Linfócitos T/metabolismo , Linfócitos T/patologia , Translocação Genética/genética
6.
Acta Neuropathol ; 131(2): 299-307, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26744350

RESUMO

Gliomatosis cerebri (GC), a rare and deadly CNS neoplasm characterized by involvement of at least three cerebral lobes, predominantly affects adults. While a few small series have reported its occurrence in children, little is known about the molecular characteristics of pediatric GC. We reviewed clinical, radiological, and histological features of pediatric patients with primary GC treated at our institution over 15 years. Targeted sequencing of mutational hotspots in H3F3A, IDH1/2, and BRAF, and genome-wide analysis of DNA methylation and copy number abnormalities was performed in available tumors. Thirty-two patients [23 (72 %) with type 1 and 9 (28 %) with type 2 GC] were identified. Median age at diagnosis was 10.2 years (range 1.5-19.1). A median of 4 cerebral lobes (range 3-8) was affected at diagnosis. In addition, symmetrical bithalamic involvement was observed in 9 (28 %) patients. Twenty-two patients (69 %) had an anaplastic astrocytoma. Despite aggressive therapy, only two patients younger than 3 years at diagnosis are long-term survivors. Clustering analysis of methylation array data from 18 cases classified tumors as IDH (n = 3, 17 %), G34 (n = 4, 22 %), mesenchymal (n = 3, 17 %), and RTK I 'PDGFRA' (n = 8, 44 %). No tumors were classified as K27 subgroup. PDGFRA was the most commonly amplified oncogene in 4 of 22 tumors (18 %). H3F3A p.G34 occurred in all cases classified as G34. Two of 3 cases in the IDH subgroup had IDH1 p.R132H. No H3F3A p.K27 M, IDH2 p.R172, or BRAF p.V600E mutations were observed. There was a trend towards improved survival in the IDH subgroup (P = 0.056). Patients with bithalamic involvement had worse outcomes (P = 0.019). Despite some overlap, the molecular features of pediatric GC are distinct from its adult counterpart. Like in adults, the similarity of genetic and epigenetic characteristics with other infiltrative high-grade gliomas suggests that pediatric GC does not represent a distinct molecular entity.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Metilação de DNA , Neoplasias Neuroepiteliomatosas/genética , Neoplasias Neuroepiteliomatosas/metabolismo , Adolescente , Encéfalo/metabolismo , Neoplasias Encefálicas/classificação , Neoplasias Encefálicas/terapia , Criança , Pré-Escolar , Análise por Conglomerados , Ilhas de CpG , Feminino , Humanos , Lactente , Masculino , Mutação , Neoplasias Neuroepiteliomatosas/classificação , Neoplasias Neuroepiteliomatosas/terapia , Estudos Retrospectivos , Análise de Sobrevida , Adulto Jovem
7.
Acta Neuropathol ; 131(6): 833-45, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26810070

RESUMO

Low-grade neuroepithelial tumors (LGNTs) are diverse CNS tumors presenting in children and young adults, often with a history of epilepsy. While the genetic profiles of common LGNTs, such as the pilocytic astrocytoma and 'adult-type' diffuse gliomas, are largely established, those of uncommon LGNTs remain to be defined. In this study, we have used massively parallel sequencing and various targeted molecular genetic approaches to study alterations in 91 LGNTs, mostly from children but including young adult patients. These tumors comprise dysembryoplastic neuroepithelial tumors (DNETs; n = 22), diffuse oligodendroglial tumors (d-OTs; n = 20), diffuse astrocytomas (DAs; n = 17), angiocentric gliomas (n = 15), and gangliogliomas (n = 17). Most LGNTs (84 %) analyzed by whole-genome sequencing (WGS) were characterized by a single driver genetic alteration. Alterations of FGFR1 occurred frequently in LGNTs composed of oligodendrocyte-like cells, being present in 82 % of DNETs and 40 % of d-OTs. In contrast, a MYB-QKI fusion characterized almost all angiocentric gliomas (87 %), and MYB fusion genes were the most common genetic alteration in DAs (41 %). A BRAF:p.V600E mutation was present in 35 % of gangliogliomas and 18 % of DAs. Pathogenic alterations in FGFR1/2/3, BRAF, or MYB/MYBL1 occurred in 78 % of the series. Adult-type d-OTs with an IDH1/2 mutation occurred in four adolescents, the youngest aged 15 years at biopsy. Despite a detailed analysis, novel genetic alterations were limited to two fusion genes, EWSR1-PATZ1 and SLMAP-NTRK2, both in gangliogliomas. Alterations in BRAF, FGFR1, or MYB account for most pathogenic alterations in LGNTs, including pilocytic astrocytomas, and alignment of these genetic alterations and cytologic features across LGNTs has diagnostic implications. Additionally, therapeutic options based upon targeting the effects of these alterations are already in clinical trials.


Assuntos
Neoplasias Encefálicas/patologia , Genes myb , Predisposição Genética para Doença , Glioma/genética , Mutação/genética , Proteínas Proto-Oncogênicas B-raf/genética , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Adolescente , Adulto , Astrocitoma/genética , Astrocitoma/patologia , Neoplasias Encefálicas/genética , Criança , Pré-Escolar , Proteínas de Ligação a DNA , Feminino , Ganglioglioma/genética , Ganglioglioma/patologia , Glioma/patologia , Humanos , Lactente , Masculino , Proteínas Nucleares/genética , Proteínas de Transporte Nucleocitoplasmático/genética , Proteínas Proto-Oncogênicas/genética , Proteínas de Ligação a RNA , Transativadores/genética , Fatores de Transcrição , Adulto Jovem
8.
Br J Haematol ; 168(1): 94-101, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25164427

RESUMO

Minimal residual disease (MRD) is a strong prognostic factor in children and adolescents with acute myeloid leukaemia (AML) but nearly one-quarter of patients who achieve MRD-negative status still relapse. The adverse prognostic factors among MRD-negative patients remain unknown. We analysed the AML02 study cohort to identify demographic and genetic prognostic factors. Among the presenting features, certain 11q23 abnormalities, such as t(6;11) and t(10;11), acute megakaryoblastic leukaemia without the t(1;22), and age ≥10 years were associated with inferior outcome in patients who had MRD-negative status after either remission induction I or II. By contrast, those with rearrangement of CBF genes had superior outcome. Our study identifies patient populations for whom close post-remission MRD monitoring to detect and treat emerging relapse and adjustment in treatment intensity might be indicated.


Assuntos
Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Criança , Pré-Escolar , Aberrações Cromossômicas , Humanos , Cariótipo , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/mortalidade , Neoplasia Residual/diagnóstico , Prognóstico , Indução de Remissão , Resultado do Tratamento , Tirosina Quinase 3 Semelhante a fms/genética
9.
Pediatr Blood Cancer ; 62(6): 1081-3, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25598012

RESUMO

Children with diffuse intrinsic pontine glioma (DIPG) have a short onset, rapidly progressive neurologic decline before diagnosis. Therefore, incidental diagnosis of such an aggressive cancer is counterintuitive, yet our experience shows DIPG may occur as part of a spectrum of incidentally diagnosed pediatric brain cancers. Although children with incidentally diagnosed DIPG may experience a longer survival, it remains a potentially deadly cancer despite treatment with radiotherapy. Histologic confirmation is warranted when feasible in such patients to confirm diagnosis. Moreover, recent advances in genome-wide analyses may suggest incidentally diagnosed DIPGs are biologically distinct from the majority of these cancers.


Assuntos
Neoplasias do Tronco Encefálico/diagnóstico , Glioma/diagnóstico , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino
10.
Cancer ; 120(10): 1514-9, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24501014

RESUMO

BACKGROUND: Breakpoint cluster region-Abelson murine leukemia viral oncogene homolog 1 (BCR-ABL1) tyrosine kinase inhibitors (TKIs) improve the outcome of patients with childhood Philadelphia chromosome (Ph)-positive acute lymphoblastic leukemia (ALL) when they are incorporated into postremission induction chemotherapy. To date, no data are available on the impact of TKIs on minimal residual disease (MRD) at the end of induction therapy among patients who have a poor early response to 2 weeks of induction therapy that does not include TKIs. METHODS: The authors analyzed the early response to TKIs during remission induction in children with Ph-positive ALL who were treated at St. Jude Children's Research Hospital. MRD was measured on days 15 and 42 of induction. TKIs were incorporated into induction therapy on day 22 in the post-TKI era. RESULTS: TKIs produced a marked drop in MRD levels: at the end of remission induction, 9 of 11 patients who received imatinib or dasatinib and conventional induction chemotherapy achieved MRD-negative status compared with only 2 of 16 patients who received chemotherapy alone (P < .001). The 5-year event-free survival rate (± standard deviation) was 68.6% ± 19.2% for the 11 patients who received TKIs versus 31.6% ± 9.9% for the 19 patients who did not (P = .022); notably, 2 of the former group underwent hematopoietic stem cell transplantation versus 15 of the latter group (P = .002). MRD levels and outcomes did not differ significantly among 498 patients with standard-risk/high-risk, Ph-negative ALL who were treated in the pre-TKI or post-TKI eras. CONCLUSIONS: TKIs administered in the early phases of therapy can dramatically reduce MRD and improve the outcome of childhood Ph-positive ALL.


Assuntos
Antineoplásicos/uso terapêutico , Benzamidas/uso terapêutico , Neoplasia Residual/tratamento farmacológico , Cromossomo Filadélfia , Piperazinas/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Tirosina Quinases/antagonistas & inibidores , Pirimidinas/uso terapêutico , Tiazóis/uso terapêutico , Adolescente , Antineoplásicos/administração & dosagem , Benzamidas/administração & dosagem , Criança , Pré-Escolar , Dasatinibe , Esquema de Medicação , Feminino , Citometria de Fluxo , Genes Codificadores dos Receptores de Linfócitos T , Humanos , Mesilato de Imatinib , Quimioterapia de Indução , Lactente , Masculino , Neoplasia Residual/genética , Neoplasia Residual/prevenção & controle , Piperazinas/administração & dosagem , Reação em Cadeia da Polimerase , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Inibidores de Proteínas Quinases/administração & dosagem , Pirimidinas/administração & dosagem , Tiazóis/administração & dosagem , Resultado do Tratamento
11.
Blood ; 119(10): e67-75, 2012 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-22234698

RESUMO

To identify cooperating lesions in core-binding factor acute myeloid leukemia, we performed single-nucleotide polymorphism-array analysis on 300 diagnostic and 41 relapse adult and pediatric leukemia samples. We identified a mean of 1.28 copy number alterations per case at diagnosis in both patient populations. Recurrent minimally deleted regions (MDRs) were identified at 7q36.1 (7.7%), 9q21.32 (5%), 11p13 (2.3%), and 17q11.2 (2%). Approximately one-half of the 7q deletions were detectable only by single-nucleotide polymorphism-array analysis because of their limited size. Sequence analysis of MLL3, contained within the 7q36.1 MDR, in 46 diagnostic samples revealed one truncating mutation in a leukemia lacking a 7q deletion. Recurrent focal gains were identified at 8q24.21 (4.7%) and 11q25 (1.7%), both containing a single noncoding RNA. Recurrent regions of copy-neutral loss-of-heterozygosity were identified at 1p (1%), 4q (0.7%), and 19p (0.7%), with known mutated cancer genes present in the minimally altered region of 1p (NRAS) and 4q (TET2). Analysis of relapse samples identified recurrent MDRs at 3q13.31 (12.2%), 5q (4.9%), and 17p (4.9%), with the 3q13.31 region containing only LSAMP, a putative tumor suppressor. Determining the role of these lesions in leukemogenesis and drug resistance should provide important insights into core-binding factor acute myeloid leukemia.


Assuntos
Aberrações Cromossômicas , Fatores de Ligação ao Core/genética , Perfilação da Expressão Gênica/métodos , Regulação Leucêmica da Expressão Gênica , Leucemia Mieloide/genética , Doença Aguda , Adulto , Criança , Deleção Cromossômica , Variações do Número de Cópias de DNA , Humanos , Leucemia Mieloide/patologia , Perda de Heterozigosidade , Mutação , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas de Fusão Oncogênica/genética , Polimorfismo de Nucleotídeo Único , Recidiva
13.
Nature ; 453(7191): 110-4, 2008 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-18408710

RESUMO

The Philadelphia chromosome, a chromosomal abnormality that encodes BCR-ABL1, is the defining lesion of chronic myelogenous leukaemia (CML) and a subset of acute lymphoblastic leukaemia (ALL). To define oncogenic lesions that cooperate with BCR-ABL1 to induce ALL, we performed a genome-wide analysis of diagnostic leukaemia samples from 304 individuals with ALL, including 43 BCR-ABL1 B-progenitor ALLs and 23 CML cases. IKZF1 (encoding the transcription factor Ikaros) was deleted in 83.7% of BCR-ABL1 ALL, but not in chronic-phase CML. Deletion of IKZF1 was also identified as an acquired lesion at the time of transformation of CML to ALL (lymphoid blast crisis). The IKZF1 deletions resulted in haploinsufficiency, expression of a dominant-negative Ikaros isoform, or the complete loss of Ikaros expression. Sequencing of IKZF1 deletion breakpoints suggested that aberrant RAG-mediated recombination is responsible for the deletions. These findings suggest that genetic lesions resulting in the loss of Ikaros function are an important event in the development of BCR-ABL1 ALL.


Assuntos
Proteínas de Fusão bcr-abl/genética , Deleção de Genes , Fator de Transcrição Ikaros/deficiência , Fator de Transcrição Ikaros/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Adulto , Criança , Humanos , Fator de Transcrição Ikaros/química , Fator de Transcrição Ikaros/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Polimorfismo de Nucleotídeo Único/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Estrutura Terciária de Proteína
14.
Blood ; 117(23): 6267-76, 2011 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-21487112

RESUMO

To identify new markers for minimal residual disease (MRD) detection in acute lymphoblastic leukemia (ALL), we compared genome-wide gene expression of lymphoblasts from 270 patients with newly diagnosed childhood ALL to that of normal CD19⁺CD10⁺ B-cell progenitors (n = 4). Expression of 30 genes differentially expressed by ≥ 3-fold in at least 25% of cases of ALL (or 40% of ALL subtypes) was tested by flow cytometry in 200 B-lineage ALL and 61 nonleukemic BM samples, including samples containing hematogones. Of the 30 markers, 22 (CD44, BCL2, HSPB1, CD73, CD24, CD123, CD72, CD86, CD200, CD79b, CD164, CD304, CD97, CD102, CD99, CD300a, CD130, PBX1, CTNNA1, ITGB7, CD69, CD49f) were differentially expressed in up to 81.4% of ALL cases; expression of some markers was associated with the presence of genetic abnormalities. Results of MRD detection by flow cytometry with these markers correlated well with those of molecular testing (52 follow-up samples from 18 patients); sequential studies during treatment and diagnosis-relapse comparisons documented their stability. When incorporated in 6-marker combinations, the new markers afforded the detection of 1 leukemic cell among 10(5) BM cells. These new markers should allow MRD studies in all B-lineage ALL patients, and substantially improve their sensitivity.


Assuntos
Biomarcadores Tumorais/biossíntese , Citometria de Fluxo/métodos , Regulação Neoplásica da Expressão Gênica , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Adolescente , Criança , Pré-Escolar , Feminino , Estudo de Associação Genômica Ampla , Humanos , Lactente , Masculino , Neoplasia Residual , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Sensibilidade e Especificidade
15.
Nature ; 446(7137): 758-64, 2007 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-17344859

RESUMO

Chromosomal aberrations are a hallmark of acute lymphoblastic leukaemia (ALL) but alone fail to induce leukaemia. To identify cooperating oncogenic lesions, we performed a genome-wide analysis of leukaemic cells from 242 paediatric ALL patients using high-resolution, single-nucleotide polymorphism arrays and genomic DNA sequencing. Our analyses revealed deletion, amplification, point mutation and structural rearrangement in genes encoding principal regulators of B lymphocyte development and differentiation in 40% of B-progenitor ALL cases. The PAX5 gene was the most frequent target of somatic mutation, being altered in 31.7% of cases. The identified PAX5 mutations resulted in reduced levels of PAX5 protein or the generation of hypomorphic alleles. Deletions were also detected in TCF3 (also known as E2A), EBF1, LEF1, IKZF1 (IKAROS) and IKZF3 (AIOLOS). These findings suggest that direct disruption of pathways controlling B-cell development and differentiation contributes to B-progenitor ALL pathogenesis. Moreover, these data demonstrate the power of high-resolution, genome-wide approaches to identify new molecular lesions in cancer.


Assuntos
Genoma Humano/genética , Mutação/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Alelos , Linfócitos B/metabolismo , Linfócitos B/patologia , Criança , Proteínas de Ligação a DNA/genética , Amplificação de Genes/genética , Genômica , Humanos , Dados de Sequência Molecular , Fator de Transcrição PAX5/genética , Mutação Puntual/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Deleção de Sequência/genética , Transativadores/genética , Translocação Genética/genética
16.
N Engl J Med ; 360(5): 470-80, 2009 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-19129520

RESUMO

BACKGROUND: Despite best current therapy, up to 20% of pediatric patients with acute lymphoblastic leukemia (ALL) have a relapse. Recent genomewide analyses have identified a high frequency of DNA copy-number abnormalities in ALL, but the prognostic implications of these abnormalities have not been defined. METHODS: We studied a cohort of 221 children with high-risk B-cell-progenitor ALL with the use of single-nucleotide-polymorphism microarrays, transcriptional profiling, and resequencing of samples obtained at diagnosis. Children with known very-high-risk ALL subtypes (i.e., BCR-ABL1-positive ALL, hypodiploid ALL, and ALL in infants) were excluded from this cohort. A copy-number abnormality was identified as a predictor of poor outcome, and it was then tested in an independent validation cohort of 258 patients with B-cell-progenitor ALL. RESULTS: More than 50 recurring copy-number abnormalities were identified, most commonly involving genes that encode regulators of B-cell development (in 66.8% of patients in the original cohort); PAX5 was involved in 31.7% and IKZF1 in 28.6% of patients. Using copy-number abnormalities, we identified a predictor of poor outcome that was validated in the independent validation cohort. This predictor was strongly associated with alteration of IKZF1, a gene that encodes the lymphoid transcription factor IKAROS. The gene-expression signature of the group of patients with a poor outcome revealed increased expression of hematopoietic stem-cell genes and reduced expression of B-cell-lineage genes, and it was similar to the signature of BCR-ABL1-positive ALL, another high-risk subtype of ALL with a high frequency of IKZF1 deletion. CONCLUSIONS: Genetic alteration of IKZF1 is associated with a very poor outcome in B-cell-progenitor ALL.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Deleção de Genes , Fator de Transcrição Ikaros/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Linfócitos B/metabolismo , Criança , Estudos de Coortes , Análise Mutacional de DNA , Expressão Gênica , Perfilação da Expressão Gênica , Genótipo , Células-Tronco Hematopoéticas/metabolismo , Humanos , Mutação de Sentido Incorreto , Fator de Transcrição PAX5/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamento farmacológico , Prognóstico , Recidiva , Transativadores/genética , Resultado do Tratamento
17.
Cancer Cell ; 1(2): 133-43, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12086872

RESUMO

Treatment of pediatric acute lymphoblastic leukemia (ALL) is based on the concept of tailoring the intensity of therapy to a patient's risk of relapse. To determine whether gene expression profiling could enhance risk assignment, we used oligonucleotide microarrays to analyze the pattern of genes expressed in leukemic blasts from 360 pediatric ALL patients. Distinct expression profiles identified each of the prognostically important leukemia subtypes, including T-ALL, E2A-PBX1, BCR-ABL, TEL-AML1, MLL rearrangement, and hyperdiploid >50 chromosomes. In addition, another ALL subgroup was identified based on its unique expression profile. Examination of the genes comprising the expression signatures provided important insights into the biology of these leukemia subgroups. Further, within some genetic subgroups, expression profiles identified those patients that would eventually fail therapy. Thus, the single platform of expression profiling should enhance the accurate risk stratification of pediatric ALL patients.


Assuntos
Perfilação da Expressão Gênica , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Algoritmos , Criança , Biologia Computacional , Humanos , Imunofenotipagem , Leucemia Mieloide Aguda/classificação , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Leucemia-Linfoma Linfoblástico de Células Precursoras/classificação , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Prognóstico , Recidiva , Fatores de Risco , Falha de Tratamento
18.
Proc Natl Acad Sci U S A ; 106(31): 12944-9, 2009 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-19651601

RESUMO

Pediatric de novo acute myeloid leukemia (AML) is an aggressive malignancy with current therapy resulting in cure rates of only 60%. To better understand the cause of the marked heterogeneity in therapeutic response and to identify new prognostic markers and therapeutic targets a comprehensive list of the genetic mutations that underlie the pathogenesis of AML is needed. To approach this goal, we examined diagnostic leukemic samples from a cohort of 111 children with de novo AML using single-nucleotide-polymorphism microarrays and candidate gene resequencing. Our data demonstrate that, in contrast to pediatric acute lymphoblastic leukemia (ALL), de novo AML is characterized by a very low burden of genomic alterations, with a mean of only 2.38 somatic copy-number alterations per leukemia, and less than 1 nonsynonymous point mutation per leukemia in the 25 genes analyzed. Even more surprising was the observation that 34% of the leukemias lacked any identifiable copy-number alterations, and 28% of the leukemias with recurrent translocations lacked any identifiable sequence or numerical abnormalities. The only exception to the presence of few mutations was acute megakaryocytic leukemias, with the majority of these leukemias being characterized by a high number of copy-number alterations but rare point mutations. Despite the low overall number of lesions across the patient cohort, novel recurring regions of genetic alteration were identified that harbor known, and potential new cancer genes. These data reflect a remarkably low burden of genomic alterations within pediatric de novo AML, which is in stark contrast to most other human malignancies.


Assuntos
Dosagem de Genes , Leucemia Mieloide Aguda/genética , Mutação , Polimorfismo de Nucleotídeo Único , Criança , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Cinesinas/genética , Perda de Heterozigosidade , Masculino , Miosinas/genética , Proteínas Proto-Oncogênicas/genética , RNA Longo não Codificante , Proteína 1 Parceira de Translocação de RUNX1 , Fatores de Transcrição/genética , Translocação Genética
19.
Clin Cancer Res ; 28(12): 2536-2546, 2022 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-35344039

RESUMO

PURPOSE: To evaluate the safety, activity, and emergence of FLT3-kinase domain (KD) mutations with combination therapy of crenolanib and sorafenib in acute myeloid leukemia (AML) with FLT3-internal tandem duplication (ITD). PATIENTS AND METHODS: After in vitro and xenograft efficacy studies using AML cell lines that have FLT3-ITD with or without FLT3-KD mutation, a pilot study was performed with crenolanib (67 mg/m2/dose, three times per day on days 1-28) and two dose levels of sorafenib (150 and 200 mg/m2/day on days 8-28) in 9 pediatric patients with refractory/relapsed FLT3-ITD-positive AML. Pharmacokinetic, pharmacodynamic, and FLT3-KD mutation analysis were done in both preclinical and clinical studies. RESULTS: The combination of crenolanib and sorafenib in preclinical models showed synergy without affecting pharmacokinetics of each agent, inhibited p-STAT5 and p-ERK for up to 8 hours, and led to significantly better leukemia response (P < 0.005) and survival (P < 0.05) compared with single agents. Fewer FLT3-KD mutations emerged with dose-intensive crenolanib (twice daily) and low-intensity sorafenib (three times/week) compared with daily crenolanib or sorafenib (P < 0.05). The crenolanib and sorafenib combination was tolerable without dose-limiting toxicities, and three complete remissions (one with incomplete count recovery) and one partial remission were observed in 8 evaluable patients. Median crenolanib apparent clearance showed a nonsignificant decrease during treatment (45.0, 40.5, and 20.3 L/hour/m2 on days 1, 7, and 14, respectively) without drug-drug interaction. Only 1 patient developed a FLT3-KD mutation (FLT3 F691L). CONCLUSIONS: The combination of crenolanib and sorafenib was tolerable with antileukemic activities and rare emergence of FLT3-TKD mutations, which warrants further investigation.


Assuntos
Antineoplásicos , Benzimidazóis , Leucemia Mieloide Aguda , Piperidinas , Antineoplásicos/uso terapêutico , Benzimidazóis/uso terapêutico , Criança , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Mutação , Compostos de Fenilureia , Projetos Piloto , Piperidinas/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Sorafenibe/uso terapêutico , Tirosina Quinase 3 Semelhante a fms/antagonistas & inibidores
20.
J Mol Diagn ; 24(5): 503-514, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35101595

RESUMO

The Molecular Pathology Section, Cleveland Clinic (Cleveland, OH), has undergone enhancement of its testing portfolio and processes. An Excel 2013- and paper-based data-management system was replaced with a commercially available laboratory information-management system (LIMS) software application, a separate bioinformatics platform, customized test-interpretation applications, a dedicated sample-accessioning service, and a results-releasing software application. The customized LIMS solution manages complex workflows, large-scale data packets, and process automation. A customized approach was required because, in a survey of commercially available off-the-shelf software products, none met the diverse and complex needs of this molecular diagnostics service. The project utilized the expertise of clinical laboratorians, pathologists, genetics counselors, bioinformaticians, and systems analysts in partnering with software-engineering consultants to design and implement a solution. Concurrently, Agile software-building best practices were formulated, which may be emulated for scalable and cost-effective laboratory-authored software.


Assuntos
Patologia Molecular , Software , Biologia Computacional , Humanos , Laboratórios , Fluxo de Trabalho
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