RESUMO
Clear cell renal cell carcinoma (ccRCC) is characterized by near-universal loss of the short arm of chromosome 3, deleting several tumor suppressor genes. We analyzed whole genomes from 95 biopsies across 33 patients with clear cell renal cell carcinoma. We find hotspots of point mutations in the 5' UTR of TERT, targeting a MYC-MAX-MAD1 repressor associated with telomere lengthening. The most common structural abnormality generates simultaneous 3p loss and 5q gain (36% patients), typically through chromothripsis. This event occurs in childhood or adolescence, generally as the initiating event that precedes emergence of the tumor's most recent common ancestor by years to decades. Similar genomic changes drive inherited ccRCC. Modeling differences in age incidence between inherited and sporadic cancers suggests that the number of cells with 3p loss capable of initiating sporadic tumors is no more than a few hundred. Early development of ccRCC follows well-defined evolutionary trajectories, offering opportunity for early intervention.
Assuntos
Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Progressão da Doença , Neoplasias Renais/genética , Neoplasias Renais/patologia , Mutação , Regiões 5' não Traduzidas , Adulto , Idoso , Idoso de 80 Anos ou mais , Cromossomos Humanos Par 3 , Cromossomos Humanos Par 5 , Feminino , Dosagem de Genes , Genoma Humano , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Telomerase/genética , Proteína Supressora de Tumor Von Hippel-Lindau/genéticaRESUMO
The lymphocyte genome is prone to many threats, including programmed mutation during differentiation1, antigen-driven proliferation and residency in diverse microenvironments. Here, after developing protocols for expansion of single-cell lymphocyte cultures, we sequenced whole genomes from 717 normal naive and memory B and T cells and haematopoietic stem cells. All lymphocyte subsets carried more point mutations and structural variants than haematopoietic stem cells, with higher burdens in memory cells than in naive cells, and with T cells accumulating mutations at a higher rate throughout life. Off-target effects of immunological diversification accounted for approximately half of the additional differentiation-associated mutations in lymphocytes. Memory B cells acquired, on average, 18 off-target mutations genome-wide for every on-target IGHV mutation during the germinal centre reaction. Structural variation was 16-fold higher in lymphocytes than in stem cells, with around 15% of deletions being attributable to off-target recombinase-activating gene activity. DNA damage from ultraviolet light exposure and other sporadic mutational processes generated hundreds to thousands of mutations in some memory cells. The mutation burden and signatures of normal B cells were broadly similar to those seen in many B-cell cancers, suggesting that malignant transformation of lymphocytes arises from the same mutational processes that are active across normal ontogeny. The mutational landscape of normal lymphocytes chronicles the off-target effects of programmed genome engineering during immunological diversification and the consequences of differentiation, proliferation and residency in diverse microenvironments.
Assuntos
Linfócitos , Mutação , Linfócitos B/citologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linfócitos B/patologia , Diferenciação Celular , Proliferação de Células , Microambiente Celular , Dano ao DNA/genética , Dano ao DNA/efeitos da radiação , Centro Germinativo/citologia , Centro Germinativo/imunologia , Humanos , Memória Imunológica/genética , Linfócitos/citologia , Linfócitos/imunologia , Linfócitos/metabolismo , Linfócitos/patologia , Neoplasias/genética , Neoplasias/patologiaRESUMO
ABSTRACT: Acquisition of a hyperdiploid (HY) karyotype or immunoglobulin heavy chain (IgH) translocations are considered key initiating events in multiple myeloma (MM). To explore if other genomic events can precede these events, we analyzed whole-genome sequencing data from 1173 MM samples. By integrating molecular time and structural variants within early chromosomal duplications, we indeed identified pregain deletions in 9.4% of patients with an HY karyotype without IgH translocations, challenging acquisition of an HY karyotype as the earliest somatic event. Remarkably, these deletions affected tumor suppressor genes (TSGs) and/or oncogenes in 2.4% of patients with an HY karyotype without IgH translocations, supporting their role in MM pathogenesis. Furthermore, our study points to postgain deletions as novel driver mechanisms in MM. Using multiomics approaches to investigate their biologic impact, we found associations with poor clinical outcome in newly diagnosed patients and profound effects on both the oncogene and TSG activity despite the diploid gene status. Overall, this study provides novel insights into the temporal dynamics of genomic alterations in MM.
Assuntos
Mieloma Múltiplo , Humanos , Mieloma Múltiplo/genética , Translocação Genética , Cadeias Pesadas de Imunoglobulinas/genética , Aberrações Cromossômicas , Deleção de Genes , Masculino , Feminino , Genes Supressores de TumorRESUMO
All normal somatic cells are thought to acquire mutations, but understanding of the rates, patterns, causes and consequences of somatic mutations in normal cells is limited. The uterine endometrium adopts multiple physiological states over a lifetime and is lined by a gland-forming epithelium1,2. Here, using whole-genome sequencing, we show that normal human endometrial glands are clonal cell populations with total mutation burdens that increase at about 29 base substitutions per year and that are many-fold lower than those of endometrial cancers. Normal endometrial glands frequently carry 'driver' mutations in cancer genes, the burden of which increases with age and decreases with parity. Cell clones with drivers often originate during the first decades of life and subsequently progressively colonize the epithelial lining of the endometrium. Our results show that mutational landscapes differ markedly between normal tissues-perhaps shaped by differences in their structure and physiology-and indicate that the procession of neoplastic change that leads to endometrial cancer is initiated early in life.
Assuntos
Análise Mutacional de DNA , Endométrio/citologia , Endométrio/metabolismo , Epitélio/metabolismo , Saúde , Mutação , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/genética , Carcinogênese/genética , Células Clonais/citologia , Neoplasias do Endométrio/genética , Endométrio/patologia , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Epitélio/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Paridade/genética , Fatores de Tempo , Adulto JovemRESUMO
Patients treated with cytotoxic therapies, including autologous stem cell transplantation, are at risk for developing therapy-related myeloid neoplasms (tMN). Preleukemic clones (ie, clonal hematopoiesis [CH]) are detectable years before the development of these aggressive malignancies, although the genomic events leading to transformation and expansion are not well defined. Here, by leveraging distinctive chemotherapy-associated mutational signatures from whole-genome sequencing data and targeted sequencing of prechemotherapy samples, we reconstructed the evolutionary life-history of 39 therapy-related myeloid malignancies. A dichotomy was revealed, in which neoplasms with evidence of chemotherapy-induced mutagenesis from platinum and melphalan were hypermutated and enriched for complex structural variants (ie, chromothripsis), whereas neoplasms with nonmutagenic chemotherapy exposures were genomically similar to de novo acute myeloid leukemia. Using chemotherapy-associated mutational signatures as temporal barcodes linked to discrete clinical exposure in each patient's life, we estimated that several complex events and genomic drivers were acquired after chemotherapy was administered. For patients with prior multiple myeloma who were treated with high-dose melphalan and autologous stem cell transplantation, we demonstrate that tMN can develop from either a reinfused CH clone that escapes melphalan exposure and is selected after reinfusion, or from TP53-mutant CH that survives direct myeloablative conditioning and acquires melphalan-induced DNA damage. Overall, we revealed a novel mode of tMN progression that is not reliant on direct mutagenesis or even exposure to chemotherapy. Conversely, for tMN that evolve under the influence of chemotherapy-induced mutagenesis, distinct chemotherapies not only select preexisting CH but also promote the acquisition of recurrent genomic drivers.
Assuntos
Antineoplásicos , Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Segunda Neoplasia Primária , Humanos , Melfalan , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante Autólogo/efeitos adversos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Segunda Neoplasia Primária/induzido quimicamente , Segunda Neoplasia Primária/genética , Antineoplásicos/farmacologiaRESUMO
Analysis of the genetic basis for multiple myeloma (MM) has informed many of our current concepts of the biology that underlies disease initiation and progression. Studying these events in further detail is predicted to deliver important insights into its pathogenesis, prognosis and treatment. Information from whole genome sequencing of structural variation is revealing the role of these events as drivers of MM. In particular, we discuss how the insights we have gained from studying chromothripsis suggest that it can be used to provide information on disease initiation and that, as a consequence, it can be used for the clinical classification of myeloma precursor diseases allowing for early intervention and prognostic determination. For newly diagnosed MM, the integration of information on the presence of chromothripsis has the potential to significantly enhance current risk prediction strategies and to better characterize patients with high-risk disease biology. In this article we summarize the genetic basis for MM and the role played by chromothripsis as a critical pathogenic factor active at early disease phases.
Assuntos
Cromotripsia , Mieloma Múltiplo , Humanos , Mieloma Múltiplo/diagnóstico , Mieloma Múltiplo/genética , Mieloma Múltiplo/patologia , Sequenciamento Completo do GenomaRESUMO
CD19-directed chimeric antigen receptor (CAR-19) T cells are groundbreaking immunotherapies approved for use against large B-cell lymphomas. Although host inflammatory and tumor microenvironmental markers associate with efficacy and resistance, the tumor-intrinsic alterations underlying these phenomena remain undefined. CD19 mutations associate with resistance but are uncommon, and most patients with relapsed disease retain expression of the wild-type receptor, implicating other genomic mechanisms. We therefore leveraged the comprehensive resolution of whole-genome sequencing to assess 51 tumor samples from 49 patients with CAR-19-treated large B-cell lymphoma. We found that the pretreatment presence of complex structural variants, APOBEC mutational signatures, and genomic damage from reactive oxygen species predict CAR-19 resistance. In addition, the recurrent 3p21.31 chromosomal deletion containing the RHOA tumor suppressor was strongly enriched in patients for whom CAR T-cell therapy failed. Pretreatment reduced expression or monoallelic loss of CD19 did not affect responses, suggesting CAR-19 therapy success and resistance are related to multiple mechanisms. Our study showed that tumor-intrinsic genomic alterations are key among the complex interplay of factors that underlie CAR-19 efficacy and resistance for large B-cell lymphomas.
Assuntos
Linfoma Difuso de Grandes Células B , Receptores de Antígenos Quiméricos , Antígenos CD19 , Genômica , Humanos , Imunoterapia Adotiva , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/terapia , Receptores de Antígenos de Linfócitos T/genética , Linfócitos T , Falha de TratamentoRESUMO
DIS3 gene mutations occur in roughly 10% of patients with multiple myeloma (MM); furthermore, DIS3 expression can be affected by monosomy 13 and del(13q), which occur in approximately 40% of MM cases. Despite several reports on the prevalence of DIS3 mutations, their contribution to the pathobiology of MM remains largely unknown. We took advantage of the large public CoMMpass dataset to investigate the spectrum of DIS3 mutations in MM and its impact on the transcriptome and clinical outcome. We found that the clinical relevance of DIS3 mutations strictly depended on the co-occurrence of del(13q). In particular, bi-allelic DIS3 lesions significantly affected progression-free survival, independently of other predictors of poor clinical outcome, while mono-allelic events mostly affected overall survival. As expected, DIS3 mutations affect the MM transcriptome involving cellular processes and signaling pathways associated with RNA metabolism, and the deregulation of a large number of long non-coding RNA, among which we identified five distinct transcripts as independent predictors of poorer overall survival and nine of worse progression-free survival, with two (AC015982.2 and AL445228.3) predicting both unfavorable outcomes. These findings strongly prompt further studies investigating the relevance of these long non-coding RNA in MM.
Assuntos
Complexo Multienzimático de Ribonucleases do Exossomo , Mieloma Múltiplo , RNA Longo não Codificante , Complexo Multienzimático de Ribonucleases do Exossomo/genética , Complexo Multienzimático de Ribonucleases do Exossomo/metabolismo , Humanos , Mieloma Múltiplo/genética , Mutação , TranscriptomaRESUMO
Nodal peripheral T-cell lymphoma not otherwise specified (PTCL-NOS) remains a diagnosis encompassing a heterogenous group of PTCL cases not fitting criteria for more homogeneous subtypes. They are characterized by a poor clinical outcome when treated with anthracycline-containing regimens. A better understanding of their biology could improve prognostic stratification and foster the development of novel therapeutic approaches. Recent targeted and whole exome sequencing studies have shown recurrent copy number abnormalities (CNAs) with prognostic significance. Here, investigating 5 formalin-fixed, paraffin embedded cases of PTCL-NOS by whole genome sequencing (WGS), we found a high prevalence of structural variants and complex events, such as chromothripsis likely responsible for the observed CNAs. Among them, CDKN2A and PTEN deletions emerged as the most frequent aberration, as confirmed in a final cohort of 143 patients with nodal PTCL. The incidence of CDKN2A and PTEN deletions among PTCL-NOS was 46% and 26%, respectively. Furthermore, we found that co-occurrence of CDKN2A and PTEN deletions is an event associated with PTCL-NOS with absolute specificity. In contrast, these deletions were rare and never co-occurred in angioimmunoblastic and anaplastic lymphomas. CDKN2A deletion was associated with shorter overall survival in multivariate analysis corrected by age, IPI, transplant eligibility and GATA3 expression (adjusted HR =2.53; 95% CI 1.006-6.3; p=0.048). These data suggest that CDKN2A deletions may be relevant for refining the prognosis of PTCL-NOS and their significance should be evaluated in prospective trials.
Assuntos
Inibidor p16 de Quinase Dependente de Ciclina/genética , Linfoma de Células T Periférico , Antraciclinas , Estudos de Coortes , Deleção de Genes , Humanos , Linfoma de Células T Periférico/diagnóstico , Linfoma de Células T Periférico/genética , PTEN Fosfo-Hidrolase , Prognóstico , Estudos ProspectivosRESUMO
The histological diagnosis of peripheral T-cell lymphoma (PTCL) can represent a challenge, particularly in the case of closely related entities such as angioimmunoblastic T-lymphoma (AITL), PTCL-not otherwise specified (PTCL-NOS), and ALK-negative anaplastic large-cell lymphoma (ALCL). Although gene expression profiling and next generations sequencing have been proven to define specific features recurrently associated with distinct entities, genomic-based stratifications have not yet led to definitive diagnostic criteria and/or entered into the routine clinical practice. Herein, to improve the current molecular classification between AITL and PTCL-NOS, we analyzed the transcriptional profiles from 503 PTCLs stratified according to their molecular configuration and integrated them with genomic data of recurrently mutated genes (RHOA G17V , TET2, IDH2 R172 , and DNMT3A) in 53 cases (39 AITLs and 14 PTCL-NOSs) included in the series. Our analysis unraveled that the mutational status of RHOA G17V , TET2, and DNMT3A poorly correlated, individually, with peculiar transcriptional fingerprints. Conversely, in IDH2 R172 samples a strong transcriptional signature was identified that could act as a surrogate for mutational status. The integrated analysis of clinical, mutational, and molecular data led to a simplified 19-gene signature that retains high accuracy in differentiating the main nodal PTCL entities. The expression levels of those genes were confirmed in an independent cohort profiled by RNA-sequencing.
Assuntos
Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Linfoma de Células T Periférico , Mutação , Proteínas de Neoplasias , Transcrição Gênica , Feminino , Humanos , Linfoma de Células T Periférico/genética , Linfoma de Células T Periférico/metabolismo , Masculino , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genéticaRESUMO
Minimal residual disease (MRD) tracking, by next generation sequencing of immunoglobulin sequences, is moving towards clinical implementation in multiple myeloma. However, there is only sparse information available to address whether clonal sequences remain stable for tracking over time, and to what extent light chain sequences are sufficiently unique for tracking. Here, we analyzed immunoglobulin repertoires from 905 plasma cell myeloma and healthy control samples, focusing on the third complementarity determining region (CDR3). Clonal heavy and/or light chain expression was identified in all patients at baseline, with one or more subclones related to the main clone in 3.2%. In 45 patients with 101 sequential samples, the dominant clonal CDR3 sequences remained identical over time, despite differential clonal evolution by whole exome sequencing in 49% of patients. The low frequency of subclonal CDR3 variants, and absence of evolution over time in active multiple myeloma, indicates that tumor cells at this stage are not under selective pressure to undergo antibody affinity maturation. Next, we establish somatic hypermutation and non-templated insertions as the most important determinants of light chain clonal uniqueness, identifying a potentially trackable sequence in the majority of patients. Taken together, we show that dominant clonal sequences identified at baseline are reliable biomarkers for long-term tracking of the malignant clone, including both IGH and the majority of light chain clones.
Assuntos
Regiões Determinantes de Complementaridade/genética , Rearranjo Gênico de Cadeia Pesada de Linfócito B , Rearranjo Gênico de Cadeia Leve de Linfócito B , Sequenciamento de Nucleotídeos em Larga Escala , Mieloma Múltiplo/patologia , Biomarcadores Tumorais , Medula Óssea/patologia , Células da Medula Óssea/metabolismo , Ensaios Clínicos como Assunto/estatística & dados numéricos , Evolução Clonal , Células Clonais/patologia , Genes de Imunoglobulinas , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Leves de Imunoglobulina/genética , Mieloma Múltiplo/genética , Neoplasia Residual/diagnóstico , Neoplasia Residual/genética , RNA Mensageiro/genética , RNA Neoplásico/genética , Hipermutação Somática de Imunoglobulina , Éxons VDJRESUMO
Allogeneic (allo) hematopoietic cell transplantation (HCT) currently represents the only potentially curative therapy for patients affected by multiple myeloma (MM). Up to 30% of patients in western countries do not have a matched donor. Haploidentical HCT (haplo-HCT) may be an option, but currently, there are little available data regarding this treatment. We analyzed survival outcomes of 30 heavily pretreated MM patients who received haplo-HCT with post-transplantation cyclophosphamide as graft-versus-host-disease (GVHD) prophylaxis. Median neutrophil and platelet engraftments at day +30 were 87% (95% confidence interval [CI], 66% to 95%) and 60% (95% CI, 40% to 75%), respectively. The cumulative incidences of relapse or progression of disease (PD) and nonrelapse mortality at 18 months were 42% (95% CI, 23% to 59%) and 10% (95% CI, 2% to 24%), respectively. The cumulative incidence of grade II to IV acute GVHD at day +100 was 29% (95% CI, 14% to 47%). The cumulative incidence of chronic GVHD at 18 months was 7% (95% CI, 1% to 21%). With a median follow-up in survivors of 25 months (range, 15 to 73 months), the 18-month progression-free survival (PFS) and overall survival (OS) were 33% (95% CI, 17% to 50%) and 63% (95% CI, 44% to 78%), respectively. No differences were observed between peripheral blood and bone marrow graft in terms of engraftment, GVHD, or PD incidence. Chemorefractory disease at transplantation was associated with a lower/reduced 18-month PFS (9% versus 47%, P = .01) and OS (45% versus 74%, P = .03). This was explained by a higher PD incidence (55% versus 33%, P = .05). In this multicenter study, we report encouraging results with haplo-HCT for patients with heavily pretreated MM.
Assuntos
Transplante de Medula Óssea , Ciclofosfamida/uso terapêutico , Doença Enxerto-Hospedeiro/prevenção & controle , Imunossupressores/uso terapêutico , Mieloma Múltiplo/terapia , Transplante de Células-Tronco de Sangue Periférico , Doença Aguda , Adulto , Idoso , Doença Crônica , Progressão da Doença , Feminino , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/mortalidade , Doença Enxerto-Hospedeiro/patologia , Teste de Histocompatibilidade , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/imunologia , Mieloma Múltiplo/mortalidade , Mieloma Múltiplo/patologia , Agonistas Mieloablativos/uso terapêutico , Recidiva , Estudos Retrospectivos , Irmãos , Análise de Sobrevida , Condicionamento Pré-Transplante/métodos , Transplante Haploidêntico , Doadores não RelacionadosRESUMO
BACKGROUND: The authors describe a family with a high penetrance of plasma cell dyscrasias, suggesting inheritance of an autosomal dominant risk allele. METHODS: The authors performed whole-exome sequencing and reported on a combined approach aimed at the identification of causative variants and risk loci, using the wealth of data provided by this approach. RESULTS: The authors identified gene mutations and single-nucleotide polymorphisms of potential significance, and pinpointed a known risk locus for myeloma as a potential area of transmissible risk in the family. CONCLUSIONS: To the authors' knowledge, the current study is the first to provide a whole-exome sequencing approach to such cases, and a framework analysis that could be applied to further understanding of the inherited risk of developing plasma cell dyscrasias. Cancer 2017;123:3701-3708. © 2017 American Cancer Society.
Assuntos
Alelos , Sequenciamento de Nucleotídeos em Larga Escala , Mutação , Paraproteinemias/genética , Penetrância , Polimorfismo de Nucleotídeo Único , Família , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/genética , Linhagem , RiscoRESUMO
Cytomegalovirus (CMV) replication after allogeneic hematopoietic stem cell transplantation (HSCT) was historically associated with increased nonrelapse mortality (NRM). More recently, different groups have reported an association between CMV replication and reduced risk of acute myeloid leukemia (AML) relapse. Given the conflicting results, we evaluated the impact of CMV replication and other covariates on the outcome of a retrospective cohort of 265 adults with B cell lymphoma receiving allogeneic HSCT from HLA-identical siblings or alternative donors. In time-dependent multivariate analysis, CMV replication, evaluated by pp65 antigenemia, had no independent effect on the risk of relapse (hazard ratio [HR], 1.0; 95% confidence interval [CI], .6 to 1.6; P = .9), although it was associated with a reduced overall survival (HR, 2.0; 95% CI, 1.3 to 3.2; P = .001) and an increased NRM (HR, 2.5; 95% CI, 1.1 to 5.3; P = .01). Consistently, donor and/or recipient CMV seropositivity were not associated with a different outcome relative to CMV double-negative serostatus. In multivariate models, a diagnosis of follicular lymphoma (P < .0001) and pretransplantation complete remission status (P < .0001) were the main independent predictors for improved relapse-free survival. In summary, contrary to what is observed in patients with AML, this report identifies no independent role for CMV replication or serostatus on the relapse of patients with B cell lymphomas undergoing allogeneic HSCT.
Assuntos
Infecções por Citomegalovirus/virologia , Citomegalovirus/fisiologia , Transplante de Células-Tronco Hematopoéticas/métodos , Linfoma de Células B/terapia , Linfoma de Células B/virologia , Condicionamento Pré-Transplante/métodos , Replicação Viral/fisiologia , Adolescente , Adulto , Idoso , Estudos de Coortes , Infecções por Citomegalovirus/sangue , Infecções por Citomegalovirus/etiologia , Feminino , Humanos , Linfoma de Células B/sangue , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Transplante Homólogo , Resultado do Tratamento , Adulto JovemRESUMO
NOTCH1 mutations have recently emerged as new genetic lesions significantly correlated with survival in chronic lymphocytic leukaemia (CLL). We performed deep next generation sequencing of the NOTCH1 mutation hotspot in 384 cases at diagnosis, including 100 monoclonal B cell lymphocytosis (MBL) and 284 Binet stage A CLL cases, enrolled in the Gruppo Italiano Studio Linfomi O-CLL1 multicentre trial. The NOTCH1 c.7541_7542delCT dinucleotide deletion was detected and confirmed by an extremely sensitive polymerase chain reaction-based approach in 11% of MBL and 13·4% of CLL patients. Remarkably, the NOTCH1 mutation was often observed at low clonal level, mainly in MBL patients. Sequential analyses in a fraction of cases showed that the NOTCH1 mutation generally does not occur during the disease course and that the mutational load in positive cases tends to be stable over time. NOTCH1-mutated cases, even at low clonal level, displayed a significant reduction in median progression-free survival, although NOTCH1 mutation lost its prognostic impact in a multivariate analysis including 11q and/or 17p deletion, IGHV mutational status, and MBL or CLL status. Our data highlight the importance of using highly sensitive methods to measure NOTCH1 mutations, in order to improve prognostic stratification and obtain useful information for potential therapeutic approaches.
Assuntos
Biomarcadores Tumorais/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Leucemia Linfocítica Crônica de Células B/genética , Mutação , Receptor Notch1/genética , Adulto , Idoso , Linfócitos B , Análise Mutacional de DNA/métodos , Feminino , Frequência do Gene , Humanos , Estimativa de Kaplan-Meier , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/patologia , Linfocitose/diagnóstico , Linfocitose/genética , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Estadiamento de Neoplasias , Reação em Cadeia da Polimerase/métodos , PrognósticoRESUMO
Trisomy 12 (+12) is the third most frequent cytogenetic aberration in chronic lymphocytic leukaemia (CLL) retrievable both as the sole chromosomal abnormality or in association with additional alterations. NOTCH1 mutations are known to be more prevalent among +12 patients, whereas mutations of FBXW7, a gene involved in NOTCH1 degradation, that lead to the constitutional activation of NOTCH1 have not been investigated in this setting. We analyzed a unicentric cohort of 44 +12 patients with CLL for mutations of TP53, NOTCH1 and FBXW7 genes, and we correlated them with B-cell receptor (BCR) configurations. FBXW7, TP53 and NOTCH1 mutations were identified in 4.5%, 6.8% and 18.2% of patients, respectively. FBXW7 and NOTCH1 mutations appeared in a mutually exclusive fashion, suggesting that both aberrations might affect the same biological pathway. We found that 44.1% of +12 CLL patients had stereotyped B-cell receptors, which is significantly higher than that observed in patients with CLL and no +12 (27%, p = 0.01). Subsets #1, #8, #10, #28 and #59 were the most represented stereotyped patterns, and IGHV4-39*01 was the gene configuration most commonly used. There was a significantly higher risk for Richter's syndrome (RS) transformation in patients with NOTCH1 or FBXW7 mutations, with four of the seven (57%) patients developing RS and characterized at least by one of the two abnormalities. These observations suggest that, similarly to the aberrations of NOTCH1, FBXW7 gene mutations may also result in cell proliferation and evasion from apoptosis in patients with +12 CLL. Together with the extremely high frequency of stereotyped BCRs and RS transformation, these abnormalities appear to cluster in these CLL patients with additional chromosome 12, suggesting a connection with the prognosis of the disease.
Assuntos
Cromossomos Humanos Par 12 , DNA de Neoplasias/genética , Rearranjo Gênico do Linfócito B , Leucemia Linfocítica Crônica de Células B/genética , Mutação , Trissomia , Idoso , Sequência de Aminoácidos , Animais , Proteínas de Ciclo Celular/genética , Transformação Celular Neoplásica/genética , Células Clonais/patologia , Sequência Conservada , Análise Mutacional de DNA , Progressão da Doença , Proteínas F-Box/genética , Proteína 7 com Repetições F-Box-WD , Feminino , Rearranjo Gênico de Cadeia Pesada de Linfócito B , Genes de Imunoglobulinas , Genes p53 , Humanos , Hibridização in Situ Fluorescente , Interfase/genética , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Células-Tronco Neoplásicas/patologia , Receptor Notch1/genética , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , Síndrome , Ubiquitina-Proteína Ligases/genéticaRESUMO
Chronic lymphocytic leukemia (CLL) is frequently complicated by secondary autoimmune cytopenias (AIC) represented by autoimmune hemolytic anemia (AIHA), immune thrombocytopenia (ITP), pure red cell aplasia, and autoimmune granulocytopenia. The distinction of immune cytopenias from cytopenias due to bone marrow infiltration, usually associated with a worse outcome and often requiring a different treatment, is mandatory. AIHA and ITP are more frequently found in patients with unfavorable biological risk factors for CLL. AIC secondary to CLL respond less favorably to standard treatments than their primary forms, and treating the underlying CLL with chemotherapy or monoclonal antibodies may ultimately be necessary.
Assuntos
Agranulocitose/etiologia , Anemia Hemolítica Autoimune/etiologia , Leucemia Linfocítica Crônica de Células B/complicações , Síndromes Paraneoplásicas/etiologia , Púrpura Trombocitopênica Idiopática/etiologia , Aplasia Pura de Série Vermelha/etiologia , Corticosteroides/uso terapêutico , Agranulocitose/sangue , Agranulocitose/diagnóstico , Agranulocitose/terapia , Anemia Hemolítica Autoimune/sangue , Anemia Hemolítica Autoimune/diagnóstico , Anemia Hemolítica Autoimune/terapia , Apresentação de Antígeno , Autoanticorpos/imunologia , Células Sanguíneas/imunologia , Transfusão de Componentes Sanguíneos , Células Clonais/imunologia , Terapia Combinada , Humanos , Imunoglobulina G/imunologia , Cadeias Pesadas de Imunoglobulinas/genética , Imunoglobulina M/imunologia , Imunossupressores/uso terapêutico , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/imunologia , Modelos Imunológicos , Células-Tronco Neoplásicas/imunologia , Síndromes Paraneoplásicas/sangue , Síndromes Paraneoplásicas/diagnóstico , Síndromes Paraneoplásicas/terapia , Prognóstico , Púrpura Trombocitopênica Idiopática/sangue , Púrpura Trombocitopênica Idiopática/diagnóstico , Púrpura Trombocitopênica Idiopática/terapia , Receptores de Antígenos de Linfócitos B/imunologia , Aplasia Pura de Série Vermelha/sangue , Aplasia Pura de Série Vermelha/diagnóstico , Aplasia Pura de Série Vermelha/terapia , Fatores de Risco , Esplenectomia , Subpopulações de Linfócitos T/imunologiaRESUMO
Multiple myeloma is a malignancy of bone-marrow-localized, isotype-switched plasma cells that secrete a monoclonal immunoglobulin and cause hyperCalcemia, Anemia, Renal failure, and lytic Bone disease. It is preceded, often for decades, by a relatively stable monoclonal gammopathy lacking these clinical and malignant features. Both conditions are characterized by the presence of types of immunoglobulin heavy gene translocations that dysregulate a cyclin D family gene on 11q13 (CCND1), 6p21 (CCND3), or 12q11 (CCND2), a maf family gene on 16q23 (MAF), 20q11 (MAFB), or 8q24 (MAFA), or NSD2/FGFR3 on 4p16, or the presence of hyperdiploidy. Subsequent loss of function of tumor suppressor genes and mutations activating MYC, RAS, NFkB, and cell cycle pathways are associated with the progression to malignant disease.
Assuntos
Gamopatia Monoclonal de Significância Indeterminada , Mieloma Múltiplo , Humanos , Mieloma Múltiplo/genética , Mieloma Múltiplo/terapia , Mieloma Múltiplo/patologia , Translocação Genética , Rearranjo Gênico , Mutação , Gamopatia Monoclonal de Significância Indeterminada/genética , Imunoglobulinas/genéticaRESUMO
PURPOSE: Whole-genome sequencing (WGS) of patients with newly diagnosed multiple myeloma (NDMM) has shown recurrent structural variant (SV) involvement in distinct regions of the genome (i.e., hotspots) and causing recurrent copy-number alterations. Together with canonical immunoglobulin translocations, these SVs are recognized as "recurrent SVs." More than half of SVs were not involved in recurrent events. The significance of these "rare SVs" has not been previously examined. EXPERIMENTAL DESIGN: In this study, we utilize 752 WGS and 591 RNA sequencing data from patients with NDMM to determine the role of rare SVs in myeloma pathogenesis. RESULTS: Ninety-four percent of patients harbored at least one rare SV event. Rare SVs showed an SV class-specific enrichment within genes and superenhancers associated with outlier gene expression. Furthermore, known myeloma driver genes recurrently impacted by point mutations were dysregulated by rare SVs. CONCLUSIONS: Overall, we demonstrate the association of rare SVs with aberrant gene expression supporting a potential driver role in myeloma pathogenesis.