RESUMEN
Oncogenic alterations underlying B-cell acute lymphoblastic leukemia (B-ALL) in adults remain incompletely elucidated. To uncover novel oncogenic drivers, we performed RNA sequencing and whole-genome analyses in a large cohort of unresolved B-ALL. We identified a novel subtype characterized by a distinct gene expression signature and the unique association of 2 genomic microdeletions. The 17q21.31 microdeletion resulted in a UBTF::ATXN7L3 fusion transcript encoding a chimeric protein. The 13q12.2 deletion resulted in monoallelic ectopic expression of the homeobox transcription factor CDX2, located 138 kb in cis from the deletion. Using 4C-sequencing and CRISPR interference experiments, we elucidated the mechanism of CDX2 cis-deregulation, involving PAN3 enhancer hijacking. CDX2/UBTF ALL (n = 26) harbored a distinct pattern of additional alterations including 1q gain and CXCR4 activating mutations. Within adult patients with Ph- B-ALL enrolled in GRAALL trials, patients with CDX2/UBTF ALL (n = 17/723, 2.4%) were young (median age, 31 years) and dramatically enriched in females (male/female ratio, 0.2, P = .002). They commonly presented with a pro-B phenotype ALL and moderate blast cell infiltration. They had poor response to treatment including a higher risk of failure to first induction course (19% vs 3%, P = .017) and higher post-induction minimal residual disease (MRD) levels (MRD ≥ 10-4, 93% vs 46%, P < .001). This early resistance to treatment translated into a significantly higher cumulative incidence of relapse (75.0% vs 32.4%, P = .004) in univariate and multivariate analyses. In conclusion, we discovered a novel B-ALL entity defined by the unique combination of CDX2 cis-deregulation and UBTF::ATXN7L3 fusion, representing a high-risk disease in young adults.
Asunto(s)
Factor de Transcripción CDX2 , Proteínas del Complejo de Iniciación de Transcripción Pol1 , Leucemia-Linfoma Linfoblástico de Células Precursoras B , Leucemia-Linfoma Linfoblástico de Células Precursoras , Factores de Transcripción , Adulto , Factor de Transcripción CDX2/genética , Femenino , Genes Homeobox , Humanos , Masculino , Neoplasia Residual/genética , Proteínas de Fusión Oncogénica , Proteínas del Complejo de Iniciación de Transcripción Pol1/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Factores de Transcripción/genéticaRESUMEN
Acute promyelocytic leukemia (APL) is often associated with activating FLT3 signaling mutations. These are highly related to hyperleukocytosis, a major adverse risk factor with chemotherapy-based regimens. APL is a model for oncogene-targeted therapies: all-trans retinoic acid (ATRA) and arsenic both target and degrade its ProMyelocytic Leukemia/Retinoic Acid Receptor α (PML/RARA) driver. The combined ATRA/arsenic regimen now cures virtually all patients with standard-risk APL. Although FLT3-internal tandem duplication (ITD) was an adverse risk factor for historical ATRA/chemotherapy regimens, the molecular bases for this effect remain unknown. Using mouse APL models, we unexpectedly demonstrate that FLT3-ITD severely blunts ATRA response. Remarkably, although the transcriptional output of initial ATRA response is unaffected, ATRA-induced PML/RARA degradation is blunted, as is PML nuclear body reformation and activation of P53 signaling. Critically, the combination of ATRA and arsenic fully rescues therapeutic response in FLT3-ITD APLs, restoring PML/RARA degradation, PML nuclear body reformation, P53 activation, and APL eradication. Moreover, arsenic targeting of normal PML also contributes to APL response in vivo. These unexpected results explain the less favorable outcome of FLT3-ITD APLs with ATRA-based regimens, and stress the key role of PML nuclear bodies in APL eradication by the ATRA/arsenic combination.
Asunto(s)
Antineoplásicos/uso terapéutico , Arsénico/uso terapéutico , Leucemia Promielocítica Aguda/tratamiento farmacológico , Tretinoina/uso terapéutico , Tirosina Quinasa 3 Similar a fms/genética , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Femenino , Leucemia Promielocítica Aguda/genética , Ratones Endogámicos C57BL , MutaciónRESUMEN
Germline DDX41 mutations are involved in familial myelodysplastic syndromes (MDSs) and acute myeloid leukemias (AMLs). We analyzed the prevalence and characteristics of DDX41-related myeloid malignancies in an unselected cohort of 1385 patients with MDS or AML. Using targeted next-generation sequencing, we identified 28 different germline DDX41 variants in 43 unrelated patients, which we classified as causal (n = 21) or unknown significance (n = 7) variants. We focused on the 33 patients having causal variants, representing 2.4% of our cohort. The median age was 69 years; most patients were men (79%). Only 9 patients (27%) had a family history of hematological malignancy, and 15 (46%) had a personal history of cytopenia years before MDS/AML diagnosis. Most patients had a normal karyotype (85%), and the most frequent somatic alteration was a second DDX41 mutation (79%). High-risk DDX41 MDS/AML patients treated with intensive chemotherapy (n = 9) or azacitidine (n = 11) had an overall response rate of 100% or 73%, respectively, with a median overall survival of 5.2 years. Our study highlights that germline DDX41 mutations are relatively common in adult MDS/AML, often without known family history, arguing for systematic screening. Salient features of DDX41-related myeloid malignancies include male preponderance, frequent preexisting cytopenia, additional somatic DDX41 mutation, and relatively good outcome.
Asunto(s)
ARN Helicasas DEAD-box/genética , Leucemia Mieloide Aguda/genética , Síndromes Mielodisplásicos/genética , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Mutación de Línea Germinal , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Bone marrow (BM) failure (BMF) in children and young adults is often suspected to be inherited, but in many cases diagnosis remains uncertain. We studied a cohort of 179 patients (from 173 families) with BMF of suspected inherited origin but unresolved diagnosis after medical evaluation and Fanconi anemia exclusion. All patients had cytopenias, and 12.0% presented ≥5% BM blast cells. Median age at genetic evaluation was 11 years; 20.7% of patients were aged ≤2 years and 36.9% were ≥18 years. We analyzed genomic DNA from skin fibroblasts using whole-exome sequencing, and were able to assign a causal or likely causal germ line mutation in 86 patients (48.0%), involving a total of 28 genes. These included genes in familial hematopoietic disorders (GATA2, RUNX1), telomeropathies (TERC, TERT, RTEL1), ribosome disorders (SBDS, DNAJC21, RPL5), and DNA repair deficiency (LIG4). Many patients had an atypical presentation, and the mutated gene was often not clinically suspected. We also found mutations in genes seldom reported in inherited BMF (IBMF), such as SAMD9 and SAMD9L (N = 16 of the 86 patients, 18.6%), MECOM/EVI1 (N = 6, 7.0%), and ERCC6L2 (N = 7, 8.1%), each of which was associated with a distinct natural history; SAMD9 and SAMD9L patients often experienced transient aplasia and monosomy 7, whereas MECOM patients presented early-onset severe aplastic anemia, and ERCC6L2 patients, mild pancytopenia with myelodysplasia. This study broadens the molecular and clinical portrait of IBMF syndromes and sheds light on newly recognized disease entities. Using a high-throughput sequencing screen to implement precision medicine at diagnosis can improve patient management and family counseling.
Asunto(s)
Enfermedades de la Médula Ósea/genética , Mutación de Línea Germinal , Adolescente , Enfermedades de la Médula Ósea/epidemiología , Niño , Preescolar , Estudios de Cohortes , Análisis Mutacional de ADN , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Lactante , Recién Nacido , Masculino , Síndromes Mielodisplásicos/epidemiología , Síndromes Mielodisplásicos/genética , Secuenciación del ExomaAsunto(s)
Predisposición Genética a la Enfermedad/genética , Leucemia/genética , Síndromes Mielodisplásicos/genética , Xerodermia Pigmentosa/genética , Cariotipo Anormal , Adolescente , Adulto , Niño , Reparación del ADN/genética , Proteínas de Unión al ADN/genética , Femenino , Efecto Fundador , Genes p53/genética , Humanos , Masculino , Mutación , Proteína p53 Supresora de Tumor/genética , Xerodermia Pigmentosa/complicaciones , Adulto JovenAsunto(s)
Mutación , Recurrencia Local de Neoplasia/patología , Factor de Transcripción PAX5/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/clasificación , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patología , Adulto , Estudios de Cohortes , Estudios de Seguimiento , Humanos , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/terapia , Pronóstico , Trasplante de Células Madre , Tasa de Supervivencia , Trasplante HomólogoRESUMEN
Cobblestone lissencephaly is a peculiar brain malformation with characteristic radiological anomalies. It is defined as cortical dysplasia that results when neuroglial overmigration into the arachnoid space forms an extracortical layer that produces agyria and/or a "cobblestone" brain surface and ventricular enlargement. Cobblestone lissencephaly is pathognomonic of a continuum of autosomal-recessive diseases characterized by cerebral, ocular, and muscular deficits. These include Walker-Warburg syndrome, muscle-eye-brain disease, and Fukuyama muscular dystrophy. Mutations in POMT1, POMT2, POMGNT1, LARGE, FKTN, and FKRP identified these diseases as alpha-dystroglycanopathies. Our exhaustive screening of these six genes, in a cohort of 90 fetal cases, led to the identification of a mutation in only 53% of the families, suggesting that other genes might also be involved. We therefore decided to perform a genome-wide study in two multiplex families. This allowed us to identify two additional genes: TMEM5 and ISPD. Because TMEM has a glycosyltransferase domain and ISPD has an isoprenoid synthase domain characteristic of nucleotide diP-sugar transferases, these two proteins are thought to be involved in the glycosylation of dystroglycan. Further screening of 40 families with cobblestone lissencephaly identified nonsense and frameshift mutations in another four unrelated cases for each gene, increasing the mutational rate to 64% in our cohort. All these cases displayed a severe phenotype of cobblestone lissencephaly A. TMEM5 mutations were frequently associated with gonadal dysgenesis and neural tube defects, and ISPD mutations were frequently associated with brain vascular anomalies.
Asunto(s)
Lisencefalia de Cobblestone/genética , Proteínas de la Membrana/genética , Mutación , Nucleotidiltransferasas/genética , Alelos , Lisencefalia de Cobblestone/diagnóstico , Consanguinidad , Exones , Familia , Feto/metabolismo , Feto/patología , Orden Génico , Genotipo , Humanos , Intrones , PentosiltransferasaRESUMEN
BACKGROUND: Pelizaeus-Merzbacher disease (PMD) is an X-linked dysmyelinating disorder characterized by nystagmus, hypotonia, ataxia, progressive spasticity, and cognitive decline. PMD classically results from a duplication of a genomic segment encompassing the entire PLP1 gene. Since the PLP1 gene is located in Xq22, PMD affects mostly boys. METHODS AND RESULTS: Here we report the case of a girl with typical PMD. Copy number analysis of the PLP1 locus revealed a duplication of the entire gene and FISH analysis showed that the extra copy of the PLP1 gene was actually inserted in chromosome 1p36. This insertion of an additional copy of PLP1 in an autosome led to a functional duplication irrespective of the X-inactivation pattern. Subsequent overexpression of PLP1 was the cause of the PMD phenotype observed in this girl. Further sequencing of the breakpoint junction revealed a microhomology and thus suggested a replication based mechanism (such as FoSTeS or MMBIR). CONCLUSION: This case emphasizes the susceptibility of the PLP1 locus to complex rearrangement likely driven by the Xq22 local genomic architecture. In addition, careful consideration should be given to girls with classical PMD clinical features since they usually experience complex PLP1 genomic alteration with a distinct risk of inheritance.
Asunto(s)
Cromosomas Humanos Par 1/genética , Duplicación de Gen/genética , Mutagénesis Insercional/genética , Proteína Proteolipídica de la Mielina/genética , Enfermedad de Pelizaeus-Merzbacher/genética , Femenino , Humanos , Hibridación Fluorescente in Situ , Imagen por Resonancia Magnética , Análisis por Micromatrices , Enfermedad de Pelizaeus-Merzbacher/patología , Inactivación del Cromosoma X/genéticaRESUMEN
BACKGROUND: Metabolic syndrome (MS) is an emerging risk factor in hepatocellular carcinoma (HCC). HCC related to MS may occur either in advanced fibrosis or before the development of cirrhosis, suggesting involvement of different molecular pathways according to the features of background liver. OBJECTIVE: To investigate genomic aberrations in HCC related to MS in order to identify new target genes involved in liver carcinogenesis. METHODS: Chromosomal aberrations of HCC obtained from 20 patients with MS (HCC/MS) were studied by comparative genomic hybridisation and compared with HCC related to hepatitis C virus (HCV) infection (HCC/HCV, n=10) and, within the group of HCC with MS, according to the condition of the background liver (presence or absence of significant fibrosis). RESULTS: Among the most frequent chromosomal alterations observed in HCC, 6p21.1 amplification had a higher incidence in HCC/MS than in HCC/HCV (60% vs 20%, p<0.01). Advanced fibrosis/cirrhosis in the peritumoral liver was the only clinicopathological factor associated with the 6p21.1 amplicon in HCC/MS. Increased expression of cullin7 (CUL7), a gene located at the 6p21.1 locus, was demonstrated in HCC with the 6p21.1 amplicon, in parallel with a decrease in cyclin D1 expression. CUL7 downregulation using siRNA transfection in hepatoma cell lines induced significant cyclin D1 expression (by promoting its degradation), decreased cell proliferation and increased apoptosis. CONCLUSIONS: This study demonstrates specific genomic alterations in HCC/MS and points to CUL7 as a novel gene potentially involved in liver carcinogenesis associated with MS, the amplification of which might influence cell proliferation.
Asunto(s)
Carcinoma Hepatocelular/genética , Aberraciones Cromosómicas , Cromosomas Humanos Par 6/genética , Proteínas Cullin/genética , Neoplasias Hepáticas/genética , Síndrome Metabólico/complicaciones , Anciano , Anciano de 80 o más Años , Apoptosis , Western Blotting , Carcinoma Hepatocelular/etiología , Carcinoma Hepatocelular/patología , Proliferación Celular , Transformación Celular Neoplásica/genética , Proteínas Cullin/metabolismo , Ciclina D1/genética , Ciclina D1/metabolismo , Femenino , Expresión Génica , Hepatitis C/complicaciones , Humanos , Inmunohistoquímica , Cirrosis Hepática/etiología , Cirrosis Hepática/genética , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Hibridación de Ácido Nucleico , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
Fanconi anemia (FA) is a genetic condition associated with bone marrow (BM) failure, myelodysplasia (MDS), and acute myeloid leukemia (AML). We studied 57 FA patients with hypoplastic or aplastic anemia (n = 20), MDS (n = 18), AML (n = 11), or no BM abnormality (n = 8). BM samples were analyzed by karyotype, high-density DNA arrays with respect to paired fibroblasts, and by selected oncogene sequencing. A specific pattern of chromosomal abnormalities was found in MDS/AML, which included 1q+ (44.8%), 3q+ (41.4%), -7/7q (17.2%), and 11q- (13.8%). Moreover, cryptic RUNX1/AML1 lesions (translocations, deletions, or mutations) were observed for the first time in FA (20.7%). Rare mutations of NRAS, FLT3-ITD, MLL-PTD, ERG amplification, and ZFP36L2-PRDM16 translocation, but no TP53, TET2, CBL, NPM1, and CEBPα mutations were found. Frequent homozygosity regions were related not to somatic copy-neutral loss of heterozygosity but to consanguinity, suggesting that homologous recombination is not a common progression mechanism in FA. Importantly, the RUNX1 and other chromosomal/genomic lesions were found at the MDS/AML stages, except for 1q+, which was found at all stages. These data have implications for staging and therapeutic managing in FA patients, and also to analyze the mechanisms of clonal evolution and oncogenesis in a background of genomic instability and BM failure.
Asunto(s)
Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , Anemia de Fanconi/genética , Inestabilidad Genómica/genética , Leucemia Mieloide Aguda/genética , Síndromes Mielodisplásicos/genética , Adolescente , Adulto , Médula Ósea/fisiología , Niño , Preescolar , Anemia de Fanconi/complicaciones , Femenino , Dosificación de Gen/genética , Perfilación de la Expresión Génica , Regulación Leucémica de la Expresión Génica , Genes Supresores de Tumor , Homocigoto , Humanos , Leucemia Mieloide Aguda/etiología , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/etiología , Nucleofosmina , Polimorfismo de Nucleótido Simple , Adulto JovenRESUMEN
PML nuclear bodies (NB) are disrupted in PML-RARA-driven acute promyelocytic leukemia (APL). Arsenic trioxide (ATO) cures 70% of patients with APL, driving PML-RARA degradation and NB reformation. In non-APL cells, arsenic binding onto PML also amplifies NB formation. Yet, the actual molecular mechanism(s) involved remain(s) elusive. Here, we establish that PML NBs display some features of liquid-liquid phase separation and that ATO induces a gel-like transition. PML B-box-2 structure reveals an alpha helix driving B2 trimerization and positioning a cysteine trio to form an ideal arsenic-binding pocket. Altering either of the latter impedes ATO-driven NB assembly, PML sumoylation, and PML-RARA degradation, mechanistically explaining clinical ATO resistance. This B2 trimer and the C213 trio create an oxidation-sensitive rheostat that controls PML NB assembly dynamics and downstream signaling in both basal state and during stress response. These findings identify the structural basis for arsenic targeting of PML that could pave the way to novel cancer drugs. SIGNIFICANCE: Arsenic curative effects in APL rely on PML targeting. We report a PML B-box-2 structure that drives trimer assembly, positioning a cysteine trio to form an arsenic-binding pocket, which is disrupted in resistant patients. Identification of this ROS-sensitive triad controlling PML dynamics and functions could yield novel drugs. See related commentary by Salomoni, p. 2505. This article is featured in Selected Articles from This Issue, p. 2489.
Asunto(s)
Arsénico , Arsenicales , Leucemia Promielocítica Aguda , Humanos , Arsénico/farmacología , Cuerpos Nucleares de la Leucemia Promielocítica , Cisteína , Arsenicales/farmacología , Óxidos/farmacología , Trióxido de Arsénico/farmacología , Leucemia Promielocítica Aguda/tratamiento farmacológico , Leucemia Promielocítica Aguda/genética , Leucemia Promielocítica Aguda/metabolismo , Proteínas Oncogénicas , Proteínas de Fusión Oncogénica/genética , Proteínas de Fusión Oncogénica/metabolismoRESUMEN
Fanconi anemia (FA) patients experience chromosome instability, yielding hematopoietic stem/progenitor cell (HSPC) exhaustion and predisposition to poor-prognosis myeloid leukemia. Based on a longitudinal cohort of 335 patients, we performed clinical, genomic, and functional studies in 62 patients with clonal evolution. We found a unique pattern of somatic structural variants and mutations that shares features of BRCA-related cancers, the FA-hallmark being unbalanced, microhomology-mediated translocations driving copy-number alterations. Half the patients developed chromosome 1q gain, driving clonal hematopoiesis through MDM4 trisomy downmodulating p53 signaling later followed by secondary acute myeloid lukemia genomic alterations. Functionally, MDM4 triplication conferred greater fitness to murine and human primary FA HSPCs, rescued inflammation-mediated bone marrow failure, and drove clonal dominance in FA mouse models, while targeting MDM4 impaired leukemia cells in vitro and in vivo. Our results identify a linear route toward secondary leukemogenesis whereby early MDM4-driven downregulation of basal p53 activation plays a pivotal role, opening monitoring and therapeutic prospects.
Asunto(s)
Anemia de Fanconi , Leucemia , Humanos , Ratones , Animales , Anemia de Fanconi/genética , Hematopoyesis Clonal , Trisomía/genética , Proteína p53 Supresora de Tumor/genética , Leucemia/genética , Cromosomas , Hematopoyesis/genética , Proteínas Proto-Oncogénicas/genética , Proteínas de Ciclo Celular/genéticaRESUMEN
Mutations of the ten eleven translocation 2 gene (TET2) have recently been reported in myelodysplastic syndrome and myeloproliferative neoplasms. We analyzed the incidence and prognostic value of TET2 point mutations and other genomic alterations by direct sequencing and single nucleotide polymorphism microarray analysis in 111 de novo acute myeloid leukemia, who had all achieved complete remission (CR). Mutations were observed in 19 (17%) of the 111 patients compared with 10 (27%) of 36 patients who had failed to achieve CR (P = .2). In the 111 patients who had achieved CR, TET2 alterations were only significantly associated with NPM1 mutations but not with other pretreatment characteristics. TET2 gene status was not significantly correlated with disease-free survival and overall survival, both in the entire cohort and in patients with normal karyotype.
Asunto(s)
Proteínas de Unión al ADN/genética , Leucemia Mieloide Aguda/genética , Mutación/genética , Proteínas Proto-Oncogénicas/genética , Translocación Genética/genética , Adolescente , Adulto , Anciano , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Dioxigenasas , Femenino , Perfilación de la Expresión Génica , Humanos , Incidencia , Cariotipificación , Leucemia Mieloide Aguda/terapia , Masculino , Persona de Mediana Edad , Nucleofosmina , Análisis de Secuencia por Matrices de Oligonucleótidos , Polimorfismo de Nucleótido Simple/genética , Pronóstico , Inducción de Remisión , Tasa de Supervivencia , Adulto JovenRESUMEN
Membrane-less organelles are condensates formed by phase separation whose functions often remain enigmatic. Upon oxidative stress, PML scaffolds Nuclear Bodies (NBs) to regulate senescence or metabolic adaptation. PML NBs recruit many partner proteins, but the actual biochemical mechanism underlying their pleiotropic functions remains elusive. Similarly, PML role in embryonic stem cell (ESC) and retro-element biology is unsettled. Here we demonstrate that PML is essential for oxidative stress-driven partner SUMO2/3 conjugation in mouse ESCs (mESCs) or leukemia, a process often followed by their poly-ubiquitination and degradation. Functionally, PML is required for stress responses in mESCs. Differential proteomics unravel the KAP1 complex as a PML NB-dependent SUMO2-target in arsenic-treated APL mice or mESCs. PML-driven KAP1 sumoylation enables activation of this key epigenetic repressor implicated in retro-element silencing. Accordingly, Pml-/- mESCs re-express transposable elements and display 2-Cell-Like features, the latter enforced by PML-controlled SUMO2-conjugation of DPPA2. Thus, PML orchestrates mESC state by coordinating SUMO2-conjugation of different transcriptional regulators, raising new hypotheses about PML roles in cancer.
Asunto(s)
Arsénico , Sumoilación , Animales , Elementos Transponibles de ADN , Células Madre Embrionarias , Ratones , Cuerpos Nucleares , Factores de TranscripciónRESUMEN
Intra-tumor heterogeneity portends poor outcome in many cancers. In AML, a higher number of drivers worsens prognosis. The Shannon Index is a robust metric of clonal heterogeneity that accounts for the number of clones, but also their relative abundance. We show that a Shannon Index can be estimated from bulk sequencing, which is correlated (ρ = 0.76) with clonal diversity from single-colony genotyping. In a discovery cohort of 292 patients with sequencing of 43 genes, a higher number of drivers (HR = 1.18, P = 0.028) and a lower Shannon Index (HR = 0.68, P = 0.048), the latter reflecting clonal dominance, are independently associated with worse OS independently of European LeukemiaNet 2017 risk. These findings are validated in an independent cohort of 1184 patients with 111-gene sequencing (number of drivers HR = 1.16, P = 1 × 10-5, Shannon Index HR = 0.81, P = 0.007). By re-interrogating paired diagnosis/relapse exomes from 50 cytogenetically normal AMLs, we find clonal dominance at diagnosis to be correlated with the gain of a significantly higher number of mutations at relapse (P = 6 × 10-6), hence with clonal sweeping. Our results suggest that clonal dominance at diagnosis is associated with the presence of a leukemic phenotype allowing rapid expansion of new clones and driving relapse after chemotherapy.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores de Tumor/genética , Evolución Clonal , Regulación Neoplásica de la Expresión Génica , Leucemia Mieloide Aguda/patología , Femenino , Estudios de Seguimiento , Humanos , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/genética , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Tasa de SupervivenciaRESUMEN
Acute myeloid leukemia (AML) pathogenesis often involves a mutation in the NPM1 nucleolar chaperone, but the bases for its transforming properties and overall association with favorable therapeutic responses remain incompletely understood. Here we demonstrate that an oncogenic mutant form of NPM1 (NPM1c) impairs mitochondrial function. NPM1c also hampers formation of promyelocytic leukemia (PML) nuclear bodies (NB), which are regulators of mitochondrial fitness and key senescence effectors. Actinomycin D (ActD), an antibiotic with unambiguous clinical efficacy in relapsed/refractory NPM1c-AMLs, targets these primed mitochondria, releasing mitochondrial DNA, activating cyclic GMP-AMP synthase signaling, and boosting reactive oxygen species (ROS) production. The latter restore PML NB formation to drive TP53 activation and senescence of NPM1c-AML cells. In several models, dual targeting of mitochondria by venetoclax and ActD synergized to clear AML and prolong survival through targeting of PML. Our studies reveal an unexpected role for mitochondria downstream of NPM1c and implicate a mitochondrial/ROS/PML/TP53 senescence pathway as an effector of ActD-based therapies. SIGNIFICANCE: ActD induces complete remissions in NPM1-mutant AMLs. We found that NPM1c affects mitochondrial biogenesis and PML NBs. ActD targets mitochondria, yielding ROS which enforce PML NB biogenesis and restore senescence. Dual targeting of mitochondria with ActD and venetoclax sharply potentiates their anti-AML activities in vivo. This article is highlighted in the In This Issue feature, p. 2945.
Asunto(s)
Leucemia Mieloide Aguda , Proteínas Nucleares , Dactinomicina/farmacología , Dactinomicina/uso terapéutico , Humanos , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Mitocondrias/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , NucleofosminaRESUMEN
Bromodomain and Extra-Terminal inhibitors (BETi) such as OTX015 are active in Acute Myeloid Leukaemias (AML). Their activity on Leukemic Stem Cells (LSCs) is less documented. We interrogated the anti-LSC activity of OTX015 in a niche-like long-term culture in 26 primary AML samples and validated our findings in vivo. OTX015 impaired LSCs in AMLs harbouring Core Binding Factor or KMT2A gene fusions, NPM1 or chromatin/spliceosome genes mutations, but not in those with aneuploidy/TP53 mutations. In four patients, we dissected the transcriptomic footprint of Bet inhibition on LSCs versus blasts. Our results can instruct future clinical trials of BETi in AML.
Asunto(s)
Antineoplásicos/farmacología , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Células Madre Neoplásicas/efectos de los fármacos , Proteínas/antagonistas & inhibidores , Animales , Antineoplásicos/uso terapéutico , Trasplante de Células Madre Hematopoyéticas , Humanos , Leucemia Mieloide Aguda/terapia , Ratones , Ratones Transgénicos , Mutación , Estadificación de Neoplasias , Células Madre Neoplásicas/patología , Células Madre Neoplásicas/fisiología , Nucleofosmina , Oncogenes/genética , Proteínas/genética , Resultado del Tratamiento , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Deletion of chromosome 6q is a well-recognized abnormality found in poor-prognosis T-cell acute lymphoblastic leukemia (T-ALL). Using integrated genomic approaches, we identified two candidate haploinsufficient genes contiguous at 6q14, SYNCRIP (encoding hnRNP-Q) and SNHG5 (that hosts snoRNAs), both involved in regulating RNA maturation and translation. Combined silencing of both genes, but not of either gene alone, accelerated leukemogeneis in a Tal1/Lmo1/Notch1-driven mouse model, demonstrating the tumor-suppressive nature of the two-gene region. Proteomic and translational profiling of cells in which we engineered a short 6q deletion by CRISPR/Cas9 genome editing indicated decreased ribosome and mitochondrial activities, suggesting that the resulting metabolic changes may regulate tumor progression. Indeed, xenograft experiments showed an increased leukemia-initiating cell activity of primary human leukemic cells upon coextinction of SYNCRIP and SNHG5. Our findings not only elucidate the nature of 6q deletion but also highlight the role of ribosomes and mitochondria in T-ALL tumor progression. SIGNIFICANCE: The oncogenic role of 6q deletion in T-ALL has remained elusive since this chromosomal abnormality was first identified more than 40 years ago. We combined genomic analysis and functional models to show that the codeletion of two contiguous genes at 6q14 enhances malignancy through deregulation of a ribosome-mitochondria axis, suggesting the potential for therapeutic intervention.This article is highlighted in the In This Issue feature, p. 1494.
Asunto(s)
Deleción Cromosómica , Ribonucleoproteínas Nucleares Heterogéneas/genética , Leucemia de Células T/genética , ARN Largo no Codificante/genética , Ribosomas/metabolismo , Animales , Línea Celular Tumoral , Cromosomas Humanos Par 6 , Progresión de la Enfermedad , Perfilación de la Expresión Génica , Haploinsuficiencia , Ribonucleoproteínas Nucleares Heterogéneas/metabolismo , Humanos , Leucemia de Células T/metabolismo , Leucemia de Células T/patología , Ratones , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patología , Interferencia de ARN , ARN Largo no Codificante/metabolismo , Trasplante HeterólogoRESUMEN
The regulatory microRNA miR-150 is involved in the development of hemopathies and is downregulated in T-lymphomas, such as anaplastic large-cell lymphoma (ALCL) tumors. ALCL is defined by the presence or absence of translocations that activate the anaplastic lymphoma kinase (ALK), with nucleophosmin-ALK (NPM-ALK) fusions being the most common. Here, we compared samples of primary NPM-ALK(+) and NPM-ALK(-) ALCL to investigate the role of miR-150 downstream of NPM-ALK. Methylation of the MIR150 gene was substantially elevated in NPM-ALK(+) biopsies and correlated with reduced miR-150 expression. In NPM-ALK(+) cell lines, DNA hypermethylation-mediated miR-150 repression required ALK-dependent pathways, as ALK inhibition restored miR-150 expression. Moreover, epigenetic silencing of miR-150 was due to the activation of STAT3, a major downstream substrate of NPM-ALK, in cooperation with DNA methyltransferase 1 (DNMT1). Accordingly, miR-150 repression was turned off following treatment with the DNMT inhibitor, decitabine. In murine NPM-ALK(+) xenograft models, miR-150 upregulation induced antineoplastic activity. Treatment of crizotinib-resistant NPM-ALK(+) KARPAS-299-CR06 cells with decitabine or ectopic miR-150 expression reduced viability and growth. Altogether, our results suggest that hypomethylating drugs, alone or in combination with other agents, may benefit ALK(+) patients harboring tumors resistant to crizotinib and other anti-ALK tyrosine kinase inhibitors (TKIs). Moreover, these results support further work on miR-150 in these and other ALK(+) malignancies.