RESUMO
Mutations in IDH1, IDH2, and TET2 are recurrently observed in myeloid neoplasms. IDH1 and IDH2 encode isocitrate dehydrogenase isoforms, which normally catalyze the conversion of isocitrate to α-ketoglutarate (α-KG). Oncogenic IDH1/2 mutations confer neomorphic activity, leading to the production of D-2-hydroxyglutarate (D-2-HG), a potent inhibitor of α-KG-dependent enzymes which include the TET methylcytosine dioxygenases. Given their mutual exclusivity in myeloid neoplasms, IDH1, IDH2, and TET2 mutations may converge on a common oncogenic mechanism. Contrary to this expectation, we observed that they have distinct, and even opposite, effects on hematopoietic stem and progenitor cells in genetically engineered mice. Epigenetic and single-cell transcriptomic analyses revealed that Idh2R172K and Tet2 loss-of-function have divergent consequences on the expression and activity of key hematopoietic and leukemogenic regulators. Notably, chromatin accessibility and transcriptional deregulation in Idh2R172K cells were partially disconnected from DNA methylation alterations. These results highlight unanticipated divergent effects of IDH1/2 and TET2 mutations, providing support for the optimization of genotype-specific therapies.
Assuntos
Proteínas de Ligação a DNA , Dioxigenases , Isocitrato Desidrogenase , Células-Tronco , Animais , Camundongos , Dioxigenases/genética , Proteínas de Ligação a DNA/genética , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/metabolismo , Ácidos Cetoglutáricos/metabolismo , Mutação , Neoplasias , Células-Tronco/metabolismoRESUMO
Progression to aggressive secondary acute myeloid leukaemia (sAML) poses a significant challenge in the management of myeloproliferative neoplasms (MPNs). Since the physiopathology of MPN is closely linked to the activation of interferon (IFN) signalling and that AML initiation and aggressiveness is driven by leukaemia stem cells (LSCs), we investigated these pathways in MPN to sAML progression. We found that high IFN signalling correlated with low LSC signalling in MPN and AML samples, while MPN progression and AML transformation were characterized by decreased IFN signalling and increased LSC signature. A high LSC to IFN expression ratio in MPN patients was associated with adverse clinical prognosis and higher colony forming potential. Moreover, treatment with hypomethylating agents (HMAs) activates the IFN signalling pathway in MPN cells by inducing a viral mimicry response. This response is characterized by double-stranded RNA (dsRNA) formation and MDA5/RIG-I activation. The HMA-induced IFN response leads to a reduction in LSC signature, resulting in decreased stemness. These findings reveal the frequent evasion of viral mimicry during MPN-to-sAML progression, establish the LSC-to-IFN expression ratio as a progression biomarker, and suggests that HMAs treatment can lead to haematological response in murine models by re-activating dsRNA-associated IFN signalling.
Assuntos
Leucemia Mieloide Aguda , Transtornos Mieloproliferativos , Humanos , Animais , Camundongos , Transtornos Mieloproliferativos/tratamento farmacológico , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/complicações , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Prognóstico , Biomarcadores , Interferons/uso terapêuticoRESUMO
Treatment results for patients with newly diagnosed FMS-like tyrosine kinase 3 (FLT3)-mutated (FLT3mut+) acute myeloid leukemia (AML) ineligible for intensive chemotherapy are disappointing. This multicenter, open-label, phase 3 trial randomized (2:1) untreated adults with FLT3mut+ AML ineligible for intensive induction chemotherapy to receive gilteritinib (120 mg/d orally) and azacitidine (GIL + AZA) or azacitidine (AZA) alone. The primary end point was overall survival (OS). At the interim analysis (August 26, 2020), a total of 123 patients were randomized to treatment (GIL + AZA, n = 74; AZA, n = 49). Subsequent AML therapy, including FLT3 inhibitors, was received by 20.3% (GIL + AZA) and 44.9% (AZA) of patients. Median OS was 9.82 (GIL + AZA) and 8.87 (AZA) months (hazard ratio, 0.916; 95% CI, 0.529-1.585; P = .753). The study was closed based on the protocol-specified boundary for futility. Median event-free survival was 0.03 month in both arms. Event-free survival defined by using composite complete remission (CRc) was 4.53 months for GIL + AZA and 0.03 month for AZA (hazard ratio, 0.686; 95% CI, 0.433-1.087; P = .156). CRc rates were 58.1% (GIL + AZA) and 26.5% (AZA) (difference, 31.4%; 95% CI, 13.1-49.7; P < .001). Adverse event (AE) rates were similar for GIL + AZA (100%) and AZA (95.7%); grade ≥3 AEs were 95.9% and 89.4%, respectively. Common AEs with GIL + AZA included pyrexia (47.9%) and diarrhea (38.4%). Gilteritinib steady-state trough concentrations did not differ between GIL + AZA and gilteritinib. GIL + AZA resulted in significantly higher CRc rates, although similar OS compared with AZA. Results support the safety/tolerability and clinical activity of upfront therapy with GIL + AZA in older/unfit patients with FLT3mut+ AML. This trial was registered at www.clinicaltrials.gov as #NCT02752035.
Assuntos
Azacitidina , Leucemia Mieloide Aguda , Adulto , Humanos , Idoso , Azacitidina/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/diagnóstico , Pirazinas/efeitos adversosRESUMO
Measurable residual disease (MRD) monitoring independently predicts long-term outcomes in patients with acute myeloid leukemia (AML). Of the various modalities available, multiparameter flow cytometry-based MRD analysis is widely used and relevant for patients without molecular targets. In the transplant (HCT) setting, the presence of MRD pre-HCT is associated with adverse outcomes. MRD-negative remission status pre-HCT was also associated with longer overall (OS) and progression-free survival and a lower risk of relapse. We hypothesize that the combination of disease risk and MRD at the time of first complete remission (CR1) could identify patients according to the benefit gained from HCT, especially for intermediate-risk patients. We performed a retrospective analysis comparing the outcomes of HCT versus non-HCT therapies based on MRD status in AML patients who achieved CR1. Time-dependent analysis was applied considering time-to-HCT as a time-dependent covariate and compared HCT versus non-HCT outcomes according to MRD status at CR1. Among 336 patients assessed at CR1, 35.1% were MRD positive (MRDpos) post-induction. MRDpos patients benefitted from HCT with improved OS and relapse-free survival (RFS), while no benefit was observed in MRDneg patients. In adverse-risk patients, HCT improved OS (HR for OS 0.55; p = 0.05). In intermediate-risk patients, HCT benefit was not significant for OS and RFS. Intermediate-risk MRDpos patients were found to have benefit from HCT with improved OS (HR 0.45, p = 0.04), RFS (HR 0.46, p = 0.02), and CIR (HR 0.41, p = 0.02). Our data underscore the benefit of HCT in adverse risk and MRDpos intermediate-risk AML patients.
Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Humanos , Citometria de Fluxo , Estudos Retrospectivos , Transplante Homólogo , Recidiva , Neoplasia Residual , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/terapia , PrognósticoRESUMO
Nucleophosmin-1 (NPM1)-mutated AML is a molecularly defined subtype typically associated with favorable treatment response and prognosis; however, its prognostic significance in AML evolving from an antecedent chronic myeloid malignancy is unknown. This study's primary objective was to determine the impact of mutated NPM1 on the prognosis of AML evolving from an antecedent chronic myeloid malignancy. We conducted a retrospective chart review including patients with NPM1-mutated de novo and sAML. sAML was defined as those with a preceding chronic-phase myeloid malignancy before diagnosis of AML. Of 575 NPM1-mutated patients eligible for inclusion in our study, 51 (8.9%) patients were considered to have sAML. The median time from diagnosis of NPM1-mutated chronic myeloid malignancy to sAML evolution was 3.6 months (0.5-79.3 months). No significant differences in leukemia-free (2-year LKFS 52.0% vs. 51.2%, p = .9922) or overall survival (2-year OS 56.3% vs. 49.4%, p = .4246) were observed between patients with NPM1-mutated de novo versus sAML. Our study suggests that evolution from a preceding myeloid malignancy is not a significant predictor of poor prognosis in the setting of an NPM1 mutation. Our study demonstrated a short time to progression to sAML in most patients, which further supports the consideration of NPM1 as an AML-defining mutation.
RESUMO
The use of liquid biopsies for cancer detection and management is rapidly gaining prominence1. Current methods for the detection of circulating tumour DNA involve sequencing somatic mutations using cell-free DNA, but the sensitivity of these methods may be low among patients with early-stage cancer given the limited number of recurrent mutations2-5. By contrast, large-scale epigenetic alterations-which are tissue- and cancer-type specific-are not similarly constrained6 and therefore potentially have greater ability to detect and classify cancers in patients with early-stage disease. Here we develop a sensitive, immunoprecipitation-based protocol to analyse the methylome of small quantities of circulating cell-free DNA, and demonstrate the ability to detect large-scale DNA methylation changes that are enriched for tumour-specific patterns. We also demonstrate robust performance in cancer detection and classification across an extensive collection of plasma samples from several tumour types. This work sets the stage to establish biomarkers for the minimally invasive detection, interception and classification of early-stage cancers based on plasma cell-free DNA methylation patterns.
Assuntos
Ácidos Nucleicos Livres/sangue , Ácidos Nucleicos Livres/metabolismo , Metilação de DNA , DNA de Neoplasias/sangue , DNA de Neoplasias/metabolismo , Detecção Precoce de Câncer/métodos , Neoplasias/classificação , Neoplasias/genética , Adenocarcinoma/sangue , Adenocarcinoma/genética , Animais , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Neoplasias Colorretais/sangue , Neoplasias Colorretais/genética , Análise Mutacional de DNA , Epigênese Genética , Feminino , Xenoenxertos , Humanos , Biópsia Líquida , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Transplante de Neoplasias , Neoplasias/sangue , Especificidade de Órgãos , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/genéticaRESUMO
Despite advances that have improved the treatment of chronic myeloid leukemia (CML) patients in chronic phase, the mechanisms of the transition from chronic phase CML to blast crisis (BC) are not fully understood. Considering the key role of miR-15/16 loci in the pathogenesis of myeloid and lymphocytic leukemia, here we aimed to correlate the expression of miR-15a/16 and miR-15b/16 to progression of CML from chronic phase to BC. We analyzed the expression of the two miR-15/16 clusters in 17 CML patients in chronic phase and 22 patients in BC and in 11 paired chronic phase and BC CML patients. BC CMLs show a significant reduction of the expression of miR-15a/-15b/16 compared to CMLs in chronic phase. Moreover, BC CMLs showed an overexpression of miR-15/16 direct targets such as Bmi-1, ROR1, and Bcl-2 compared to CMLs in chronic phase. This study highlights the loss of both miR-15/16 clusters as a potential oncogenic driver in the transition from chronic phase to BC in CML patients.
Assuntos
Crise Blástica/patologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , MicroRNAs/genética , Adulto , Crise Blástica/genética , Progressão da Doença , Feminino , Regulação Leucêmica da Expressão Gênica , Loci Gênicos , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Masculino , Pessoa de Meia-Idade , Complexo Repressor Polycomb 1/genética , Complexo Repressor Polycomb 1/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase/genética , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase/metabolismoRESUMO
Acute myeloid leukemia (AML) is an aggressive blood cancer. With low survival rates, new drug targets are needed to improve treatment regimens and patient outcomes. Pseudolaric acid B (PAB) is a plant-derived bioactive compound predicted to interact with cluster of differentiation 147 (CD147/BSG). CD147 is a transmembrane glycoprotein overexpressed in various malignancies with suggested roles in regulating cancer cell survival, proliferation, invasion, and apoptosis. However, the detailed function of PAB in AML remains unknown. In this study, AML cell lines and patient-derived cells were used to show that PAB selectively targeted AML (IC50: 1.59 ± 0.47 µM). Moreover, proliferation assays, flow cytometry, and immunoblotting confirmed that PAB targeting of CD147 resulted in AML cell apoptosis. Indeed, the genetic silencing of CD147 significantly suppressed AML cell growth and attenuated PAB activity. Overall, PAB imparts anti-AML activity through transmembrane glycoprotein CD147.
Assuntos
Apoptose , Basigina , Proliferação de Células , Diterpenos , Leucemia Mieloide Aguda , Humanos , Basigina/metabolismo , Basigina/genética , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Proliferação de Células/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Diterpenos/farmacologia , Sobrevivência Celular/efeitos dos fármacosRESUMO
Venous thromboembolism (VTE) is a well-known complication in patients with acute lymphoblastic leukaemia (ALL) receiving asparaginase (ASP)-based chemotherapy, including the ASP-intensive Dana-Farber Cancer Institute (DFCI) 91-01 protocol for adults. Since 2019, native L-ASP is no longer available in Canada and was replaced by pegylated (PEG)-ASP. To determine whether the incidence of VTE has changed since switching from L-ASP to PEG-ASP, we conducted a single-centred retrospective cohort study. We included 245 adult patients with Philadelphia chromosome negative ALL between 2011 and 2021, with 175 from the L-ASP group (2011-2019) and 70 from the PEG-ASP group (2018-2021). During Induction, 10.29% (18/175) of patients who received L-ASP developed VTE, whereas 28.57% (20/70) of patients who received PEG-ASP developed VTE (p = 0.0035; odds ratio [OR] 3.35, 95% confidence interval [CI] 1.51-7.39), after adjusting for line type, gender, history of VTE, platelets at diagnosis. Similarly, during Intensification, 13.64% (18/132) of patients had VTE on L-ASP while 34.37% (11/32) of patients on PEG-ASP developed VTE (p = 0.0096; OR 3.96, 95% CI 1.57-9.96 with multivariable analysis). We found that PEG-ASP is associated with a higher incidence of VTE compared to L-ASP, both during Induction and Intensification, despite the administration of prophylactic anticoagulation. Further VTE mitigation strategies are needed in particular for adult patients with ALL receiving PEG-ASP.
Assuntos
Antineoplásicos , Leucemia-Linfoma Linfoblástico de Células Precursoras , Tromboembolia Venosa , Humanos , Adulto , Asparaginase/efeitos adversos , Estudos Retrospectivos , Tromboembolia Venosa/induzido quimicamente , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/complicações , Incidência , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Polietilenoglicóis/efeitos adversos , Antineoplásicos/uso terapêuticoRESUMO
MOTIVATION: Single-molecule molecular inversion probes (smMIPs) provide an exceptionally cost-effective and modular approach for routine or large-cohort next-generation sequencing. However, processing the derived raw data to generate highly accurate variants calls remains challenging. RESULTS: We introduce SmMIP-tools, a comprehensive computational method that promotes the detection of single nucleotide variants and short insertions and deletions from smMIP-based sequencing. Our approach delivered near-perfect performance when benchmarked against a set of known mutations in controlled experiments involving DNA dilutions and outperformed other commonly used computational methods for mutation detection. Comparison against clinically approved diagnostic testing of leukaemia patients demonstrated the ability to detect both previously reported variants and a set of pathogenic mutations that did not pass detection by clinical testing. Collectively, our results indicate that increased performance can be achieved when tailoring data processing and analysis to its related technology. The feasibility of using our method in research and clinical settings to benefit from low-cost smMIP technology is demonstrated. AVAILABILITY AND IMPLEMENTATION: The source code for SmMIP-tools, its manual and additional scripts aimed to foster large-scale data processing and analysis are all available on github (https://github.com/abelson-lab/smMIP-tools). Raw sequencing data generated in this study have been submitted to the European Genome-Phenome Archive (EGA; https://ega-archive.org) and can be accessed under accession number EGAS00001005359. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.
Assuntos
Genoma , Leucemia , Humanos , Mutação , Software , Sequenciamento de Nucleotídeos em Larga Escala/métodosRESUMO
Acute myeloid leukemia (AML) remains a devastating disease in need of new therapies to improve patient survival. Targeted adoptive T-cell therapies have achieved impressive clinical outcomes in some B-cell leukemias and lymphomas but not in AML. Double-negative T cells (DNTs) effectively kill blast cells from the majority of AML patients and are now being tested in clinical trials. However, AML blasts obtained from â¼30% of patients show resistance to DNT-mediated cytotoxicity; the markers or mechanisms underlying this resistance have not been elucidated. Here, we used a targeted clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) screen to identify genes that cause susceptibility of AML cells to DNT therapy. Inactivation of the Spt-Ada-Gcn5-acetyltransferase (SAGA) deubiquitinating complex components sensitized AML cells to DNT-mediated cytotoxicity. In contrast, CD64 inactivation resulted in resistance to DNT-mediated cytotoxicity. Importantly, the level of CD64 expression correlated strongly with the sensitivity of AML cells to DNT treatment. Furthermore, the ectopic expression of CD64 overcame AML resistance to DNTs in vitro and in vivo. Altogether, our data demonstrate the utility of CRISPR/Cas9 screens to uncover mechanisms underlying the sensitivity to DNT therapy and suggest CD64 as a predictive marker for response in AML patients.
Assuntos
Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Linfócitos T/transplante , Transferência Adotiva , Animais , Sistemas CRISPR-Cas , Células Cultivadas , Feminino , Regulação Leucêmica da Expressão Gênica , Humanos , Camundongos Endogâmicos NOD , Receptores de IgG/genéticaRESUMO
Venetoclax, a Bcl-2 inhibitor, in combination with the hypomethylating agent azacytidine, achieves complete remission with or without count recovery in â¼70% of treatment-naive elderly patients unfit for conventional intensive chemotherapy. However, the mechanism of action of this drug combination is not fully understood. We discovered that venetoclax directly activated T cells to increase their cytotoxicity against acute myeloid leukemia (AML) in vitro and in vivo. Venetoclax enhanced T-cell effector function by increasing reactive oxygen species generation through inhibition of respiratory chain supercomplexes formation. In addition, azacytidine induced a viral mimicry response in AML cells by activating the STING/cGAS pathway, thereby rendering the AML cells more susceptible to T cell-mediated cytotoxicity. Similar findings were seen in patients treated with venetoclax, as this treatment increased reactive oxygen species generation and activated T cells. Collectively, this study presents a new immune-mediated mechanism of action for venetoclax and azacytidine in the treatment of AML and highlights a potential combination of venetoclax and adoptive cell therapy for patients with AML.
Assuntos
Antineoplásicos/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Leucemia Mieloide Aguda/tratamento farmacológico , Sulfonamidas/farmacologia , Linfócitos T/efeitos dos fármacos , Adulto , Antineoplásicos/uso terapêutico , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Células Cultivadas , Humanos , Imunidade Celular/efeitos dos fármacos , Leucemia Mieloide Aguda/imunologia , Espécies Reativas de Oxigênio/imunologia , Sulfonamidas/uso terapêutico , Linfócitos T/imunologia , Células Tumorais CultivadasRESUMO
Acute myeloid leukemia (AML) cells have an atypical metabolic phenotype characterized by increased mitochondrial mass, as well as a greater reliance on oxidative phosphorylation and fatty acid oxidation (FAO) for survival. To exploit this altered metabolism, we assessed publicly available databases to identify FAO enzyme overexpression. Very long chain acyl-CoA dehydrogenase (VLCAD; ACADVL) was found to be overexpressed and critical to leukemia cell mitochondrial metabolism. Genetic attenuation or pharmacological inhibition of VLCAD hindered mitochondrial respiration and FAO contribution to the tricarboxylic acid cycle, resulting in decreased viability, proliferation, clonogenic growth, and AML cell engraftment. Suppression of FAO at VLCAD triggered an increase in pyruvate dehydrogenase activity that was insufficient to increase glycolysis but resulted in adenosine triphosphate depletion and AML cell death, with no effect on normal hematopoietic cells. Together, these results demonstrate the importance of VLCAD in AML cell biology and highlight a novel metabolic vulnerability for this devastating disease.
Assuntos
Ácidos Graxos/metabolismo , Leucemia Mieloide Aguda/metabolismo , Acil-CoA Desidrogenase de Cadeia Longa/genética , Acil-CoA Desidrogenase de Cadeia Longa/metabolismo , Linhagem Celular Tumoral , Ciclo do Ácido Cítrico , Ácidos Graxos/genética , Glicólise , Humanos , Cetona Oxirredutases/metabolismo , Leucemia Mieloide Aguda/genética , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismoRESUMO
A number of clinically validated drugs have been developed by repurposing the CUL4-DDB1-CRBN-RBX1 (CRL4CRBN) E3 ubiquitin ligase complex with molecular glue degraders to eliminate disease-driving proteins. Here, we present the identification of a first-in-class GSPT1-selective cereblon E3 ligase modulator, CC-90009. Biochemical, structural, and molecular characterization demonstrates that CC-90009 coopts the CRL4CRBN to selectively target GSPT1 for ubiquitination and proteasomal degradation. Depletion of GSPT1 by CC-90009 rapidly induces acute myeloid leukemia (AML) apoptosis, reducing leukemia engraftment and leukemia stem cells (LSCs) in large-scale primary patient xenografting of 35 independent AML samples, including those with adverse risk features. Using a genome-wide CRISPR-Cas9 screen for effectors of CC-90009 response, we uncovered the ILF2 and ILF3 heterodimeric complex as a novel regulator of cereblon expression. Knockout of ILF2/ILF3 decreases the production of full-length cereblon protein via modulating CRBN messenger RNA alternative splicing, leading to diminished response to CC-90009. The screen also revealed that the mTOR signaling and the integrated stress response specifically regulate the response to CC-90009 in contrast to other cereblon modulators. Hyperactivation of the mTOR pathway by inactivation of TSC1 and TSC2 protected against the growth inhibitory effect of CC-90009 by reducing CC-90009-induced binding of GSPT1 to cereblon and subsequent GSPT1 degradation. On the other hand, GSPT1 degradation promoted the activation of the GCN1/GCN2/ATF4 pathway and subsequent apoptosis in AML cells. Collectively, CC-90009 activity is mediated by multiple layers of signaling networks and pathways within AML blasts and LSCs, whose elucidation gives insight into further assessment of CC-90009s clinical utility. These trials were registered at www.clinicaltrials.gov as #NCT02848001 and #NCT04336982).
Assuntos
Acetamidas/farmacologia , Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Isoindóis/farmacologia , Leucemia Mieloide Aguda/patologia , Terapia de Alvo Molecular , Proteínas de Neoplasias/antagonistas & inibidores , Células-Tronco Neoplásicas/efeitos dos fármacos , Piperidonas/farmacologia , Ubiquitina-Proteína Ligases/antagonistas & inibidores , Acetamidas/uso terapêutico , Animais , Sistemas CRISPR-Cas , Linhagem Celular Tumoral , Humanos , Isoindóis/uso terapêutico , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Modelos Moleculares , Células-Tronco Neoplásicas/enzimologia , Proteína do Fator Nuclear 45/fisiologia , Proteínas do Fator Nuclear 90/fisiologia , Fatores de Terminação de Peptídeos/metabolismo , Piperidonas/uso terapêutico , Complexo de Endopeptidases do Proteassoma/metabolismo , Conformação Proteica , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteólise , Bibliotecas de Moléculas Pequenas , Estresse Fisiológico , Serina-Treonina Quinases TOR/fisiologia , Células U937 , Ubiquitinação/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Outcomes for patients with acute myeloid leukemia (AML) remain poor due to the inability of current therapeutic regimens to fully eradicate disease-initiating leukemia stem cells (LSC). Previous studies have demonstrated that oxidative phosphorylation (OXPHOS) is an essential process that is targetable in LSC. Sirtuin 3 (SIRT3), a mitochondrial deacetylase with a multi-faceted role in metabolic regulation, has been shown to regulate OXPHOS in cancer models; however, it has not yet been studied in the context of LSC. Thus, we sought to identify if SIRT3 is important for LSC function. Using RNAi and a SIRT3 inhibitor (YC8-02), we demonstrate that SIRT3 is a critical target for the survival of primary human LSC but is not essential for normal human hematopoietic stem and progenitor cell function. In order to elucidate the molecular mechanisms by which SIRT3 is essential in LSC we combined transcriptomic, proteomic, and lipidomic approaches, showing that SIRT3 is important for LSC function through the regulation of fatty acid oxidation (FAO) which is required to support OXPHOS and ATP production in human LSC. Further, we discovered two approaches to further sensitize LSC to SIRT3 inhibition. First, we found that LSC tolerate the toxic effects of fatty acid accumulation induced by SIRT3 inhibition by upregulating cholesterol esterification. Disruption of cholesterol homeostasis sensitizes LSC to YC8-02 and potentiates LSC death. Second, SIRT3 inhibition sensitizes LSC to the BCL-2 inhibitor venetoclax. Together, these findings establish SIRT3 as a regulator of lipid metabolism and potential therapeutic target in primitive AML cells.
Assuntos
Leucemia Mieloide Aguda , Sirtuína 3 , Humanos , Sirtuína 3/genética , Sirtuína 3/metabolismo , Sirtuína 3/farmacologia , Proteômica , Células-Tronco Neoplásicas/metabolismo , Metabolismo dos Lipídeos , Homeostase , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Ácidos Graxos/metabolismo , Ácidos Graxos/farmacologia , Ácidos Graxos/uso terapêutico , ColesterolRESUMO
Patients with hematological malignancies (HM) are at risk of acute respiratory failure (ARF). Malnutrition, a common association with HM, has the potential to influence ICU outcomes. Geriatric nutritional risk index (G-NRI) is a score derived from albumin and weight, which reflects risk of protein-energy malnutrition. We evaluated the association between G-NRI at ICU admission and ICU mortality in HM patients with ARF. We conducted a single center retrospective study of ventilated HM patients between 2014 and 2018. We calculated G-NRI for all patients using their ICU admission albumin and weight. Our primary outcome was ICU mortality. Secondary outcomes included duration of mechanical ventilation and ICU length of stay. Two hundred eighty patients were admitted to the ICU requiring ventilation. Median age was 62 years (IQR 51-68), 42% (n = 118) were females, and median SOFA score was 11 (IQR 9-14). The most common type of HM was acute leukemia (54%) and 40% underwent hematopoietic cell transplant. Median G-NRI was 87 (IQR 79-99). ICU mortality was 51% (n = 143) with a median duration of ventilation of 4 days (IQR 2-7). Mortality across those at severe malnutrition (NRI < 83.5) was 59% (65/111) compared to 46% (76/164) across those with moderate-no risk (p = 0.047). On multivariable analysis, severe NRI (OR 2.34, 95% CI 1.04-5.27, p = 0.04) was significantly associated with ICU mortality. In this single center, exploratory study, severe G-NRI was prognostic of ICU mortality in HM patients admitted with respiratory failure.
Assuntos
Neoplasias Hematológicas , Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Desnutrição , Síndrome do Desconforto Respiratório , Insuficiência Respiratória , Feminino , Humanos , Idoso , Pessoa de Meia-Idade , Masculino , Estudos Retrospectivos , Desnutrição/complicações , Insuficiência Respiratória/etiologia , Insuficiência Respiratória/terapia , Leucemia Mieloide Aguda/complicações , Unidades de Terapia IntensivaRESUMO
BACKGROUND: Inconclusive cytogenetic analysis (IC) at baseline has been reported as a predictor of poor prognosis in patients with acute myeloid leukemia (AML). The mutational profile in this group of patients, and its impact on outcomes have not been reported. METHODS: We retrospectively analyzed adult patients (≥18 years) with newly diagnosed AML treated with intensive induction chemotherapy between 2015 and 2019. Patients with any documented cytogenetic abnormalities were excluded. Targeted next generation sequencing (NGS) was performed in all patients. Baseline characteristics, mutation profile, and outcomes were compared between patients with normal cytogenetics(NC) and those with IC. RESULTS: Sixty-one patients (males 39.3%; median age 59 years) had IC at diagnosis. The proportion of patients with mutations in genes with proven prognostic impact were not different between AML patients with IC and NC. AML patients with NC were more likely to harbor the prognostically favorable NPM1mut /FLT3-ITDwt mutational combination conferring "favorable" risk status. As a result, a larger proportion of patients in the IC group underwent allogeneic hematopoietic stem cell transplantation (allo HCT; 54.1% vs. 39.6%; p = .02). The 2-year RFS (55.9% vs. 58.5%; p = .29) and OS (61.9% vs. 66.9%; p = .48) were similar in IC and NC patients. There was no difference in survival of patients who underwent allo HCT when compared with patients who did not (p = .99). CONCLUSIONS: Inconclusive cytogenetic analysis may not be an independent prognostic indicator in AML. In such patients, molecular abnormalities detected through NGS or whole genome sequencing are more likely to be informative.
Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Masculino , Humanos , Adulto , Pessoa de Meia-Idade , Estudos Retrospectivos , Nucleofosmina , Mutação , Prognóstico , Análise Citogenética , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Tirosina Quinase 3 Semelhante a fms/genéticaRESUMO
In acute myeloid leukaemia, long-term survival is poor as most patients relapse despite achieving remission. Historically, the failure of therapy has been thought to be due to mutations that produce drug resistance, possibly arising as a consequence of the mutagenic properties of chemotherapy drugs. However, other lines of evidence have pointed to the pre-existence of drug-resistant cells. For example, deep sequencing of paired diagnosis and relapse acute myeloid leukaemia samples has provided direct evidence that relapse in some cases is generated from minor genetic subclones present at diagnosis that survive chemotherapy, suggesting that resistant cells are generated by evolutionary processes before treatment and are selected by therapy. Nevertheless, the mechanisms of therapy failure and capacity for leukaemic regeneration remain obscure, as sequence analysis alone does not provide insight into the cell types that are fated to drive relapse. Although leukaemia stem cells have been linked to relapse owing to their dormancy and self-renewal properties, and leukaemia stem cell gene expression signatures are highly predictive of therapy failure, experimental studies have been primarily correlative and a role for leukaemia stem cells in acute myeloid leukaemia relapse has not been directly proved. Here, through combined genetic and functional analysis of purified subpopulations and xenografts from paired diagnosis/relapse samples, we identify therapy-resistant cells already present at diagnosis and two major patterns of relapse. In some cases, relapse originated from rare leukaemia stem cells with a haematopoietic stem/progenitor cell phenotype, while in other instances relapse developed from larger subclones of immunophenotypically committed leukaemia cells that retained strong stemness transcriptional signatures. The identification of distinct patterns of relapse should lead to improved methods for disease management and monitoring in acute myeloid leukaemia. Moreover, the shared functional and transcriptional stemness properties that underlie both cellular origins of relapse emphasize the importance of developing new therapeutic approaches that target stemness to prevent relapse.
Assuntos
Linhagem da Célula , Leucemia Mieloide Aguda/patologia , Recidiva Local de Neoplasia/patologia , Células-Tronco Neoplásicas/patologia , Animais , Células Clonais/metabolismo , Células Clonais/patologia , Feminino , Humanos , Imunofenotipagem , Leucemia Mieloide Aguda/genética , Camundongos , Mutação , Células Progenitoras Mieloides/metabolismo , Células Progenitoras Mieloides/patologia , Recidiva Local de Neoplasia/genética , Células-Tronco Neoplásicas/metabolismoRESUMO
Double knockout of the two miR-15/16 loci in mouse resulted in the development of acute myeloid leukemia (AML). This result suggested that, at least, a fraction of human AMLs could be due to a similar mechanism. We analyzed the role of the two miR-15/16 clusters in 93 myelodysplastic syndrome (MDS) patients divided in three subgroups: patients with MDS, patients with MDS before transforming into AML (MDS-T), and patients with AML evolving from MDS (MDS-AML). Then, we tested 139 AML cases and 14 different AML cell lines by assessing microRNA (miRNA) expression, target protein expression, genetic loss, and silencing. MDS-T and MDS-AML patients show a reduction of the expression of miR-15a/-15b/-16 compared to MDS patients. Each miRNA can significantly predict MDS and MDS-T groups. Then, 79% of primary AMLs show a reduced expression of miR-15a and/or miR-15b. The expression of miR-15a/-15b/-16 significantly stratified AML patients in two prognostic classes. Furthermore, 40% of AML cell lines showed a combined loss of the expression of miR-15a/-15b and overexpression of their direct/indirect targets. As potential mechanisms involved in the silencing of the two miR-15/16 loci, we identified a genetic loss of miR-15a and miR-15b and silencing of these two loci by methylation. We identified a potential driver oncogenic role in the loss of expression of both miR-15/16 clusters in the progression of MDS into AML and in AML pathogenesis. The stratification of AML patients, based on miR-15/16 expression, can lead to targeted and combination therapies for the treatment of this incurable disease.
Assuntos
Leucemia Mieloide Aguda/genética , MicroRNAs/genética , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Progressão da Doença , Feminino , Regulação Leucêmica da Expressão Gênica , Humanos , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-IdadeRESUMO
Through a clustered regularly insterspaced short palindromic repeats (CRISPR) screen to identify mitochondrial genes necessary for the growth of acute myeloid leukemia (AML) cells, we identified the mitochondrial outer membrane protein mitochondrial carrier homolog 2 (MTCH2). In AML, knockdown of MTCH2 decreased growth, reduced engraftment potential of stem cells, and induced differentiation. Inhibiting MTCH2 in AML cells increased nuclear pyruvate and pyruvate dehydrogenase (PDH), which induced histone acetylation and subsequently promoted the differentiation of AML cells. Thus, we have defined a new mechanism by which mitochondria and metabolism regulate AML stem cells and gene expression.