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1.
Mol Ther ; 32(6): 1628-1642, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38556793

RESUMO

Severe congenital neutropenia (CN) is an inherited pre-leukemia bone marrow failure syndrome commonly caused by autosomal-dominant ELANE mutations (ELANE-CN). ELANE-CN patients are treated with daily injections of recombinant human granulocyte colony-stimulating factor (rhG-CSF). However, some patients do not respond to rhG-CSF, and approximately 15% of ELANE-CN patients develop myelodysplasia or acute myeloid leukemia. Here, we report the development of a curative therapy for ELANE-CN through inhibition of ELANE mRNA expression by introducing two single-strand DNA breaks at the opposing DNA strands of the ELANE promoter TATA box using CRISPR-Cas9D10A nickases-termed MILESTONE. This editing effectively restored defective neutrophil differentiation of ELANE-CN CD34+ hematopoietic stem and progenitor cells (HSPCs) in vitro and in vivo, without affecting the functions of the edited neutrophils. CRISPResso analysis of the edited ELANE-CN CD34+ HSPCs revealed on-target efficiencies of over 90%. Simultaneously, GUIDE-seq, CAST-Seq, and rhAmpSeq indicated a safe off-target profile with no off-target sites or chromosomal translocations. Taken together, ex vivo gene editing of ELANE-CN HSPCs using MILESTONE in the setting of autologous stem cell transplantation could be a universal, safe, and efficient gene therapy approach for ELANE-CN patients.


Assuntos
Sistemas CRISPR-Cas , Síndrome Congênita de Insuficiência da Medula Óssea , Edição de Genes , Terapia Genética , Elastase de Leucócito , Neutropenia , Regiões Promotoras Genéticas , Edição de Genes/métodos , Humanos , Neutropenia/congênito , Neutropenia/terapia , Neutropenia/genética , Terapia Genética/métodos , Síndrome Congênita de Insuficiência da Medula Óssea/terapia , Síndrome Congênita de Insuficiência da Medula Óssea/genética , Elastase de Leucócito/genética , Elastase de Leucócito/metabolismo , Animais , Camundongos , Neutrófilos/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Mutação , Modelos Animais de Doenças , Fator Estimulador de Colônias de Granulócitos/genética , Doenças Genéticas Ligadas ao Cromossomo X/terapia , Doenças Genéticas Ligadas ao Cromossomo X/genética
2.
Blood ; 139(7): 1080-1097, 2022 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-34695195

RESUMO

In an effort to identify novel drugs targeting fusion-oncogene-induced acute myeloid leukemia (AML), we performed high-resolution proteomic analysis. In AML1-ETO (AE)-driven AML, we uncovered a deregulation of phospholipase C (PLC) signaling. We identified PLCgamma 1 (PLCG1) as a specific target of the AE fusion protein that is induced after AE binding to intergenic regulatory DNA elements. Genetic inactivation of PLCG1 in murine and human AML inhibited AML1-ETO dependent self-renewal programs, leukemic proliferation, and leukemia maintenance in vivo. In contrast, PLCG1 was dispensable for normal hematopoietic stem and progenitor cell function. These findings are extended to and confirmed by pharmacologic perturbation of Ca++-signaling in AML1-ETO AML cells, indicating that the PLCG1 pathway poses an important therapeutic target for AML1-ETO+ leukemic stem cells.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Regulação Leucêmica da Expressão Gênica , Células-Tronco Hematopoéticas/patologia , Leucemia Mieloide Aguda/patologia , Células-Tronco Neoplásicas/patologia , Proteínas de Fusão Oncogênica/metabolismo , Fosfolipase C gama/metabolismo , Proteína 1 Parceira de Translocação de RUNX1/metabolismo , Animais , Autorrenovação Celular , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Células-Tronco Hematopoéticas/metabolismo , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Camundongos , Células-Tronco Neoplásicas/metabolismo , Proteínas de Fusão Oncogênica/genética , Fosfolipase C gama/genética , Proteoma , Proteína 1 Parceira de Translocação de RUNX1/genética , Transcriptoma , Translocação Genética
3.
Cell Rep Med ; 3(8): 100724, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35977470

RESUMO

Most studies on leukemia focus on leukemia cells as isolated objects without considering the bone marrow niche. Pal et al. have recreated the bone marrow niche using induced pluripotent stem cells (iPSCs), identifying CDH2 as a therapeutically druggable leukemia-promoting factor.1.


Assuntos
Medula Óssea , Leucemia , Humanos , Medicina Regenerativa
4.
Cell Stem Cell ; 28(5): 906-922.e6, 2021 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-33894142

RESUMO

Severe congenital neutropenia (CN) is a pre-leukemic bone marrow failure syndrome that can evolve to acute myeloid leukemia (AML). Mutations in CSF3R and RUNX1 are frequently observed in CN patients, although how they drive the transition from CN to AML (CN/AML) is unclear. Here we establish a model of stepwise leukemogenesis in CN/AML using CRISPR-Cas9 gene editing of CN patient-derived iPSCs. We identified BAALC upregulation and resultant phosphorylation of MK2a as a key leukemogenic event. BAALC deletion or treatment with CMPD1, a selective inhibitor of MK2a phosphorylation, blocked proliferation and induced differentiation of primary CN/AML blasts and CN/AML iPSC-derived hematopoietic stem and progenitor cells (HSPCs) without affecting healthy donor or CN iPSC-derived HSPCs. Beyond detailing a useful method for future investigation of stepwise leukemogenesis, this study suggests that targeting BAALC and/or MK2a phosphorylation may prevent leukemogenic transformation or eliminate AML blasts in CN/AML and RUNX1 mutant BAALC(hi) de novo AML.


Assuntos
Células-Tronco Pluripotentes Induzidas , Leucemia Mieloide Aguda , Proteínas de Neoplasias , Neutropenia , Síndrome Congênita de Insuficiência da Medula Óssea , Humanos , Leucemia Mieloide Aguda/genética , Mutação/genética , Proteínas de Neoplasias/genética , Neutropenia/congênito , Neutropenia/genética , Oncogenes
5.
Nat Commun ; 10(1): 2891, 2019 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-31253791

RESUMO

Our ability to manage acute myeloid leukemia (AML) is limited by our incomplete understanding of the epigenetic disruption central to leukemogenesis, including improper histone methylation. Here we examine 16 histone H3 genes in 434 primary AML samples and identify Q69H, A26P, R2Q, R8H and K27M/I mutations (1.6%), with higher incidence in secondary AML (9%). These mutations occur in pre-leukemic hematopoietic stem cells (HSCs) and exist in the major leukemic clones in patients. They increase the frequency of functional HSCs, alter differentiation, and amplify leukemic aggressiveness. These effects are dependent on the specific mutation. H3K27 mutation increases the expression of genes involved in erythrocyte and myeloid differentiation with altered H3K27 tri-methylation and K27 acetylation. The functional impact of histone mutations is independent of RUNX1 mutation, although they at times co-occur. This study establishes that H3 mutations are drivers of human pre-cancerous stem cell expansion and important early events in leukemogenesis.


Assuntos
Epigenômica , Regulação Leucêmica da Expressão Gênica/fisiologia , Histonas/metabolismo , Leucemia Mieloide Aguda/metabolismo , Animais , Animais Geneticamente Modificados , Antineoplásicos/farmacologia , Sequência de Bases , Células da Medula Óssea , Diferenciação Celular , Transformação Celular Neoplásica , DNA/genética , Drosophila melanogaster/genética , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Hematopoese/fisiologia , Células-Tronco Hematopoéticas/metabolismo , Humanos , Camundongos , Mutação , Neoplasias Experimentais
7.
Clin Cancer Res ; 21(2): 240-8, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25593343

RESUMO

Acute myelogenous leukemia stem cells (AML-LSC) give rise to the leukemic bulk population and maintain disease. Relapse can arise from residual LSCs that have distinct sensitivity and dependencies when compared with the AML bulk. AML-LSCs are driven by genetic and epigenomic changes, and these alterations influence prognosis and clonal selection. Therapies targeting these molecular aberrations have been developed and show promising responses in advanced clinical trials; however, so far success with LSCs has been limited. Besides the genetic diversity, AML-LSCs are critically influenced by the microenvironment, and a third crucial aspect has recently come to the fore: A group of evolutionarily conserved signaling pathways such as canonical Wnt signaling, Notch signaling, or the Hedgehog pathway can be essential for maintenance of AML-LSC but may be redundant for normal hematopoietic stem cells. In addition, early reports suggest also regulators of cell polarity may also influence hematopoietic stem cells and AML biology. Interactions between these pathways have been investigated recently and suggest a network of signaling pathways involved in regulation of self-renewal and response to oncogenic stress. Here, we review how recent discoveries on regulation of AML-LSC-relevant evolutionarily conserved pathways may open opportunities for novel treatment approaches eradicating residual disease.


Assuntos
Leucemia Mieloide Aguda/genética , Transdução de Sinais , Animais , Evolução Molecular , Heterogeneidade Genética , Variação Genética , Humanos , Leucemia Mieloide Aguda/metabolismo , Mutação
8.
J Exp Med ; 210(1): 15-22, 2013 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-23277453

RESUMO

A unique characteristic of hematopoietic stem cells (HSCs) is the ability to self-renew. Several genes and signaling pathways control the fine balance between self-renewal and differentiation in HSCs and potentially also in leukemia stem cells. Recently, studies have shed light on developmental molecules and evolutionarily conserved signals as regulators of stem cells in hematopoiesis and leukemia. In this study, we provide evidence that the cell fate determinant Llgl1 (lethal giant larvae homolog 1) plays an important role in regulation of HSCs. Loss of Llgl1 leads to an increase in HSC numbers that show increased repopulation capacity and competitive advantage after transplantation. This advantage increases upon serial transplantation or when stress is applied to HSCs. Llgl1(-/-) HSCs show increased cycling but neither exhaust nor induce leukemia in recipient mice. Llgl1 inactivation is associated with transcriptional repression of transcription factors such as KLF4 (Krüppel-like factor 4) and EGR1 (early-growth-response 1) that are known inhibitors of HSC self-renewal. Decreased Llgl1 expression in human acute myeloid leukemia (AML) cells is associated with inferior patient survival. Thus, inactivation of Llgl1 enhances HSC self-renewal and fitness and is associated with unfavorable outcome in human AML.


Assuntos
Proteínas do Citoesqueleto/metabolismo , Células-Tronco Hematopoéticas/citologia , Leucemia Mieloide Aguda/patologia , Animais , Proteínas do Citoesqueleto/genética , Proteína 1 de Resposta de Crescimento Precoce/genética , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Regulação Leucêmica da Expressão Gênica , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/metabolismo , Humanos , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Prognóstico
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