Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 4.618
Filtrar
1.
Nat Commun ; 12(1): 1366, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33649320

RESUMO

Cancer stem cells drive disease progression and relapse in many types of cancer. Despite this, a thorough characterization of these cells remains elusive and with it the ability to eradicate cancer at its source. In acute myeloid leukemia (AML), leukemic stem cells (LSCs) underlie mortality but are difficult to isolate due to their low abundance and high similarity to healthy hematopoietic stem cells (HSCs). Here, we demonstrate that LSCs, HSCs, and pre-leukemic stem cells can be identified and molecularly profiled by combining single-cell transcriptomics with lineage tracing using both nuclear and mitochondrial somatic variants. While mutational status discriminates between healthy and cancerous cells, gene expression distinguishes stem cells and progenitor cell populations. Our approach enables the identification of LSC-specific gene expression programs and the characterization of differentiation blocks induced by leukemic mutations. Taken together, we demonstrate the power of single-cell multi-omic approaches in characterizing cancer stem cells.


Assuntos
Células Clonais/patologia , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Análise de Célula Única , Transcriptoma/genética , Biomarcadores Tumorais/genética , Medula Óssea/patologia , Diferenciação Celular , Regulação Leucêmica da Expressão Gênica , Genoma , Células-Tronco Hematopoéticas/patologia , Humanos , Células K562 , Mitocôndrias/genética , Mutação/genética
2.
Nat Commun ; 12(1): 821, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33547282

RESUMO

Down syndrome is associated with genome-wide perturbation of gene expression, which may be mediated by epigenetic changes. We perform an epigenome-wide association study on neonatal bloodspots comparing 196 newborns with Down syndrome and 439 newborns without Down syndrome, adjusting for cell-type heterogeneity, which identifies 652 epigenome-wide significant CpGs (P < 7.67 × 10-8) and 1,052 differentially methylated regions. Differential methylation at promoter/enhancer regions correlates with gene expression changes in Down syndrome versus non-Down syndrome fetal liver hematopoietic stem/progenitor cells (P < 0.0001). The top two differentially methylated regions overlap RUNX1 and FLI1, both important regulators of megakaryopoiesis and hematopoietic development, with significant hypermethylation at promoter regions of these two genes. Excluding Down syndrome newborns harboring preleukemic GATA1 mutations (N = 30), identified by targeted sequencing, has minimal impact on the epigenome-wide association study results. Down syndrome has profound, genome-wide effects on DNA methylation in hematopoietic cells in early life, which may contribute to the high frequency of hematological problems, including leukemia, in children with Down syndrome.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/genética , Síndrome de Down/genética , Epigênese Genética , Hematopoese/genética , Células-Tronco Hematopoéticas/metabolismo , Proteína Proto-Oncogênica c-fli-1/genética , Estudos de Casos e Controles , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Ilhas de CpG , Metilação de DNA , Síndrome de Down/metabolismo , Síndrome de Down/patologia , Feminino , Feto , Fator de Transcrição GATA1/genética , Fator de Transcrição GATA1/metabolismo , Genoma Humano , Estudo de Associação Genômica Ampla , Células-Tronco Hematopoéticas/patologia , Humanos , Recém-Nascido , Fígado/metabolismo , Fígado/patologia , Masculino , Regiões Promotoras Genéticas , Proteína Proto-Oncogênica c-fli-1/metabolismo
3.
Int J Mol Sci ; 22(2)2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33440869

RESUMO

Myeloproliferative neoplasms (MPNs) are unique hematopoietic stem cell disorders sharing mutations that constitutively activate the signal-transduction pathways involved in haematopoiesis. They are characterized by stem cell-derived clonal myeloproliferation. The key MPNs comprise chronic myeloid leukemia (CML), polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF). CML is defined by the presence of the Philadelphia (Ph) chromosome and BCR-ABL1 fusion gene. Despite effective cytoreductive agents and targeted therapy, complete CML/MPN stem cell eradication is rarely achieved. In this review article, we discuss the novel agents and combination therapy that can potentially abnormal hematopoietic stem cells in CML and MPNs and the CML/MPN stem cell-sustaining bone marrow microenvironment.


Assuntos
Suscetibilidade a Doenças , Células-Tronco Hematopoéticas/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/etiologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Transtornos Mieloproliferativos/etiologia , Transtornos Mieloproliferativos/terapia , Células-Tronco Neoplásicas/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Autofagia , Biomarcadores Tumorais , Sobrevivência Celular/efeitos dos fármacos , Transformação Celular Neoplásica/genética , Terapia Combinada , Predisposição Genética para Doença , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/patologia , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Terapia de Alvo Molecular , Transtornos Mieloproliferativos/patologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Cromossomo Filadélfia , Transdução de Sinais/efeitos dos fármacos , Nicho de Células-Tronco , Microambiente Tumoral
4.
Methods Mol Biol ; 2185: 51-63, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33165842

RESUMO

Flow cytometry has been widely used in basic and clinical research for analysis of a variety of normal and malignant cells. Hematopoietic stem cells (HSCs) and leukemic stem cells (LSCs) can be highly purified by flow cytometry. Isolated HSCs and LSCs can be functionally identified by transplantation assays and can also be studied at the molecular level. Here we describe the flow cytometry methods for analysis and isolation of mouse HSCs and LSCs.


Assuntos
Citometria de Fluxo , Células-Tronco Hematopoéticas , Leucemia , Células-Tronco Neoplásicas , Animais , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/patologia , Leucemia/metabolismo , Leucemia/patologia , Camundongos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia
5.
Methods Mol Biol ; 2185: 411-422, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33165864

RESUMO

Patient-derived induced pluripotent stem cells (iPSCs) have recently provided a new way to model acute myeloid leukemia (AML) and other myeloid malignancies. Here, we describe methods for the generation of patient-derived iPSCs from leukemia cells and for their subsequent directed in vitro differentiation into hematopoietic cells that recapitulate features of leukemia stem cells (LSCs) and leukemic blasts.


Assuntos
Reprogramação Celular , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Leucemia Mieloide Aguda/metabolismo , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Hematopoéticas/patologia , Humanos , Células-Tronco Pluripotentes Induzidas/patologia , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Células-Tronco Neoplásicas/patologia
6.
Mol Cell ; 81(3): 530-545.e5, 2021 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-33382982

RESUMO

Transcription factors regulate gene networks controlling normal hematopoiesis and are frequently deregulated in acute myeloid leukemia (AML). Critical to our understanding of the mechanism of cellular transformation by oncogenic transcription factors is the ability to define their direct gene targets. However, gene network cascades can change within minutes to hours, making it difficult to distinguish direct from secondary or compensatory transcriptional changes by traditional methodologies. To overcome this limitation, we devised cell models in which the AML1-ETO protein could be quickly degraded upon addition of a small molecule. The rapid kinetics of AML1-ETO removal, when combined with analysis of transcriptional output by nascent transcript analysis and genome-wide AML1-ETO binding by CUT&RUN, enabled the identification of direct gene targets that constitute a core AML1-ETO regulatory network. Moreover, derepression of this gene network was associated with RUNX1 DNA binding and triggered a transcription cascade ultimately resulting in myeloid differentiation.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Leucemia Mieloide Aguda/metabolismo , Células-Tronco Neoplásicas/metabolismo , Proteínas de Fusão Oncogênica/metabolismo , RNA Neoplásico/biossíntese , Proteína 1 Parceira de Translocação de RUNX1/metabolismo , Transcrição Genética , Acetilação , Sítios de Ligação , Ligação Competitiva , Diferenciação Celular , Linhagem Celular Tumoral , Proliferação de Células , Autorrenovação Celular , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Sangue Fetal/citologia , Regulação Leucêmica da Expressão Gênica , Redes Reguladoras de Genes , Células HEK293 , Células-Tronco Hematopoéticas/patologia , Histonas/metabolismo , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Células-Tronco Neoplásicas/patologia , Proteínas de Fusão Oncogênica/genética , Ligação Proteica , Proteólise , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , RNA Neoplásico/genética , Proteína 1 Parceira de Translocação de RUNX1/genética , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Fatores de Tempo , Transcriptoma
7.
Mol Med Rep ; 22(6): 4485-4491, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33173966

RESUMO

In December 2019, an emergence of pneumonia was detected in patients infected with a novel coronavirus (CoV) in Wuhan (Hubei, China). The International Committee on Taxonomy of Viruses named the virus severe acute respiratory syndrome­CoV­2 and the disease CoV disease­19 (COVID­19). Patients with COVID­19 present with symptoms associated with respiratory system dysfunction and hematological changes, including lymphopenia, thrombocytopenia and coagulation disorders. However, to the best of our knowledge, the pathogenesis of COVID­19 remains unclear. Therefore, understanding the mechanisms underlying the hematological changes that manifest during COVID­19 may aid in the development of treatments and may improve patient prognosis.


Assuntos
Betacoronavirus , Infecções por Coronavirus/sangue , Pneumonia Viral/sangue , Anticorpos Antivirais/imunologia , Complexo Antígeno-Anticorpo/imunologia , Antivirais/farmacologia , Antivirais/uso terapêutico , Betacoronavirus/imunologia , Microambiente Celular , Infecções por Coronavirus/complicações , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/terapia , Síndrome da Liberação de Citocina/sangue , Síndrome da Liberação de Citocina/etiologia , Síndrome da Liberação de Citocina/prevenção & controle , Citocinas/sangue , Testes Diagnósticos de Rotina , Endotélio Vascular/patologia , Testes Hematológicos , Hematopoese/efeitos dos fármacos , Células-Tronco Hematopoéticas/patologia , Humanos , Hipoalbuminemia/etiologia , Fígado/fisiopatologia , Pulmão/fisiopatologia , Linfopenia/etiologia , Linfopenia/fisiopatologia , Pandemias , Pneumonia Viral/complicações , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/terapia , Traumatismo por Reperfusão/etiologia , Trombocitopenia/etiologia , Trombocitopenia/fisiopatologia , Trombofilia/etiologia
8.
Ann Hematol ; 99(10): 2329-2338, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32821971

RESUMO

Patients with the pre-leukemia bone marrow failure syndrome called severe congenital neutropenia (CN) have an approximately 15% risk of developing acute myeloid leukemia (AML; called here CN/AML). Most CN/AML patients co-acquire CSF3R and RUNX1 mutations, which play cooperative roles in the development of AML. To establish an in vitro model of leukemogenesis, we utilized bone marrow lin- cells from transgenic C57BL/6-d715 Csf3r mice expressing a CN patient-mimicking truncated CSF3R mutation. We transduced these cells with vectors encoding RUNX1 wild type (WT) or RUNX1 mutant proteins carrying the R139G or R174L mutations. Cells transduced with these RUNX1 mutants showed diminished in vitro myeloid differentiation and elevated replating capacity, compared with those expressing WT RUNX1. mRNA expression analysis showed that cells transduced with the RUNX1 mutants exhibited hyperactivation of inflammatory signaling and innate immunity pathways, including IL-6, TLR, NF-kappaB, IFN, and TREM1 signaling. These data suggest that the expression of mutated RUNX1 in a CSF3R-mutated background may activate the pro-inflammatory cell state and inhibit myeloid differentiation.


Assuntos
Síndrome Congênita de Insuficiência da Medula Óssea/genética , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Células-Tronco Hematopoéticas/patologia , Células Mieloides/patologia , Mielopoese/genética , Neutropenia/congênito , Pré-Leucemia/genética , Receptores de Fator Estimulador de Colônias/genética , Animais , Divisão Celular , Ensaio de Unidades Formadoras de Colônias , Síndrome Congênita de Insuficiência da Medula Óssea/patologia , Subunidade alfa 2 de Fator de Ligação ao Core/fisiologia , Perfilação da Expressão Gênica , Imunidade Inata , Inflamação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neutropenia/genética , Neutropenia/patologia , Pré-Leucemia/patologia , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptores de Fator Estimulador de Colônias/fisiologia , Proteínas Recombinantes/genética , Organismos Livres de Patógenos Específicos
9.
Nat Commun ; 11(1): 3344, 2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32620751

RESUMO

Diamond Blackfan Anemia (DBA) is a congenital bone marrow failure syndrome associated with ribosomal gene mutations that lead to ribosomal insufficiency. DBA is characterized by anemia, congenital anomalies, and cancer predisposition. Treatment for DBA is associated with significant morbidity. Here, we report the identification of Nemo-like kinase (NLK) as a potential target for DBA therapy. To identify new DBA targets, we screen for small molecules that increase erythroid expansion in mouse models of DBA. This screen identified a compound that inhibits NLK. Chemical and genetic inhibition of NLK increases erythroid expansion in mouse and human progenitors, including bone marrow cells from DBA patients. In DBA models and patient samples, aberrant NLK activation is initiated at the Megakaryocyte/Erythroid Progenitor (MEP) stage of differentiation and is not observed in non-erythroid hematopoietic lineages or healthy erythroblasts. We propose that NLK mediates aberrant erythropoiesis in DBA and is a potential target for therapy.


Assuntos
Anemia de Diamond-Blackfan/patologia , Células-Tronco Hematopoéticas/patologia , Proteínas Serina-Treonina Quinases/metabolismo , Anemia de Diamond-Blackfan/dietoterapia , Anemia de Diamond-Blackfan/genética , Animais , Benzamidas/farmacologia , Benzamidas/uso terapêutico , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células , Células Cultivadas , Dioxóis/farmacologia , Dioxóis/uso terapêutico , Modelos Animais de Doenças , Eritropoese/efeitos dos fármacos , Eritropoese/genética , Humanos , Camundongos , Camundongos Transgênicos , Mutação , Cultura Primária de Células , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Pirazóis/farmacologia , Pirazóis/uso terapêutico , Quinolinas/farmacologia , Quinolinas/uso terapêutico , RNA Interferente Pequeno/metabolismo , Proteínas Ribossômicas/genética
10.
Adv Exp Med Biol ; 1207: 601-613, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32671778

RESUMO

Leukemia is a malignant clonal disease that originates from hematopoietic stem cells. As in-depth research examines the molecular biology and immunology of the hematopoietic system, leukemia treatment has evolved from a single cytotoxic drug to treatments that inducing differentiation and apoptosis. Meanwhile, autophagy has become a growing concern as a new form of cell death. The immune response, hematopoietic stem cell differentiation, and drug resistance of tumor cells are all potentially affected by autophagy. Regulating autophagy may become one of the promising directions in the field of targeted therapy.


Assuntos
Autofagia , Leucemia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Autofagia/efeitos dos fármacos , Células-Tronco Hematopoéticas/patologia , Humanos , Leucemia/tratamento farmacológico , Leucemia/patologia
11.
Nature ; 584(7819): 130-135, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32581364

RESUMO

The extent to which the biology of oncogenesis and ageing are shaped by factors that distinguish human populations is unknown. Haematopoietic clones with acquired mutations become common with advancing age and can lead to blood cancers1-10. Here we describe shared and population-specific patterns of genomic mutations and clonal selection in haematopoietic cells on the basis of 33,250 autosomal mosaic chromosomal alterations that we detected in 179,417 Japanese participants in the BioBank Japan cohort and compared with analogous data from the UK Biobank. In this long-lived Japanese population, mosaic chromosomal alterations were detected in more than 35.0% (s.e.m., 1.4%) of individuals older than 90 years, which suggests that such clones trend towards inevitability with advancing age. Japanese and European individuals exhibited key differences in the genomic locations of mutations in their respective haematopoietic clones; these differences predicted the relative rates of chronic lymphocytic leukaemia (which is more common among European individuals) and T cell leukaemia (which is more common among Japanese individuals) in these populations. Three different mutational precursors of chronic lymphocytic leukaemia (including trisomy 12, loss of chromosomes 13q and 13q, and copy-neutral loss of heterozygosity) were between two and six times less common among Japanese individuals, which suggests that the Japanese and European populations differ in selective pressures on clones long before the development of clinically apparent chronic lymphocytic leukaemia. Japanese and British populations also exhibited very different rates of clones that arose from B and T cell lineages, which predicted the relative rates of B and T cell cancers in these populations. We identified six previously undescribed loci at which inherited variants predispose to mosaic chromosomal alterations that duplicate or remove the inherited risk alleles, including large-effect rare variants at NBN, MRE11 and CTU2 (odds ratio, 28-91). We suggest that selective pressures on clones are modulated by factors that are specific to human populations. Further genomic characterization of clonal selection and cancer in populations from around the world is therefore warranted.


Assuntos
Envelhecimento/genética , Aberrações Cromossômicas , Cromossomos Humanos/genética , Células Clonais/metabolismo , Genoma Humano/genética , Células-Tronco Hematopoéticas/metabolismo , Mutação , Idoso de 80 Anos ou mais , Alelos , Linhagem da Célula , Células Clonais/citologia , Células Clonais/patologia , Estudos de Coortes , Feminino , Loci Gênicos/genética , Hematopoese/genética , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/patologia , Humanos , Japão , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/patologia , Leucemia de Células T/genética , Leucemia de Células T/patologia , Masculino , Mosaicismo , Reino Unido
12.
Ann Hematol ; 99(7): 1515-1523, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32506245

RESUMO

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening systemic hyperinflammatory disorder. We found recently that repeated lipopolysaccharide (LPS) treatment induces HLH-like features in senescence-accelerated mice (SAMP1/TA-1) but not in senescence-resistant control mice (SAMR1). In this study, we analyzed the dynamics of hematopoiesis in this mouse model of HLH. When treated repeatedly with LPS, the numbers of myeloid progenitor cells (CFU-GM) and B-lymphoid progenitor cells (CFU-preB) in the bone marrow (BM) rapidly decreased after each treatment in both strains. The number of CFU-GM in SAMP1/TA-1 and SAMR1, and of CFU-preB in SAMR1, returned to pretreatment levels by 7 days after each treatment. However, the recovery in the number of CFU-preB in SAMP1/TA-1 was limited. In both strains, the BM expression of genes encoding positive regulators of myelopoiesis (granulocyte colony-stimulating factor (G-CSF), granulocyte macrophage colony-stimulating factor (GM-CSF), and interleukin (IL)-6), and negative regulators of B lymphopoiesis (tumor necrosis factor (TNF)-α) was increased. The expression of genes encoding positive regulators of B lymphopoiesis (stromal-cell derived factor (SDF)-1, IL-7, and stem cell factor (SCF)) was persistently decreased in SAMP1/TA-1 but not in SAMR1. Expression of the gene encoding p16INK4a and the proportion of ß-galactosidase-positive cells were increased in cultured stromal cells obtained from LPS-treated SAMP1/TA-1 but not in those from LPS-treated SAMR1. LPS treatment induced qualitative changes in stromal cells, which comprise the microenvironment supporting appropriate hematopoiesis, in SAMP1/TA-1; these stromal cell changes are inferred to disrupt the dynamics of hematopoiesis. Thus, hematopoietic tissue is one of the organs that suffer life-threatening damage in HLH.


Assuntos
Medula Óssea/patologia , Hematopoese/fisiologia , Células-Tronco Hematopoéticas/patologia , Linfo-Histiocitose Hemofagocítica/patologia , Linfo-Histiocitose Hemofagocítica/fisiopatologia , Nicho de Células-Tronco/fisiologia , Animais , Células da Medula Óssea/patologia , Células da Medula Óssea/fisiologia , Contagem de Células , Células Cultivadas , Microambiente Celular/fisiologia , Modelos Animais de Doenças , Células-Tronco Hematopoéticas/fisiologia , Lipopolissacarídeos , Linfo-Histiocitose Hemofagocítica/induzido quimicamente , Masculino , Camundongos , Células Estromais/patologia
13.
Mol Cell ; 78(3): 477-492.e8, 2020 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-32386542

RESUMO

Myelofibrosis is a severe myeloproliferative neoplasm characterized by increased numbers of abnormal bone marrow megakaryocytes that induce fibrosis, destroying the hematopoietic microenvironment. To determine the cellular and molecular basis for aberrant megakaryopoiesis in myelofibrosis, we performed single-cell transcriptome profiling of 135,929 CD34+ lineage- hematopoietic stem and progenitor cells (HSPCs), single-cell proteomics, genomics, and functional assays. We identified a bias toward megakaryocyte differentiation apparent from early multipotent stem cells in myelofibrosis and associated aberrant molecular signatures. A sub-fraction of myelofibrosis megakaryocyte progenitors (MkPs) are transcriptionally similar to healthy-donor MkPs, but the majority are disease specific, with distinct populations expressing fibrosis- and proliferation-associated genes. Mutant-clone HSPCs have increased expression of megakaryocyte-associated genes compared to wild-type HSPCs, and we provide early validation of G6B as a potential immunotherapy target. Our study paves the way for selective targeting of the myelofibrosis clone and illustrates the power of single-cell multi-omics to discover tumor-specific therapeutic targets and mediators of tissue fibrosis.


Assuntos
Hematopoese/fisiologia , Megacariócitos/patologia , Mielofibrose Primária/sangue , Idoso , Idoso de 80 Anos ou mais , Diferenciação Celular , Feminino , Regulação da Expressão Gênica , Hematopoese/genética , Células-Tronco Hematopoéticas/patologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Megacariócitos/fisiologia , Pessoa de Meia-Idade , Mutação , Receptores Imunológicos/genética , Análise de Célula Única/métodos
14.
FASEB J ; 34(6): 7247-7252, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32427393

RESUMO

The medical, public health, and scientific communities are grappling with monumental imperatives to contain COVID-19, develop effective vaccines, identify efficacious treatments for the infection and its complications, and find biomarkers that detect patients at risk of severe disease. The focus of this communication is on a potential biomarker, short telomere length (TL), that might serve to identify patients more likely to die from the SARS-CoV-2 infection, regardless of age. The common thread linking these patients is lymphopenia, which largely reflects a decline in the numbers of CD4/CD8 T cells but not B cells. These findings are consistent with data that lymphocyte TL dynamics impose a limit on T-cell proliferation. They suggest that T-cell lymphopoiesis might stall in individuals with short TL who are infected with SARS-CoV-2.


Assuntos
Betacoronavirus , Infecções por Coronavirus/patologia , Linfopenia/etiologia , Modelos Biológicos , Pneumonia Viral/patologia , Subpopulações de Linfócitos T/ultraestrutura , Encurtamento do Telômero , Telômero/ultraestrutura , Biomarcadores , Medula Óssea/patologia , Divisão Celular , Infecções por Coronavirus/genética , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/mortalidade , Progressão da Doença , Células-Tronco Hematopoéticas/patologia , Humanos , Ativação Linfocitária , Contagem de Linfócitos , Linfopenia/patologia , Linfopoese , Pandemias , Pneumonia Viral/genética , Pneumonia Viral/imunologia , Pneumonia Viral/mortalidade , Prognóstico , Risco
15.
Vascular ; 28(5): 664-672, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32390561

RESUMO

BACKGROUND: The high rate of clinical failure of prosthetic arteriovenous grafts continues to suggest the need for novel tissue-engineered vascular grafts. We tested the hypothesis that the decellularized rat jugular vein could be successfully used as a conduit and that it would support reendothelialization as well as adaptation to the arterial environment. MATERIALS AND METHODS: Autologous (control) or heterologous decellularized jugular vein (1 cm length, 1 mm diameter) was sewn between the inferior vena cava and aorta as an arteriovenous graft in Wistar rats. Rats were sacrificed on postoperative day 21 for examination. RESULTS: All rats survived, and grafts had 100% patency in both the control and decellularized groups. Both control and decellularized jugular vein grafts showed similar rates of reendothelialization, smooth muscle cell deposition, macrophage infiltration, and cell turnover. The outflow veins distal to the grafts showed similar adaptation to the arteriovenous flow. Both CD34, CD90 and nestin positive cells, as well as M1-type and M2-type macrophages accumulated around the graft. CONCLUSIONS: This model shows that decellularized vein can be successfully used as an arteriovenous graft between the rat aorta and the inferior vena cava. Several types of cells, including progenitor cells and macrophages, are present in the host response to these grafts in this model. This model can be used to test the application of arteriovenous grafts before conducting large animal experiments.


Assuntos
Aorta/cirurgia , Derivação Arteriovenosa Cirúrgica , Veias Jugulares/transplante , Grau de Desobstrução Vascular , Veia Cava Inferior/cirurgia , Animais , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Células Progenitoras Endoteliais/metabolismo , Células Progenitoras Endoteliais/patologia , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/patologia , Veias Jugulares/metabolismo , Veias Jugulares/patologia , Veias Jugulares/fisiopatologia , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Ratos Wistar , Fatores de Tempo , Remodelação Vascular
16.
Nat Rev Cancer ; 20(7): 365-382, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32415283

RESUMO

Haematopoiesis is governed by haematopoietic stem cells (HSCs) that produce all lineages of blood and immune cells. The maintenance of blood homeostasis requires a dynamic response of HSCs to stress, and dysregulation of these adaptive-response mechanisms underlies the development of myeloid leukaemia. Leukaemogenesis often occurs in a stepwise manner, with genetic and epigenetic changes accumulating in pre-leukaemic HSCs prior to the emergence of leukaemic stem cells (LSCs) and the development of acute myeloid leukaemia. Clinical data have revealed the existence of age-related clonal haematopoiesis, or the asymptomatic clonal expansion of mutated blood cells in the elderly, and this phenomenon is connected to susceptibility to leukaemic transformation. Here we describe how selection for specific mutations that increase HSC competitive fitness, in conjunction with additional endogenous and environmental changes, drives leukaemic transformation. We review the ways in which LSCs take advantage of normal HSC properties to promote survival and expansion, thus underlying disease recurrence and resistance to conventional therapies, and we detail our current understanding of leukaemic 'stemness' regulation. Overall, we link the cellular and molecular mechanisms regulating HSC behaviour with the functional dysregulation of these mechanisms in myeloid leukaemia and discuss opportunities for targeting LSC-specific mechanisms for the prevention or cure of malignant diseases.


Assuntos
Carcinogênese/genética , Hematopoese/fisiologia , Células-Tronco Hematopoéticas/fisiologia , Leucemia Mieloide Aguda/fisiopatologia , Antineoplásicos/farmacologia , Carcinogênese/efeitos dos fármacos , Carcinogênese/patologia , Interação Gene-Ambiente , Instabilidade Genômica/efeitos dos fármacos , Instabilidade Genômica/fisiologia , Hematopoese/genética , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/patologia , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Mutação/efeitos dos fármacos , Mutação/genética , Mutação/fisiologia , Nicho de Células-Tronco/efeitos dos fármacos , Nicho de Células-Tronco/fisiologia , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/fisiologia
17.
PLoS One ; 15(5): e0233751, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32470079

RESUMO

Mesenchymal stromal cells are an important component of the bone marrow hematopoietic niche. Prior studies showed that signaling from members of the transforming growth factor (TGF) superfamily in mesenchymal stromal cells is required for normal niche development. Here, we assessed the impact of TGF family signaling on niche maintenance and stress responses by deleting Smad4 in mesenchymal stromal cells at birth, thereby abrogating canonical TGF signaling. No alteration in the number or spatial organization of CXCL12-abundant reticular (CAR) cells, osteoblasts, or adipocytes was observed in Osx-Cre, Smad4fl/fl mice, and expression of key niche factors was normal. Basal hematopoiesis and stress erythropoiesis responses to acute hemolytic anemia were normal. TGF-ß potently inhibits stromal CXCL12 expression in vitro; however, G-CSF induced decreases in bone marrow CXCL12 expression and subsequent hematopoietic stem/progenitor cell mobilization were normal in Osx-Cre, Tgfbr2fl/fl mice, in which all TGF-ß signaling in mesenchymal stromal is lost. Finally, although a prior study showed that TGF-ß enhances recovery from myeloablative therapy, hematopoietic recovery following single or multiple doses of 5-flurauracil were normal in Osx-Cre, Tgfbr2fl/fl mice. Collectively, these data suggest that TGF family member signaling in mesenchymal stromal cells is dispensable for hematopoietic niche maintenance under basal and stress conditions.


Assuntos
Anemia Hemolítica/metabolismo , Eritropoese , Células-Tronco Hematopoéticas , Células-Tronco Mesenquimais , Fator de Crescimento Transformador beta/fisiologia , Fatores de Crescimento Transformadores/fisiologia , Doença Aguda , Anemia Hemolítica/patologia , Animais , Medula Óssea/metabolismo , Medula Óssea/patologia , Células Cultivadas , Quimiocina CXCL12/metabolismo , Feminino , Fator Estimulador de Colônias de Granulócitos/farmacologia , Mobilização de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/patologia , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/patologia , Camundongos , Camundongos Endogâmicos C57BL , Nicho de Células-Tronco
18.
Nat Med ; 26(4): 535-541, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32284612

RESUMO

Base editing by nucleotide deaminases linked to programmable DNA-binding proteins represents a promising approach to permanently remedy blood disorders, although its application in engrafting hematopoietic stem cells (HSCs) remains unexplored. In this study, we purified A3A (N57Q)-BE3 base editor for ribonucleoprotein (RNP) electroporation of human-peripheral-blood-mobilized CD34+ hematopoietic stem and progenitor cells (HSPCs). We observed frequent on-target cytosine base edits at the BCL11A erythroid enhancer at +58 with few indels. Fetal hemoglobin (HbF) induction in erythroid progeny after base editing or nuclease editing was similar. A single therapeutic base edit of the BCL11A enhancer prevented sickling and ameliorated globin chain imbalance in erythroid progeny from sickle cell disease and ß-thalassemia patient-derived HSPCs, respectively. Moreover, efficient multiplex editing could be achieved with combined disruption of the BCL11A erythroid enhancer and correction of the HBB -28A>G promoter mutation. Finally, base edits could be produced in multilineage-repopulating self-renewing human HSCs with high frequency as assayed in primary and secondary recipient animals resulting in potent HbF induction in vivo. Together, these results demonstrate the potential of RNP base editing of human HSPCs as a feasible alternative to nuclease editing for HSC-targeted therapeutic genome modification.


Assuntos
Anemia Falciforme/patologia , Edição de Genes , Terapia Genética/métodos , Células-Tronco Hematopoéticas/metabolismo , Proteínas Repressoras/genética , gama-Globinas/genética , Anemia Falciforme/terapia , Animais , Antígenos CD34/metabolismo , Sistemas CRISPR-Cas , Células Cultivadas , Estudos de Viabilidade , Feminino , Edição de Genes/métodos , Marcação de Genes/métodos , Transplante de Células-Tronco Hematopoéticas/métodos , Células-Tronco Hematopoéticas/patologia , Xenoenxertos , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos Transgênicos , Cultura Primária de Células , Proteínas Repressoras/metabolismo , Talassemia beta/patologia , Talassemia beta/terapia , gama-Globinas/metabolismo
19.
Cancer Res ; 80(12): 2523-2536, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32341038

RESUMO

RUNX3, a RUNX family transcription factor, regulates normal hematopoiesis and functions as a tumor suppressor in various tumors in humans and mice. However, emerging studies have documented increased expression of RUNX3 in hematopoietic stem/progenitor cells (HSPC) of a subset of patients with myelodysplastic syndrome (MDS) showing a worse outcome, suggesting an oncogenic function for RUNX3 in the pathogenesis of hematologic malignancies. To elucidate the oncogenic function of RUNX3 in the pathogenesis of MDS in vivo, we generated a RUNX3-expressing, Tet2-deficient mouse model with the pancytopenia and dysplastic blood cells characteristic of MDS in patients. RUNX3-expressing cells markedly suppressed the expression levels of Runx1, a critical regulator of hemaotpoiesis in normal and malignant cells, as well as its target genes, which included crucial tumor suppressors such as Cebpa and Csf1r. RUNX3 bound these genes and remodeled their Runx1-binding regions in Tet2-deficient cells. Overexpression of RUNX3 inhibited the transcriptional function of Runx1 and compromised hematopoiesis to facilitate the development of MDS in the absence of Tet2, indicating that RUNX3 is an oncogene. Furthermore, overexpression of RUNX3 activated the transcription of Myc target genes and rendered cells sensitive to inhibition of Myc-Max heterodimerization. Collectively, these results reveal the mechanism by which RUNX3 overexpression exerts oncogenic effects on the cellular function of and transcriptional program in Tet2-deficient stem cells to drive the transformation of MDS. SIGNIFICANCE: This study defines the oncogenic effects of transcription factor RUNX3 in driving the transformation of myelodysplastic syndrome, highlighting RUNX3 as a potential target for therapeutic intervention.


Assuntos
Transformação Celular Neoplásica/genética , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Subunidade alfa 3 de Fator de Ligação ao Core/metabolismo , Células-Tronco Hematopoéticas/patologia , Síndromes Mielodisplásicas/patologia , Animais , Medula Óssea/patologia , Proteínas de Ligação a DNA/genética , Modelos Animais de Doenças , Humanos , Células Jurkat , Camundongos , Camundongos Knockout , Síndromes Mielodisplásicas/genética , Cultura Primária de Células , Proteínas Proto-Oncogênicas/genética , Transcrição Genética
20.
PLoS One ; 15(4): e0229593, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32324791

RESUMO

Acute myeloid leukaemia (AML) is characterised by phenotypic heterogeneity, which we hypothesise is a consequence of deregulated differentiation with transcriptional reminiscence of the normal compartment or cell-of-origin. Here, we propose a classification system based on normal myeloid progenitor cell subset-associated gene signatures (MAGS) for individual assignments of AML subtypes. We generated a MAGS classifier including the progenitor compartments CD34+/CD38- for haematopoietic stem cells (HSCs), CD34+/CD38+/CD45RA- for megakaryocyte-erythroid progenitors (MEPs), and CD34+/CD38+/CD45RA+ for granulocytic-monocytic progenitors (GMPs) using regularised multinomial regression with three discrete outcomes and an elastic net penalty. The regularisation parameters were chosen by cross-validation, and MAGS assignment accuracy was validated in an independent data set (N = 38; accuracy = 0.79) of sorted normal myeloid subpopulations. The prognostic value of MAGS assignment was studied in two clinical cohorts (TCGA: N = 171; GSE6891: N = 520) and had a significant prognostic impact. Furthermore, multivariate Cox regression analysis using the MAGS subtype, FAB subtype, cytogenetics, molecular genetics, and age as explanatory variables showed independent prognostic value. Molecular characterisation of subtypes by differential gene expression analysis, gene set enrichment analysis, and mutation patterns indicated reduced proliferation and overrepresentation of RUNX1 and IDH2 mutations in the HSC subtype; increased proliferation and overrepresentation of CEBPA mutations in the MEP subtype; and innate immune activation and overrepresentation of WT1 mutations in the GMP subtype. We present a differentiation-dependent classification system for AML subtypes with distinct pathogenetic and prognostic importance that can help identify candidates poorly responding to combination chemotherapy and potentially guide alternative treatments.


Assuntos
Células-Tronco Hematopoéticas/metabolismo , Leucemia Mieloide Aguda/genética , Células Mieloides/metabolismo , Células-Tronco/metabolismo , ADP-Ribosil Ciclase 1/genética , Antígenos CD34/genética , Diferenciação Celular/genética , Linhagem da Célula/genética , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Células-Tronco Hematopoéticas/patologia , Humanos , Isocitrato Desidrogenase/genética , Leucemia Mieloide Aguda/patologia , Antígenos Comuns de Leucócito/genética , Masculino , Pessoa de Meia-Idade , Mutação/genética , Células Mieloides/patologia , Análise de Componente Principal , Análise de Regressão , Células-Tronco/patologia , Proteínas WT1/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...