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1.
Nat Commun ; 12(1): 520, 2021 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-33483506

RESUMO

The fusion oncogene RUNX1/RUNX1T1 encodes an aberrant transcription factor, which plays a key role in the initiation and maintenance of acute myeloid leukemia. Here we show that the RUNX1/RUNX1T1 oncogene is a regulator of alternative RNA splicing in leukemic cells. The comprehensive analysis of RUNX1/RUNX1T1-associated splicing events identifies two principal mechanisms that underlie the differential production of RNA isoforms: (i) RUNX1/RUNX1T1-mediated regulation of alternative transcription start site selection, and (ii) direct or indirect control of the expression of genes encoding splicing factors. The first mechanism leads to the expression of RNA isoforms with alternative structure of the 5'-UTR regions. The second mechanism generates alternative transcripts with new junctions between internal cassettes and constitutive exons. We also show that RUNX1/RUNX1T1-mediated differential splicing affects several functional groups of genes and produces proteins with unique conserved domain structures. In summary, this study reveals alternative splicing as an important component of transcriptome re-organization in leukemia by an aberrant transcriptional regulator.


Assuntos
Processamento Alternativo , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Regulação Leucêmica da Expressão Gênica , Leucemia Mieloide/genética , Proteínas de Fusão Oncogênica/genética , Proteína 1 Parceira de Translocação de RUNX1/genética , Doença Aguda , Linhagem Celular Tumoral , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Perfilação da Expressão Gênica/métodos , Humanos , Leucemia Mieloide/patologia , Modelos Genéticos , Proteínas de Fusão Oncogênica/metabolismo , Interferência de RNA , Isoformas de RNA/genética , Isoformas de RNA/metabolismo , Proteína 1 Parceira de Translocação de RUNX1/metabolismo , Sítio de Iniciação de Transcrição
2.
Nat Commun ; 11(1): 3339, 2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32620764

RESUMO

Chromosomal NUP98-PHF23 translocation is associated with an aggressive form of acute myeloid leukemia (AML) and poor survival rate. Here, we report the molecular mechanisms by which NUP98-PHF23 recognizes the histone mark H3K4me3 and is inhibited by small molecule compounds, including disulfiram that directly targets the PHD finger of PHF23 (PHF23PHD). Our data support a critical role for the PHD fingers of NUP98-PHF23, and related NUP98-KDM5A and NUP98-BPTF fusions in driving leukemogenesis, and demonstrate that blocking this interaction in NUP98-PHF23 expressing AML cells leads to cell death through necrotic and late apoptosis pathways. An overlap of NUP98-KDM5A oncoprotein binding sites and H3K4me3-positive loci at the Hoxa/b gene clusters and Meis1 in ChIP-seq, together with NMR analysis of the H3K4me3-binding sites of the PHD fingers from PHF23, KDM5A and BPTF, suggests a common PHD finger-dependent mechanism that promotes leukemogenesis by this type of NUP98 fusions. Our findings highlight the direct correlation between the abilities of NUP98-PHD finger fusion chimeras to associate with H3K4me3-enriched chromatin and leukemic transformation.


Assuntos
Cromatina/metabolismo , Proteínas de Homeodomínio/metabolismo , Leucemia Mieloide/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Proteínas de Fusão Oncogênica/metabolismo , Doença Aguda , Antígenos Nucleares/genética , Antígenos Nucleares/metabolismo , Cromatina/genética , Dissulfiram/farmacologia , Histonas/metabolismo , Proteínas de Homeodomínio/genética , Humanos , Leucemia Mieloide/genética , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Proteínas de Fusão Oncogênica/genética , Dedos de Zinco PHD/genética , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteína 2 de Ligação ao Retinoblastoma/genética , Proteína 2 de Ligação ao Retinoblastoma/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Translocação Genética/efeitos dos fármacos , Translocação Genética/genética
3.
Nat Commun ; 11(1): 1659, 2020 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-32246016

RESUMO

Oncogenic Ras mutations occur in various leukemias. It was unclear if, besides the direct transforming effect via constant RAS/MEK/ERK signaling, an inflammation-related effect of KRAS contributes to the disease. Here, we identify a functional link between oncogenic KrasG12D and NLRP3 inflammasome activation in murine and human cells. Mice expressing active KrasG12D in the hematopoietic system developed myeloproliferation and cytopenia, which is reversed in KrasG12D mice lacking NLRP3 in the hematopoietic system. Therapeutic IL-1-receptor blockade or NLRP3-inhibition reduces myeloproliferation and improves hematopoiesis. Mechanistically, KrasG12D-RAC1 activation induces reactive oxygen species (ROS) production causing NLRP3 inflammasome-activation. In agreement with our observations in mice, patient-derived myeloid leukemia cells exhibit KRAS/RAC1/ROS/NLRP3/IL-1ß axis activity. Our findings indicate that oncogenic KRAS not only act via its canonical oncogenic driver function, but also enhances the activation of the pro-inflammatory RAC1/ROS/NLRP3/IL-1ß axis. This paves the way for a therapeutic approach based on immune modulation via NLRP3 blockade in KRAS-mutant myeloid malignancies.


Assuntos
Inflamassomos/imunologia , Transtornos Mieloproliferativos/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Animais , Proliferação de Células , Expressão Gênica , Hematopoese , Humanos , Inflamassomos/metabolismo , Interleucina-1beta/metabolismo , Leucemia Mieloide/etiologia , Leucemia Mieloide/genética , Camundongos , Camundongos Endogâmicos C57BL , Terapia de Alvo Molecular , Células Mieloides/metabolismo , Proteínas NLR/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
4.
Sci Rep ; 10(1): 4936, 2020 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-32188925

RESUMO

The toxicity of heavy metals present in binary semiconductor nanoparticles also known as quantum dots (QDs) has hindered their wide applications hence the advent of non-toxic ternary quantum dots. These new group of quantum dots have been shown to possess some therapeutic action against cancer cell lines but not significant enough to be referred to as an ideal therapeutic agent. In this report, we address this problem by conjugating red emitting CuInS/ZnS QDs to a 5,10,15,20-tetrakis(3-hydroxyphenyl)porphyrin -photosensitizer for improved bioactivities. The glutathione capped CuInS/ZnS QDs were synthesized in an aqueous medium using a kitchen pressure cooker at different Cu: In ratios (1:4 and 1:8) and at varied temperatures (95 °C, 190 °C and 235 °C). Optical properties show that the as-synthesized CuInS/ZnS QDs become red-shifted compared to the core (CuInS) after passivation with emission in the red region while the cytotoxicity study revealed excellent cell viability against normal kidney fibroblasts (BHK21). The highly fluorescent, water-soluble QDs were conjugated to 5,10,15,20-tetrakis(3-hydroxyphenyl)porphyrin (mTHPP) via esterification reactions at room temperature. The resultant water-soluble conjugate was then used for the cytotoxicity, fluorescent imaging and gene expression study against human monocytic leukemia cells (THP-1). Our result showed that the conjugate possessed high cytotoxicity against THP-1 cells with enhanced localized cell uptake compared to the bare QDs. In addition, the gene expression study revealed that the conjugate induced inflammation compared to the QDs as NFKB gene was over-expressed upon cell inflammation while the singlet oxygen (1O2) study showed the conjugate possessed large amount of 1O2, three times than the bare porphyrin. Thus, the as-synthesized conjugate looks promising as a therapeutic agent for cancer therapy.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Nanopartículas Metálicas , Porfirinas , Pontos Quânticos/efeitos adversos , Sulfetos , Compostos de Zinco , Linhagem Celular Tumoral , Humanos , Leucemia Mieloide/genética , Leucemia Mieloide/metabolismo , Nanopartículas Metálicas/química , Microscopia Confocal , Análise Espectral , Sulfetos/química , Nanomedicina Teranóstica , Compostos de Zinco/química
5.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(1): 40-50, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32027251

RESUMO

OBJECTIVE: To investigate the correlation of single nucleotide polymorphisms (SNP) in arachidonate 5-lipoxygenase gene (ALOX5) rs2029253, rs2228064 and rs2228065 sites, 5-lipoxygenase activating protein gene (ALOX5AP) rs10507391, rs4769874 sites with the risk for genesis of adult myeloid leukemia. METHODS: By the approval from the hospital ethics committee and the informed consent of participants. 150 patients with myeloid leukemia (ML) as ML group and 134 healthy people as the control group were selected. The genomic DNA was extracted from the samples. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) combined with directly sequencing, PCR-amplified products were applied to test the polymorphism of 5 sites in ALOX5 and ALOX5AP gene. RESULTS: A allele frequencies of ALOX5 gene rs2029253 site in the ML group and the control group were 43.0% and 34.3%, respectively. And the G allele frequencies in the ML group and the control group were 57.0% and 65.7%, respectively. The genotype distributions of AA, AG and GG in ALOX5 gene rs2029253 site in the ML group were 32.2%, 21.5% and 46.3% respectively. That in the control group were 15.7%, 37.3% and 47.0% respectively. The genotype AA and A allele frequency of ALOX5 gene rs2029253 site were linked with the increased risk of myeloid leukemia (OR=2.26, 95% CI: 1.43-4.56, P<0.05; OR=1.44, 95% CI: 1.02-2.03, P<0.05). And the genotype AG and allele G reduced the susceptibility to myeloid leukemia (OR=0.46, 95% CI: 0.27-0.78, P<0.01; OR=0.69, 95% CI: 0.50-0.98, P<0.05), however, the polymorphisms of ALOX5 gene rs2228064 and rs2228065 site not correlated with the risk of myeloid leukemia (P>0.05). The A allele frequency of ALOX5AP gene rs10507391 site in the ML group and the control group were 30.7% and 36.2% respectirely. The genotype distribution rates of AA, AT and TT in ALOX5AP gene rs10507391 site in the ML group was 1.3%, 58.7% and 40.0% respectively, that in the control group were 9.7%, 53.0% and 37.3% respectively. The genotype AA of ALOX5AP gene rs10507391 site correlated with the decreased risk of myeloid leukemia (OR=0.13, 95% CI: 0.03-0.57, P<0.05), but the polymorphism of ALOX5AP gene rs4769874 site not correlated with the risk of myeloid leukemia (P>0.05). CONCLUSION: The genotype AA, AG and allele A, G of ALOX5 rs2029253, as well as ALOX5AP rs10507391 may be correlate with the susceptibility to myeloid leukemia.


Assuntos
Proteínas Ativadoras de 5-Lipoxigenase/genética , Araquidonato 5-Lipoxigenase/genética , Leucemia Mieloide , Adulto , Estudos de Casos e Controles , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Leucemia Mieloide/genética , Polimorfismo de Nucleotídeo Único , Fatores de Risco
6.
Exp Mol Pathol ; 114: 104399, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32032633

RESUMO

Acute myeloid leukemia (AML) is a complex hematological neoplasm with poor prognosis. At present, overwhelming evidence indicates that different genetic abnormalities are relevant to the pathogenesis of AML. Nevertheless, its exact molecular mechanism is still unknown. Recently, it was reported that lncRNAs play crucial roles in tumorigenesis. But, their role in the molecular pathogenesis of AML has not been extensively explored. GAS5, one of the earliest known lncRNAs, has an essential role in the formation and progression of multiple human cancers. It was recently demonstrated that GAS5 acts as a riborepressor of the Glucocorticoid receptor) GR) and abnormal levels of GAS5 may alter response of hematopoietic cells to glucocorticoids. GAS5 can have interaction with the GR that encoded by NR3C1 gene and inhibit its transcriptional activity. To test whether the genetic variants can be associated with AML risk, we genotyped rs55829688 (T > C) polymorphism in GAS5 and three NR3C1 SNPs namely rs6195, rs41423247 and rs6189/rs6190 in a population of 100 Iranian AML patients and 100 healthy subjects. The analysis of the data showed the frequency of alleles and genotypes of rs55829688 and rs6189/rs6190 polymorphisms did not differ between patients and healthy subjects. But, rs41423247 and rs6195 demonstrated a significant correlation with AML risk. The rs6195 was associated with higher AML susceptibility in the co-dominant (OR = 4.58, 95% CI = 2.11-9.981, P < .0001), dominant (OR = 4.55, 95% CI = 2.155-9.613, P < .0001), and over-dominant (OR = 4.43, 95% CI = 2.042-9.621, P < .0001) models. Also, the rs41423247 polymorphism was associated with higher risk of AML in co-dominant (OR = 2.07, 95% CI = 1.171-4.242, P = .012) and dominant (OR = 2.47, 95% CI = 1.192-5.142, P = .010) models. Furthermore, haplotype analysis (rs41423247, rs6189.rs6190, rs6195, and rs55829688 respectively) demonstrated that GGAT, CGGT, and GGGT haplotypes were associated with higher risk of AML in the studied population (p-values = .007, 0.042 and 0.044, respectively). The present study reveals a possible role for NR3C1 in the pathogenesis of AML.


Assuntos
Predisposição Genética para Doença , Leucemia Mieloide/genética , RNA Longo não Codificante/genética , Receptores de Glucocorticoides/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Criança , Pré-Escolar , Feminino , Estudos de Associação Genética , Genótipo , Haplótipos/genética , Humanos , Irã (Geográfico)/epidemiologia , Leucemia Mieloide/patologia , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética
7.
Clin Sci (Lond) ; 134(2): 261-271, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-31922199

RESUMO

Acute myeloid leukemia (AML) is a malignant disorder of hemopoietic stem cells. AML can escape immunosurveillance of natural killer (NK) by gene mutation, fusions and epigenetic modification. The mechanism of AML immune evasion is not clearly understood. Here we show that CD48 high expression is a favorable prognosis factor that is down-regulated in AML patients, which can help AML evade from NK cell recognition and killing. Furthermore, we demonstrate that CD48 expression is regulated by methylation and that a hypomethylating agent can increase the CD48 expression, which increases the NK cells killing in vitro. Finally, we show that CD48 high expression can reverse the AML immune evasion and activate NK cells function in vivo. The present study suggests that a combination the hypomethylating agent and NK cell infusion could be a new strategy to cure AML.


Assuntos
Antígeno CD48/imunologia , Epigênese Genética/imunologia , Inativação Gênica/imunologia , Leucemia Mieloide/imunologia , Evasão Tumoral/imunologia , Doença Aguda , Animais , Antimetabólitos Antineoplásicos/farmacologia , Antígeno CD48/genética , Linhagem Celular Tumoral , Células Cultivadas , Metilação de DNA/efeitos dos fármacos , Metilação de DNA/genética , Metilação de DNA/imunologia , Decitabina/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/imunologia , Humanos , Estimativa de Kaplan-Meier , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Leucemia Mieloide/tratamento farmacológico , Leucemia Mieloide/genética , Masculino , Camundongos Endogâmicos BALB C , Evasão Tumoral/genética , Ensaios Antitumorais Modelo de Xenoenxerto
8.
PLoS One ; 15(1): e0227986, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31978184

RESUMO

The diagnosis of myeloid neoplasms (MN) has significantly evolved through the last few decades. Next Generation Sequencing (NGS) is gradually becoming an essential tool to help clinicians with disease management. To this end, most specialized genetic laboratories have implemented NGS panels targeting a number of different genes relevant to MN. The aim of the present study is to evaluate the performance of four different targeted NGS gene panels based on their technical features and clinical utility. A total of 32 patient bone marrow samples were accrued and sequenced with 3 commercially available panels and 1 custom panel. Variants were classified by two geneticists based on their clinical relevance in MN. There was a difference in panel's depth of coverage. We found 11 discordant clinically relevant variants between panels, with a trend to miss long insertions. Our data show that there is a high risk of finding different mutations depending on the panel of choice, due both to the panel design and the data analysis method. Of note, CEBPA, CALR and FLT3 genes, remains challenging the use of NGS for diagnosis of MN in compliance with current guidelines. Therefore, conventional molecular testing might need to be kept in place for the correct diagnosis of MN for now.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , Leucemia Mieloide/genética , Genes Neoplásicos , Humanos , Mutação/genética
9.
Cancer ; 126(4): 765-774, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31742675

RESUMO

BACKGROUND: The impact of the allelic burden of ASXL1, DNMT3A, JAK2, TET2, and TP53 mutations on survival remains unclear in patients with newly diagnosed acute myeloid leukemia (AML). METHODS: The authors assessed bone marrow aspirates from 421 patients with newly diagnosed AML using next-generation sequencing for ASXL1, DNMT3A, JAK2, TET2, and TP53 mutations, defined as the presence of mutations in ASXL1, DNMT3A, JAK2, TET2, or TP53 with a minimum variant allele frequency (VAF) of 5%. RESULTS: A total of 71 patients (17%) had ASXL1 mutations, 104 patients (25%) had DNMT3A mutations, 16 patients (4%) had JAK2 mutations, 82 patients (20%) had TET2 mutations, and 86 patients (20%) had TP53 mutations. Among patients with each mutation, the median VAF of ASXL1 was 34.31% (range, 1.17%-58.62%), the median VAF of DNMT3A was 41.76% (range, 1.02%-91.66%), the median VAF of JAK2 was 46.70% (range, 10.4%-71.7%), the median VAF of TET2 was 42.78% (range, 2.26%-95.32%), and the median VAF of TP53 was 45.47% (range, 1.15%-93.74%). The composite complete response rate was 60%, and was 77% in patients with AML with and without ASXL1, DNMT3A, JAK2, TET2, or TP53 mutations, respectively (P = .006); the median overall survival was 11 months and 27 months, respectively (P < .001). Multivariate analysis identified age; an antecedent history of dysplasia; white blood cell count; adverse cytogenetic risk; previous treatment with an FLT3 inhibitor; and the VAF of ASXL1, DNMT3A, JAK2, TET2, TP53, and NPM1 mutations by next-generation sequencing as prognostic factors for overall survival. CONCLUSIONS: The VAF of ASXL1, DNMT3A, JAK2, TET2, TP53, and NPM1 mutations is associated with worse prognosis in patients with newly diagnosed AML.


Assuntos
Biomarcadores Tumorais/genética , Predisposição Genética para Doença/genética , Leucemia Mieloide/genética , Mutação , Doença Aguda , DNA (Citosina-5-)-Metiltransferases/genética , Proteínas de Ligação a DNA/genética , Feminino , Frequência do Gene , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Janus Quinase 2/genética , Estimativa de Kaplan-Meier , Leucemia Mieloide/diagnóstico , Masculino , Pessoa de Meia-Idade , Proteínas Nucleares/genética , Prognóstico , Proteínas Proto-Oncogênicas/genética , Proteínas Repressoras/genética , Estudos Retrospectivos , Proteína Supressora de Tumor p53/genética
10.
Int J Hematol ; 111(2): 241-246, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31713024

RESUMO

Germline DDX41 mutations were recently reported to cause MDS/AML and donor-derived leukemia after transplantation. While previously described in Western countries, DDX41 variants have not been reported in a Southeast Asian population. We performed targeted sequencing of blood or bone marrow samples from 109 Thai patients with myeloid malignancies. Among the 109 patients (75 MDS, 8 MPN, 11 MDS/MPN and 15 AML), the most frequent mutations were in ASXL1 (17.4%), TET2 (16.5%) and SRSF2 (12.8%), respectively. DDX41 variants were detectable in six (5.5%) cases. Four patients exhibited three presumable germline DDX41 mutations: p.S21fs (n = 2), p.F235fs (n = 1), and p.R339H (n = 1). While p.S21fs was previously reported in myeloid neoplasm, the latter two variants have not been described. Two of these cases harbored concomitant probable germline/somatic DDX41 mutations (p.S21fs/p.R525H and p.R339H/p.K494T), while the other two patients carried only somatic mutations (p.R525H and p.F438L). The p.K494T and p.F438L variants have not been previously reported. In patients with DDX41 alterations, the diagnoses were MDS with excess blasts (4), secondary AML (1) and low-risk MDS (1). In conclusion, we identified DDX41 variants in Thai patients with myeloid malignancies in which these variants could be used to assess predisposition to MDS in Southeast Asia.


Assuntos
RNA Helicases DEAD-box/genética , Leucemia Mieloide/genética , Mutação , Síndromes Mielodisplásicas/genética , Transtornos Mieloproliferativos/genética , Humanos , Tailândia
11.
Blood ; 135(4): 261-268, 2020 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-31697811

RESUMO

Clonal hematopoiesis (CH) of indeterminate potential (CHIP) is defined by mutations in myeloid cancer-associated genes with a variant allele frequency of at least 2%. Recent studies have suggested a possible genetic predisposition to CH. To further explore this phenomenon, we conducted a population-based study of 594 twins from 299 pairs aged 73 to 94 years, all with >20 years' follow-up. We sequenced DNA from peripheral blood with a customized 21-gene panel at a median coverage of 6179X. The casewise concordance rates for mutations were calculated to assess genetic predisposition. Mutations were identified in 214 (36%) of the twins. Whereas 20 twin pairs had mutations within the same genes, the exact same mutation was only observed in 2 twin pairs. No significant difference in casewise concordance between monozygotic and dizygotic twins was found for any specific gene, subgroup, or CHIP mutations overall, and no significant heritability could be detected. In pairs discordant for CHIP mutations, we tested if the affected twin died before the unaffected twin, as a direct measurement of the association of having CH when controlling for familial factors. A total of 127 twin pairs were discordant for carrying a mutation, and in 61 (48%) cases, the affected twin died first (P = .72). Overall, we did not find a genetic predisposition to CHIP mutations in this twin study. The previously described negative association of CHIP mutations on survival could not be confirmed in a direct comparison among twin pairs that were discordant for CHIP mutations.


Assuntos
Hematopoese , Leucemia Mieloide/genética , Gêmeos/genética , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Doenças em Gêmeos/genética , Feminino , Frequência do Gene , Predisposição Genética para Doença , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/mortalidade , Humanos , Leucemia Mieloide/mortalidade , Masculino , Mutação , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética
12.
IUBMB Life ; 72(1): 119-130, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31769932

RESUMO

Myeloid leukaemia of Down syndrome (ML-DS) is an acute megakaryoblastic/erythroid leukaemia uniquely found in children with Down syndrome (constitutive trisomy 21). It has a unique clinical course, being preceded by a pre-leukaemic condition known as transient abnormal myelopoiesis (TAM), and provides an excellent model to study multistep leukaemogenesis. Both TAM and ML-DS blasts carry acquired N-terminal truncating mutations in the erythro-megakaryocytic transcription factor GATA1. These result in exclusive production of a shorter isoform (GATA1s). The majority of TAM cases resolve spontaneously without the need for treatment; however, around 10% acquire additional cooperating mutations and transform to leukaemia, with differentiation block and clinically significant cytopenias. Transformation is driven by the acquisition of additional mutation(s), which cooperate with GATA1s to perturb normal haematopoiesis.


Assuntos
Síndrome de Down/patologia , Fator de Transcrição GATA1/genética , Leucemia Mieloide/patologia , Mutação , Síndrome de Down/genética , Humanos , Leucemia Mieloide/genética
13.
PLoS One ; 14(12): e0226212, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31825998

RESUMO

Recently, we have documented a hematopoietic NKL-code mapping physiological expression patterns of NKL homeobox genes in early hematopoiesis and in lymphopoiesis, which spotlights genes deregulated in lymphoid malignancies. Here, we enlarge this map to include normal NKL homeobox gene expressions in myelopoiesis by analyzing public expression profiling data and primary samples from developing and mature myeloid cells. We thus uncovered differential activities of six NKL homeobox genes, namely DLX2, HHEX, HLX, HMX1, NKX3-1 and VENTX. We further examined public expression profiling data of 251 acute myeloid leukemia (AML) and 183 myelodysplastic syndrome (MDS) patients, thereby identifying 24 deregulated genes. These results revealed frequent deregulation of NKL homeobox genes in myeloid malignancies. For detailed analysis we focused on NKL homeobox gene NANOG, which acts as a stem cell factor and is correspondingly expressed alone in hematopoietic progenitor cells. We detected aberrant expression of NANOG in a small subset of AML patients and in AML cell line NOMO-1, which served as a model. Karyotyping and genomic profiling discounted rearrangements of the NANOG locus at 12p13. But gene expression analyses of AML patients and AML cell lines after knockdown and overexpression of NANOG revealed regulators and target genes. Accordingly, NKL homeobox genes HHEX, DLX5 and DLX6, stem cell factors STAT3 and TET2, and the NOTCH-pathway were located upstream of NANOG while NKL homeobox genes HLX and VENTX, transcription factors KLF4 and MYB, and anti-apoptosis-factor MIR17HG represented target genes. In conclusion, we have extended the NKL-code to the myeloid lineage and thus identified several NKL homeobox genes deregulated in AML and MDS. These data indicate a common oncogenic role of NKL homeobox genes in both lymphoid and myeloid malignancies. For misexpressed NANOG we identified an aberrant regulatory network, which contributes to the understanding of the oncogenic activity of NKL homeobox genes.


Assuntos
Proteínas de Homeodomínio/metabolismo , Leucemia Mieloide/genética , Síndromes Mielodisplásicas/genética , Células Mieloides/metabolismo , Linhagem Celular Tumoral , Linhagem da Célula , Regulação da Expressão Gênica , Proteínas de Homeodomínio/antagonistas & inibidores , Proteínas de Homeodomínio/genética , Humanos , Cariótipo , Leucemia Mieloide/metabolismo , Leucemia Mieloide/patologia , Síndromes Mielodisplásicas/metabolismo , Síndromes Mielodisplásicas/patologia , Células Mieloides/citologia , Proteína Homeobox Nanog/antagonistas & inibidores , Proteína Homeobox Nanog/genética , Proteína Homeobox Nanog/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Fator de Transcrição STAT3/metabolismo , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
14.
Nat Commun ; 10(1): 5351, 2019 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-31767858

RESUMO

Long non-coding RNAs (lncRNAs) are important regulatory molecules that are implicated in cellular physiology and pathology. In this work, we dissect the functional role of the HOXB-AS3 lncRNA in patients with NPM1-mutated (NPM1mut) acute myeloid leukemia (AML). We show that HOXB-AS3 regulates the proliferative capacity of NPM1mut AML blasts in vitro and in vivo. HOXB-AS3 is shown to interact with the ErbB3-binding protein 1 (EBP1) and guide EBP1 to the ribosomal DNA locus. Via this mechanism, HOXB-AS3 regulates ribosomal RNA transcription and de novo protein synthesis. We propose that in the context of NPM1 mutations, HOXB-AS3 overexpression acts as a compensatory mechanism, which allows adequate protein production in leukemic blasts.


Assuntos
Leucemia Mieloide/genética , Mutação , Proteínas Nucleares/genética , RNA Longo não Codificante/genética , RNA Ribossômico/genética , Transcrição Genética , Doença Aguda , Animais , Linhagem Celular Tumoral , Proliferação de Células , Células HEK293 , Humanos , Células K562 , Leucemia Mieloide/patologia , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Biossíntese de Proteínas/genética , Células THP-1 , Transplante Heterólogo
15.
Sci Rep ; 9(1): 16991, 2019 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-31740742

RESUMO

Acute myeloid leukemia (AML) is a malignant hematological disease in which nearly half have normal cytogenetics. We have tried to find some significant molecular markers for this part of the cytogenetic normal AML, which hopes to provide a benefit for the diagnosis, molecular typing and prognosis prediction of AML patients. In the present study, we calculated and compared the gene expression profiles of cytogenetically normal acute myeloid leukemia (CN-AML) patients in database of The Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO) and dataset Vizome (a total of 632 CN-AML samples), and we have demonstrated a correlation between PDE7B gene and CN-AML. Then we proceeded to a survival analysis and prognostic risk analysis between the expression levels of PDE7B gene and CN-AML patients. The result showed that the event-free survival (EFS) and overall survival (OS) were significantly shorter in CN-AML patients with high PDE7B levels in each dataset. And we detected a significantly higher expression level of PDE7B in the leukemia stem cell (LSC) positive group. The Cox proportional hazards regression model showed that PDE7B is an independent risk predictor for CN-AML. All results indicate that PDE7B is an unfavorable prognostic factor for CN-AML.


Assuntos
Biomarcadores Tumorais/genética , Nucleotídeo Cíclico Fosfodiesterase do Tipo 7/genética , Análise Citogenética/métodos , Perfilação da Expressão Gênica/métodos , Regulação Leucêmica da Expressão Gênica , Leucemia Mieloide/genética , Doença Aguda , Intervalo Livre de Doença , Feminino , Humanos , Leucemia Mieloide/diagnóstico , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico
16.
Nat Commun ; 10(1): 4986, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31676777

RESUMO

Chemotherapy-resistant cancer recurrence is a major cause of mortality. In acute myeloid leukemia (AML), chemorefractory relapses result from the complex interplay between altered genetic, epigenetic and transcriptional states in leukemic cells. Here, we develop an experimental model system using in vitro lineage tracing coupled with exome, transcriptome and in vivo functional readouts to assess the AML population dynamics and associated molecular determinants underpinning chemoresistance development. We find that combining standard chemotherapeutic regimens with low doses of DNA methyltransferase inhibitors (DNMTi, hypomethylating drugs) prevents chemoresistant relapses. Mechanistically, DNMTi suppresses the outgrowth of a pre-determined set of chemoresistant AML clones with stemness properties, instead favoring the expansion of rarer and unfit chemosensitive clones. Importantly, we confirm the capacity of DNMTi combination to suppress stemness-dependent chemoresistance development in xenotransplantation models and primary AML patient samples. Together, these results support the potential of DNMTi combination treatment to circumvent the development of chemorefractory AML relapses.


Assuntos
Metilação de DNA , Resistencia a Medicamentos Antineoplásicos/genética , Leucemia Mieloide/genética , Transcriptoma/genética , Doença Aguda , Antibióticos Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Linhagem da Célula/genética , DNA (Citosina-5-)-Metiltransferase 1/antagonistas & inibidores , DNA (Citosina-5-)-Metiltransferase 1/genética , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , Decitabina/uso terapêutico , Doxorrubicina/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Humanos , Leucemia Mieloide/tratamento farmacológico , Leucemia Mieloide/patologia
17.
Clin Epigenetics ; 11(1): 143, 2019 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-31623675

RESUMO

BACKGROUND: Patients with haematological malignancies are often vitamin C deficient, and vitamin C is essential for the TET-induced conversion of 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC), the first step in active DNA demethylation. Here, we investigate whether oral vitamin C supplementation can correct vitamin C deficiency and affect the 5hmC/5mC ratio in patients with myeloid cancers treated with DNA methyltransferase inhibitors (DNMTis). RESULTS: We conducted a randomized, double-blinded, placebo-controlled pilot trial (NCT02877277) in Danish patients with myeloid cancers performed during 3 cycles of DNMTi-treatment (5-azacytidine, 100 mg/m2/d for 5 days in 28-day cycles) supplemented by oral dose of 500 mg vitamin C (n = 10) or placebo (n = 10) daily during the last 2 cycles. Fourteen patients (70%) were deficient in plasma vitamin C (< 23 µM) and four of the remaining six patients were taking vitamin supplements at inclusion. Global DNA methylation was significantly higher in patients with severe vitamin C deficiency (< 11.4 µM; 4.997 vs 4.656% 5mC relative to deoxyguanosine, 95% CI [0.126, 0.556], P = 0.004). Oral supplementation restored plasma vitamin C levels to the normal range in all patients in the vitamin C arm (mean increase 34.85 ± 7.94 µM, P = 0.0004). We show for the first time that global 5hmC/5mC levels were significantly increased in mononuclear myeloid cells from patients receiving oral vitamin C compared to placebo (0.037% vs - 0.029%, 95% CI [- 0.129, - 0.003], P = 0.041). CONCLUSIONS: Normalization of plasma vitamin C by oral supplementation leads to an increase in the 5hmC/5mC ratio compared to placebo-treated patients and may enhance the biological effects of DNMTis. The clinical efficacy of oral vitamin C supplementation to DNMTis should be investigated in a large randomized, placebo-controlled clinical trial. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02877277 . Registered on 9 August 2016, retrospectively registered.


Assuntos
Ácido Ascórbico/administração & dosagem , Azacitidina/administração & dosagem , Metilação de DNA/efeitos dos fármacos , Leucemia Mieloide/terapia , Síndromes Mielodisplásicas/terapia , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Ácido Ascórbico/sangue , Ácido Ascórbico/farmacologia , Azacitidina/farmacologia , Ilhas de CpG/efeitos dos fármacos , Dinamarca , Método Duplo-Cego , Epigênese Genética/efeitos dos fármacos , Feminino , Humanos , Leucemia Mieloide/sangue , Leucemia Mieloide/genética , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/sangue , Síndromes Mielodisplásicas/genética , Projetos Piloto
18.
Clin Lab ; 65(10)2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31625367

RESUMO

BACKGROUND: To investigate the clinical features of and therapeutic options for a rare morphology resembling APL with t (11;12) (p15;q13) in acute myeloid leukemia. METHODS: One case of APL-like acute leukemia with a t (11;12) (p15;q13) translocation is reported and related literature is retrospectively reviewed. RESULTS: A rare acute myeloid leukemia with a t (11;12) (p15;q13) translocation was diagnosed by morphology, immunophenotyping, chromosome analysis, and fusion gene detection, without finding a classical t (15;17) (q24.1;q21.1) translocation and the PML-RARa fusion gene. The patient responded poorly to differentiation induction therapy with all-trans retinoic acid (ATRA) and arsenic trioxide (ATO). In the three previous cases re-ported, poor results were obtained with ATRA and/or ATO therapy. CONCLUSIONS: We reported a rare meaningful AML patient with t (11;12) (p15;q13). Standard AML regimens may be preferred. These APL-like leukemias may benefit from hematopoietic stem cell transplantation treatment. Further investigation involving more cases is needed to determine the role of t (11;12) (p15;q13) in AML and to find better therapy choices.


Assuntos
Leucemia Mieloide/genética , Proteínas de Fusão Oncogênica/genética , Translocação Genética , Doença Aguda , Antineoplásicos/uso terapêutico , Trióxido de Arsênio/uso terapêutico , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 12/genética , Humanos , Leucemia Mieloide/tratamento farmacológico , Leucemia Mieloide/patologia , Masculino , Literatura de Revisão como Assunto , Resultado do Tratamento , Tretinoína/uso terapêutico , Adulto Jovem
19.
Blood Adv ; 3(20): 2962-2979, 2019 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-31648317

RESUMO

Standardized variant curation is essential for clinical care recommendations for patients with inherited disorders. Clinical Genome Resource (ClinGen) variant curation expert panels are developing disease-associated gene specifications using the 2015 American College of Medical Genetics and Genomics (ACMG) and Association for Molecular Pathology (AMP) guidelines to reduce curation discrepancies. The ClinGen Myeloid Malignancy Variant Curation Expert Panel (MM-VCEP) was created collaboratively between the American Society of Hematology and ClinGen to perform gene- and disease-specific modifications for inherited myeloid malignancies. The MM-VCEP began optimizing ACMG/AMP rules for RUNX1 because many germline variants have been described in patients with familial platelet disorder with a predisposition to acute myeloid leukemia, characterized by thrombocytopenia, platelet functional/ultrastructural defects, and a predisposition to hematologic malignancies. The 28 ACMG/AMP codes were tailored for RUNX1 variants by modifying gene/disease specifications, incorporating strength adjustments of existing rules, or both. Key specifications included calculation of minor allele frequency thresholds, formulating a semi-quantitative approach to counting multiple independent variant occurrences, identifying functional domains and mutational hotspots, establishing functional assay thresholds, and characterizing phenotype-specific guidelines. Preliminary rules were tested by using a pilot set of 52 variants; among these, 50 were previously classified as benign/likely benign, pathogenic/likely pathogenic, variant of unknown significance (VUS), or conflicting interpretations (CONF) in ClinVar. The application of RUNX1-specific criteria resulted in a reduction in CONF and VUS variants by 33%, emphasizing the benefit of gene-specific criteria and sharing internal laboratory data.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/genética , Variação Genética , Mutação em Linhagem Germinativa , Leucemia Mieloide/diagnóstico , Leucemia Mieloide/genética , Tomada de Decisão Clínica , Gerenciamento Clínico , Estudos de Associação Genética , Predisposição Genética para Doença , Testes Genéticos , Genômica/métodos , Humanos , Fenótipo , Reprodutibilidade dos Testes
20.
Biochem Biophys Res Commun ; 519(4): 887-893, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31561854

RESUMO

We investigated the effect of the modulation of Na/H exchanger 1 (NHE1) on apoptosis, differentiation, and chemoresistance in acute myeloid leukemia (AML) cells to evaluate the possibility of NHE1 modulation as a novel therapeutic strategy for AML. The pHi of leukemia cell lines except KG1a was higher than that of normal bone marrow mononuclear cells (BM MNCs). Notably, in K562, cytarabine (AraC)-resistant OCI-AML2, and primary leukemia cells, pHi was significantly higher than that of normal BM MNCs. Western blotting and real-time quantitative PCR confirmed that the increased NHE1 expression was responsible for the higher pHi. Specifically, compared to CD34+CD38+ leukemia cells, the mean fluorescence intensity of NHE1 was significantly higher in CD34+CD38- leukemic stem cells. The out of range in pHi by treatment with an NHE inhibitor, the amiloride analogue 5-(N,N-hexamethylene) amiloride (HMA), or an NHE activator, phorbol 12-myristate 13-acetate (PMA), resulted in dose- and time-dependent inhibition of leukemia cell proliferation. PMA induced CD14+ differentiation of leukemia cells, whereas HMA induced cell cycle arrest at the G1 phase. HMA could induce apoptosis of leukemia cells even in AraC-resistant cells and showed an additive effect on apoptosis in AraC-sensitive cells. Our result revealed that AML cells prefer more alkalic intracellular moiety than normal BM MNCs following increased NHE1 expression and that NHE1 modulation can induce apoptosis and differentiation of AML cells. These findings imply that NHE1 is a potential target in cytotoxic or differentiation-induction treatment for AML.


Assuntos
Amilorida/farmacologia , Apoptose/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Trocador 1 de Sódio-Hidrogênio/antagonistas & inibidores , Acetato de Tetradecanoilforbol/farmacologia , Doença Aguda , Amilorida/química , Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Humanos , Células K562 , Leucemia Mieloide/genética , Leucemia Mieloide/metabolismo , Leucemia Mieloide/patologia , Trocador 1 de Sódio-Hidrogênio/genética , Trocador 1 de Sódio-Hidrogênio/metabolismo
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