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1.
Anticancer Res ; 39(8): 4165-4170, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31366501

RESUMO

AIM: To examine the influence of hypoxia on the in vitro growth of leukaemia cells and the activity of signalling proteins to better understand the pathophysiology of leukaemia cells in human bone marrow. MATERIALS AND METHODS: Six human leukaemia cell lines were cultured under normoxic or hypoxic conditions. Cell growth, recovery of clonogenic cells, and the expression and activation of various signalling proteins were examined. RESULTS: Hypoxia suppressed cell growth and the recovery of clonogenic cells. Moreover, hypoxia up-regulated hypoxia-inducible factor (HIF) 1α and HIF2α expression while suppressing the expression and activation of NOTCH1, mechanistic target of rapamycin kinase (mTOR) activation, and nuclear factor-kappa B (NF-κB) phosphorylation. CONCLUSION: We found that hypoxia up-regulated HIF expression while it suppressed the self-renewal capacity of leukaemia cells, NOTCH activity, and expression of its down-stream signalling molecules, which differs from previous reports mentioning that HIF activates NOTCH signalling. Our findings serve to further elucidate the in vivo pathophysiology of leukaemia cells.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Leucemia/genética , Receptor Notch1/genética , Ciclo Celular/genética , Hipóxia Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Leucêmica da Expressão Gênica/genética , Humanos , Leucemia/patologia , NF-kappa B/genética , Fosforilação , Proteínas Proto-Oncogênicas c-akt/genética , Transdução de Sinais/genética , Serina-Treonina Quinases TOR/genética
2.
Asia Pac J Clin Oncol ; 15(6): 364-370, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31264378

RESUMO

BACKGROUND: Despite advances in the treatment of acute promyelocytic leukemia (APL) with all-trans-retinoic acid (ATRA), its underlying mechanism has not been fully elucidated. The oncogenic microRNA cluster miR-17-92 modulates multiple cellular processes, including survival, proliferation, and apoptosis. However, the role of miR-17-92 and its regulation has not yet been documented for APL. METHODS: We analyzed miR-17-92 expression in APL samples and cell lines by qRT-PCR. The expression of c-Myc was measured by western blot. Cell differentiation was assessed by measuring the surface CD11b antigen expression by flow cytometry analysis. RESULTS: We observed that miR-17-92 was upregulated in APL compared with healthy donors. Furthermore, we demonstrated that expressions of c-Myc and miR-17-92 are markedly suppressed during ATRA-induced NB4 cell differentiation. Importantly, we also demonstrated that miR-17-92 is directly regulated by c-Myc during the granulocytic differentiation of APL cells. Finally, the overexpression of miR-17-5p blocks ATRA-induced differentiation. CONCLUSIONS: We report abnormal expression of the miR-17-92 cluster in APL cells, which is responsible for the differentiation block in blast cells in APL. In addition, we identified miR-17-92 as a target gene of c-Myc during ATRA-induced granulocytic differentiation.


Assuntos
Diferenciação Celular/genética , Leucemia Promielocítica Aguda/genética , MicroRNAs/genética , Proteínas Proto-Oncogênicas c-myc/genética , Antineoplásicos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Regulação Leucêmica da Expressão Gênica/genética , Humanos , Leucemia Promielocítica Aguda/tratamento farmacológico , Tretinoína/farmacologia
3.
Mol Biol Rep ; 46(3): 2679-2684, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31037549

RESUMO

Survivin is one of the major members of Inhibitory Apoptotic Proteins (IAP) family. The functional anti-apoptotic and regulatory role of Survivin in the cell cycle had made it as an interesting candidate for tumor studies. Acute lymphoblastic leukemia is one of the most common malignancies of children that accounts for 30% of all the childhood malignancies. The purpose of this study was to investigate the prognostic importance of Survivin level in B-cell acute lymphoblastic leukemia patients of Iran in four different steps of disease in order to follow up its impact on various treatment ways, the development of the disease, and the response to treatment in the patients. The expression level of Survivin was evaluated in 85 patients with B-cell acute lymphoblastic leukemia and 85 healthy controls using Quantitative Real-Time Polymerase Chain Reaction. Also, western blot analysis was done to confirm the results. Based on our findings, the expression of Survivin showed a significant up-regulation in patients compared to controls. Therefore, a correlation between Survivin expression and the development pattern of B-cell acute lymphoblastic leukemia with a strong diagnostic efficiency (AUC-ROC, 0.8562) was observed. Therefore, it can be introduced as a potential marker for prognosis B-cell Acute Lymphoblastic Leukemia in the future.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Survivina/genética , Adolescente , Apoptose/genética , Linfócitos B/metabolismo , Criança , Pré-Escolar , Progressão da Doença , Feminino , Regulação Leucêmica da Expressão Gênica/genética , Humanos , Lactente , Proteínas Inibidoras de Apoptose/genética , Irã (Geográfico) , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Prognóstico , Reação em Cadeia da Polimerase em Tempo Real , Survivina/metabolismo , Transcriptoma/genética
4.
Blood ; 133(25): 2651-2663, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-30923040

RESUMO

Targeted sequencing of 103 leukemia-associated genes in leukemia cells from 841 treatment-naive patients with chronic lymphocytic leukemia (CLL) identified 89 (11%) patients as having CLL cells with mutations in genes encoding proteins that putatively are involved in hedgehog (Hh) signaling. Consistent with this finding, there was a significant association between the presence of these mutations and the expression of GLI1 (χ2 test, P < .0001), reflecting activation of the Hh pathway. However, we discovered that 38% of cases without identified mutations also were GLI1+ Patients with GLI1+ CLL cells had a shorter median treatment-free survival than patients with CLL cells lacking expression of GLI1 independent of IGHV mutation status. We found that GANT61, a small molecule that can inhibit GLI1, was highly cytotoxic for GLI1+ CLL cells relative to that of CLL cells without GLI1. Collectively, this study shows that a large proportion of patients have CLL cells with activated Hh signaling, which is associated with early disease progression and enhanced sensitivity to inhibition of GLI1.


Assuntos
Proteínas Hedgehog/metabolismo , Leucemia Linfocítica Crônica de Células B/patologia , Proteína GLI1 em Dedos de Zinco/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Feminino , Regulação Leucêmica da Expressão Gênica/genética , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/metabolismo , Masculino , Pessoa de Meia-Idade , Piridinas/farmacologia , Pirimidinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
5.
Oncol Rep ; 41(5): 2876-2888, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30896832

RESUMO

The aim of the present study was to identify potential molecular mechanisms and therapeutic targets in regards to isocitrate dehydrogenase 2 (IDH2) R140Q-mutated acute myeloid leukemia (AML). An RNA sequencing dataset of IDH2 wild-type and R140Q-mutated adult de novo AML bone marrow samples was obtained from The Cancer Genome Atlas (TCGA) database. The edgeR package was used to screen for the differentially expressed genes (DEGs), and the potential molecular mechanisms and therapeutic targets were identified using Database for Annotation, Visualization, and Integrated Discovery (DAVID) v6.8, Biological Networks Gene Ontology tool, Connectivity Map (CMap), Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) and GeneMANIA. A total of 230 DEGs were identified between the bone marrow tissues of IDH2 R140Q-mutated and wild-type AML patients, of which 31 were significantly associated with overall survival (OS). Functional assessment of DEGs showed significant enrichment in multiple biological processes, including angiogenesis and cell differentiation. STRING and GeneMANIA were used to identify the hub genes of these DEGs. CMap analysis identified 13 potential small-molecule drugs against IDH2 R140Q-mutated adult de novo AML. Genome-wide co-expression network analysis identified several IDH2 R140Q co-expressed genes, of which 56 were significantly associated with AML OS. The difference in IDH2 mRNA expression levels and OS between the IDH2 R140Q-mutated and wild-type AML were not statistically significant in our cohort. In conclusion, we identified several co-expressing genes and potential molecular mechanisms that are instrumental in IDH2 R140Q-mutated adult de novo AML, along with 13 candidate targeted therapeutic drugs.


Assuntos
Regulação Leucêmica da Expressão Gênica/genética , Redes Reguladoras de Genes/genética , Isocitrato Desidrogenase/genética , Leucemia Mieloide Aguda/genética , Adulto , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Conjuntos de Dados como Assunto , Perfilação da Expressão Gênica , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Redes Reguladoras de Genes/efeitos dos fármacos , Genótipo , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/patologia , Terapia de Alvo Molecular/métodos , Mutação , Polimorfismo de Nucleotídeo Único , Análise de Sequência de RNA
6.
Proc Natl Acad Sci U S A ; 116(8): 3052-3061, 2019 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-30733284

RESUMO

Glucocorticoids (GCs) are used in combination chemotherapies as front-line treatment for B cell acute lymphoblastic leukemia (B-ALL). Although effective, many patients relapse and become resistant to chemotherapy and GCs in particular. Why these patients relapse is not clear. We took a comprehensive, functional genomics approach to identify sources of GC resistance. A genome-wide shRNA screen identified the transcriptional coactivators EHMT2, EHMT1, and CBX3 as important contributors to GC-induced cell death. This complex selectively supports GC-induced expression of genes contributing to cell death. A metaanalysis of gene expression data from B-ALL patient specimens revealed that Aurora kinase B (AURKB), which restrains GC signaling by phosphorylating EHMT1-2, is overexpressed in relapsed B-ALL, suggesting it as a potential contributor to relapse. Inhibition of AURKB enhanced GC-induced expression of cell death genes, resulting in potentiation of GC cytotoxicity in cell lines and relapsed B-ALL patient samples. This function for AURKB is distinct from its canonical role in the cell cycle. These results show the utility of functional genomics in understanding mechanisms of resistance and rapidly identifying combination chemotherapeutics.


Assuntos
Aurora Quinase B/genética , Morte Celular/genética , Resistencia a Medicamentos Antineoplásicos/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamento farmacológico , Linhagem Celular Tumoral , Proteínas Cromossômicas não Histona/genética , Regulação Leucêmica da Expressão Gênica/genética , Glucocorticoides/genética , Glucocorticoides/farmacologia , Antígenos de Histocompatibilidade/genética , Histona-Lisina N-Metiltransferase/genética , Humanos , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patologia , RNA Interferente Pequeno/genética , Recidiva
7.
Mol Biol Rep ; 46(2): 2293-2298, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30747385

RESUMO

Acute myeloid leukaemia (AML) is a heterogeneous disorder of haematopoietic stem cells or progenitor cells. Metalloproteinases (MMPs) are proteolytic enzymes whose activity is increased in different types of solid tumours. These enzymes regulate many processes associated with tumour progression. In haematological malignancy, the role of MMPs seems to be underestimated, and only metalloproteinase 2 (MMP2) and metalloproteinase 9 (MMP9) have been widely examined so far. In this work, differences in metalloproteinase 1 (MMP1) gene expression between patients with AML and healthy individuals were assessed. The relative expression level of the MMP1 gene was obtained by a real time PCR method preceded by reverse transcription. The relative level of MMP1 gene expression in patients with AML was decreased when compared to that of the control group. The role of MMP1 in AML could be different from that in solid tumours. Decreased MMP1 gene expression in AML similar to that of MMP9, shows a greater role for MMP1 in normal haematopoiesis than in the development of leukaemic cells.


Assuntos
Leucemia Mieloide Aguda/genética , Metaloproteinase 1 da Matriz/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Expressão Gênica , Regulação Leucêmica da Expressão Gênica/genética , Humanos , Leucemia Mieloide Aguda/metabolismo , Masculino , Metaloproteinase 1 da Matriz/metabolismo , Metaloproteinases da Matriz/genética , Metaloproteinases da Matriz/metabolismo , Pessoa de Meia-Idade , Transcriptoma/genética
8.
Leukemia ; 33(3): 612-624, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30209403

RESUMO

Leukemic relapse is frequently accompanied by progressively aggressive clinical course. To understand the molecular mechanism of leukemic relapse, MLL/AF9-transformed mouse leukemia cells were serially transplanted in C57BL/6 mice (N = 96) by mimicking repeated recurrences, where mutations were monitored by exome sequencing (N = 42). The onset of leukemia was progressively promoted with advanced transplants, during which increasing numbers of somatic mutations were acquired (P < 0.005). Among these, mutations in Ptpn11 (p.G60R) and Braf (p.V637E) corresponded to those identified in human MLL-AML, while recurrent mutations affecting Msn (p.R295C) were observed only in mouse but not in human MLL-AML. Another mutated gene of interest was Gnb2 which was reported to be recurrently mutated in various hematological neoplasms. Gnb2 mutations (p.G77R) were significantly increased in clone size (P = 0.007) and associated with earlier leukemia onset (P = 0.011). GNB2 transcripts were significantly upregulated in human MLL-AML compared to MLL-negative AML (P < 0.05), which was supported by significantly increased Gnb2 transcript induced by MLL/AF9 overexpression (P < 0.001). In in vivo model, both mutation and overexpression of GNB2 caused leukemogenesis, and downregulation of GNB2 expression reduced proliferative potential and survival benefit, suggesting a driver role of GNB2. In conclusion, alterations of driver genes over time may play an important role in the progression of MLL-AML.


Assuntos
Histona-Lisina N-Metiltransferase/genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Proteína de Leucina Linfoide-Mieloide/genética , Animais , Proliferação de Células/genética , Progressão da Doença , Regulação para Baixo/genética , Proteínas de Ligação ao GTP/genética , Regulação Leucêmica da Expressão Gênica/genética , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Mutação/genética , Proteínas de Fusão Oncogênica/genética , Regulação para Cima/genética
9.
Nat Genet ; 51(1): 151-162, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30420649

RESUMO

Acute myeloid leukemia (AML) is a heterogeneous disease caused by a variety of alterations in transcription factors, epigenetic regulators and signaling molecules. To determine how different mutant regulators establish AML subtype-specific transcriptional networks, we performed a comprehensive global analysis of cis-regulatory element activity and interaction, transcription factor occupancy and gene expression patterns in purified leukemic blast cells. Here, we focused on specific subgroups of subjects carrying mutations in genes encoding transcription factors (RUNX1, CEBPα), signaling molecules (FTL3-ITD, RAS) and the nuclear protein NPM1). Integrated analysis of these data demonstrates that each mutant regulator establishes a specific transcriptional and signaling network unrelated to that seen in normal cells, sustaining the expression of unique sets of genes required for AML growth and maintenance.


Assuntos
Regulação Leucêmica da Expressão Gênica/genética , Redes Reguladoras de Genes/genética , Leucemia Mieloide Aguda/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transdução de Sinais/genética , Fatores de Transcrição/genética , Adulto Jovem
10.
Mol Med Rep ; 19(1): 508-514, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30483794

RESUMO

MicroRNAs (miRNAs) have been demonstrated to regulate the progression of numerous types of cancer, including acute myeloid leukemia (AML). Previous studies demonstrated that miR­1271­5p functions as a tumor suppressor; however, the roles of miR­1271­5p in AML remain unknown. In the present study, miR­1271­5p was significantly downregulated in AML tissues compared with normal tissues by reverse transcription­quantitative polymerase chain reaction analysis. Furthermore, the expression levels of miR­1271­5p in patients with AML may function as a prognostic marker. In addition, overexpression of miR­1271­5p significantly suppressed the proliferation and induced apoptosis of AML cells by Cell Counting kit­8 and fluorescence activated cell sorter assays; miR­1271­5p downregulation exhibited opposing effects. Additionally, transcription factor ZIC2 may be a direct target of miR­1271­5p in AML cells, which was demonstrated by a luciferase reporter assay and RNA pulldown assay. Overexpression of miR­1271­5p significantly reduced the mRNA and protein expression levels of ZIC2 in AML193 and OCI­AML2 cells by reverse transcription­quantitative polymerase chain reaction analysis and western blotting. Furthermore, an inverse correlation between miR­1271­5p and ZIC2 expression in AML samples was observed. In summary, ZIC2 was upregulated in AML tissues, and restoration of ZIC2 expression was able to promote the proliferation and reduce the apoptosis of AML cells transfected with miR­1271­5p mimics. The results of the present study demonstrated that miR­1271­5p inhibited the progression of AML by targeting ZIC2.


Assuntos
Apoptose/genética , Proliferação de Células/genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , MicroRNAs/genética , Proteínas Nucleares/genética , Fatores de Transcrição/genética , Adolescente , Adulto , Linhagem Celular , Linhagem Celular Tumoral , Criança , Pré-Escolar , Regulação para Baixo/genética , Feminino , Regulação Leucêmica da Expressão Gênica/genética , Células HL-60 , Humanos , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , Adulto Jovem
11.
Cancer Cell ; 34(6): 982-995.e7, 2018 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-30503705

RESUMO

Enhancer profiling is a powerful approach for discovering cis-regulatory elements that define the core transcriptional regulatory circuits of normal and malignant cells. Gene control through enhancer activity is often dominated by a subset of lineage-specific transcription factors. By integrating measures of chromatin accessibility and enrichment for H3K27 acetylation, we have generated regulatory landscapes of chronic lymphocytic leukemia (CLL) samples and representative cell lines. With super enhancer-based modeling of regulatory circuits and assessments of transcription factor dependencies, we discover that the essential super enhancer factor PAX5 dominates CLL regulatory nodes and is essential for CLL cell survival. Targeting enhancer signaling via BET bromodomain inhibition disrupts super enhancer-dependent gene expression with selective effects on CLL core regulatory circuitry, conferring potent anti-tumor activity.


Assuntos
Cromatina/genética , Elementos Facilitadores Genéticos/genética , Regulação Leucêmica da Expressão Gênica/genética , Leucemia Linfocítica Crônica de Células B/genética , Acetilação , Animais , Azepinas/farmacologia , Linhagem Celular Tumoral , Cromatina/efeitos dos fármacos , Cromatina/metabolismo , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Histonas/metabolismo , Humanos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/metabolismo , Camundongos Knockout , Fator de Transcrição PAX5/genética , Fator de Transcrição PAX5/metabolismo , Ligação Proteica , Proteínas/antagonistas & inibidores , Proteínas/genética , Proteínas/metabolismo , Triazóis/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
12.
Cell Death Dis ; 9(12): 1160, 2018 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-30478302

RESUMO

As previously reported, chronic lymphocytic leukemia (CLL) cells show constitutive Notch1/2 activation and express the Notchligand Jagged1. Despite increasing knowledge of the impact of Notch alterations on CLL biology and pathogenesis, the role of Jagged1 expressed in CLL cells remains undefined. In other cell types, it has been shown that after Notch engagement, Jagged1 not only activates Notch in signal-receiving cell, but also undergoes proteolytic activation in signal-sending cell, triggering a signaling with biological effects. We investigated whether Jagged1 expressed in CLL cells undergoes proteolytic processing and/or is able to induce Notch activation through autocrine/paracrine loops, focusing on the effect that CLL prosurvival factor IL-4 could exert on the Notch-Jagged1 system in these cells. We found that Jagged1 was constitutively processed in CLL cells and generated an intracellular fragment that translocated into the nucleus, and an extracellular fragment released into the culture supernatant. IL-4 enhanced expression of Jagged1 and its intracellular fragments, as well as Notch1/2 activation. The IL-4-induced increase in Notch1/2 activation was independent of the concomitant upregulated Jagged1 levels. Indeed, blocking Notch-Jagged1 interactions among CLL cells with Jagged1 neutralizing antibodies did not affect the expression of the Notch target Hes1. Notably, anti-Jagged1 antibodies partially prevented the IL-4-induced increase in Jagged1 processing and cell viability, suggesting that Jagged1 processing is one of the events contributing to IL-4-induced CLL cell survival. Consistent with this, Jagged1 silencing by small interfering RNA partially counteracted the capacity of IL-4 to promote CLL cell survival. Investigating the pathways whereby IL-4 promoted Notch1/2 activation in CLL cells independent of Jagged1, we found that PI3Kδ/AKT and PKCδ were involved in upregulating Notch1 and Notch2 proteins, respectively. Overall, this study provides new insights into the Notch-ligand system in CLL cells and suggests that targeting this system may be exploited as a novel/additional therapy approach for CLL.


Assuntos
Interleucina-4/genética , Proteína Jagged-1/genética , Leucemia Linfocítica Crônica de Células B/genética , Apoptose/genética , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Feminino , Regulação Leucêmica da Expressão Gênica/genética , Humanos , Leucemia Linfocítica Crônica de Células B/patologia , Masculino , Proteína Quinase C-delta/genética , RNA Interferente Pequeno/genética , Receptor Notch1/genética , Receptor Notch2/genética , Transdução de Sinais
13.
Cancer Cell ; 34(4): 626-642.e8, 2018 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-30300583

RESUMO

Oncogenic transcription factors such as the leukemic fusion protein RUNX1/ETO, which drives t(8;21) acute myeloid leukemia (AML), constitute cancer-specific but highly challenging therapeutic targets. We used epigenomic profiling data for an RNAi screen to interrogate the transcriptional network maintaining t(8;21) AML. This strategy identified Cyclin D2 (CCND2) as a crucial transmitter of RUNX1/ETO-driven leukemic propagation. RUNX1/ETO cooperates with AP-1 to drive CCND2 expression. Knockdown or pharmacological inhibition of CCND2 by an approved drug significantly impairs leukemic expansion of patient-derived AML cells and engraftment in immunodeficient murine hosts. Our data demonstrate that RUNX1/ETO maintains leukemia by promoting cell cycle progression and identifies G1 CCND-CDK complexes as promising therapeutic targets for treatment of RUNX1/ETO-driven AML.


Assuntos
Pontos de Checagem do Ciclo Celular/genética , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Ciclina D2/genética , Animais , Linhagem Celular Tumoral , Cromossomos Humanos Par 21/genética , Regulação Leucêmica da Expressão Gênica/genética , Humanos , Leucemia Mieloide Aguda/genética , Masculino , Camundongos , Proteínas de Fusão Oncogênica/genética , Oncogenes/genética , Translocação Genética/genética
14.
Mol Biol Rep ; 45(6): 2491-2499, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30350234

RESUMO

Acute myeloid leukemia (AML) has the highest rate of mortality among the leukemias. Disruption in miRNAs level is involved in the pathogenesis of the disease. The miR-155 has a role in primary differentiation of myeloid progenitor. Meanwhile, there is little knowledge about the effects of sulforaphane against leukemia. The present study tried to evaluate pathologic effect of miR-155 in patients in various subgroups of AML, and then pioneered in assessing miR-155 levels by the effect of sulforaphane in different AML cell lines. The miR-155 level was significantly higher in patients with AML compared to the controls. Interestingly, the increase in miR-155 was converged with raising the subtype of AML (from M1 to M5). The miR-155 levels increased by 1.2 times in patients with M1, but this increase reached 2.5 times in the patients in the M5 subgroup. Sulforaphane reduced the number of live cells and increased the mortality rate of AML cells particularly by induction of apoptosis. However, the anti-proliferative effect of this agent was more dominant and could dose-dependently lessen miR-155 levels in myeloid leukemia cells. More or less, about 80% reduction in miR-155 expression was almost observed after 48 h treatment with 60 µM sulforaphane in all four studied cell lines. The obtained results indicated that miR-155 might function as an oncomir in AML and can potentially be considered as a prognosis biomarker for AML. The anti-cancer effects of sulforaphane can be correlated with reduction of miR-155 levels. These findings suggested that sulforaphane could induce more differentiation in myeloid progenitor cells through controlling the miR-155, thereby mitigating the progress of AML.


Assuntos
Isotiocianatos/farmacologia , Leucemia Mieloide Aguda/genética , MicroRNAs/efeitos dos fármacos , Adolescente , Adulto , Idoso , Apoptose/efeitos dos fármacos , Biomarcadores Tumorais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Criança , Pré-Escolar , Progressão da Doença , Feminino , Regulação Leucêmica da Expressão Gênica/genética , Humanos , Leucemia Mieloide Aguda/metabolismo , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Transdução de Sinais
15.
J Clin Invest ; 128(12): 5465-5478, 2018 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-30277471

RESUMO

Chronic lymphocytic leukemia (CLL) is characterized by clonal proliferation and progressive accumulation of mature B lymphocytes in the peripheral blood, lymphoid tissues, and bone marrow. CLL is characterized by profound immune defects leading to severe infectious complications. T cells are numerically, phenotypically, and functionally highly abnormal in CLL, with only limited ability to exert antitumor immune responses. Exhaustion of T cells has also been suggested to play an important role in antitumor responses. CLL-mediated T cell exhaustion is achieved by the aberrant expression of several inhibitory molecules on CLL cells and their microenvironment, prominently the programmed cell death ligand 1/programmed cell death 1 (PD-L1/PD-1) receptors. Previously, we showed that CD84, a member of the SLAM family of receptors, bridges between CLL cells and their microenvironment. In the current study, we followed CD84 regulation of T cell function. We showed that cell-cell interaction mediated through human and mouse CD84 upregulates PD-L1 expression on CLL cells and in their microenvironment and PD-1 expression on T cells. This resulted in suppression of T cell responses and activity in vitro and in vivo. Thus, our results demonstrate a role for CD84 in the regulation of immune checkpoints by leukemia cells and identify CD84 blockade as a therapeutic strategy to reverse tumor-induced immune suppression.


Assuntos
Antígeno B7-H1/imunologia , Regulação Leucêmica da Expressão Gênica/imunologia , Leucemia Linfocítica Crônica de Células B/imunologia , Proteínas de Neoplasias/imunologia , Receptor de Morte Celular Programada 1/imunologia , Família de Moléculas de Sinalização da Ativação Linfocitária/imunologia , Animais , Antígeno B7-H1/genética , Regulação Leucêmica da Expressão Gênica/genética , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/patologia , Camundongos , Camundongos Knockout , Proteínas de Neoplasias/genética , Receptor de Morte Celular Programada 1/genética , Família de Moléculas de Sinalização da Ativação Linfocitária/genética
16.
Exp Hematol ; 68: 80-88.e2, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30195077

RESUMO

BCR-ABL1-independent mechanisms had been thought to mediate drug resistance to tyrosine kinase inhibitors (TKIs) in patients with chronic myelogenous leukemia (CML). The pro-oncogenic anterior gradient 2 (AGR2) mediates drug resistance of cancer cells. In this study, we observed an increased level of AGR2 in TKI-resistant CML cells. Silence of AGR2 in dasatinib-resistant K562 (K562DR) cells led to restored sensitivity to dasatinib both in vitro and in vivo. Exposure to dasatinib induced upregulation of AGR2 in K562 cells, which indicated a probable treatment-related drug resistance. We further investigated the potential interaction between microRNA (miRNA) and AGR2 in K562DR cells and found that downregulation of miR-217 was associated with overexpression of AGR2 in K562DR cells. Luciferase reporter assay identified that miR-217 negatively regulated expression of AGR2 through binding the 3'-untranslated region of AGR2. Hypermethylation of the CpG island on the promoter region of the MIR217 gene is a probable reason for the downregulation of miR-217 in dasatinib-treated K562 cells. Forced expression of miR-217 led to decreased expression of AGR2 as well as compromised TKI-resistant potential of K562DR cells. Similarly, overexpression of miR-217 resensitized K562DR cells to dasatinib treatment in a murine xenograft transplantation model. TKI treatment-induced drug resistance is correlated with a decrease of miR-217 and upregulation of AGR2. The miR-217/AGR2 interaction might be a potential therapeutic target in treating CML patients with TKI resistance.


Assuntos
Antineoplásicos/farmacologia , Regulação Leucêmica da Expressão Gênica , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , MicroRNAs/fisiologia , Proteínas de Neoplasias/genética , Inibidores de Proteínas Quinases/farmacologia , Proteínas/genética , RNA Neoplásico/fisiologia , Regiões 3' não Traduzidas , Animais , Linhagem Celular Tumoral , Metilação de DNA , Dasatinibe/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Regulação Leucêmica da Expressão Gênica/genética , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Camundongos , Camundongos Endogâmicos NOD , MicroRNAs/biossíntese , MicroRNAs/genética , Proteínas de Neoplasias/metabolismo , Regiões Promotoras Genéticas , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas/metabolismo , RNA/metabolismo , Interferência de RNA , RNA Neoplásico/genética , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/farmacologia , Organismos Livres de Patógenos Específicos , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Blood ; 132(17): 1792-1804, 2018 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-30158248

RESUMO

Acute myeloid leukemia (AML) can evade the mouse and human innate immune system by suppressing natural killer (NK) cell development and NK cell function. This is driven in part by the overexpression of microRNA (miR)-29b in the NK cells of AML patients, but how this occurs is unknown. In the current study, we demonstrate that the transcription factor aryl hydrocarbon receptor (AHR) directly regulates miR-29b expression. We show that human AML blasts activate the AHR pathway and induce miR-29b expression in NK cells, thereby impairing NK cell maturation and NK cell function, which can be reversed by treating NK cells with an AHR antagonist. Finally, we show that inhibition of constitutive AHR activation in AML blasts lowers their threshold for apoptosis and decreases their resistance to NK cell cytotoxicity. Together, these results identify the AHR pathway as a molecular mechanism by which AML impairs NK cell development and function. The results lay the groundwork in establishing AHR antagonists as potential therapeutic agents for clinical development in the treatment of AML.


Assuntos
Regulação Leucêmica da Expressão Gênica/genética , Células Matadoras Naturais/imunologia , Leucemia Mieloide Aguda/imunologia , MicroRNAs/biossíntese , Receptores de Hidrocarboneto Arílico/metabolismo , Animais , Humanos , Células Matadoras Naturais/citologia , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Camundongos , Transdução de Sinais/fisiologia
18.
Mol Med Rep ; 18(2): 1766-1772, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29901125

RESUMO

Although hundreds of genes have been linked to chronic myelogenous leukemia (CML), many of the results lack reproducibility. In the present study, data across multiple modalities were integrated to evaluate 579 CML candidate genes, including literature­based CML­gene relation data, Gene Expression Omnibus RNA expression data and pathway­based gene­gene interaction data. The expression data included samples from 76 patients with CML and 73 healthy controls. For each target gene, four metrics were proposed and tested with case/control classification. The effectiveness of the four metrics presented was demonstrated by the high classification accuracy (94.63%; P<2x10­4). Cross metric analysis suggested nine top candidate genes for CML: Epidermal growth factor receptor, tumor protein p53, catenin ß 1, janus kinase 2, tumor necrosis factor, abelson murine leukemia viral oncogene homolog 1, vascular endothelial growth factor A, B­cell lymphoma 2 and proto­oncogene tyrosine­protein kinase. In addition, 145 CML candidate pathways enriched with 485 out of 579 genes were identified (P<8.2x10­11; q=0.005). In conclusion, weighted genetic networks generated using computational biology may be complementary to biological experiments for the evaluation of known or novel CML target genes.


Assuntos
Biologia Computacional , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Proteínas de Neoplasias/genética , Linhagem Celular Tumoral , Regulação Leucêmica da Expressão Gênica/genética , Redes Reguladoras de Genes/genética , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia
19.
Exp Hematol ; 64: 71-83.e8, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29733872

RESUMO

The BCR-ABL oncogene, the hallmark of chronic myeloid leukemia (CML), has been shown to activate several signaling pathways in leukemic cells. The natural history of this disease has been radically modified by tyrosine kinase inhibitors (TKIs). However, resistance to several lines of TKI therapies and progression to blast crisis (BC) remain significant concerns. To identify novel signaling pathways induced by BCR-ABL, we performed a transcriptome analysis in a BCR-ABL-expressing UT-7 cell line. More than 2000 genes differentially expressed between BCR-ABL-expressing and parental UT-7 cells were identified and ETS1 was found to be the most upregulated. ETS1 protein expression was also shown to be highly increased in UT-7 cells expressing BCR-ABL either constitutively or under the control of TET-inducible promoters. ETS1 expression is tyrosine-kinase dependent because it was reduced by TKIs. A significant increase of ETS1 messenger RNA (mRNA) expression was observed in blood cells from CML patients at diagnosis compared with healthy controls. Integration of publicly available chromatin immunoprecipitation sequencing and transcriptomic data with our results allowed us to identify potential ETS1 targets, some of which are involved in the progression of CML. The messenger RNA expression of two of these genes (DNM3 and LIMS1) was found to be associated with the absence of major cytogenetic response after 1 year of imatinib therapy. The present work demonstrates for the first time the involvement of the ETS1 transcriptional program in the experimental UT-7 model and a large cohort of CML patients.


Assuntos
Proteínas de Fusão bcr-abl/fisiologia , Regulação Leucêmica da Expressão Gênica/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Proteína Proto-Oncogênica c-ets-1/fisiologia , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Crise Blástica/genética , Linhagem Celular Tumoral , Estudos de Coortes , Progressão da Doença , Feminino , Proteínas de Fusão bcr-abl/antagonistas & inibidores , Perfilação da Expressão Gênica , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Humanos , Mesilato de Imatinib/farmacologia , Mesilato de Imatinib/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/enzimologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Masculino , Regiões Promotoras Genéticas/genética , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , RNA Mensageiro/biossíntese , RNA Mensageiro/sangue , RNA Neoplásico/biossíntese , RNA Neoplásico/sangue , Distribuição Aleatória , Transdução de Sinais , Transcriptoma
20.
Exp Hematol ; 64: 84-96, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29733873

RESUMO

RUNX1 is frequently mutated in T-cell acute lymphoblastic leukemia (T-ALL). The spectrum of RUNX1 mutations has led to the notion that it acts as a tumor suppressor in this context; however, other studies have placed RUNX1, along with transcription factors TAL1 and NOTCH1, as core drivers of an oncogenic transcriptional program. To reconcile these divergent roles, we knocked down RUNX1 in human T-ALL cell lines and deleted Runx1 or Cbfb in primary mouse T-cell leukemias. RUNX1 depletion consistently resulted in reduced cell proliferation and increased apoptosis. RUNX1 upregulated variable sets of target genes in each cell line, but consistently included a core set of oncogenic effectors including insulin-like growth factor 1 receptor (IGF1R) and NRAS. Our results support the conclusion that RUNX1 has a net positive effect on cell growth in the context of established T-ALL.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/fisiologia , Regulação Leucêmica da Expressão Gênica/genética , Proteínas de Neoplasias/fisiologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Animais , Divisão Celular , Linhagem Celular Tumoral , Tamanho Celular , Subunidade alfa 2 de Fator de Ligação ao Core/deficiência , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Subunidade beta de Fator de Ligação ao Core/deficiência , Subunidade beta de Fator de Ligação ao Core/genética , Deleção de Genes , Técnicas de Silenciamento de Genes , Xenoenxertos , Humanos , Leucemia Experimental/genética , Leucemia Experimental/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos SCID , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Interferência de RNA , RNA Interferente Pequeno/genética , Transcrição Genética , Transcriptoma , Carga Tumoral
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