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Acute myeloid leukemia (AML) is an aggressive leukemic malignancy that affects myeloid lineage progenitors. Relapsed or refractory AML patients continue to have poor prognoses, necessitating the development of novel therapy alternatives. Adoptive T-cell therapy with chimeric antigen receptors (CARs) is an intriguing possibility in the field of leukemia treatment. Chimeric antigen receptor T-cell therapy is now being tested in clinical trials (mostly in phase I and phase II) using AML targets including CD33, CD123, and CLL-1. Preliminary data showed promising results. However, due to the cellular and molecular heterogeneity of AML and the co-expression of some AML targets on hematopoietic stem cells, these clinical investigations have shown substantial "on-target off-tumor" toxicities, indicating that more research is required. In this review, the latest significant breakthroughs in AML CAR T cell therapy are presented. Furthermore, the limitations of CAR T-cell technology and future directions to overcome these challenges are discussed.
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Imunoterapia Adotiva , Leucemia Mieloide Aguda , Receptores de Antígenos Quiméricos , Humanos , Leucemia Mieloide Aguda/terapia , Leucemia Mieloide Aguda/imunologia , Receptores de Antígenos Quiméricos/imunologia , Imunoterapia Adotiva/métodos , Linfócitos T/imunologia , Linfócitos T/transplanteRESUMO
Background/objective: The practice of complementary and alternative medicine has significantly gained acceptance worldwide, such as Al-Hijama, also known as cupping therapy. Despite the growing popularity of therapeutic cupping among athletes, little is known about the impact of cupping therapy on sports fields. The current study was designed to explore the effect of wet cupping therapy on the haematological and inflammatory parameters in Jordanian national team players. Methods: The procedure was carried out at a specialized centre for cupping in Amman on the morning of the 19th Rajab. The data were obtained from 14 healthy male participants aged between 21 and 22 years. The haematological and inflammatory parameters were assessed by comparing venous blood components before and after four weeks of wet cupping. Results: Complete blood count (CBC) analysis of venous blood samples four weeks after wet cupping showed a significant increase in the values of total white blood cells (WBCs), neutrophils, lymphocytes, red blood cells (RBCs), haematocrit, and haemoglobin as compared with venous blood samples before cupping. Blood film examination of venous blood samples post-cupping revealed normocytic normochromic RBCs; WBCs and platelets were unremarkable. Analysis of inflammatory markers post cupping showed a significant decrease in the monocyte/lymphocyte ratio (MLR) and platelet/lymphocyte ratio (PLR) but no differences in neutrophil/lymphocyte ratio (NLR). Conclusion: The findings of this study suggest that wet cupping has an indispensable influence on haematological and immunological parameters in athletes, where it reinforces cellular immunity, generates younger blood cells, and reduces inflammation markers. It is probable, therefore, that cupping improves sports performance and achievement. The evidence from this research adds to a growing body of literature on cupping therapy in sports.
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Emerging evidence implicates the epithelial-mesenchymal transition transcription factor Zeb1 as a critical regulator of hematopoietic stem cell (HSC) differentiation. Whether Zeb1 regulates long-term maintenance of HSC function remains an open question. Using an inducible Mx-1-Cre mouse model that deletes conditional Zeb1 alleles in the adult hematopoietic system, we found that mice engineered to be deficient in Zeb1 for 32 weeks displayed expanded immunophenotypically defined adult HSCs and multipotent progenitors associated with increased abundance of lineage-biased/balanced HSC subsets and augmented cell survival characteristics. During hematopoietic differentiation, persistent Zeb1 loss increased B cells in the bone marrow and spleen and decreased monocyte generation in the peripheral blood. In competitive transplantation experiments, we found that HSCs from adult mice with long-term Zeb1 deletion displayed a cell autonomous defect in multilineage differentiation capacity. Long-term Zeb1 loss perturbed extramedullary hematopoiesis characterized by increased splenic weight and a paradoxical reduction in splenic cellularity that was accompanied by HSC exhaustion, lineage-specific defects, and an accumulation of aberrant, preleukemic like c-kit+CD16/32+ progenitors. Loss of Zeb1 for up to 42 weeks can lead to progressive splenomegaly and an accumulation of Gr-1+Mac-1+ cells, further supporting the notion that long-term expression of Zeb1 suppresses preleukemic activity. Thus, sustained Zeb1 deletion disrupts HSC functionality in vivo and impairs regulation of extramedullary hematopoiesis with potential implications for tumor suppressor functions of Zeb1 in myeloid neoplasms.
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Hematopoese Extramedular , Células-Tronco Hematopoéticas , Homeobox 1 de Ligação a E-box em Dedo de Zinco , Animais , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo , Camundongos , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/patologia , Hematopoese Extramedular/genética , Diferenciação Celular , Camundongos Knockout , Baço/metabolismo , Baço/patologia , Baço/citologia , Células-Tronco Adultas/metabolismo , Linhagem da CélulaRESUMO
Colon cancer (CC) is a significant cause of death worldwide, particularly in Saudi Arabia. To increase the accuracy of diagnosis and treatment, it is important to discover new specific biomarkers for CC. The main objectives of this research are to identify potential specific biomarkers for the early diagnosis of CC by analyzing the expressions of eight cancer testis (CT) genes, as well as to analyze how epigenetic mechanisms control the expression of these genes in CC cell lines. Tissue samples were collected from 15 male patients with CC tissues and matched NC tissues for gene expression analysis. The expression levels of specific CT genes, including ADAD1, DMRTC2, PRSS54, SYCE1, SYCP1, TEX101, TEX48, and TMPRSS12, were assessed using quantitative techniques. To validate the gene expression patterns, we used publicly available CC statistics. To investigate the effect of inhibition of DNA methylation and histone deacetylation on CT gene expression, in vitro experiments were performed using HCT116 and Caco-2 cell lines. There was no detected expression of the genes neither in the patient samples nor in NC tissues, except for TEX48, which exhibited upregulation in CC samples compared to NC tissues in online datasets. Notably, CT genes showed expression in testis samples. In vitro, experiments demonstrated significant enhancement in mRNA expression levels of ADAD1, DMRTC2, PRSS54, SYCE1, SYCP1, TEX101, TEX48, and TMPRSS12 following treatment with 5-aza-2'-deoxycytidine and trichostatin A in HCT116 and Caco-2 cell lines. Epigenetic treatments modify the expression of CT genes, indicating that these genes can potentially be used as biomarkers for CC. The importance of conducting further research to understand and target epigenetic mechanisms to improve CC treatment cannot be overemphasized.
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Neoplasias do Colo , Metilação de DNA , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias do Colo/genética , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Masculino , Epigênese Genética/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células CACO-2 , Metilação de DNA/efeitos dos fármacos , Células HCT116 , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Azacitidina/farmacologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Pessoa de Meia-Idade , Ácidos Hidroxâmicos/farmacologia , Decitabina/farmacologiaRESUMO
BACKGROUND: Recurrent pregnancy Loss (RPL) is common problem affecting many couples. A certain genetic variants link to increase the danger of this condition particularly HPA-1, HPA-3 and Human Factor XIII Val34Leu Mutation. The present study aims to find an association between RPL and the Factor XIII Val34Leu polymorphism, as well as HPA-1 and HPA-3 in Sudanese women with RPL. METHODS: This case-control study conducted between June 2022 and December 2022 included 216 women, with 103 cases having minimum three abortions in the past, and 113 healthy controls with at least two full-term births and no abortion history. DNA was isolated from whole blood and the status of three genetic polymorphisms (HPA-1, HPA-3, and factor XIII) was done using a polymerase chain reaction (PCR). Data was analysed using the SPSS version 24 software. RESULTS: The A/A genotype was found to be more prevalent in cases (79.6%) and controls (96.5%) regarding HPA-1. A significant difference was observed in overall allele frequency for B allele (97.0%) and expected frequency of A allele was (81.1%) using the Hardy-Weinberg distribution (p < 0.001). The genotype A/A was most common in these patients (90.3%) and controls (100%), while B/B genotype was only (9.7%) in patients regarding HPA-3. Furthermore, the frequency of Val/Val genotype was higher in cases (88.3%) as compared with controls (90.3%). The risk of RPL in patients was nearly the same in Val/Leu individuals and controls group but all these differences were not statistically significant (p > 0.05). CONCLUSION: Our results indicate a link between Human Platelet Antigen-1 (HPA-1), Human Platelet Antigen-3 (HPA-3) and Factor XIII gene polymorphism with RPL.
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Aborto Habitual , Antígenos de Plaquetas Humanas , Gravidez , Humanos , Feminino , Fator XIII/genética , Antígenos de Plaquetas Humanas/genética , Estudos de Casos e Controles , Polimorfismo Genético , Mutação , Aborto Habitual/genéticaRESUMO
Hospital and municipal wastewater contribute to the spread of antibiotic-resistant bacteria and genes in the environment. This study aimed to examine the antibiotic resistance and ß-lactamase production in clinically significant Gram-negative bacteria isolated from hospital and municipal wastewater. The susceptibility of bacteria to antibiotics was tested using the disk diffusion method, and the presence of extended-spectrum ß-lactamases (ESBL) and carbapenemases was determined using an enzyme inhibitor and standard multiplex PCR. Analysis of antimicrobial resistance of total bacterial strains (n = 23) revealed that most of them were resistant to cefotaxime (69.56%), imipenem (43.47%), meropenem (47.82%) and amoxicillin-clavulanate (43.47%), gentamicin (39.13%), cefepime and ciprofloxacin (34.78%), trimethoprim-sulfamethoxazole (30.43%). A total of 8 of 11 phenotypically confirmed isolates were found to have ESBL genes. The blaTEM gene was present in 2 of the isolates, while the blaSHV gene was found in 2 of the isolates. Furthermore, the blaCTX-M gene was found in 3 of the isolates. In one isolate, both the blaTEM and blaSHV genes were identified. Furthermore, of the 9 isolates that have been phenotypically confirmed to have carbapenemase, 3 were confirmed by PCR. Specifically, 2 isolates have the blaOXA-48 type gene and 1 have the blaNDM-1 gene. In conclusion, our investigation shows that there is a significant rate of bacteria that produce ESBL and carbapenemase, which can promote the spread of bacterial resistance. Identifying ESBL and carbapenemase production genes in wastewater samples and their resistance patterns can provide valuable data and guide the development of pathogen management strategies that could potentially help reduce the occurrence of multidrug resistance.
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Zeb1, a zinc finger E-box binding homeobox epithelial-mesenchymal (EMT) transcription factor, acts as a critical regulator of hematopoietic stem cell (HSC) self-renewal and multi-lineage differentiation. Whether Zeb1 directly regulates the function of multi-potent progenitors primed for hematopoietic lineage commitment remains ill defined. By using an inducible Mx-1 Cre conditional mouse model where Zeb1 was genetically engineered to be deficient in the adult hematopoietic system (hereafter Zeb1-/-), we found that the absolute cell number of immunophenotypically defined lympho-myeloid primed progenitors (LMPPs) from Zeb1-/- mice was reduced. Myeloid- and lymphoid-biased HSCs in Zeb1-/- mice were unchanged, implying that defective LMPP generation from Zeb1-/- mice was not directly caused by an imbalance of lineage-biased HSCs. Functional analysis of LMPP from Zeb1-/- mice, as judged by competitive transplantation, revealed an overall reduction in engraftment to hematopoietic organs over 4 weeks, which correlated with minimal T-cell engraftment, reduced B-cell and monocyte/macrophage engraftment, and unperturbed granulocyte engraftment. Thus, Zeb1 regulates LMPP differentiation potential to select lympho-myeloid lineages in the context of transplantation.
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The failure to treat infectious diseases due to the continual emergence of drug-resistant microbes poses a huge and serious challenge for human health globally. Currently, the discovery and development of natural therapeutic compounds are attracting considerable attention from researchers worldwide. In this project, two types of pollen grains (maize and clover) were evaluated for potential antimicrobial activities. Extracts of both pollen grains were purified using HPLC, which has been shown to have numerous phenolic and flavonoid compounds. Pyro catechol and methyl gallate were detected in high concentrations (1145.56 and 1056.57 µg/mL, respectively) in the maize extract, while caffeic acid, quercetin, and kaempferol (464.73, 393.05, and 390.93 µg/mL, respectively) were among the compounds observed at high concentrations in the clover pollen grains extract. Staphylococcus aureus, Escherichia coli, Salmonella typhi, and Candida albicans were more sensitive to the clover pollen grains extract with inhibition zones of 22 ± 0.2, 18 ± 0.1, 29 ± 0.3, and 42 ± 0.4 mm compared to the size of the inhibitory zones caused by the maize pollen grains extract (19 ± 0.3, 15 ± 0.4, 27 ± 0.1, and 22 ± 0.4 mm, respectively). Moreover, lower MIC values for the clover pollen grains extract were recorded against C. albicans (1.97 ± 0.04 µg/mL), S. aureus (62.5 ± 1.00 µg/mL), and E. coli (62.5 ± 0.07 µg/mL) than the MICs caused by the maize pollen grains extract. The use of a transmission electron microscope revealed that the E. coli that had been treated with the clover pollen grains extract showed changes in its cell walls compared to that treated with the maize pollen grains extract. The clover pollen grains extract exhibited a stronger antioxidant potential, with an IC50 value of 22.18 µg/mL, compared to an IC50 value of 54.85 µg/mL for the maize pollen grains extract, via a DPPH scavenging assay. Regarding anticancer activity, the maize pollen grains extract was revealed to be more effective in terms of inhibiting the human colon cancer cell line HCT-116, with an IC50 value of 67.02 ± 1.37 µg/mL, compared with the observed toxicity caused by the clover extract, with an IC50 value of 75.03 ± 1.02 µg/mL. Overall, the clover pollen grains extract demonstrated potent antibacterial and antioxidant activities, but not anticancer activity, when compared to the maize grains extract. Thus, the current findings related to both types of pollen grains (clover and maize) highlight their potential therapeutic applications for the treatment of certain infectious diseases and malignancies.
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Background: A genetic polymorphism that causes abnormal folate metabolism may lead to genomic instability and increase susceptibility to malignancies such as Acute Lymphoblastic leukemia (ALL). The purpose of this research is to identify methylene tetrahydrofolate reductase (MTHFR C677T) (NCBI ID: 4524) mutation in ALL patients. Methods: The study was a descriptive case-control hospital-based study with one hundred Sudanese participants divided equally into fifty (50) Sudanese ALL diagnosed patients as cases and fifty (50) Sudanese individuals as controls. The MTHFR C677T mutant allele was detected using conventional PCR, with the primer sequence of MTHFR C677T F-TGAAGGAAGGTGTCTGCGGGA R-AGGACGGTGCGGTGAGAGTG. The study was conducted from January to March 2023, and samples were collected from the Radiation and Isotops Center at Khartoum Hospital. Results: The investigation revealed that 12 of the 50 patients in the case group (24%) had the MTHFR C677T mutant allele, and the study also revealed that there is significant correlation with the control group. There is no significant relationship between socio-demographic variables and MTHFR mutation detection in ALL patients. Also, the sociodemographic variables predictors of MTHFR mutation among ALL patients adjusted for smoking habit revealed no significant relationship. Conclusion: According to the findings of this study, the mutant allele of the Methylene Tetra Hydro Folate Reductase C677T was detected and demonstrated varying degrees of significance. It was concluded that the MTHFR C677T gene mutation was associated with acute lymphoblastic leukemia in Sudanese patients.
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Antimicrobial resistance (AMR) is a critical issue in health care in terms of mortality, quality of services, and financial damage. In the battle against AMR, it is crucial to recognize the impacts of all four domains, namely, mankind, livestock, agriculture, and the ecosystem. Many sociocultural and financial practices that are widespread in the world have made resistance management extremely complicated. Several pathways, including hospital effluent, agricultural waste, and wastewater treatment facilities, have been identified as potential routes for the spread of resistant bacteria and their resistance genes in soil and surrounding ecosystems. The overuse of uncontrolled antibiotics and improper treatment and recycled wastewater are among the contributors to AMR. Health-care organizations have begun to address AMR, although they are currently in the early stages. In this review, we provide a brief overview of AMR development processes, the worldwide burden and drivers of AMR, current knowledge gaps, monitoring methodologies, and global mitigation measures in the development and spread of AMR in the environment.
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Advancing age causes physiologic decline in tissue function. In the hematopoietic system this manifests as a progressive reduction in blood or immune cell function and clonal hematopoiesis, where a mutated hematopoietic stem cell can dominate blood cell production and confer an increased propensity for myeloid malignancy. In the aging cardiovascular system, atherosclerosis causes an inflammatory cell- driven accumulation of lipid-derived plaques in major arteries which constrains blood flow and can lead to myocardial infarction and stroke. Clonal hematopoiesis in the elderly has recently been associated with a substantially increased risk of atherosclerosis-related cardiovascular disease. However, the direct association between deregulated hematopoiesis in clonal hematopoiesis and atherosclerosis is poorly defined. Herein, we describe a flow cytometry method to prospectively analyze the crucial hematopoietic stem/progenitor, inflammatory and lymphoid cell participants in atherosclerosis. This analysis can be applied to decipher the complex relationship between hematopoietic cell types involved in clonal hematopoiesis and atherosclerosis in mouse models.
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Aterosclerose , Células-Tronco Hematopoéticas , Animais , Aterosclerose/patologia , Células Sanguíneas/metabolismo , Citometria de Fluxo , Hematopoese , Células-Tronco Hematopoéticas/metabolismo , CamundongosRESUMO
Lymphomas are heterogeneous malignant tumours of white blood cells characterised by the aberrant proliferation of mature lymphoid cells or their precursors. Lymphomas are classified into main types depending on the histopathologic evidence of biopsy taken from an enlarged lymph node, progress stages, treatment strategies, and outcomes: Hodgkin and non-Hodgkin lymphoma (NHL). Moreover, lymphomas can be further divided into subtypes depending on the cell origin, and immunophenotypic and genetic aberrations. Many factors play vital roles in the progression, pathogenicity, incidence, and mortality rate of lymphomas. Among NHLs, peripheral T cell lymphomas (PTCLs) are rare lymphoid malignancies, that have various cellular morphology and genetic mutations. The clinical presentations are usually observed at the advanced stage of the disease. Many recent studies have reported that the expressions of NOTCH1, GATA3, and c-MYC are associated with poorer prognosis in PTCL and are involved in downstream activities. However, questions have been raised about the pathological relationship between these factors in PTCLs. Therefore, in this review, we investigate the role and relationship of the NOTCH1 pathway, transcriptional factor GATA3 and proto-oncogene c-MYC in normal T cell development and malignant PTCL subtypes.
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During aging, hematopoietic stem cell (HSC) function wanes with important biological and clinical implications for benign and malignant hematology, and other comorbidities, such as cardiovascular disease. However, the molecular mechanisms regulating HSC aging remain incompletely defined. GATA2 haploinsufficiency driven clinical syndromes initially result in primary immunodeficiencies and routinely evolve into hematologic malignancies on acquisition of further epigenetic mutations in both young and older patients. Using a conditional mouse model of Gata2 haploinsufficiency, we discover that during aging Gata2 promotes HSC proliferation, monocytosis, and loss of the common lymphoid progenitor. Aging of Gata2 haploinsufficient mice also offsets enhanced HSC apoptosis and decreased granulocyte-macrophage progenitor number normally observed in young Gata2 haploinsufficient mice. Transplantation of elderly Gata2 haploinsufficient HSCs impairs HSC function with evidence of myeloid bias. Our data demonstrate that Gata2 regulates HSC aging and suggest the mechanisms by which Gata2 mediated HSC aging has an impact on the evolution of malignancies in GATA2 haploinsufficiency syndromes.
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Deficiência de GATA2 , Idoso , Envelhecimento/genética , Animais , Proliferação de Células , Fator de Transcrição GATA2/genética , Hematopoese , Células-Tronco Hematopoéticas , Humanos , CamundongosRESUMO
Atherosclerosis, an inflammatory disorder of the vasculature and the underlying cause of cardiovascular disease, is responsible for one in three global deaths. Consumption of active food ingredients such as omega-3 polyunsaturated fatty acids, flavanols and phytosterols has many beneficial effects on cardiovascular disease. However, their combined actions on the risk factors for atherosclerosis remains poorly understood. We have previously shown that a formulation containing each of these active components at physiologically relevant doses modulated several monocyte/macrophage processes associated with atherosclerosis in vitro, including inhibition of cytokine-induced pro-inflammatory gene expression, chemokine-driven monocyte migration, expression of M1 phenotype markers, and promotion of cholesterol efflux. The objectives of the present study were to investigate whether the protective actions of the formulation extended in vivo and to delineate the potential underlying mechanisms. The formulation produced several favourable changes, including higher plasma levels of HDL and reduced levels of macrophages and myeloid-derived suppressor cells in the bone marrow. The mRNA expression of liver-X-receptor-α, peroxisome proliferator-activated receptor-γ and superoxide dismutase-1 was induced in the liver and that of interferon-γ and the chemokine (C-X-C motif) ligand 1 decreased, thereby suggesting the potential mechanisms for many beneficial effects. Other changes were also observed such as increased plasma levels of triglycerides and lipid peroxidation that may reflect potential activation of brown fat. This study provides new insights into the protective actions and the potential underlying mechanisms of the formulation in vivo, particularly in relation to risk factors together with changes in systemic inflammation and hepatic lipid alterations associated with atherosclerosis and metabolic syndrome, and supports further assessments in human trials.
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Cardiotônicos/farmacologia , Doença da Artéria Coronariana/prevenção & controle , Animais , Cardiotônicos/administração & dosagem , Dieta Hiperlipídica , Modelos Animais de Doenças , Ácidos Graxos Ômega-3/administração & dosagem , Flavanonas/administração & dosagem , Alimento Funcional , Expressão Gênica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fitosteróis/administração & dosagem , Fatores de RiscoRESUMO
Zeb1, a zinc finger E-box binding homeobox epithelial-mesenchymal transition (EMT) transcription factor, confers properties of "stemness," such as self-renewal, in cancer. Yet little is known about the function of Zeb1 in adult stem cells. Here, we used the hematopoietic system as a well-established paradigm of stem cell biology to evaluate Zeb1-mediated regulation of adult stem cells. We employed a conditional genetic approach using the Mx1-Cre system to specifically knock out (KO) Zeb1 in adult hematopoietic stem cells (HSCs) and their downstream progeny. Acute genetic deletion of Zeb1 led to rapid-onset thymic atrophy and apoptosis-driven loss of thymocytes and T cells. A profound cell-autonomous self-renewal defect and multilineage differentiation block were observed in Zeb1-KO HSCs. Loss of Zeb1 in HSCs activated transcriptional programs of deregulated HSC maintenance and multilineage differentiation genes and of cell polarity consisting of cytoskeleton-, lipid metabolism/lipid membrane-, and cell adhesion-related genes. Notably, epithelial cell adhesion molecule (EpCAM) expression was prodigiously upregulated in Zeb1-KO HSCs, which correlated with enhanced cell survival, diminished mitochondrial metabolism, ribosome biogenesis, and differentiation capacity and an activated transcriptomic signature associated with acute myeloid leukemia (AML) signaling. ZEB1 expression was downregulated in AML patients, and Zeb1 KO in the malignant counterparts of HSCs - leukemic stem cells (LSCs) - accelerated MLL-AF9- and Meis1a/Hoxa9-driven AML progression, implicating Zeb1 as a tumor suppressor in AML LSCs. Thus, Zeb1 acts as a transcriptional regulator in hematopoiesis, critically coordinating HSC self-renewal, apoptotic, and multilineage differentiation fates required to suppress leukemic potential in AML.
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Células-Tronco Hematopoéticas/metabolismo , Leucemia Mieloide Aguda/metabolismo , Células-Tronco Neoplásicas/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo , Animais , Deleção de Genes , Células-Tronco Hematopoéticas/patologia , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Camundongos , Camundongos Knockout , Células-Tronco Neoplásicas/patologia , Proteínas Supressoras de Tumor/genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genéticaRESUMO
Subversion of transcription factor (TF) activity in hematopoietic stem/progenitor cells (HSPCs) leads to the development of therapy-resistant leukemic stem cells (LSCs) that drive fulminant acute myeloid leukemia (AML). Using a conditional mouse model where zinc-finger TF Gata2 was deleted specifically in hematopoietic cells, we show that knockout of Gata2 leads to rapid and complete cell-autonomous loss of adult hematopoietic stem cells. By using short hairpin RNAi to target GATA2, we also identify a requirement for GATA2 in human HSPCs. In Meis1a/Hoxa9-driven AML, deletion of Gata2 impedes maintenance and self-renewal of LSCs. Ablation of Gata2 enforces an LSC-specific program of enhanced apoptosis, exemplified by attenuation of anti-apoptotic factor BCL2, and re-instigation of myeloid differentiation--which is characteristically blocked in AML. Thus, GATA2 acts as a critical regulator of normal and leukemic stem cells and mediates transcriptional networks that may be exploited therapeutically to target key facets of LSC behavior in AML.