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1.
Eur J Haematol ; 103(4): 417-425, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31356696

RESUMO

OBJECTIVES: This study explored resistance functions and their interactions in de novo AML treated with the "7 + 3" induction regimen. METHODS: We analyzed RNA-sequencing profiles of whole bone marrow samples from 52 de novo AML patients who completed the "7 + 3" regimen and stratified patients into CR (n = 35) and non-CR (n = 17) groups. RESULTS: A systematic gene set analysis revealed significant associations between chemoresistance and mTOR (P < .001), myc (P < .001), mitochondrial oxidative phosphorylation (P < .001), and stemness (P = .002). These functions were independent with regard to gene contents and activity scores. An integration of these four functions showed a prediction of chemoresistance (area under the receiver operating characteristic curve = 0.815) superior to that of each function alone. Moreover, our proposed seven-gene scoring system significantly correlated with the four-function model (r = .97; P < .001) to predict chemoresistance to the "7 + 3" regimen. On multivariate analysis, a seven-gene score of ≥-0.027 (hazard ratio: 11.18; 95% confidence interval: 2.06-60.65; P = .005) was an independent risk factor for induction failure. CONCLUSIONS: Myc, OXPHOS, mTOR, and stemness were responsive for chemoresistance in AML. Treatments other than the "7 + 3" regimen need to be considered for de novo AML patients predicted to be refractory to the "7 + 3" regimen.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/tratamento farmacológico , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Biomarcadores , Biomarcadores Tumorais , Células da Medula Óssea/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Perfilação da Expressão Gênica , Humanos , Quimioterapia de Indução , Leucemia Mieloide Aguda/genética , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Prognóstico , Curva ROC , Reprodutibilidade dos Testes , Resultado do Tratamento
2.
Blood ; 128(13): 1671-8, 2016 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-27421961

RESUMO

Most cancers evolve over time as patients initially responsive to therapy acquire resistance to the same drugs at relapse. Cancer stem cells have been postulated to represent a therapy-refractory reservoir for relapse, but formal proof of this model is lacking. We prospectively characterized leukemia stem cell populations (LSCs) from a well-defined cohort of patients with acute myelogenous leukemia (AML) at diagnosis and relapse to assess the effect of the disease course on these critical populations. Leukemic samples were collected from patients with newly diagnosed AML before therapy and after relapse, and LSC frequency was assessed by limiting dilution analyses. LSC populations were identified using fluorescent-labeled cell sorting and transplantation into immunodeficient NOD/SCID/interleukin 2 receptor γ chain null mice. The surface antigen expression profiles of pretherapy and postrelapse LSCs were determined for published LSC markers. We demonstrate a 9- to 90-fold increase in LSC frequency between diagnosis and relapse. LSC activity at relapse was identified in populations of leukemic blasts that did not demonstrate this activity before treatment and relapse. In addition, we describe genetic instability and exceptional phenotypic changes that accompany the evolution of these new LSC populations. This study is the first to characterize the evolution of LSCs in vivo after chemotherapy, identifying a dramatic change in the physiology of primitive AML cells when the disease progresses. Taken together, these findings provide a new frame of reference by which to evaluate candidate AML therapies in which both disease control and the induction of more advanced forms of disease should be considered.


Assuntos
Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/patologia , Células-Tronco Neoplásicas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Biomarcadores Tumorais/imunologia , Estudos de Coortes , Progressão da Doença , Feminino , Humanos , Imunofenotipagem , Leucemia Mieloide Aguda/imunologia , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Pessoa de Meia-Idade , Transplante de Neoplasias , Células-Tronco Neoplásicas/imunologia , Estudos Prospectivos , Recidiva , Adulto Jovem
3.
Bioact Mater ; 21: 241-252, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36157246

RESUMO

We propose an ex vivo T cell expansion system that mimics natural antigen-presenting cells (APCs) for adoptive cell therapy (ACT). Microfiber scaffolds coated with dendritic cell (DC) membrane replicate physicochemical properties of dendritic cells specific for T cell activation such as rapid recognition by T cells, long duration of T cell tethering, and DC-specific co-stimulatory cues. The DC membrane-coated scaffold is first surface-immobilized with T cell stimulatory ligands, anti-CD3 (αCD3) and anti-CD28 (αCD28) antibodies, followed by adsorption of releasable interleukin-2 (IL-2). The scaffolds present both surface and soluble cues to T cells ex vivo in the same way that these cues are presented by natural APCs in vivo. We demonstrate that the DC-mimicking scaffold promotes greater polyclonal expansion of primary human T cells as compared to αCD3/αCD28-functionalized Dynabead. More importantly, major histocompatibility complex molecules derived from the DC membrane of the scaffold allow antigen-specific T cell expansion with target cell-specific killing ability. In addition, most of the expanded T cells (∼97%) can be harvested from the scaffold by density gradient centrifugation. Overall, the DC-mimicking scaffold offers a scalable, modular, and customizable platform for rapid expansion of highly functional T cells for ACT.

4.
bioRxiv ; 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37066307

RESUMO

Mesenchymal stem/stromal cells (MSCs) within the bone marrow microenvironment (BMME) support normal hematopoietic stem and progenitor cells (HSPCs). However, the heterogeneity of human MSCs has limited the understanding of their contribution to clonal dynamics and evolution to myelodysplastic syndromes (MDS). We combined three MSC cell surface markers, CD271, VCAM-1 (Vascular Cell Adhesion Molecule-1) and CD146, to isolate distinct subsets of human MSCs from bone marrow aspirates of healthy controls (Control BM). Based on transcriptional and functional analysis, CD271+CD106+CD146+ (NGFR+/VCAM1+/MCAM+/Lin-; NVML) cells display stem cell characteristics, are compatible with murine BM-derived Leptin receptor positive MSCs and provide superior support for normal HSPCs. MSC subsets from 17 patients with MDS demonstrated shared transcriptional changes in spite of mutational heterogeneity in the MDS clones, with loss of preferential support of normal HSPCs by MDS-derived NVML cells. Our data provide a new approach to dissect microenvironment-dependent mechanisms regulating clonal dynamics and progression of MDS.

5.
Nat Commun ; 13(1): 5925, 2022 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-36207325

RESUMO

Periodontitis is a common type of inflammatory bone loss and a risk factor for systemic diseases. The pathogenesis of periodontitis involves inflammatory dysregulation, which represents a target for new therapeutic strategies to treat periodontitis. After establishing the correlation of cell-free DNA (cfDNA) level with periodontitis in patient samples, we test the hypothesis that the cfDNA-scavenging approach will benefit periodontitis treatment. We create a nanoparticulate cfDNA scavenger specific for periodontitis by coating selenium-doped hydroxyapatite nanoparticles (SeHANs) with cationic polyamidoamine dendrimers (PAMAM-G3), namely G3@SeHANs, and compare the activities of G3@SeHANs with those of soluble PAMAM-G3 polymer. Both G3@SeHANs and PAMAM-G3 inhibit periodontitis-related proinflammation in vitro by scavenging cfDNA and alleviate inflammatory bone loss in a mouse model of ligature-induced periodontitis. G3@SeHANs also regulate the mononuclear phagocyte system in a periodontitis environment, promoting the M2 over the M1 macrophage phenotype. G3@SeHANs show greater therapeutic effects than PAMAM-G3 in reducing proinflammation and alveolar bone loss in vivo. Our findings demonstrate the importance of cfDNA in periodontitis and the potential for using hydroxyapatite-based nanoparticulate cfDNA scavengers to ameliorate periodontitis.


Assuntos
Ácidos Nucleicos Livres , Dendrímeros , Periodontite , Selênio , Animais , Ácidos Nucleicos Livres/genética , Dendrímeros/farmacologia , Hidroxiapatitas , Camundongos , Periodontite/tratamento farmacológico
6.
Sci Adv ; 7(21)2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34138728

RESUMO

Leukemia stem cells (LSCs) sustain the disease and contribute to relapse in acute myeloid leukemia (AML). Therapies that ablate LSCs may increase the chance of eliminating this cancer in patients. To this end, we used a bioreducible lipidoid-encapsulated Cas9/single guide RNA (sgRNA) ribonucleoprotein [lipidoid nanoparticle (LNP)-Cas9 RNP] to target the critical gene interleukin-1 receptor accessory protein (IL1RAP) in human LSCs. To enhance LSC targeting, we loaded LNP-Cas9 RNP and the chemokine CXCL12α onto mesenchymal stem cell membrane-coated nanofibril (MSCM-NF) scaffolds mimicking the bone marrow microenvironment. In vitro, CXCL12α release induced migration of LSCs to the scaffolds, and LNP-Cas9 RNP induced efficient gene editing. IL1RAP knockout reduced LSC colony-forming capacity and leukemic burden. Scaffold-based delivery increased the retention time of LNP-Cas9 in the bone marrow cavity. Overall, sustained local delivery of Cas9/IL1RAP sgRNA via CXCL12α-loaded LNP/MSCM-NF scaffolds provides an effective strategy for attenuating LSC growth to improve AML therapy.


Assuntos
Sistemas CRISPR-Cas , Leucemia Mieloide Aguda , Edição de Genes , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/terapia , RNA Guia de Cinetoplastídeos/genética , Ribonucleoproteínas/genética , Microambiente Tumoral
7.
Adv Mater ; 32(46): e2003537, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33053221

RESUMO

Recent advances in CRISPR present attractive genome-editing toolsets for therapeutic strategies at the genetic level. Here, a liposome-coated mesoporous silica nanoparticle (lipoMSN) is reported as an effective CRISPR delivery system for multiplex gene-editing in the liver. The MSN provides efficient loading of Cas9 plasmid as well as Cas9 protein/guide RNA ribonucleoprotein complex (RNP), while liposome-coating offers improved serum stability and enhanced cell uptake. Hypothesizing that loss-of-function mutation in the lipid-metabolism-related genes pcsk9, apoc3, and angptl3 would improve cardiovascular health by lowering blood cholesterol and triglycerides, the lipoMSN is used to deliver a combination of RNPs targeting these genes. When targeting a single gene, the lipoMSN achieved a 54% gene-editing efficiency, besting the state-of-art Lipofectamine CRISPRMax. For multiplexing, lipoMSN maintained significant gene-editing at each gene target despite reduced dosage of target-specific RNP. By delivering combinations of targeting RNPs in the same nanoparticle, synergistic effects on lipid metabolism are observed in vitro and vivo. These effects, such as a 50% decrease in serum cholesterol after 4 weeks of post-treatment with lipoMSN carrying both pcsk9 and angptl3-targeted RNPs, could not be reached with a single gene-editing approach. Taken together, this lipoMSN represents a versatile platform for the development of efficient, combinatorial gene-editing therapeutics.


Assuntos
Portadores de Fármacos/química , Edição de Genes , Fígado/metabolismo , Proteína 3 Semelhante a Angiopoietina , Proteínas Semelhantes a Angiopoietina/genética , Sistemas CRISPR-Cas/genética , Técnicas de Transferência de Genes , Humanos , Lipídeos/química , Nanopartículas/química , Pró-Proteína Convertase 9/genética
8.
Cell Rep ; 27(1): 238-254.e6, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30943405

RESUMO

The NADPH-dependent oxidase NOX2 is an important effector of immune cell function, and its activity has been linked to oncogenic signaling. Here, we describe a role for NOX2 in leukemia-initiating stem cell populations (LSCs). In a murine model of leukemia, suppression of NOX2 impaired core metabolism, attenuated disease development, and depleted functionally defined LSCs. Transcriptional analysis of purified LSCs revealed that deficiency of NOX2 collapses the self-renewal program and activates inflammatory and myeloid-differentiation-associated programs. Downstream of NOX2, we identified the forkhead transcription factor FOXC1 as a mediator of the phenotype. Notably, suppression of NOX2 or FOXC1 led to marked differentiation of leukemic blasts. In xenotransplantation models of primary human myeloid leukemia, suppression of either NOX2 or FOXC1 significantly attenuated disease development. Collectively, these findings position NOX2 as a critical regulator of malignant hematopoiesis and highlight the clinical potential of inhibiting NOX2 as a means to target LSCs.


Assuntos
Autorrenovação Celular , Leucemia/sangue , Leucopoese , Células Progenitoras Mieloides/metabolismo , NADPH Oxidase 2/metabolismo , Animais , Células Cultivadas , Feminino , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Células HEK293 , Humanos , Leucemia/genética , Leucemia/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Células Progenitoras Mieloides/citologia , Células Progenitoras Mieloides/patologia , NADPH Oxidase 2/genética
9.
Adv Sci (Weinh) ; 5(7): 1700540, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30027026

RESUMO

CRISPR/Cas9 technology enables targeted gene editing; yet, the efficiency and specificity remain unsatisfactory, particularly for the nonvirally delivered, plasmid-based CRISPR/Cas9 system. To tackle this, a self-assembled micelle is developed and evaluated for human papillomavirus (HPV) E7 oncogene disruption. The optimized micelle enables effective delivery of Cas9 plasmid with a transient transgene expression profile, benefiting the specificity of Cas9 recognition. Furthermore, the feasibility of using the micelle is explored for another nucleic acid-guided nuclease system, Natronobacterium gregoryi Argonaute (NgAgo). Both systems are tested in vitro and in vivo to evaluate their therapeutic potential. Cas9-mediated E7 knockout leads to significant inhibition of HPV-induced cancerous activity both in vitro and in vivo, while NgAgo does not show significant E7 inhibition on the xenograft mouse model. Collectively, this micelle represents an efficient delivery system for nonviral gene editing, adding to the armamentarium of gene editing tools to advance safe and effective precision medicine-based therapeutics.

10.
Cell Stem Cell ; 20(3): 315-328.e7, 2017 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-28215825

RESUMO

Myeloid malignancy is increasingly viewed as a disease spectrum, comprising hematopoietic disorders that extend across a phenotypic continuum ranging from clonal hematopoiesis to myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). In this study, we derived a collection of induced pluripotent stem cell (iPSC) lines capturing a range of disease stages encompassing preleukemia, low-risk MDS, high-risk MDS, and secondary AML. Upon their differentiation, we found hematopoietic phenotypes of graded severity and/or stage specificity that together delineate a phenotypic roadmap of disease progression culminating in serially transplantable leukemia. We also show that disease stage transitions, both reversal and progression, can be modeled in this system using genetic correction or introduction of mutations via CRISPR/Cas9 and that this iPSC-based approach can be used to uncover disease-stage-specific responses to drugs. Our study therefore provides insight into the cellular events demarcating the initiation and progression of myeloid transformation and a new platform for testing genetic and pharmacological interventions.


Assuntos
Transformação Celular Neoplásica/patologia , Progressão da Doença , Células-Tronco Pluripotentes Induzidas/citologia , Leucemia Mieloide Aguda/patologia , Animais , Antineoplásicos/farmacologia , Transformação Celular Neoplásica/efeitos dos fármacos , Reprogramação Celular/efeitos dos fármacos , Reprogramação Celular/genética , Análise Mutacional de DNA , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Leucemia Mieloide Aguda/genética , Camundongos , Modelos Biológicos , Síndromes Mielodisplásicas/patologia , Transplante de Neoplasias , Fenótipo , Transcriptoma/efeitos dos fármacos , Transcriptoma/genética
11.
Nat Commun ; 7: 10739, 2016 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-26898884

RESUMO

Myelodysplastic syndromes (MDS) are driven by complex genetic and epigenetic alterations. The MSI2 RNA-binding protein has been demonstrated to have a role in acute myeloid leukaemia and stem cell function, but its role in MDS is unknown. Here, we demonstrate that elevated MSI2 expression correlates with poor survival in MDS. Conditional deletion of Msi2 in a mouse model of MDS results in a rapid loss of MDS haematopoietic stem and progenitor cells (HSPCs) and reverses the clinical features of MDS. Inversely, inducible overexpression of MSI2 drives myeloid disease progression. The MDS HSPCs remain dependent on MSI2 expression after disease initiation. Furthermore, MSI2 expression expands and maintains a more activated (G1) MDS HSPC. Gene expression profiling of HSPCs from the MSI2 MDS mice identifies a signature that correlates with poor survival in MDS patients. Overall, we identify a role for MSI2 in MDS representing a therapeutic target in this disease.


Assuntos
Síndromes Mielodisplásicas/metabolismo , Proteínas de Ligação a RNA/metabolismo , Idoso , Animais , Estudos de Casos e Controles , Modelos Animais de Doenças , Feminino , Células-Tronco Hematopoéticas/fisiologia , Humanos , Leucemia Mieloide Aguda/etiologia , Leucemia Mieloide Aguda/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Síndromes Mielodisplásicas/etiologia , Síndromes Mielodisplásicas/mortalidade
14.
J Agric Food Chem ; 56(14): 5806-12, 2008 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-18582084

RESUMO

Water hyacinth ( Eichhornia crassipes) is a rapid-growing freshwater vascular plant that has been used to remove heavy metals in contaminated water. But the transportation and distribution of the absorbed heavy metal in the plant are not clear. In this study, water hyacinth was exposed to cadmium (Cd, 10 microM, pulse) and then transferred to a Cd-free solution (chase). The Cd content in the tissues was measured, and the Cd-binding complexes were isolated and identified. We found that (1) in two days, up to 80% of the Cd in the solution was absorbed by the plant, and the Cd could not be released back to the growth solution in the chase period; (2) approximately 1 mg of Cd was accumulated in the water hyacinth/g of dry weight in this condition; (3) invading Cd was bound rapidly as the low-molecular-weight (LMW) complex serving as the transient form for further sequestration; (4) the LMW complex in water hyacinth contained no phytochelatins and was different from the LMW complex in fission yeast; (5) the Cd absorbed in the plant was essentially stored in the high-molecular-weight (HMW) form after 1 week; (6) a small fraction of the absorbed Cd was found in the upper part of the plant (stem and leaves) in the form of complexes; (7) the HMW complex was composed of phytochelatins PC 3 and PC 4 primarily, with only a small amount of PC 2; (8) a rare PC-related peptide was found in the HMW complex that might be derived from PC 3. These observations contribute to the further understanding of water hyacinth in serving as an efficient and reliable accumulator for heavy metals.


Assuntos
Cádmio/metabolismo , Eichhornia/metabolismo , Fitoquelatinas/metabolismo , Absorção , Aminoácidos/análise , Transporte Biológico , Cádmio/análise , Eichhornia/química , Peso Molecular , Fitoquelatinas/química , Folhas de Planta/química , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Caules de Planta/química
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