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1.
Genes Dev ; 36(9-10): 582-600, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35654454

RESUMO

One of the mechanisms by which cancer cells acquire hyperinvasive and migratory properties with progressive loss of epithelial markers is the epithelial-to-mesenchymal transition (EMT). We have previously reported that in different cancer types, including nonsmall cell lung cancer (NSCLC), the microRNA-183/96/182 cluster (m96cl) is highly repressed in cells that have undergone EMT. In the present study, we used a novel conditional m96cl mouse to establish that loss of m96cl accelerated the growth of Kras mutant autochthonous lung adenocarcinomas. In contrast, ectopic expression of the m96cl in NSCLC cells results in a robust suppression of migration and invasion in vitro, and tumor growth and metastasis in vivo. Detailed immune profiling of the tumors revealed a significant enrichment of activated CD8+ cytotoxic T lymphocytes (CD8+ CTLs) in m96cl-expressing tumors, and m96cl-mediated suppression of tumor growth and metastasis was CD8+ CTL-dependent. Using coculture assays with naïve immune cells, we show that m96cl expression drives paracrine stimulation of CD8+ CTL proliferation and function. Using tumor microenvironment-associated gene expression profiling, we identified that m96cl elevates the interleukin-2 (IL2) signaling pathway and results in increased IL2-mediated paracrine stimulation of CD8+ CTLs. Furthermore, we identified that the m96cl modulates the expression of IL2 in cancer cells by regulating the expression of transcriptional repressors Foxf2 and Zeb1, and thereby alters the levels of secreted IL2 in the tumor microenvironment. Last, we show that in vivo depletion of IL2 abrogates m96cl-mediated activation of CD8+ CTLs and results in loss of metastatic suppression. Therefore, we have identified a novel mechanistic role of the m96cl in the suppression of lung cancer growth and metastasis by inducing an IL2-mediated systemic CD8+ CTL immune response.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , MicroRNAs , Animais , Linfócitos T CD8-Positivos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Interleucina-2/genética , Interleucina-2/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , Linfócitos T Citotóxicos , Microambiente Tumoral
2.
Bioinformatics ; 39(1)2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36440915

RESUMO

SUMMARY: The NanoTube is an open-source pipeline that simplifies the processing, quality control, normalization and analysis of NanoString nCounter gene expression data. It is implemented in an extensible R library, which performs a variety of gene expression analysis techniques and contains additional functions for integration with other R libraries performing advanced NanoString analysis techniques. Additionally, the NanoTube web application is available as a simple tool for researchers without programming expertise. AVAILABILITY AND IMPLEMENTATION: The NanoTube R package is available on Bioconductor under the GPL-3 license (https://www.bioconductor.org/packages/NanoTube/). The R-Shiny application can be downloaded at https://github.com/calebclass/Shiny-NanoTube, or a simplified version of this application can be run on all major browsers, at https://research.butler.edu/nanotube/. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Nanotubos , Software , Perfilação da Expressão Gênica , Biblioteca Gênica , Controle de Qualidade
3.
Mod Pathol ; 35(9): 1212-1219, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35504958

RESUMO

EZH2 coding mutation (EZH2MUT), resulting in loss-of-function, is an independent predictor of overall survival in MDS. EZH2 function can be altered by other mechanisms including copy number changes, and mutations in other genes and non-coding regions of EZH2. Assessment of EZH2 protein can identify alterations of EZH2 function missed by mutation assessment alone. Precise evaluation of EZH2 function and gene-protein correlation in clinical MDS cohorts is important in the context of upcoming targeted therapies aimed to restore EZH2 function. In this study, we evaluated the clinicopathologic characteristics of newly diagnosed MDS patients with EZH2MUT and correlated the findings with protein expression using immunohistochemistry. There were 40 (~6%) EZH2MUT MDS [33 men, seven women; median age 74 years (range, 55-90)]. EZH2 mutations spanned the entire coding region. Majority had dominant EZH2 clone [median VAF, 30% (1-92)], frequently co-occurring with co-dominant TET2 (38%) and sub-clonal ASXL1 (55%) and RUNX1 (43%) mutations. EZH2MUT MDS showed frequent loss-of-expression compared to EZH2WT (69% vs. 27%, p = 0.001). Interestingly, NINE (23%) EZH2WT MDS also showed loss-of-expression. EZH2MUT and loss-of-expression significantly associated with male predominance and chr(7) loss. Further, only EZH2 loss-of-expression patients showed significantly lower platelet counts, a trend for higher BM blast% and R-IPSS scores. Over a 14-month median follow-up, both EZH2MUT (p = 0.027) and loss-of-expression (p = 0.0063) correlated with poor survival, independent of R-IPSS, age and gender. When analyzed together, loss-of-expression showed a stronger correlation than mutation (p = 0.061 vs. p = 0.43). In conclusion, immunohistochemical assessment of EZH2 protein, alongside mutation, is important for prognostic workup of MDS.


Assuntos
Proteína Potenciadora do Homólogo 2 de Zeste , Síndromes Mielodisplásicas , Idoso , Idoso de 80 Anos ou mais , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Síndromes Mielodisplásicas/patologia , Prognóstico , Fatores de Transcrição/genética
4.
Am J Hematol ; 95(6): 612-622, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32112433

RESUMO

Acute myeloid leukemia with myelodysplasia-related changes (AML-MRC) is a heterogeneous disorder defined by multilineage dysplasia, myelodysplastic syndrome (MDS)-related karyotype, or history of prior MDS. We evaluated 415 patients with AML-MRC treated from 2013 to 2018 and analyzed their clinical outcomes based on the diagnostic criteria of AML-MRC, therapy type and mutation profile. Criteria for AML-MRC included: cytogenetic abnormalities (AML-MRC-C) in 243 (59%), prior history of MDS in 75 (18%) including 47 (11%) with previously untreated MDS (AML-MRC-H) and 28 (7%) with previously treated MDS (AML-MRC-TS), and 97 (23%) with multilineage dysplasia (AML-MRC-M). Median age was 70 years (range 18-94). Among 95 evaluable patients, a total of 37 (39%) had secondary-type (ASXL1, BCOR, EZH2, SF3B1, SRSF2, STAG2, U2AF1, ZRSR2) mutations. Mutations in ASXL1, BCOR, SF3B1, SRSF2, and U2AF1 tended to appear in dominant clones. By multivariate analysis, AML-MRC subtype, age and serum LDH levels were independent predictors of outcome, with patients with AML-MRC-M (HR 0.56, CI 0.38-0.84, P = .004) and AML-MRC-H having better OS. Compared to a cohort of 468 patients with AML without MRC, patients with AML-MRC-M/AML-MRC-H had similar outcomes to those with intermediate risk AML by European LeukemiaNet criteria. Intensive therapy was associated with improved OS in patients with AML-MRC-M (HR 0.42, CI 0.19-0.94, P = .036) and with improved EFS in AML-MRC-M and AML-MRC-H (HR 0.26, CI 0.10-0.63, P = .003). This data suggests that not all diagnostic criteria for AML-MRC define high-risk patients and that specific subgroups may benefit from different therapeutic interventions.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Leucemia Mieloide Aguda , Mutação , Síndromes Mielodisplásicas , Proteínas de Neoplasias/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Compostos Bicíclicos Heterocíclicos com Pontes/administração & dosagem , Citarabina/administração & dosagem , Daunorrubicina/administração & dosagem , Intervalo Livre de Doença , Feminino , Humanos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidade , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/diagnóstico , Síndromes Mielodisplásicas/tratamento farmacológico , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/mortalidade , Sulfonamidas/administração & dosagem , Taxa de Sobrevida
5.
Cancer Causes Control ; 30(4): 409-415, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30868330

RESUMO

PURPOSE: Identifying demographic, clinical, and geographical factors that contribute to disparities in the receipt of physician recommended chemotherapy in breast cancer patients. METHODS: The Texas Cancer Registry was used to identify women aged ≥ 18 years with invasive breast cancer diagnosed from 2007 to 2011 who received a recommendation for chemotherapy. Multivariable logistic regression was performed to determine associations between demographic and clinical factors and the receipt of chemotherapy. Cox proportional regression was used to estimate the hazard ratio (HR) for overall survival. Spatial analysis was conducted using Poisson models for breast cancer mortality and receipt of chemotherapy. RESULTS: Age ≥ 65 years, residence in areas with > 20% poverty index, and early disease stage were associated with lack of receipt of chemotherapy (all p < 0.001). Lack of receipt of chemotherapy was associated with decreased overall survival (HR 1.33, 95% CI 1.12-1.59, p = 0.001). A 38-county cluster in West Texas had lower receipt of chemotherapy (relative risk 0.88, p = 0.02) and increased breast cancer mortality (p = 0.03) compared to the rest of Texas. CONCLUSION: Older age, increased poverty and rural geographical location are barriers to the receipt of chemotherapy. Interventions that target these barriers may reduce health disparities and improve breast cancer survival.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Médicos , Adolescente , Adulto , Idoso , Neoplasias da Mama/diagnóstico , Feminino , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Sistema de Registros , Texas , Adulto Jovem
6.
Bioinformatics ; 34(7): 1243-1245, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29194470

RESUMO

Motivation: Differential network analysis is an important way to understand network rewiring involved in disease progression and development. Building differential networks from multiple 'omics data provides insight into the holistic differences of the interactive system under different patient-specific groups. DINGO was developed to infer group-specific dependencies and build differential networks. However, DINGO and other existing tools are limited to analyze data arising from a single platform, and modeling each of the multiple 'omics data independently does not account for the hierarchical structure of the data. Results: We developed the iDINGO R package to estimate group-specific dependencies and make inferences on the integrative differential networks, considering the biological hierarchy among the platforms. A Shiny application has also been developed to facilitate easier analysis and visualization of results, including integrative differential networks and hub gene identification across platforms. Availability and implementation: R package is available on CRAN (https://cran.r-project.org/web/packages/iDINGO) and Shiny application at https://github.com/MinJinHa/iDINGO. Contact: mjha@mdanderson.org. Supplementary information: Supplementary data are available at Bioinformatics online.


Assuntos
Biologia Computacional/métodos , Progressão da Doença , Software , Redes Reguladoras de Genes , Humanos , Redes e Vias Metabólicas
7.
Phys Chem Chem Phys ; 21(20): 10311-10324, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31070634

RESUMO

A detailed reaction network is proposed for the pyrolysis and desulfurization of hexyl sulfide in the presence or absence of both supercritical water (SCW) and hexadecane, but without any added H2 or catalyst, for T = 400-450 °C. The new kinetic model is developed using the Reaction Mechanism Generator (RMG) software where most of the rate coefficients are derived from quantum chemical calculations. We previously reported that pentane, carbon monoxide and carbon dioxide are major products of hexyl sulfide desulfurization in SCW, but not in the anhydrous pyrolysis of hexyl sulfide. The observation of CO and CO2 in the reaction products indicates that water effectively acts as a hydrogen source; presumably this assists in sulfur reduction to H2S. Kinetic parameters for several of the important reactions are calculated using transition state theory and quantum chemical calculations at the CBS-QB3 level of theory and then further refined using CCSD(T)-F12//cc-pVTZ-F12 single point energies. Predictions from the new kinetic model agree with factor-of-2 accuracy with new and previously published experimental data for hexyl sulfide conversion and for yields of most major products, either neat or in a hexadecane solvent, both in the presence and absence of SCW. Flux analysis was then used to identify the most important reaction steps, and sensitivity analysis was used to propose reactions that should be studied further in the future to decrease the model's uncertainty. This study establishes the molecular role of water as diluent, hydrogen bond donor, and reductant in the decomposition of hexyl sulfide. Future work to add molecular weight growth pathways to the model would lead to a more complete mechanism, resulting in improved predictions of product yields.

8.
Phys Chem Chem Phys ; 18(31): 21651-8, 2016 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-27431650

RESUMO

The automated Reaction Mechanism Generator (RMG), using rate parameters derived from ab initio CCSD(T) calculations, is used to build reaction networks for the thermal decomposition of di-tert-butyl sulfide. Simulation results were compared with data from pyrolysis experiments with and without the addition of a cyclohexene inhibitor. Purely free-radical chemistry did not properly explain the reactivity of di-tert-butyl sulfide, as the previous experimental work showed that the sulfide decomposed via first-order kinetics in the presence and absence of the radical inhibitor. The concerted unimolecular decomposition of di-tert-butyl sulfide to form isobutene and tert-butyl thiol was found to be a key reaction in both cases, as it explained the first-order sulfide decomposition. The computer-generated kinetic model predictions quantitatively match most of the experimental data, but the model is apparently missing pathways for radical-induced decomposition of thiols to form elemental sulfur. Cyclohexene has a significant effect on the composition of the radical pool, and this led to dramatic changes in the resulting product distribution.

9.
Phys Chem Chem Phys ; 17(20): 13625-39, 2015 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-25941683

RESUMO

Potential energy surfaces and reaction kinetics were calculated for 40 reactions involving sulfur and oxygen. This includes 11 H2O addition, 8 H2S addition, 11 hydrogen abstraction, 7 beta scission, and 3 elementary tautomerization reactions, which are potentially relevant in the combustion and desulfurization of sulfur compounds found in various fuel sources. Geometry optimizations and frequencies were calculated for reactants and transition states using B3LYP/CBSB7, and potential energies were calculated using CBS-QB3 and CCSD(T)-F12a/VTZ-F12. Rate coefficients were calculated using conventional transition state theory, with corrections for internal rotations and tunneling. Additionally, thermochemical parameters were calculated for each of the compounds involved in these reactions. With few exceptions, rate parameters calculated using the two potential energy methods agreed reasonably, with calculated activation energies differing by less than 5 kJ mol(-1). The computed rate coefficients and thermochemical parameters are expected to be useful for kinetic modeling.

10.
Phys Chem Chem Phys ; 16(20): 9220-8, 2014 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-24728624

RESUMO

The cleavage of C-S linkages plays a key role in fuel processing and organic geochemistry. Water is known to affect these processes, and several hypotheses have been proposed, but the mechanism has been elusive. Here we use both experiment and theory to demonstrate that supercritical water reacts with intermediates formed during alkyl sulfide decomposition. During hexyl sulfide decomposition in supercritical water, pentane and CO + CO2 were detected in addition to the expected six carbon products. A multi-step reaction sequence for hexyl sulfide reacting with supercritical water is proposed which explains the surprising products, and quantum chemical calculations provide quantitative rates that support the proposed mechanism. The key sequence is cleavage of one C-S bond to form a thioaldehyde via radical reactions, followed by a pericyclic addition of water to the C[double bond, length as m-dash]S bond to form a geminal mercaptoalcohol. The mercaptoalcohol decomposes into an aldehyde and H2S either directly or via a water-catalyzed 6-membered ring transition state. The aldehyde quickly decomposes into CO plus pentane by radical reactions. The time is ripe for quantitative modelling of organosulfur reaction kinetics based on modern quantum chemistry.


Assuntos
Teoria Quântica , Sulfetos/química , Água/química , Cinética
11.
Nat Commun ; 15(1): 1203, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38331987

RESUMO

DNA damage resistance is a major barrier to effective DNA-damaging therapy in multiple myeloma (MM). To discover mechanisms through which MM cells overcome DNA damage, we investigate how MM cells become resistant to antisense oligonucleotide (ASO) therapy targeting Interleukin enhancer binding factor 2 (ILF2), a DNA damage regulator that is overexpressed in 70% of MM patients whose disease has progressed after standard therapies have failed. Here, we show that MM cells undergo adaptive metabolic rewiring to restore energy balance and promote survival in response to DNA damage activation. Using a CRISPR/Cas9 screening strategy, we identify the mitochondrial DNA repair protein DNA2, whose loss of function suppresses MM cells' ability to overcome ILF2 ASO-induced DNA damage, as being essential to counteracting oxidative DNA damage. Our study reveals a mechanism of vulnerability of MM cells that have an increased demand for mitochondrial metabolism upon DNA damage activation.


Assuntos
Mieloma Múltiplo , Humanos , Mieloma Múltiplo/genética , DNA Helicases/metabolismo , Reprogramação Metabólica , Reparo do DNA , Dano ao DNA
12.
bioRxiv ; 2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36865225

RESUMO

DNA damage resistance is a major barrier to effective DNA-damaging therapy in multiple myeloma (MM). To discover novel mechanisms through which MM cells overcome DNA damage, we investigated how MM cells become resistant to antisense oligonucleotide (ASO) therapy targeting ILF2, a DNA damage regulator that is overexpressed in 70% of MM patients whose disease has progressed after standard therapies have failed. Here, we show that MM cells undergo an adaptive metabolic rewiring and rely on oxidative phosphorylation to restore energy balance and promote survival in response to DNA damage activation. Using a CRISPR/Cas9 screening strategy, we identified the mitochondrial DNA repair protein DNA2, whose loss of function suppresses MM cells' ability to overcome ILF2 ASO-induced DNA damage, as being essential to counteracting oxidative DNA damage and maintaining mitochondrial respiration. Our study revealed a novel vulnerability of MM cells that have an increased demand for mitochondrial metabolism upon DNA damage activation. STATEMENT OF SIGNIFICANCE: Metabolic reprogramming is a mechanism through which cancer cells maintain survival and become resistant to DNA-damaging therapy. Here, we show that targeting DNA2 is synthetically lethal in myeloma cells that undergo metabolic adaptation and rely on oxidative phosphorylation to maintain survival after DNA damage activation.

13.
Clin Epigenetics ; 14(1): 81, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35765052

RESUMO

Epigenetic abnormalities in DNA hydroxymethylation (5hmC) have been detected in patients with myeloid neoplasms, suggesting that 5hmC might act as a valuable epigenetic mark to reflect the disease status of myeloid neoplasms. Here, we report systematic genome-wide mapping of the DNA hydroxymethylomes in over 70 patients with myeloid neoplasms. Our integrative analysis leads to the identification of distinct 5hmC signatures that can sensitively discriminate patients from healthy individuals. At the molecular level, we unveiled dynamic 5hmC changes within key transcription factor (e.g., the CEBP family) binding motifs that are essential for hematopoiesis and myeloid lineage specification. 5hmC redistribution was found to alter the genome-wide binding of CEBP-α, thereby reprogramming transcriptional outputs to affect leukemia cell survival and stemness. Taken together, we provide a comprehensive 5hmC atlas representative of myeloid neoplasms, which sets the stage for future exploration on the epigenetic etiology of hematological malignancies. Mechanistically, our study further furnishes important insights into how abnormal 5hmC distribution in patients directly interrupts the binding of transcription factors to reshape transcriptional landscapes and aggravate leukemogenesis.


Assuntos
Neoplasias Hematológicas , Leucemia , Carcinogênese , Sobrevivência Celular , Metilação de DNA , Neoplasias Hematológicas/genética , Humanos , Leucemia/genética
14.
Leukemia ; 36(8): 2097-2107, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35697791

RESUMO

Loss-of-function TET2 mutations are recurrent somatic lesions in chronic myelomonocytic leukemia (CMML). KDM6B encodes a histone demethylase involved in innate immune regulation that is overexpressed in CMML. We conducted genomic and transcriptomic analyses in treatment naïve CMML patients and observed that the patients carrying both TET2 mutations and KDM6B overexpression constituted 18% of the cohort and 42% of patients with TET2 mutations. We therefore hypothesized that KDM6B overexpression cooperated with TET2 deficiency in CMML pathogenesis. We developed a double-lesion mouse model with both aberrations, and discovered that the mice exhibited a more prominent CMML-like phenotype than mice with either Tet2 deficiency or KDM6B overexpression alone. The phenotype includes monocytosis, anemia, splenomegaly, and increased frequencies and repopulating activity of bone marrow (BM) hematopoietic stem and progenitor cells (HSPCs). Significant transcriptional alterations were identified in double-lesion mice, which were associated with activation of proinflammatory signals and repression of signals maintaining genome stability. Finally, KDM6B inhibitor reduced BM repopulating activity of double-lesion mice and tumor burden in mice transplanted with BM-HSPCs from CMML patients with TET2 mutations. These data indicate that TET2 deficiency and KDM6B overexpression cooperate in CMML pathogenesis of and that KDM6B could serve as a potential therapeutic target in this disease.


Assuntos
Proteínas de Ligação a DNA , Dioxigenases , Histona Desmetilases com o Domínio Jumonji , Leucemia Mielomonocítica Crônica , Leucemia Mielomonocítica Juvenil , Animais , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Dioxigenases/deficiência , Dioxigenases/genética , Dioxigenases/metabolismo , Perfilação da Expressão Gênica , Genoma , Humanos , Histona Desmetilases com o Domínio Jumonji/biossíntese , Histona Desmetilases com o Domínio Jumonji/genética , Leucemia Mielomonocítica Crônica/genética , Leucemia Mielomonocítica Crônica/metabolismo , Leucemia Mielomonocítica Juvenil/genética , Leucemia Mielomonocítica Juvenil/metabolismo , Mutação com Perda de Função , Camundongos , Mutação , Proteínas Proto-Oncogênicas/genética
15.
Exp Hematol ; 115: 44-53, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36150563

RESUMO

Hypomethylating agents (HMAs) are the standard of care for myelodysplastic syndromes (MDS) and chronic myelomonocytic leukemia (CMML). HMA treatment failure is a major clinical problem and its mechanisms are poorly characterized. We performed RNA sequencing in CD34+ bone marrow stem hematopoietic stem and progenitor cells (BM-HSPCs) from 51 patients with CMML and MDS before HMA treatment and compared transcriptomic signatures between responders and nonresponders. We observed very few genes with significant differential expression in HMA non-responders versus responders, and the commonly altered genes in non-responders to both azacitidine (AZA) and decitabine (DAC) treatments were immunoglobulin genes. Gene set analysis identified 78 biological pathways commonly altered in non-responders to both treatments. Among these, we determined that the γ-aminobutyric acid (GABA) receptor signaling significantly affected hematopoiesis in both human BM-HSPCs and mice, indicating that the transcriptomic signatures identified here could serve as candidate biomarkers and therapeutic targets for HMA failure in MDS and CMML.


Assuntos
Leucemia Mielomonocítica Crônica , Leucemia Mielomonocítica Juvenil , Síndromes Mielodisplásicas , Humanos , Camundongos , Animais , Leucemia Mielomonocítica Crônica/tratamento farmacológico , Leucemia Mielomonocítica Crônica/genética , Transcriptoma , Síndromes Mielodisplásicas/tratamento farmacológico , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/metabolismo , Azacitidina/farmacologia , Azacitidina/uso terapêutico , Leucemia Mielomonocítica Juvenil/tratamento farmacológico
16.
NEJM Evid ; 1(10): EVIDoa2200034, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38319837

RESUMO

BACKGROUND: The hypomethylating agents are part of the standard of care in the treatment of myelodysplastic syndromes (MDS), but their role in patients with lower-risk disease is unclear. METHODS: We randomly assigned patients with previously untreated MDS with low/intermediate-1 risk by the International Prognostic Scoring System with a Bayesian response-adaptive design to receive either 20 mg/m2 decitabine daily or 75 mg/m2 azacitidine daily on days 1 to 3 every 28-day cycle. RESULTS: A total of 113 patients were treated: 73 (65%) with decitabine and 40 (35%) with azacitidine. The overall response rate was 67% and 48% in the decitabine and azacitidine groups, respectively (P=0.042); among 59 patients with baseline transfusion dependency, 19 (32%) reached transfusion independence (decitabine, 16 of 39 [41%]; azacitidine, 3 of 20 [15%]; P=0.039). Of the 19 patients who reached transfusion independence, the median duration of transfusion independency was 22 months. Among 54 patients who were transfusion independent at baseline, 5 patients (9%) became transfusion dependent after therapy. No early death was observed. With a median follow-up of 68 months, the median overall event-free survival and overall survival were 17 months and 33 months, respectively. CONCLUSIONS: Attenuated dose treatment of hypomethylating agents in patients with lower-risk MDS can improve outcomes without dose-limiting side effects in a high-risk cohort as defined by the Lower-Risk Prognostic Scoring System. (Funded in part by The University of Texas MD Anderson Cancer Center and others; ClinicalTrials.gov number, NCT01720225.)


Assuntos
Azacitidina , Síndromes Mielodisplásicas , Adulto , Humanos , Decitabina , Resultado do Tratamento
17.
Nat Med ; 28(3): 557-567, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35241842

RESUMO

Myelodysplastic syndromes (MDS) are heterogeneous neoplastic disorders of hematopoietic stem cells (HSCs). The current standard of care for patients with MDS is hypomethylating agent (HMA)-based therapy; however, almost 50% of MDS patients fail HMA therapy and progress to acute myeloid leukemia, facing a dismal prognosis due to lack of approved second-line treatment options. As cancer stem cells are the seeds of disease progression, we investigated the biological properties of the MDS HSCs that drive disease evolution, seeking to uncover vulnerabilities that could be therapeutically exploited. Through integrative molecular profiling of HSCs and progenitor cells in large patient cohorts, we found that MDS HSCs in two distinct differentiation states are maintained throughout the clinical course of the disease, and expand at progression, depending on recurrent activation of the anti-apoptotic regulator BCL-2 or nuclear factor-kappa B-mediated survival pathways. Pharmacologically inhibiting these pathways depleted MDS HSCs and reduced tumor burden in experimental systems. Further, patients with MDS who progressed after failure to frontline HMA therapy and whose HSCs upregulated BCL-2 achieved improved clinical responses to venetoclax-based therapy in the clinical setting. Overall, our study uncovers that HSC architectures in MDS are potential predictive biomarkers to guide second-line treatments after HMA failure. These findings warrant further investigation of HSC-specific survival pathways to identify new therapeutic targets of clinical potential in MDS.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes , Síndromes Mielodisplásicas , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Células-Tronco Hematopoéticas/patologia , Humanos , Síndromes Mielodisplásicas/tratamento farmacológico , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/patologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Sulfonamidas
18.
iScience ; 24(9): 103017, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34522860

RESUMO

The mechanisms by which transcriptional activation domains (tADs) initiate eukaryotic gene expression have been an enigma for decades because most tADs lack specificity in sequence, structure, and interactions with targets. Machine learning analysis of data sets of tAD sequences generated in vivo elucidated several functionality rules: the functional tAD sequences should (i) be devoid of or depleted with basic amino acid residues, (ii) be enriched with aromatic and acidic residues, (iii) be with aromatic residues localized mostly near the terminus of the sequence, and acidic residues localized more internally within a span of 20-30 amino acids, (iv) be with both aromatic and acidic residues preferably spread out in the sequence and not clustered, and (v) not be separated by occasional basic residues. These and other more subtle rules are not absolute, reflecting absence of a tAD consensus sequence, enormous variability, and consistent with surfactant-like tAD biochemical properties. The findings are compatible with the paradigm-shifting nucleosome detergent mechanism of gene expression activation, contributing to the development of the liquid-liquid phase separation model and the biochemistry of near-stochastic functional allosteric interactions.

19.
Nat Commun ; 12(1): 2606, 2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33972557

RESUMO

Understanding resistance mechanisms to targeted therapies and immune checkpoint blockade in mutant KRAS lung cancers is critical to developing novel combination therapies and improving patient survival. Here, we show that MEK inhibition enhanced PD-L1 expression while PD-L1 blockade upregulated MAPK signaling in mutant KRAS lung tumors. Combined MEK inhibition with anti-PD-L1 synergistically reduced lung tumor growth and metastasis, but tumors eventually developed resistance to sustained combinatorial therapy. Multi-platform profiling revealed that resistant lung tumors have increased infiltration of Th17 cells, which secrete IL-17 and IL-22 cytokines to promote lung cancer cell invasiveness and MEK inhibitor resistance. Antibody depletion of IL-17A in combination with MEK inhibition and PD-L1 blockade markedly reduced therapy-resistance in vivo. Clinically, increased expression of Th17-associated genes in patients treated with PD-1 blockade predicted poorer overall survival and response in melanoma and predicated poorer response to anti-PD1 in NSCLC patients. Here we show a triple combinatorial therapeutic strategy to overcome resistance to combined MEK inhibitor and PD-L1 blockade.


Assuntos
Antineoplásicos Imunológicos/farmacologia , Antígeno B7-H1/metabolismo , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Proto-Oncogênicas p21(ras)/genética , Células Th17/metabolismo , Proteína Supressora de Tumor p53/genética , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antígeno B7-H1/imunologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/imunologia , Sinergismo Farmacológico , Feminino , Humanos , Inibidores de Checkpoint Imunológico/imunologia , Imuno-Histoquímica , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/genética , Masculino , Camundongos , Camundongos Knockout , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Invasividade Neoplásica/genética , Invasividade Neoplásica/imunologia , Metástase Neoplásica , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Células Th17/imunologia , Proteína Supressora de Tumor p53/metabolismo
20.
Leuk Res ; 101: 106511, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33517186

RESUMO

Chronic myelomonocytic leukemia (CMML) is characterized by myelomonocytic bias and monocytic proliferation. Whether cell-intrinsic innate immune or inflammatory upregulation mediate disease pathogenesis and phenotype or whether the degree of aberrant monocytic differentiation influences outcomes remains unclear. We compared the transcriptomic features of bone marrow CD34+ cells from 19 patients with CMML and compared to healthy individuals. A total of 1495 genes had significantly differential expression in CMML (q<0.05, fold change>2), including 1271 genes that were significantly upregulated and 224 that were significantly downregulated in CMML. Top upregulated genes were associated with interferon (IFN) alpha and beta signaling, chemokine receptors, IFN gamma, G protein-coupled receptor ligand signaling, and genes involved in immunomodulatory interactions between lymphoid and non-lymphoid cells. Additionally, 6 gene sets were differentially upregulated and 139 were significantly downregulated in patients with myeloproliferative compared to myelodysplastic CMML. A total of 23 genes involved in regulation of monopoiesis were upregulated in CMML compared to healthy controls. We developed a prediction model using Cox regression including 3 of these genes, which differentiated patients into two prognostic subsets with distinct survival outcomes. This data warrants further evaluation of the roles and therapeutic potential of type I IFN signaling and monopoiesis in CMML.


Assuntos
Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Interferon Tipo I/administração & dosagem , Leucemia Mielomonocítica Crônica , Mielopoese/efeitos dos fármacos , Proteínas de Neoplasias , Regulação para Cima/efeitos dos fármacos , Feminino , Humanos , Leucemia Mielomonocítica Crônica/tratamento farmacológico , Leucemia Mielomonocítica Crônica/genética , Leucemia Mielomonocítica Crônica/metabolismo , Leucemia Mielomonocítica Crônica/patologia , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética
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