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BACKGROUND AND PURPOSE: Colorectal cancer (CRC) ranks second in mortality worldwide and requires effective and affordable remedies. Cyclovirobuxine D (CVB-D) is the main effective component of Huangyangning tablet, an approved traditional patent medicine, which is mainly used for cardiovascular treatment. As a multibioactive natural compound, CVB-D possesses underlying anticancer activities. EXPERIMENTAL APPROACH: Cell viability and clone-forming ability were determined in human CRC lines. Western blot, immunofluorescence assay, transmission electron microscopy and senescence-associated ß-galactosidase (SA-ß-Gal) staining were utilized to investigate cell autophagy and senescence. The molecular mechanisms were explored by virtual prediction and experimental validation. Patient-derived xenograft (PDX), dextran sulfate sodium salt (DSS), and azomethane (AOM)/DSS mouse models were employed for in vivo studies. KEY RESULTS: CVB-D inhibited the growth and development of advanced CRC cells / mice by inducing autophagic and senescent activities through the chaperonin containing TCP1 subunit 3 (CCT3)/yes-associated protein (YAP) axis. CVB-D acted as a promising inhibitor of CCT3 by interacting with its ATP site. In PDX tumours, CVB-D showed potential therapeutic effects by targeting CCT3. Treatment with CVB-D alleviated the mouse model of colitis induced by DSS and attenuated AOM/DSS-induced formation of adenomatous polyps by its action on CCT3. CONCLUSIONS AND IMPLICATIONS: Our study has provided a scientific basis for the suggestion that CVB-D may be recognized as a prospective drug candidate for the therapy of CRC in patients.
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Precise gene expression, crucial for normal development and health, depends on the co-ordinated assembly and function of various factors within the crowded nucleus. Recent evidence suggests that this process is in part regulated by mesoscale compartmentalization and concentration of transcriptional components within condensates, offering a new perspective on gene regulation. Dysregulation of transcriptional condensates is increasingly associated with diseases, indicating a potential role in pathogenesis. In this mini-review, we provide a concise overview of the current understanding of the formation and function of transcriptional condensates, with a specific focus on recent advances in their dysregulation and implications in diseases, notably cancer. We also address limitations in the field and highlight open questions for future research.
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Regulação da Expressão Gênica , Neoplasias , Transcrição Gênica , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Regulação da Expressão Gênica/genética , Núcleo Celular/genética , Núcleo Celular/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
Refractory heart failure (RHF), or end-stage heart failure, has a poor prognosis and high case fatality rate, making it one of the therapeutic difficulties in the cardiovascular field. Despite the continuous abundance of methods and means for treating RHF in modern medicine, it still cannot meet the clinical needs of patients with RHF. How to further reduce the mortality rate and readmission rate of patients with RHF and improve their quality of life is still a difficult point in current research. In China, traditional Chinese medicine (TCM) has been widely used and has accumulated rich experience in the treatment of RHF due to its unique efficacy and safety advantages. Based on this, we comprehensively summarized and analyzed the clinical evidence and mechanism of action of TCM in the treatment of RHF and proposed urgent scientific issues and future research strategies for the treatment of RHF with TCM, to provide reference for the treatment of RHF.
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High-performance photodetectors with the detection capability of linearly polarized light have broad applications in both military and civilian fields. Quasi-one-dimensional ZrS3 as an emerging anisotropic two-dimensional material has come under the spotlight owing to its intriguing properties. However, the performance of the ZrS3 photodetector is seriously restricted by its low responsivity. Herein, a novel high-performance photodetector based on the van der Waals ZrS3/MoS2 heterostructure is proposed. Attributed to the charge trapping-assisted photogating effect, interlayer carrier transitions, and fast spatial separation of the photogenerated electron-hole pairs, the device displays superior photoresponse characteristics ranging from the ultraviolet to the visible spectrum in terms of high responsivity up to 212 A/W, an extraordinary external quantum efficiency of 8.5 × 104%, and a prompt rise/decay time of 0.19/0.38 ms. In addition, owing to the profound birefringence and dichroism effects in ZrS3 together with strong light-matter interactions in the heterostructure, profound linear-polarization sensitivity is demonstrated with a dichroic ratio of about 2.8. Overall, this photodetector not only is integrated with the excellent properties of ZrS3 and monolayer MoS2 but also further enhances the advantages through interlayer couplings, which demonstrate the strong potential of the ZrS3-based devices for high-performance, ultrafast, and polarization-sensitive photodetection.
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Eleven-nineteen leukemia (ENL) is an epigenetic reader protein that drives oncogenic transcriptional programs in acute myeloid leukemia (AML). AML is one of the deadliest hematopoietic malignancies, with an overall 5-year survival rate of 27%. The epigenetic reader activity of ENL is mediated by its YEATS domain that binds to acetyl and crotonyl marks on histone tails and colocalizes with promoters of actively transcribed genes that are essential for leukemia. Prior to the discovery of TDI-11055, existing inhibitors of ENL YEATS showed in vitro potency, but had not shown efficacy in in vivo animal models. During the course of the medicinal chemistry campaign described here, we identified ENL YEATS inhibitor TDI-11055 that has an improved pharmacokinetic profile and is appropriate for in vivo evaluation of the ENL YEATS inhibition mechanism in AML.
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Cobalt-nitrogen co-doped carbon nanotubes (Co3@NCNT-800) were synthesized via a facile and economical approach to investigate the efficient degradation of organic pollutants in aqueous environments. This material demonstrated high catalytic efficiency in the degradation of carbamazepine (CBZ) in the presence of peroxymonosulfate (PMS). The experimental data revealed that at a neutral pH of 7 and an initial CBZ concentration of 20 mg/L, the application of Co3@NCNT-800 at 0.2 g/L facilitated a degradation rate of 64.7% within 60 min. Mechanistic investigations indicated that the presence of pyridinic nitrogen and cobalt species enhanced the generation of reactive oxygen species. Radical scavenging assays and electron spin resonance spectroscopy confirmed that radical and nonradical pathways contributed to CBZ degradation, with the nonradical mechanism being predominant. This research presents the development of a novel PMS catalyst, synthesized through an efficient and stable method, which provides a cost-effective solution for the remediation of organic contaminants in water.
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Nanotubos de Carbono , Peróxidos , Benzodiazepinas , Carbamazepina , Cobalto , Nitrogênio , ÁguaRESUMO
Gain-of-function mutations in the histone acetylation "reader" eleven-nineteen-leukemia (ENL), found in acute myeloid leukemia (AML) and Wilms tumor, are known to drive condensate formation and gene activation in cellular systems. However, their role in tumorigenesis remains unclear. Using a conditional knock-in mouse model, we show that mutant ENL perturbs normal hematopoiesis, induces aberrant expansion of myeloid progenitors, and triggers rapid onset of aggressive AML. Mutant ENL alters developmental and inflammatory gene programs in part by remodeling histone modifications. Mutant ENL forms condensates in hematopoietic stem/progenitor cells at key leukemogenic genes, and disrupting condensate formation via mutagenesis impairs its chromatin and oncogenic function. Moreover, treatment with an acetyl-binding inhibitor of the mutant ENL displaces these condensates from target loci, inhibits mutant ENL-induced chromatin changes, and delays AML initiation and progression in vivo. Our study elucidates the function of ENL mutations in chromatin regulation and tumorigenesis and demonstrates the potential of targeting pathogenic condensates in cancer treatment. Significance: A direct link between ENL mutations, condensate formation, and tumorigenesis is lacking. This study elucidates the function and mechanism of ENL mutations in leukemogenesis, establishing these mutations as bona fide oncogenic drivers. Our results also support the role of condensate dysregulation in cancer and reveal strategies to target pathogenic condensates.
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Mutação , Animais , Camundongos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/metabolismo , Carcinogênese/genética , Humanos , Código das Histonas , Histonas/metabolismoRESUMO
Objective.Accurate assessment of pleural line is crucial for the application of lung ultrasound (LUS) in monitoring lung diseases, thereby aim of this study is to develop a quantitative and qualitative analysis method for pleural line.Approach.The novel cascaded deep learning model based on convolution and multilayer perceptron was proposed to locate and segment the pleural line in LUS images, whose results were applied for quantitative analysis of textural and morphological features, respectively. By using gray-level co-occurrence matrix and self-designed statistical methods, eight textural and three morphological features were generated to characterize the pleural lines. Furthermore, the machine learning-based classifiers were employed to qualitatively evaluate the lesion degree of pleural line in LUS images.Main results.We prospectively evaluated 3770 LUS images acquired from 31 pneumonia patients. Experimental results demonstrated that the proposed pleural line extraction and evaluation methods all have good performance, with dice and accuracy of 0.87 and 94.47%, respectively, and the comparison with previous methods found statistical significance (P< 0.001 for all). Meanwhile, the generalization verification proved the feasibility of the proposed method in multiple data scenarios.Significance.The proposed method has great application potential for assessment of pleural line in LUS images and aiding lung disease diagnosis and treatment.
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Pulmão , Pneumonia , Humanos , Pulmão/diagnóstico por imagem , Tórax , Ultrassonografia/métodos , Redes Neurais de ComputaçãoRESUMO
Controlling the collective behavior of micro/nanomotors with ultrasound may enable new functionality in robotics, medicine, and other engineering disciplines. Currently, various collective behaviors of nanomotors, such as assembly, reconfiguration, and disassembly, have been explored by using acoustic fields with a fixed frequency, while regulating their collective behaviors by varying the ultrasound frequency still remains challenging. In this work, we designed an ultrasound manipulation methodology that allows nanomotors to exhibit different collective behaviors by regulating the applied ultrasound frequency. The experimental results and FEM simulations demonstrate that the secondary ultrasonic waves produced from the edge of the sample cell lead to the formation of complex acoustic pressure fields and microfluidic patterns, which causes these collective behaviors. This work has important implications for the design of artificial actuated nanomotors and optimize their performances.
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Thoracic echocardiography (TTE) can provide sufficient cardiac structure information, evaluate hemodynamics and cardiac function, and is an effective method for atrial septal defect (ASD) examination. This paper aims to study a deep learning method based on cardiac ultrasound video to assist in ASD diagnosis. We chose four standard views in pediatric cardiac ultrasound to identify atrial septal defects; the four standard views were as follows: subcostal sagittal view of the atrium septum (subSAS), apical four-chamber view (A4C), the low parasternal four-chamber view (LPS4C), and parasternal short-axis view of large artery (PSAX). We enlist data from 300 children patients as part of a double-blind experiment for five-fold cross-validation to verify the performance of our model. In addition, data from 30 children patients (15 positives and 15 negatives) are collected for clinician testing and compared to our model test results (these 30 samples do not participate in model training). In our model, we present a block random selection, maximal agreement decision, and frame sampling strategy for training and testing respectively, resNet18 and r3D networks are used to extract the frame features and aggregate them to build a rich video-level representation. We validate our model using our private dataset by five cross-validation. For ASD detection, we achieve 89.33 ± 3.13 AUC, 84.95 ± 3.88 accuracy, 85.70 ± 4.91 sensitivity, 81.51 ± 8.15 specificity, and 81.99 ± 5.30 F1 score. The proposed model is a multiple instances learning-based deep learning model for video atrial septal defect detection which effectively improves ASD detection accuracy when compared to the performances of previous networks and clinical doctors.
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Aprendizado Profundo , Ecocardiografia , Comunicação Interatrial , Humanos , Comunicação Interatrial/diagnóstico por imagem , Criança , Ecocardiografia/métodos , Feminino , Masculino , Pré-Escolar , Método Duplo-Cego , Lactente , Interpretação de Imagem Assistida por Computador/métodos , Gravação em Vídeo , AdolescenteRESUMO
Background: The causal link between Type 2 diabetes (T2D) and coronary atherosclerosis has been established through wet lab experiments; however, its analysis with Genome-wide association studies (GWAS) data remains unexplored. This study aims to validate this relationship using Mendelian randomization analysis and explore the potential mediation of VLDL in this mechanism. Methods: Employing Mendelian randomization analysis, we investigated the causal connection between T2D and coronary atherosclerosis. We utilized GWAS summary statistics from European ancestry cohorts, comprising 23,363 coronary atherosclerosis patients and 195,429 controls, along with 32,469 T2D patients and 183,185 controls. VLDL levels, linked to SNPs, were considered as a potential mediating causal factor that might contribute to coronary atherosclerosis in the presence of T2D. We employed the inverse variance weighted (IVW), Egger regression (MR-Egger), weighted median, and weighted model methods for causal effect estimation. A leave-one-out sensitivity analysis was conducted to ensure robustness. Results: Our Mendelian randomization analysis demonstrated a genetic association between T2D and an increased coronary atherosclerosis risk, with the IVW estimate at 1.13 [95% confidence interval (CI): 1.07-1.20]. Additionally, we observed a suggestive causal link between T2D and VLDL levels, as evidenced by the IVW estimate of 1.02 (95% CI: 0.98-1.07). Further supporting lipid involvement in coronary atherosclerosis pathogenesis, the IVW-Egger estimate was 1.30 (95% CI: 1.06-1.58). Conclusion: In conclusion, this study highlights the autonomous contributions of T2D and VLDL levels to coronary atherosclerosis development. T2D is linked to a 13.35% elevated risk of coronary atherosclerosis, and within T2D patients, VLDL concentration rises by 2.49%. Notably, each standard deviation increase in VLDL raises the likelihood of heart disease by 29.6%. This underscores the significant role of lipid regulation, particularly VLDL, as a mediating pathway in coronary atherosclerosis progression.
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Dermal fibroblasts (dFBs) defend against deep bacterial skin infections by differentiating into preadipocytes (pAds) that produce the antimicrobial peptide cathelicidin; this differentiation is known as the dermal reactive adipogenesis response. However, the role of dFBs in fungal infection remains unknown. Here, we found that cathelicidin-producing pAds were present in high numbers in skin lesions from patients with cutaneous Candida granulomas. Second, we showed that dermal Candida albicans (C. albicans) infection in mice robustly triggered the dermal reactive adipogenesis response and induced cathelicidin expression, and inhibition of adipogenesis with pharmacological inhibitors of peroxisome proliferator-activated receptor γ (PPARγ) impaired skin resistance to C. albicans. In vitro, C. albicans products induced cathelicidin expression in pAds, and differentiating pAds markedly suppressed the growth of C. albicans by producing cathelicidin. Finally, we showed that C. albicans induced an antimicrobial response in pAds through the FGFR-MEK-ERK pathway. Together, our data reveal a previously unknown role of dFBs in the defense against skin infection caused by C. albicans.
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Candida albicans , Candidíase , Humanos , Camundongos , Animais , Candida albicans/metabolismo , Catelicidinas , Sistema de Sinalização das MAP Quinases , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos AntimicrobianosRESUMO
Semantic segmentation for extracting buildings and roads from uncrewed aerial vehicle (UAV) remote sensing images by deep learning becomes a more efficient and convenient method than traditional manual segmentation in surveying and mapping fields. In order to make the model lightweight and improve the model accuracy, a lightweight network using object attention (LOANet) for buildings and roads from UAV aerial remote sensing images is proposed. The proposed network adopts an encoder-decoder architecture in which a lightweight densely connected network (LDCNet) is developed as the encoder. In the decoder part, the dual multi-scale context modules which consist of the atrous spatial pyramid pooling module (ASPP) and the object attention module (OAM) are designed to capture more context information from feature maps of UAV remote sensing images. Between ASPP and OAM, a feature pyramid network (FPN) module is used to fuse multi-scale features extracted from ASPP. A private dataset of remote sensing images taken by UAV which contains 2431 training sets, 945 validation sets, and 475 test sets is constructed. The proposed basic model performs well on this dataset, with only 1.4M parameters and 5.48G floating point operations (FLOPs), achieving excellent mean Intersection-over-Union (mIoU). Further experiments on the publicly available LoveDA and CITY-OSM datasets have been conducted to further validate the effectiveness of the proposed basic and large model, and outstanding mIoU results have been achieved. All codes are available on https://github.com/GtLinyer/LOANet.
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Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin lymphoma. Up to 40% of patients with DLBCL display refractory disease or relapse after standard chemotherapy treatment (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone [R-CHOP]), leading to significant morbidity and mortality. The molecular mechanisms of chemoresistance in DLBCL remain incompletely understood. Using a cullin-really interesting new gene (RING) ligase-based CRISPR-Cas9 library, we identify that inactivation of the E3 ubiquitin ligase KLHL6 promotes DLBCL chemoresistance. Furthermore, proteomic approaches helped identify KLHL6 as a novel master regulator of plasma membrane-associated NOTCH2 via proteasome-dependent degradation. In CHOP-resistant DLBCL tumors, mutations of NOTCH2 result in a protein that escapes the mechanism of ubiquitin-dependent proteolysis, leading to protein stabilization and activation of the oncogenic RAS signaling pathway. Targeting CHOP-resistant DLBCL tumors with the phase 3 clinical trial molecules nirogacestat, a selective γ-secretase inhibitor, and ipatasertib, a pan-AKT inhibitor, synergistically promotes DLBCL destruction. These findings establish the rationale for therapeutic strategies aimed at targeting the oncogenic pathway activated in KLHL6- or NOTCH2-mutated DLBCL.
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Resistencia a Medicamentos Antineoplásicos , Linfoma Difuso de Grandes Células B , Humanos , Resistencia a Medicamentos Antineoplásicos/genética , Ubiquitina , Proteômica , Recidiva Local de Neoplasia/tratamento farmacológico , Rituximab/uso terapêutico , Vincristina , Ciclofosfamida , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/genética , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Prednisona , Mutação , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Receptor Notch2/genéticaRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Pulmonary artery hypertension (PAH) is a progressive and fatal lung disease of multifactorial etiology, which arouses an enhanced interest in PAH disease therapy. Modified Fangji Huangqi decoction (MFJHQ), a traditional Chinese medicine (TCM) formula, has a crucial role in the treatment of PAH. However, the pharmacological roles and mechanisms of MFJHQ on PAH remain unknown. AIM OF THE STUDY: To investigate the effects and potential mechanism of MFJHQ on pulmonary vascular remodeling in PAH. MATERIAL AND METHODS: Ultra-performance liquid chromatography (UPLC) was employed to quantitate the principal components in MFJHQ. Rats were treated with MFJHQ by gavage for final 2 weeks in monocrotaline (MCT)-induced PAH rats. RNA-sequencing and network pharmacology analysis were performed to explore the potential mechanism. The primary rat pulmonary artery smooth muscle cells (PASMCs) were utilized to evaluate the regulatory effect of MFJHQ in vitro. RESULTS: Seven active components from MFJHQ were quantitated by UPLC. In rats with MCT-induced PAH, MFJHQ treatment significantly improved hemodynamic parameters, right ventricular hypertrophy index, lung function, and attenuated pulmonary vascular remodeling. Mechanistically, we further confirmed that MFJHQ inhibits MCT-induced phosphatidylinositide 3-kinases/protein kinase B (PI3K/Akt) pathway predicated by network pharmacology and RNA-sequencing analysis to reduce the proliferation of pulmonary arteries and promote pulmonary artery apoptosis in lung tissues. Additionally, MFJHQ hindered the proliferation and migration, and accelerated apoptosis in PDGF-BB-induced PASMCs in vitro, which can be enhanced by the presence of the PI3K inhibitor LY294002. CONCLUSIONS: Our results indicated that MFJHQ inhibited MCT-induced pulmonary vascular remodeling by decreasing proliferation and migration of PASMCs and promoting PASMC apoptosis through PI3K/Akt pathway, which provides a novel treatment option for PAH with multi-targeting mechanisms inspired by TCM theory.
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Hipertensão Pulmonar , Proteínas Proto-Oncogênicas c-akt , Ratos , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Artéria Pulmonar , Hipertensão Pulmonar/induzido quimicamente , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/metabolismo , Ratos Sprague-Dawley , Fosfatidilinositol 3-Quinases/metabolismo , Remodelação Vascular , Proliferação de Células , Miócitos de Músculo Liso/metabolismo , Monocrotalina/toxicidade , Monocrotalina/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Apoptose , RNA/efeitos adversos , RNA/metabolismoRESUMO
Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are life-threatening symptoms in Coronavirus Disease 2019 (COVID-19) patients. Xuanfei Baidu Decoction (XFBD) is a recommend first-line traditional Chinese medicine (TCM) formula therapeutic strategy for COVID-19 patients. Prior studies demonstrated the pharmacological roles and mechanisms of XFBD and its derived effective components against inflammation and infections through multiple model systems, which provided the biological explanations for its clinical use. Our previous work revealed that XFBD inhibited macrophages and neutrophils infiltration via PD-1/IL17A signaling pathway. However, the subsequent biological processes are not well elucidated. Here, we proposed a hypothesis that XFBD can regulate the neutrophils-mediated immune responses, including neutrophil extracellular traps (NETs) formation and the generation of platelet-neutrophil aggregates (PNAs) after XFBD administration in lipopolysaccharide (LPS)-induced ALI mice. The mechanism behind it was also firstly explained, that is XFBD regulated NETs formation via CXCL2/CXCR2 axis. Altogether, our findings demonstrated the sequential immune responses of XFBD after inhibiting neutrophils infiltration, as well as shedding light on exploiting the therapy of XFBD targeting neutrophils to ameliorate ALI during the clinical course.
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Lesão Pulmonar Aguda , COVID-19 , Armadilhas Extracelulares , Animais , Camundongos , COVID-19/metabolismo , Lesão Pulmonar Aguda/metabolismo , Neutrófilos , Transdução de SinaisRESUMO
Liver metastasis is a major cause of death in gastric cancer patients, but the underlying mechanisms are poorly understood. Through a combination of in vivo screening and transcriptome profiling followed by quantitative RT-PCR and tissue array analyses, we found that mitogen-activated protein kinase 4 (MAPK4) downregulation in gastric cancer tissues from patients is significantly associated with liver metastasis and poor prognosis. The knockdown of MAPK4 in gastric cancer cells promotes liver metastasis in orthotopic mouse models. MAPK4 depletion in gastric cancer cells induces the secretion of macrophage migration inhibitory factor (MIF) to polarize tumor-associated macrophages (TAMs) in orthotopic xenograft tumors. Moreover, TAMs activate epithelial-mesenchymal transition of gastric cancer cells to suppress MAPK4 expression, which further increases MIF secretion to polarize TAMs. Taken together, our results suggest a previously undescribed positive feedback loop between cancer cells and macrophages mediated by MAPK4 silencing that facilitates gastric cancer liver metastasis.
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Neoplasias Hepáticas , Neoplasias Gástricas , Animais , Camundongos , Humanos , Linhagem Celular Tumoral , Neoplasias Gástricas/patologia , Retroalimentação , Macrófagos/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neoplasias Hepáticas/patologia , Transição Epitelial-Mesenquimal/genética , Metástase Neoplásica/patologia , Movimento Celular , Regulação Neoplásica da Expressão GênicaRESUMO
Nucleophosmin (NPM1) is a ubiquitously expressed nucleolar protein with a wide range of biological functions. In 30% of acute myeloid leukemia (AML), the terminal exon of NPM1 is often found mutated, resulting in the addition of a nuclear export signal and a shift of the protein to the cytoplasm (NPM1c). AMLs carrying this mutation have aberrant expression of the HOXA/B genes, whose overexpression leads to leukemogenic transformation. Here, for the first time, we comprehensively prove that NPM1c binds to a subset of active gene promoters in NPM1c AMLs, including well-known leukemia-driving genes-HOXA/B cluster genes and MEIS1. NPM1c sustains the active transcription of key target genes by orchestrating a transcription hub and maintains the active chromatin landscape by inhibiting the activity of histone deacetylases. Together, these findings reveal the neomorphic function of NPM1c as a transcriptional amplifier for leukemic gene expression and open up new paradigms for therapeutic intervention. SIGNIFICANCE: NPM1 mutation is the most common mutation in AML, yet the mechanism of how the mutant protein results in AML remains unclear. Here, for the first time, we prove mutant NPM1 directly binds to active chromatin regions and hijacks the transcription of AML-driving genes. See related article by Uckelmann et al., p. 746. This article is highlighted in the In This Issue feature, p. 517.
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Leucemia Mieloide Aguda , Nucleofosmina , Humanos , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Leucemia Mieloide Aguda/tratamento farmacológico , Mutação , Cromatina/genéticaRESUMO
Growing evidence suggests prevalence of transcriptional condensates on chromatin, yet their mechanisms of formation and functional significance remain largely unclear. In human cancer, a series of mutations in the histone acetylation reader ENL create gain-of-function mutants with increased transcriptional activation ability. Here, we show that these mutations, clustered in ENL's structured acetyl-reading YEATS domain, trigger aberrant condensates at native genomic targets through multivalent homotypic and heterotypic interactions. Mechanistically, mutation-induced structural changes in the YEATS domain, ENL's two disordered regions of opposing charges, and the incorporation of extrinsic elongation factors are all required for ENL condensate formation. Extensive mutagenesis establishes condensate formation as a driver of oncogenic gene activation. Furthermore, expression of ENL mutants beyond the endogenous level leads to non-functional condensates. Our findings provide new mechanistic and functional insights into cancer-associated condensates and support condensate dysregulation as an oncogenic mechanism.
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Neoplasias , Corpos Nucleares , Humanos , Domínios Proteicos , Cromatina/genética , Mutação , Neoplasias/genéticaRESUMO
The chromatin reader eleven-nineteen leukemia (ENL) has been identified as a critical dependency in acute myeloid leukemia (AML), but its therapeutic potential remains unclear. We describe a potent and orally bioavailable small-molecule inhibitor of ENL, TDI-11055, which displaces ENL from chromatin by blocking its YEATS domain interaction with acylated histones. Cell lines and primary patient samples carrying MLL rearrangements or NPM1 mutations are responsive to TDI-11055. A CRISPR-Cas9-mediated mutagenesis screen uncovers an ENL mutation that confers resistance to TDI-11055, validating the compound's on-target activity. TDI-11055 treatment rapidly decreases chromatin occupancy of ENL-associated complexes and impairs transcription elongation, leading to suppression of key oncogenic gene expression programs and induction of differentiation. In vivo treatment with TDI-11055 blocks disease progression in cell line- and patient-derived xenograft models of MLL-rearranged and NPM1-mutated AML. Our results establish ENL displacement from chromatin as a promising epigenetic therapy for molecularly defined AML subsets and support the clinical translation of this approach. SIGNIFICANCE: AML is a poor-prognosis disease for which new therapeutic approaches are desperately needed. We developed an orally bioavailable inhibitor of ENL, demonstrated its potent efficacy in MLL-rearranged and NPM1-mutated AML, and determined its mechanisms of action. These biological and chemical insights will facilitate both basic research and clinical translation. This article is highlighted in the In This Issue feature, p. 2483.