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1.
EMBO Rep ; 23(6): e53932, 2022 06 07.
Article in English | MEDLINE | ID: mdl-35403787

ABSTRACT

Aberrant activation of stimulator of interferon genes (STING) is tightly associated with multiple types of disease, including cancer, infection, and autoimmune diseases. However, the development of STING modulators for the therapy of STING-related diseases is still an unmet clinical need. We employed a high-throughput screening approach based on the interaction of small-molecule chemical compounds with recombinant STING protein to identify functional STING modulators. Intriguingly, the cyclin-dependent protein kinase (CDK) inhibitor Palbociclib was found to directly bind STING and inhibit its activation in both mouse and human cells. Mechanistically, Palbociclib targets Y167 of STING to block its dimerization, its binding with cyclic dinucleotides, and its trafficking. Importantly, Palbociclib alleviates autoimmune disease features induced by dextran sulphate sodium or genetic ablation of three prime repair exonuclease 1 (Trex1) in mice in a STING-dependent manner. Our work identifies Palbociclib as a novel pharmacological inhibitor of STING that abrogates its homodimerization and provides a basis for the fast repurposing of this Food and Drug Administration-approved drug for the therapy of autoinflammatory diseases.


Subject(s)
Autoimmune Diseases , Neoplasms , Animals , Autoimmune Diseases/metabolism , Membrane Proteins/genetics , Membrane Proteins/metabolism , Mice , Neoplasms/metabolism , Piperazines/pharmacology , Pyridines/pharmacology , Pyridines/therapeutic use
2.
Entropy (Basel) ; 26(1)2024 Jan 02.
Article in English | MEDLINE | ID: mdl-38248173

ABSTRACT

This paper introduces the notion of multi-sensitivity with respect to a vector within the context of non-autonomous dynamical systems on uniform spaces and provides insightful results regarding N-sensitivity and strongly multi-sensitivity, along with their behaviors under various conditions. The main results established are as follows: (1) For a k-periodic nonautonomous dynamical system on a Hausdorff uniform space (S,U), the system (S,fk∘⋯∘f1) exhibits N-sensitivity (or strongly multi-sensitivity) if and only if the system (S,f1,∞) displays N-sensitivity (or strongly multi-sensitivity). (2) Consider a finitely generated family of surjective maps on uniform space (S,U). If the system (S,f1,∞) is N-sensitive, then the system (S,fk,∞) is also N-sensitive. When the family f1,∞ is feebly open, the converse statement holds true as well. (3) Within a finitely generated family on uniform space (S,U), N-sensitivity (and strongly multi-sensitivity) persists under iteration. (4) We present a sufficient condition under which an nonautonomous dynamical system on infinite Hausdorff uniform space demonstrates N-sensitivity.

3.
Small ; 15(8): e1804947, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30690874

ABSTRACT

Semiconductor quantum dots (QDs) are among the most promising next-generation optoelectronic materials. QDs are generally obtained through either epitaxial or colloidal growth and carry the promise for solution-processed high-performance optoelectronic devices such as light-emitting diodes (LEDs), solar cells, etc. Herein, a straightforward approach to synthesize perovskite QDs and demonstrate their applications in efficient LEDs is reported. The perovskite QDs with controllable crystal sizes and properties are in situ synthesized through one-step spin-coating from perovskite precursor solutions followed by thermal annealing. These perovskite QDs feature size-dependent quantum confinement effect (with readily tunable emissions) and radiative monomolecular recombination. Despite the substantial structural inhomogeneity, the in situ generated perovskite QDs films emit narrow-bandwidth emission and high color stability due to efficient energy transfer between nanostructures that sweeps away the unfavorable disorder effects. Based on these materials, efficient LEDs with external quantum efficiencies up to 11.0% are realized. This makes the technologically appealing in situ approach promising for further development of state-of-the-art LED systems and other optoelectronic devices.

4.
Proteomics ; 18(15): e1700388, 2018 08.
Article in English | MEDLINE | ID: mdl-29901268

ABSTRACT

Non-small cell lung cancer (NSCLC) patients carrying EGFR activating mutations treated with gefitinib, a tyrosine kinase inhibitor, will develop drug resistance. Ubiquitylation is one of major posttranslational modifications of proteins affecting the stability or function of proteins. However, the role of protein ubiquitylation in gefitinib resistance is poorly understood. To systematically identify the global change in protein expression and ubiquitylation during gefitinib resistance, a quantitative global proteome and ubiquitylome study in a pair of gefitinib-resistant and sensitive NSCLC cells is carried out. Altogether, changes in expression of 3773 proteins are quantified, and changes in ubiquitylation of 2893 lysine sites in 1415 proteins are measured in both cells. Interestingly, lysosomal and endocytic pathways, which are involved in autophagy regulation, are enriched with upregulated proteins or ubiquitylated proteins in gefitinib-resistant cells. In addition, HMGA2 overexpression or ALOX5 knockdown suppresses gefitinib resistance in NSCLC cells by inhibiting autophagy. Overall, these results reveal the previously unknown global ubiquitylome and proteomic features associated with gefitinib resistance, uncover the opposing roles of HMGA2 or ALOX5 in regulating gefitinib resistance and autophagy, and will help to identify new therapeutic targets in overcoming gefitinib resistance.


Subject(s)
Carcinoma, Non-Small-Cell Lung/metabolism , Drug Resistance, Neoplasm , Gefitinib/pharmacology , Lysosomes/metabolism , Proteome/analysis , Ubiquitin/metabolism , Arachidonate 5-Lipoxygenase/chemistry , Arachidonate 5-Lipoxygenase/genetics , Arachidonate 5-Lipoxygenase/metabolism , Autophagy , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/pathology , Endosomes/metabolism , Gene Ontology , HMGA2 Protein/genetics , HMGA2 Protein/metabolism , Humans , Lung Neoplasms/drug therapy , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Mass Spectrometry , Protein Kinase Inhibitors/pharmacology , Protein Processing, Post-Translational , Proteome/drug effects , Tumor Cells, Cultured , Ubiquitination
5.
J Biol Chem ; 291(5): 2087-106, 2016 Jan 29.
Article in English | MEDLINE | ID: mdl-26504080

ABSTRACT

Tumor invasiveness depends on the ability of tumor cells to breach endothelial barriers. In this study, we investigated the mechanism by which the adhesion of melanoma cells to endothelium regulates adherens junction integrity and modulates tumor transendothelial migration (TEM) by initiating thrombin generation. We found that the B-Raf(V600E) mutation in metastatic melanoma cells up-regulated tissue factor (TF) expression on cell membranes and promoted thrombin production. Co-culture of endothelial monolayers with metastatic melanoma cells mediated the opening of inter-endothelial spaces near melanoma cell contact sites in the presence of platelet-free plasma (PFP). By using small interfering RNA (siRNA), we demonstrated that B-Raf(V600E) and TF silencing attenuated the focal disassembly of adherens junction induced by tumor contact. Vascular endothelial-cadherin (VE-cadherin) disassembly was dependent on phosphorylation of p120-catenin on Ser-879 and VE-cadherin on Tyr-658, Tyr-685, and Tyr-731, which can be prevented by treatment with the thrombin inhibitor, hirudin, or by silencing the thrombin receptor, protease-activated receptor-1, in endothelial cells. We also provided strong evidence that tumor-derived thrombin enhanced melanoma TEM by inducing ubiquitination-coupled VE-cadherin internalization, focal adhesion formation, and actin assembly in endothelium. Confocal microscopic analysis of tumor TEM revealed that junctions transiently opened and resealed as tumor cells accomplished TEM. In addition, in the presence of PFP, tumor cells preferentially transmigrated via paracellular routes. PFP supported melanoma transmigration under shear conditions via a B-Raf(V600E)-thrombin-dependent mechanism. We concluded that the activation of thrombin generation by cancer cells in plasma is an important process regulating melanoma extravasation by disrupting endothelial junction integrity.


Subject(s)
Endothelium, Vascular/metabolism , Melanoma/metabolism , Proto-Oncogene Proteins B-raf/metabolism , Skin Neoplasms/metabolism , Thrombin/metabolism , Thromboplastin/metabolism , Antigens, CD/metabolism , Cadherins/metabolism , Cell Adhesion , Cell Line, Tumor , Cell Membrane/metabolism , Cell Movement , Electric Impedance , Gene Silencing , Human Umbilical Vein Endothelial Cells , Humans , Mutation , Neoplasm Metastasis , Permeability , Phosphorylation , Plasma/metabolism , RNA, Small Interfering/metabolism , Ubiquitination
6.
Adv Mater ; : e2407652, 2024 Sep 12.
Article in English | MEDLINE | ID: mdl-39267373

ABSTRACT

While significant efforts have been devoted to optimize the thin-film stoichiometry and processing of perovskites for applications in photovoltaic and light-emitting diodes, there is a noticeable lack of emphasis on tailoring them for lasing applications. In this study, it is revealed that thin films engineered for efficient light-emitting diodes, with passivation of deep and shallow trap states and a tailored energetic landscape directing carriers toward low-energy emitting states, may not be optimal for light amplification systems. Instead, amplified spontaneous emission (ASE) is found to be sustained by shallow defects, driven by the positive correlation between the ASE threshold and the ratio of carrier injection rate in the emissive state to the recombination rate of excited carriers. This insight has informed the development of an optimized perovskite thin film and laser device exhibiting a low threshold (≈ 60 µJ cm-2) and stable ASE emission exceeding 21 hours in ambient conditions.

7.
Cell Physiol Biochem ; 31(1): 56-65, 2013.
Article in English | MEDLINE | ID: mdl-23343715

ABSTRACT

BACKGROUND/AIMS: MicroRNAs (miRNAs) play important roles in tumorigenesis. We investigated the roles and mechanisms of miR-138 in human non-small cell lung cancer (NSCLC). METHODS: The expression of miR-138 was first examined in NSCLC cell lines and tumour tissues by real-time PCR The in vitro and in vivo functional effect of miR-138 was examined further. A luciferase reporter assay was conducted to confirm target association between miR-138 and the enhancer of zeste homolog 2 (EZH2). RESULTS: miR-138 was frequently downregulated in NSCLC cells and tissues. Overexpression of miR-138 inhibited proliferation of NSCLC cells in vitro and tumor growth in vivo. The EZH2 oncogene, which is often overexpressed in various human cancers and acts as an important regulator of cell growth and tumor invasion, was identified as a novel target of miR-138. miR-138 can bind to the 3' untranslated region (3' UTR) of EZH2 and suppress the expression of EZH2 at both mRNA and protein levels. Furthermore, knockdown of EZH2 phenocopied the tumor suppressive effects of miR-138 in cell models, whereas ectopic expression of EZH2 rescued the suppressive effects of miR-138. CONCLUSION: These findings define a tumor suppressor function for miR-138 in NSCLC and further suggest that miR-138 may represent a potential therapeutic target for NSCLC patients.


Subject(s)
MicroRNAs/metabolism , Polycomb Repressive Complex 2/metabolism , 3' Untranslated Regions , Animals , Carcinoma, Non-Small-Cell Lung/metabolism , Carcinoma, Non-Small-Cell Lung/pathology , Cell Line, Tumor , Cell Proliferation , Cell Transformation, Neoplastic , Down-Regulation , Enhancer of Zeste Homolog 2 Protein , G1 Phase Cell Cycle Checkpoints , Humans , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Male , Mice , Mice, Nude , MicroRNAs/genetics , Polycomb Repressive Complex 2/genetics , RNA Interference , RNA, Messenger/metabolism , RNA, Small Interfering/metabolism , Transplantation, Heterologous
8.
Front Endocrinol (Lausanne) ; 14: 1213465, 2023.
Article in English | MEDLINE | ID: mdl-37876543

ABSTRACT

Objective: Hyperthyroidism in Chinese children is relatively high and has been increasing in recent years, which has a significant impact on their healthy development. Hyperthyroidism is a polygenic disorder that presents greater challenges in terms of prediction and treatment than monogenic diseases. This study aims to elucidate the associated functions and gene sets of mutated genes in children with hyperthyroidism in terms of the gene ontology through GO enrichment analysis and in terms of biological signaling pathways through KEGG enrichment analysis, thereby enhancing our understanding of the expected effects of multiple mutated genes on hyperthyroidism in children. Methods: Whole-exome sequencing was performed on the DNA samples of children with hyperthyroidism. Screening for pathogenic genes related to hyperthyroidism in affected children was performed using the publicly available disease databases Malacards, MutationView, and Clinvar, and the functions and influences of the identified pathogenic genes were analyzed using statistical analysis and the gene enrichment approach. Results: Through GO enrichment analysis, it was found that the most significant gene ontology enrichment was the function "hormone activity" in terms of gene ontology molecular function. The corresponding mutated genes set that has common effects on hyperthyroidism in children included TG, CALCA, POMC, CGA, PTH, GHRL, FBN1, TRH, PRL, LEP, ADIPOQ, INS, GH1. The second most significant gene ontology enrichment was the function "response to peptide hormone" in terms of biological process. The corresponding mutated genes set that has common effects on hyperthyroidism in children included LRP6, TSC2, KANK1, COL1A1, CDKN1B, POMC, STAT1, MEN1, APC, GHRL, TSHR, GJB2, FBN1, GPT, LEP, ADIPOQ, INS, GH1. Through KEGG enrichment analysis, it was found that the most significant biological signaling pathway enrichment was the pathway "Thyroid hormone signaling pathway" function. The corresponding mutated genes set that has common effects on hyperthyroidism in children included NOTCH3, MYH7, TSC2, STAT1, MED13L, MAP2K2, SLCO1C1, SLC16A2, and THRB. The second most significant biological signaling pathway enrichment was the pathway "Hypertrophic cardiomyopathy" in terms of biological process. The corresponding mutated genes set that has common effects on hyperthyroidism in children included IGF1, CACNA1S, MYH7, IL6, TTN, CACNB2, LAMA2, and DMD. Conclusion: The mutated genes in children with hyperthyroidism were closely linked to function involved in "hormone activity" and "response to peptide hormone" in terms of the biological signaling pathway, and to the functional pathways involved in "Thyroid hormone signaling pathway" and "Hypertrophic cardiomyopathy" in terms of the biological signaling pathway.


Subject(s)
Cardiomyopathies , Hyperthyroidism , Organic Anion Transporters , Symporters , Humans , Child , Computational Biology , Pro-Opiomelanocortin , Hyperthyroidism/genetics , Thyroid Hormones , Cytoskeletal Proteins , Adaptor Proteins, Signal Transducing , Monocarboxylic Acid Transporters
9.
Front Bioeng Biotechnol ; 11: 1253048, 2023.
Article in English | MEDLINE | ID: mdl-37771575

ABSTRACT

The treatment of breast cancer (BC) is a serious challenge due to its heterogeneous nature, multidrug resistance (MDR), and limited therapeutic options. Nanoparticle-based drug delivery systems (NDDSs) represent a promising tool for overcoming toxicity and chemotherapy drug resistance in BC treatment. No bibliometric studies have yet been published on the research landscape of NDDS-based treatment of BC. In this review, we extracted data from 1,752 articles on NDDS-based treatment of BC published between 2012 and 2022 from the Web of Science Core Collection (WOSCC) database. VOSviewer, CiteSpace, and some online platforms were used for bibliometric analysis and visualization. Publication trends were initially observed: in terms of geographical distribution, China and the United States had the most papers on this subject. The highest contributing institution was Sichuan University. In terms of authorship and co-cited authorship, the most prolific author was Yu Zhang. Furthermore, Qiang Zhang and co-workers have made tremendous achievements in the field of NDDS-based BC treatment. The article titled "Nanomedicine in cancer therapy: challenges, opportunities, and clinical applications" had the most citations. The Journal of Controlled Release was one of the most active publishers in the field. "Global cancer statistics 2018: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries" was the most cited reference. We also analysed "hot" and cutting-edge research for NDDSs in BC treatment. There were nine topic clusters: "tumour microenvironment," "nanoparticles (drug delivery)," "breast cancer/triple-negative breast cancer," "combination therapy," "drug release (pathway)," "multidrug resistance," "recent advance," "targeted drug delivery", and "cancer nanomedicine." We also reviewed the core themes of research. In summary, this article reviewed the application of NDDSs in the treatment of BC.

10.
Adv Mater ; 35(8): e2209002, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36493461

ABSTRACT

Pure-red perovskite LEDs (PeLEDs) based on CsPb(Br/I)3 nanocrystals (NCs) usually suffer from a compromise in emission efficiency and spectral stability on account of the surface halide vacancies-induced nonradiative recombination loss, halide phase segregation, and self-doping effect. Herein, a "halide-equivalent" anion of benzenesulfonate (BS- ) is introduced into CsPb(Br/I)3 NCs as multifunctional additive to simultaneously address the above challenging issues. Joint experiment-theory characterizations reveal that the BS- can not only passivate the uncoordinated Pb2+ -related defects at the surface of NCs, but also increase the formation energy of halide vacancies. Moreover, because of the strong electron-withdrawing property of sulfonate group, electrons are expected to transfer from the CsPb(Br/I)3 NC to BS- for reducing the self-doping effect and altering the n-type behavior of CsPb(Br/I)3 NCs to near ambipolarity. Eventually, synergistic boost in device performance is achieved for pure-red PeLEDs with CIE coordinates of (0.70, 0.30) and a champion external quantum efficiency of 23.5%, which is one of the best value among the ever-reported red PeLEDs approaching to the Rec. 2020 red primary color. Moreover, the BS- -modified PeLED exhibits negligible wavelength shift under different operating voltages. This strategy paves an efficient way for improving the efficiency and stability of pure-red PeLEDs.

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