Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
1.
EMBO J ; 41(16): e110636, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35638332

RESUMO

Activation of the T-cell antigen receptor (TCR)-CD3 complex is critical to induce the anti-tumor response of CD8+ T cells. Here, we found that disulfiram (DSF), an FDA-approved drug previously used to treat alcohol dependency, directly activates TCR signaling. Mechanistically, DSF covalently binds to Cys20/Cys23 residues of lymphocyte-specific protein tyrosine kinase (LCK) and enhances its tyrosine 394 phosphorylation, thereby promoting LCK kinase activity and boosting effector T cell function, interleukin-2 production, metabolic reprogramming, and proliferation. Furthermore, our in vivo data revealed that DSF promotes anti-tumor immunity against both melanoma and colon cancer in mice by activating CD8+ T cells, and this effect was enhanced by anti-PD-1 co-treatment. We conclude that DSF directly activates LCK-mediated TCR signaling to induce strong anti-tumor immunity, providing novel molecular insights into the therapeutic effect of DSF on cancer.


Assuntos
Dissulfiram , Proteína Tirosina Quinase p56(lck) Linfócito-Específica , Animais , Linfócitos T CD8-Positivos , Dissulfiram/farmacologia , Ativação Linfocitária , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/metabolismo , Camundongos , Fosforilação , Receptores de Antígenos de Linfócitos T/metabolismo , Transdução de Sinais
2.
Artigo em Inglês | MEDLINE | ID: mdl-38804044

RESUMO

Epigenetic modifications play an important role in cellular senescence, and enhancer of zeste homolog 2 (EZH2) is a key methyltransferase involved in epigenetic remodeling in multiple myeloma (MM) cells. We have previously demonstrated that GSK126, a specific EZH2 inhibitor, exhibits anti-MM therapeutic efficacy and safety in vivo and in vitro; however, its specific mechanism remains unclear. This study shows that GSK126 induces cellular senescence in MM, which is characterized by the accumulation of senescence-associated heterochromatin foci (SAHF) and p21, and increased senescence-associated ß galactosidase activity. Furthermore, EZH2 is inhibited in ribonucleotide reductase regulatory subunit M2 (RRM2) overexpression OCI-MY5 and RPMI-8226 cells. RRM2 overexpression inhibits the methyltransferase function of EZH2 and promotes its degradation through the ubiquitin-proteasome pathway, thereby inducing cellular senescence. In this senescence model, Lamin B1, a key component of the nuclear envelope and a marker of senescence, does not decrease but instead undergoes aberrant accumulation. Meanwhile, phosphorylation of extracellular signal-regulated protein kinase (ERK1/2) is significantly increased. The inhibition of ERK1/2 phosphorylation in turn partially restores Lamin B1 level and alleviates senescence. These findings suggest that EZH2 inhibition increases Lamin B1 level and induces senescence by promoting ERK1/2 phosphorylation. These data indicate that EZH2 plays an important role in MM cellular senescence and provide insights into the relationships among Lamin B1, p-ERK1/2, and cellular senescence.

3.
Chem Sci ; 14(2): 372-378, 2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36687345

RESUMO

Selective C(sp3)-S bond breaking and transformation remains a particularly important, yet challenging goal in synthetic chemistry. Over the past few decades, transition metal-catalyzed cross-coupling reactions through the cleavage of C(sp3)-S bonds provided a powerful platform for the construction of target molecules. In contrast, the selective activation of widespread C(sp3)-S bonds is rarely studied and remains underdeveloped, even under relatively harsh conditions. Herein, a radical-mediated electrochemical strategy capable of selectively activating C(sp3)-S bonds is disclosed, offering an unprecedented method for the synthesis of valuable disulfides from widespread thioethers. Importantly, compared with conventional transition-metal catalyzed C-S bond breaking protocols, this method features mild, catalyst- and oxidant-free reaction conditions, as well excellent chemoselectivity towards C(sp3)-S bonds. Preliminary mechanistic studies reveal that sulfur radical species are involved in the reaction pathway and play an essential role in controlling the site-selectivity.

4.
J Drug Target ; 31(9): 962-975, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37772906

RESUMO

Neutrophil extracellular traps (NETs) play a crucial role in breast cancer metastasis. However, the therapeutic target of NETs in breast cancer metastasis is still unknown. Using a natural metabolite library and single-cell sequencing data analysis, we identified resveratrol (RES), a polyphenolic natural phytoalexin, and agonist of silent information regulator-1 (SIRT1) that suppressed NETs formation after cathepsin C (CTSC) treatment. In vivo, RES significantly hindered breast cancer metastasis in a murine orthotopic 4T1 breast cancer model. Serum levels of myeloperoxidase-DNA and neutrophil elastase-DNA in mouse breast cancer model were significantly lower after RES treatment. Correspondingly, the tumour infiltrated CD8+T cells in the lungs increased after the treatment. Mechanistically, RES targets SIRT1 in neutrophils and significantly inhibits the citrullination of histones H3, which is essential for chromatin decondensation and NETs formation. Furthermore, we identified that the NETs were suppressed by RES in bone marrow neutrophils after CTSC treatment, while specific deficiency of SIRT1 in neutrophils promoted NETs formation and breast cancer to lung metastasis. Thus, our results revealed that RES could be potentially identified as a viable therapeutic drug to prevent neutrophil cell death and breast cancer metastasis.


Assuntos
Armadilhas Extracelulares , Neoplasias Pulmonares , Animais , Camundongos , Armadilhas Extracelulares/metabolismo , Resveratrol/farmacologia , Sirtuína 1/metabolismo , Pulmão , Neoplasias Pulmonares/patologia , DNA
5.
Nat Commun ; 14(1): 872, 2023 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-36797275

RESUMO

Although extracellular DNA is known to form immune complexes (ICs) with autoantibodies in systemic lupus erythematosus (SLE), the mechanisms leading to the release of DNA from cells remain poorly characterized. Here, we show that the pore-forming protein, gasdermin D (GSDMD), is required for nuclear DNA and mitochondrial DNA (mtDNA) release from neutrophils and lytic cell death following ex vivo stimulation with serum from patients with SLE and IFN-γ. Mechanistically, the activation of FcγR downregulated Serpinb1 following ex vivo stimulation with serum from patients with SLE, leading to spontaneous activation of both caspase-1/caspase-11 and cleavage of GSDMD into GSDMD-N. Furthermore, mtDNA oxidization promoted GSDMD-N oligomerization and cell death. In addition, GSDMD, but not peptidyl arginine deiminase 4 is necessary for extracellular mtDNA release from low-density granulocytes from SLE patients or healthy human neutrophils following incubation with ICs. Using the pristane-induced lupus model, we show that disease severity is significantly reduced in mice with neutrophil-specific Gsdmd deficiency or following treatment with the GSDMD inhibitor, disulfiram. Altogether, our study highlights an important role for oxidized mtDNA in inducing GSDMD oligomerization and pore formation. These findings also suggest that GSDMD might represent a possible therapeutic target in SLE.


Assuntos
Lúpus Eritematoso Sistêmico , Serpinas , Animais , Humanos , Camundongos , Caspase 1/metabolismo , DNA Mitocondrial/metabolismo , Gasderminas , Neutrófilos , Proteínas de Ligação a Fosfato/metabolismo , Serpinas/metabolismo , Multimerização Proteica
6.
J Immunol Res ; 2022: 2756611, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36281357

RESUMO

Objective: Cuproptosis is a newly discovered copper-independent cell death modality, and limited evidence suggests the critical implications in human cancers. Nonetheless, the clinical impacts of cuproptosis-relevant lncRNAs in lung adenocarcinoma (LUAD) remain largely ill-defined. The present study was aimed at defining a cuproptosis-relevant lncRNA signature for LUAD and discuss the clinical utility. Methods: We collected transcriptome expression profiling, clinical information, somatic mutation, and copy number variations from TCGA-LUAD cohort retrospectively. The genetic alterations of cuproptosis genes were systematically assessed across LUAD, and cuproptosis-relevant lncRNAs were screened for defining a LASSO prognostic model. Genomic alterations, immunological and stemness features, and therapeutic sensitivity were studied with a series of computational approaches. Results: Cuproptosis genes displayed aberrant expression and widespread genomic alterations across LUAD, potentially modulated by m6A/m5C/m1A RNA modification mechanisms. We defined a cuproptosis-relevant lncRNA signature, with a reliable efficacy in predicting clinical outcomes. High-risk subset displayed higher somatic mutations, CNVs, TMB, SNV neoantigens, aneuploidy score, CTA score, homologous recombination defects, and intratumor heterogeneity, cytolytic activity, CD8+ T effector, and antigen processing machinery, proving that this subset might benefit from immunotherapy. Increased stemness indexes and activity of oncogenic pathways might contribute to undesirable prognostic outcomes for high-risk subset. Additionally, high-risk patients generally exhibited higher response to chemotherapeutic agents (cisplatin, etc.). We also predicted several small molecule compounds (GSK461364, KX2-391, etc.) for treating this subset. Conclusion: Accordingly, this cuproptosis-relevant lncRNA signature offers an efficient approach to identify and characterize diverse prognosis, genomic alterations, and treatment outcomes in LUAD, thus potentially assisting personalized therapy.


Assuntos
Adenocarcinoma , Apoptose , Neoplasias Pulmonares , RNA Longo não Codificante , Humanos , Adenocarcinoma/genética , Biomarcadores Tumorais/genética , Cisplatino , Cobre , Variações do Número de Cópias de DNA , Regulação Neoplásica da Expressão Gênica , Genômica , Pulmão/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Estudos Retrospectivos , RNA Longo não Codificante/genética , Curva ROC
7.
Science ; 373(6555): 692-696, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34353954

RESUMO

Incorporating passive radiative cooling structures into personal thermal management technologies could effectively defend humans against intensifying global climate change. We show that large-scale woven metafabrics can provide high emissivity (94.5%) in the atmospheric window and high reflectivity (92.4%) in the solar spectrum because of the hierarchical-morphology design of the randomly dispersed scatterers throughout the metafabric. Through scalable industrial textile manufacturing routes, our metafabrics exhibit desirable mechanical strength, waterproofness, and breathability for commercial clothing while maintaining efficient radiative cooling ability. Practical application tests demonstrated that a human body covered by our metafabric could be cooled ~4.8°C lower than one covered by commercial cotton fabric. The cost-effectiveness and high performance of our metafabrics present substantial advantages for intelligent garments, smart textiles, and passive radiative cooling applications.

8.
Onco Targets Ther ; 12: 5979-5988, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31440059

RESUMO

Background and aim: Lung squamous cell carcinoma (LUSC), is a pathological subtype of lung cancer, accounting for 30% of the lung cancers. A reliable model was constructed, based on the whole gene expression profiles, to predict the prognosis of patients with LUSC. Methods: The RNA-Seq data of LUSC was downloaded from the TCGA database, and differentially expressed genes (p<0.05, |log2fold change| >1) were screened out. By univariate and multivariate Cox regression analysis, we identified seven prognosis-related genes. Then, we established a risk score staging system to predict the prognosis of patients with LUSC. Compared with other clinical parameters, the risk score was an independent prognostic factor and had a better performance in predicting prognosis. Finally, GSEA analysis was carried out to determine the enrichment pathway significantly. The risk score models were established by Cox proportional hazard regression analysis; the ROC curve was applied to test the performance of risk score model. All the statistical analysis was accomplished by R packages. Results: In this study, a model was constructed to predict prognosis, which contains seven genes: CSRNP1, CLEC18B, MIR27A, AC130456.4, DEFA6, ARL14EPL, and ZFP42. Based on the model, the risk score of each patient was calculated with LUSC (hazard ratio [HR]=2.673, 95% CI=1.871-3.525). It was found that the risk score can distinguish high-risk and low-risk groups in prognosis of LUSC patients, independently. Furthermore, the model was validated by ROC curves in the testing dataset and the whole dataset. Lastly, by gene set enrichment analysis (GSEA), we showed the main enrichment pathways were DNA damage stimulus, DNA repair, and DNA replication. It was suggested that the risk score may provide a new and reliable method for prognosis prediction. Conclusion: The results of this study suggested that the risk score based on seven-genes could indicate a promising and independent prognostic biomarker for LUSC patients.

SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa