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The pleiotropic effect of cancer-associated fibroblasts (CAFs) on tumour progression depends on the environment. circFARP1 is critical for CAFs-induced gemcitabine (GEM) resistance in pancreatic cancer. Its specific role and mechanism in non-small cell lung cancer (NSCLC) have not been reported yet. We prepared a cancer-associated fibroblasts-conditioned medium (CAF-CM) to incubate the A549 cells. Quantitative real-time polymerase chain reaction was used to detect RNA levels. We detected protein expression by immunohistochemistry, immunocytochemistry, western blot and immunofluorescence. We also detected the targeting impact between circFARP1, miR-338-3p and SRY-box transcription factor 4 (SOX4) by using dual-luciferase reporter and RNA pull-down assays. We determined cell proliferation, migration and invasion capabilities through Cell Counting Kit-8 and transwell assays. In addition, we measured tumour volume and weight in vivo by establishing a xenograft tumour model. CircFARP1 levels were remarkably high in the CAFs. The transfection experiments found that circFARP1 downregulation in CAFs caused migration, proliferation and invasion inhibition of CAFs and A549 cells, whereas inhibiting miR-38-3p or overexpressing SOX4 in CAFs could significantly reverse the inhibition. In vivo study in nude mice confirmed that CAFs could promote NSCLC tumour growth and knockdown of circFARP1 could inhibit tumour growth of NSCLC, whereas miR-38-3p downregulation or SOX4 overexpression could significantly reverse the inhibition. circFARP1 promotes NSCLC development by stimulating miR-338-3p/SOX4 signalling axis to regulate CAFs.
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Fibroblastos Asociados al Cáncer , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , MicroARNs , Invasividad Neoplásica , ARN Circular , Factores de Transcripción SOXC , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Factores de Transcripción SOXC/genética , Factores de Transcripción SOXC/metabolismo , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Animales , ARN Circular/genética , ARN Circular/metabolismo , Fibroblastos Asociados al Cáncer/metabolismo , Fibroblastos Asociados al Cáncer/patología , Proliferación Celular/genética , Ratones , Células A549 , Metástasis de la Neoplasia , Movimiento Celular , Regulación Neoplásica de la Expresión Génica , Ratones Desnudos , MasculinoRESUMEN
Lung cancer is the leading cause of global cancer-related deaths. Platinum-based chemotherapy is the first-line treatment for the most common type of lung cancer, i.e., non-small-cell lung cancer (NSCLC), but its therapeutic efficiency is limited by chemotherapeutic resistance. Therefore, it is vital to develop effective therapeutic modalities that bypass the common molecular mechanisms associated with chemotherapeutic resistance. Ferroptosis is a form of non-apoptotic regulated cell death characterized by iron-dependent lipid peroxidation (LPO). Ferroptosis is crucial for the proper therapeutic efficacy of lung cancer-associated chemotherapies. If targeted as a novel therapeutic mechanism, ferroptosis modulators present new opportunities for increasing the therapeutic efficacy of lung cancer chemotherapy. Emerging studies have revealed that the pharmacological induction of ferroptosis using natural compounds boosts the efficacy of chemotherapy in lung cancer or drug-resistant cancer. In this review, we first discuss chemotherapeutic resistance (or chemoresistance) in lung cancer and introduce the core mechanisms behind ferroptosis. Then, we comprehensively summarize the small-molecule compounds sourced from traditional medicines that may boost the anti-tumor activity of current chemotherapeutic agents and overcome chemotherapeutic resistance in NSCLC. Cumulatively, we suggest that traditional medicines with ferroptosis-related anticancer activity could serve as a starting point to overcome chemotherapeutic resistance in NSCLC by inducing ferroptosis, highlighting new potential therapeutic regimens used to overcome chemoresistance in NSCLC.
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Anoikis, known as matrix detachment-induced apoptosis or detachment-induced cell death, is crucial for tissue development and homeostasis. Cancer cells develop means to evade anoikis, e.g. anoikis resistance, thereby allowing for cells to survive under anchorage-independent conditions. Uncovering the mechanisms of anoikis resistance will provide details about cancer metastasis, and potential strategies against cancer cell dissemination and metastasis. Here, we summarize the principal elements and core molecular mechanisms of anoikis and anoikis resistance. We discuss the latest progress of how anoikis and anoikis resistance are regulated in cancers. Furthermore, we summarize emerging data on selective compounds and nanomedicines, explaining how inhibiting anoikis resistance can serve as a meaningful treatment modality against cancers. Finally, we discuss the key limitations of this therapeutic paradigm and possible strategies to overcome them. In this review, we suggest that pharmacological modulation of anoikis and anoikis resistance by bioactive compounds could surmount anoikis resistance, highlighting a promising therapeutic regimen that could be used to overcome anoikis resistance in cancers.
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Anoicis , Antineoplásicos , Neoplasias , Anoicis/efectos de los fármacos , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Antineoplásicos/uso terapéutico , Antineoplásicos/farmacología , Animales , Resistencia a Antineoplásicos/efectos de los fármacos , Metástasis de la NeoplasiaRESUMEN
BACKGROUND: Nemonoxacin malate is a novel non-fluorinated quinolone for oral and intravenous (IV) administration. This phase 3, multicentre, randomised, double-blind, double-dummy, parallel-controlled clinical trial (NCT02205112) evaluated the efficacy and safety of IV nemonoxacin vs. levofloxacin for the treatment of community-acquired pneumonia (CAP) in adult patients. METHODS: Eligible patients were randomised to receive 500 mg nemonoxacin or levofloxacin via IV infusion, once daily for 7-14 days. The primary endpoint was the clinical cure rate at the test-of-cure (TOC) visit in the modified intent-to-treat (mITT) population. Secondary efficacy and safety were also compared between nemonoxacin and levofloxacin. RESULTS: Overall, 525 patients were randomised and treated with nemonoxacin (n = 349) or levofloxacin (n = 176). The clinical cure rate was 91.8% (279/304) for nemonoxacin and 85.7% (138/161) for levofloxacin in the mITT population (P > 0.05). The clinical efficacy of nemonoxacin was non-inferior to levofloxacin for treatment of CAP. Microbiological success rate with nemonoxacin was 88.8% (95/107) and with levofloxacin was 87.8% (43/49) (P > 0.05) at the TOC visit in the bacteriological mITT population. The incidence of drug-related adverse events (AEs) was 37.1% in the nemonoxacin group and 22.2% in the levofloxacin group. These AEs were mostly local reactions at the infusion site, nausea, elevated alanine aminotransferase/aspartate aminotransferase (ALT/AST), and QT interval prolongation. The nemonoxacin-related AEs were mostly mild and resolved after discontinuation of nemonoxacin. CONCLUSIONS: Nemonoxacin 500 mg IV once daily for 7-14 days is effective and safe and non-inferior to levofloxacin for treating CAP in adult patients.
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Antibacterianos , Infecciones Comunitarias Adquiridas , Levofloxacino , Quinolonas , Humanos , Infecciones Comunitarias Adquiridas/tratamiento farmacológico , Masculino , Femenino , Persona de Mediana Edad , Levofloxacino/uso terapéutico , Levofloxacino/efectos adversos , Levofloxacino/administración & dosificación , Método Doble Ciego , Antibacterianos/uso terapéutico , Antibacterianos/administración & dosificación , Antibacterianos/efectos adversos , Adulto , Anciano , Resultado del Tratamiento , Quinolonas/uso terapéutico , Quinolonas/administración & dosificación , Quinolonas/efectos adversos , Administración Intravenosa , Infusiones Intravenosas , Adulto Joven , Neumonía/tratamiento farmacológico , Neumonía Bacteriana/tratamiento farmacológico , Neumonía Bacteriana/microbiología , Anciano de 80 o más AñosRESUMEN
Tumor metastasis occurs in hepatocellular carcinoma (HCC), leading to tumor progression and therapeutic failure. Anoikis is a matrix detachment-induced apoptosis, also known as detachment-induced cell death, and mechanistically prevents tumor cells from escaping their native extracellular matrix to metastasize to new organs. Deciphering the regulators and mechanisms of anoikis in cancer metastasis is urgently needed to treat HCC. Several natural and synthetic products induce anoikis in HCC cells and in vivo models. Here, we first briefly summarize the current understanding of the molecular mechanisms of anoikis regulation and relevant regulators involved in HCC metastasis. Then we discuss the therapeutic potential of pharmacological induction of anoikis as a potential treatment against HCC. Finally, we discuss the key limitations of this therapeutic paradigm and propose possible strategies to overcome them. Cumulatively this review suggests that the pharmacological induction of anoikis can be used a promising therapeutic modality against HCC.
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Anoicis , Carcinoma Hepatocelular , Neoplasias Hepáticas , Anoicis/efectos de los fármacos , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Humanos , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Metástasis de la NeoplasiaRESUMEN
Bronchopulmonary dysplasia (BPD), a prevalent and chronic lung disease affecting premature newborns, results in vascular rarefaction and alveolar simplification. Although the vasculature has been recognized as a main player in this disease, the recently found capillary heterogeneity and cellular dynamics of endothelial subpopulations in BPD remain unclear. Here, we show Cap2 cells are damaged during neonatal hyperoxic injury, leading to their replacement by Cap1 cells which, in turn, significantly decline. Single-cell RNA-seq identifies the activation of numerous p53 target genes in endothelial cells, including Cdkn1a (p21). While global deletion of p53 results in worsened vasculature, endothelial-specific deletion of p53 reverses the vascular phenotype and improves alveolar simplification during hyperoxia. This recovery is associated with the emergence of a transitional EC state, enriched for oxidative stress response genes and growth factors. These findings implicate the p53 pathway in EC type transition during injury-repair and highlights the endothelial contributions to BPD.
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Cell plasticity theoretically extends to all possible cell types, but naturally decreases as cells differentiate, whereas injury-repair re-engages the developmental plasticity. Here we show that the lung alveolar type 2 (AT2)-specific transcription factor (TF), CEBPA, restricts AT2 cell plasticity in the mouse lung. AT2 cells undergo transcriptional and epigenetic maturation postnatally. Without CEBPA, both neonatal and mature AT2 cells reduce the AT2 program, but only the former reactivate the SOX9 progenitor program. Sendai virus infection bestows mature AT2 cells with neonatal plasticity where Cebpa mutant, but not wild type, AT2 cells express SOX9, as well as more readily proliferate and form KRT8/CLDN4+ transitional cells. CEBPA promotes the AT2 program by recruiting the lung lineage TF NKX2-1. The temporal change in CEBPA-dependent plasticity reflects AT2 cell developmental history. The ontogeny of AT2 cell plasticity and its transcriptional and epigenetic mechanisms have implications in lung regeneration and cancer.
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Células Epiteliales Alveolares , Proteínas Potenciadoras de Unión a CCAAT , Plasticidad de la Célula , Animales , Ratones , Células Epiteliales Alveolares/metabolismo , Células Epiteliales Alveolares/citología , Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Proteínas Potenciadoras de Unión a CCAAT/genética , Diferenciación Celular , Plasticidad de la Célula/genética , Proliferación Celular , Epigénesis Genética , Pulmón/metabolismo , Lesión Pulmonar/patología , Lesión Pulmonar/metabolismo , Lesión Pulmonar/genética , Ratones Endogámicos C57BL , Ratones Noqueados , Regeneración , Virus Sendai/genética , Virus Sendai/fisiología , Factor de Transcripción SOX9/metabolismo , Factor de Transcripción SOX9/genética , Factor Nuclear Tiroideo 1/metabolismo , Factor Nuclear Tiroideo 1/genéticaRESUMEN
A synthetic method to prepare dispiroheterocycles containing two all-carbon quaternary centers efficiently that relies on the gold(I)-catalyzed double spirocyclization of 3-ene-1,7-diyne esters is described. The suggested mechanism delineates a rare example of a dispirocyclization featuring two 1,n-acyloxy shifts comprising a 1,3-acyloxy migration and an interrupted 1,5-acyl migration that was achieved with the assistance of residual water in the reaction media.
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A synthetic method for the efficient preparation of partially hydrogenated benzo[f]cyclobuta[cd]cyclopenta[h]benzofurans and cyclopropa[c]chromen-3a(1H)-ols that relies on the gold(I)-catalyzed cascade cycloisomerization of 3-allyloxy-1,6-diynes is described.
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Understanding the cellular processes that underlie early lung adenocarcinoma (LUAD) development is needed to devise intervention strategies1. Here we studied 246,102 single epithelial cells from 16 early-stage LUADs and 47 matched normal lung samples. Epithelial cells comprised diverse normal and cancer cell states, and diversity among cancer cells was strongly linked to LUAD-specific oncogenic drivers. KRAS mutant cancer cells showed distinct transcriptional features, reduced differentiation and low levels of aneuploidy. Non-malignant areas surrounding human LUAD samples were enriched with alveolar intermediate cells that displayed elevated KRT8 expression (termed KRT8+ alveolar intermediate cells (KACs) here), reduced differentiation, increased plasticity and driver KRAS mutations. Expression profiles of KACs were enriched in lung precancer cells and in LUAD cells and signified poor survival. In mice exposed to tobacco carcinogen, KACs emerged before lung tumours and persisted for months after cessation of carcinogen exposure. Moreover, they acquired Kras mutations and conveyed sensitivity to targeted KRAS inhibition in KAC-enriched organoids derived from alveolar type 2 (AT2) cells. Last, lineage-labelling of AT2 cells or KRT8+ cells following carcinogen exposure showed that KACs are possible intermediates in AT2-to-tumour cell transformation. This study provides new insights into epithelial cell states at the root of LUAD development, and such states could harbour potential targets for prevention or intervention.
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Adenocarcinoma del Pulmón , Diferenciación Celular , Células Epiteliales , Neoplasias Pulmonares , Animales , Humanos , Ratones , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/patología , Células Epiteliales Alveolares/metabolismo , Células Epiteliales Alveolares/patología , Aneuploidia , Carcinógenos/toxicidad , Células Epiteliales/clasificación , Células Epiteliales/metabolismo , Células Epiteliales/patología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Mutación , Organoides/efectos de los fármacos , Organoides/metabolismo , Lesiones Precancerosas/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Tasa de Supervivencia , Productos de Tabaco/efectos adversos , Productos de Tabaco/toxicidadRESUMEN
Cuproptosis is a newly identified form of cell death driven by copper. Recently, the role of copper and copper triggered cell death in the pathogenesis of cancers have attracted attentions. Cuproptosis has garnered enormous interest in cancer research communities because of its great potential for cancer therapy. Copper-based treatment exerts an inhibiting role in tumor growth and may open the door for the treatment of chemotherapy-insensitive tumors. In this review, we provide a critical analysis on copper homeostasis and the role of copper dysregulation in the development and progression of cancers. Then the core molecular mechanisms of cuproptosis and its role in cancer is discussed, followed by summarizing the current understanding of copper-based agents (copper chelators, copper ionophores, and copper complexes-based dynamic therapy) for cancer treatment. Additionally, we summarize the emerging data on copper complexes-based agents and copper ionophores to subdue tumor chemotherapy resistance in different types of cancers. We also review the small-molecule compounds and nanoparticles (NPs) that may kill cancer cells by inducing cuproptosis, which will shed new light on the development of anticancer drugs through inducing cuproptosis in the future. Finally, the important concepts and pressing questions of cuproptosis in future research that should be focused on were discussed. This review article suggests that targeting cuproptosis could be a novel antitumor therapy and treatment strategy to overcome cancer drug resistance.
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Cobre , Neoplasias , Humanos , Resistencia a Antineoplásicos/genética , Muerte Celular , Ionóforos , Neoplasias/tratamiento farmacológico , Neoplasias/genética , ApoptosisRESUMEN
Cell type-specific use of the same DNA blueprint generates diverse cell types. Such diversity must also be executed via differential deployment of the same subcellular machinery. However, our understanding of the size, distribution, and dynamics of subcellular machinery in native tissues and their connection to cellular diversity remains limited. We generate and characterize an inducible tricolor reporter mouse, dubbed "Kaleidoscope," for simultaneous imaging of lysosomes, mitochondria, and microtubules in any cell type and at a single-cell resolution. The expected subcellular compartments are labeled in culture and in tissues with no impact on cellular and organismal viability. Quantitative and live imaging of the tricolor reporter captures cell type-specific organelle features and kinetics in the lung, as well as their changes after Sendai virus infection. Yap/Taz mutant lung epithelial cells undergo accelerated lamellar body maturation, a subcellular manifestation of their molecular defects. A comprehensive toolbox of reporters for all subcellular structures is expected to transform our understanding of cell biology in tissues.
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Lisosomas , Microtúbulos , Mitocondrias , Animales , Ratones , Células Epiteliales/citología , CinéticaRESUMEN
Complex microbial ecosystems in both gastrointestinal and respiratory systems have been found to have a significant impact on human health. Growing evidence has demonstrated that intestinal dysbiosis can increase vulnerability to pulmonary infections. However, changes in the composition and activity of the intestinal flora after probiotic supplementation may alter the disease state of the host. The effects of probiotics on the improvement of diseases, such as severe pneumonia (SP), in intensive care units (ICUs) remain controversial. We retrospectively included 88 patients diagnosed with severe pneumonia between April 2021 and June 2022. The patients were divided into 2 groups: a probiotic group (nâ =â 40) and a control group (nâ =â 48). In addition, changes in CRP, PCT, WBC, IL-6, Clostridium difficile toxin, and PSI pneumonia scores were assessed. Changes in the gut microbiome of the patients were assessed using amplicon sequencing. Compared to the control group, a significant reduction in the incidence of length of hospital stay was observed in the probiotic group, but there were no significant differences in the mortality rate, duration of fever, diarrhea, and constipation. After probiotic treatment, CRP, PCT, WBC, and PSI score were significantly lower than before, and better clinical efficacy was achieved in the probiotic group for the duration of antibiotic therapy. Gut microbiota analysis revealed that the abundance of opportunistic pathogens (e.g., Massilia) increased remarkably at the genus level in the control group, and a significant increase in Erysipelotrichaceae_ge was observed after probiotic intervention. The control group showed an increase in opportunistic pathogens (Citrobacter, Massilia) during the antibiotic treatment. Probiotics interventions inhibit the growth of opportunistic pathogens. In addition, we found that the population of butyrate-producing bacteria (e.g., Ruminococcaceae UCG-005) increased following probiotic treatment.
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Microbioma Gastrointestinal , Neumonía , Probióticos , Humanos , Anciano , Ecosistema , Estudios Retrospectivos , Probióticos/uso terapéutico , Neumonía/tratamiento farmacológico , Resultado del Tratamiento , Antibacterianos/uso terapéuticoRESUMEN
Ferroptosis, a unique modality of cell death with mechanistic and morphological differences from other cell death modes, plays a pivotal role in regulating tumorigenesis and offers a new opportunity for modulating anticancer drug resistance. Aberrant epigenetic modifications and posttranslational modifications (PTMs) promote anticancer drug resistance, cancer progression, and metastasis. Accumulating studies indicate that epigenetic modifications can transcriptionally and translationally determine cancer cell vulnerability to ferroptosis and that ferroptosis functions as a driver in nervous system diseases (NSDs), cardiovascular diseases (CVDs), liver diseases, lung diseases, and kidney diseases. In this review, we first summarize the core molecular mechanisms of ferroptosis. Then, the roles of epigenetic processes, including histone PTMs, DNA methylation, and noncoding RNA regulation and PTMs, such as phosphorylation, ubiquitination, SUMOylation, acetylation, methylation, and ADP-ribosylation, are concisely discussed. The roles of epigenetic modifications and PTMs in ferroptosis regulation in the genesis of diseases, including cancers, NSD, CVDs, liver diseases, lung diseases, and kidney diseases, as well as the application of epigenetic and PTM modulators in the therapy of these diseases, are then discussed in detail. Elucidating the mechanisms of ferroptosis regulation mediated by epigenetic modifications and PTMs in cancer and other diseases will facilitate the development of promising combination therapeutic regimens containing epigenetic or PTM-targeting agents and ferroptosis inducers that can be used to overcome chemotherapeutic resistance in cancer and could be used to prevent other diseases. In addition, these mechanisms highlight potential therapeutic approaches to overcome chemoresistance in cancer or halt the genesis of other diseases.
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Antineoplásicos , Ferroptosis , Enfermedades Renales , Enfermedades Pulmonares , Neoplasias , Humanos , Ferroptosis/genética , Procesamiento Proteico-Postraduccional/genética , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Neoplasias/patología , Metilación de ADN , Epigénesis Genética/genética , Antineoplásicos/uso terapéutico , Enfermedades Pulmonares/tratamiento farmacológico , Enfermedades Pulmonares/genéticaRESUMEN
The Omicron variant of the severe acute respiratory syndrome coronavirus 2 (SARSCoV2) infected a substantial proportion of Chinese population, and understanding the factors underlying the severity of the disease and fatality is valuable for future prevention and clinical treatment. We recruited 64 patients with invasive ventilation for COVID-19 and performed metatranscriptomic sequencing to profile host transcriptomic profiles, plus viral, bacterial, and fungal content, as well as virulence factors and examined their relationships to 28-day mortality were examined. In addition, the bronchoalveolar lavage fluid (BALF) samples from invasive ventilated hospital/community-acquired pneumonia patients (HAP/CAP) sampled in 2019 were included for comparison. Genomic analysis revealed that all Omicron strains belong to BA.5 and BF.7 sub-lineages, with no difference in 28-day mortality between them. Compared to HAP/CAP cohort, invasive ventilated COVID-19 patients have distinct host transcriptomic and microbial signatures in the lower respiratory tract; and in the COVID-19 non-survivors, we found significantly lower gene expressions in pathways related viral processes and positive regulation of protein localization to plasma membrane, higher abundance of opportunistic pathogens including bacterial Alloprevotella, Caulobacter, Escherichia-Shigella, Ralstonia and fungal Aspergillus sydowii and Penicillium rubens. Correlational analysis further revealed significant associations between host immune responses and microbial compositions, besides synergy within viral, bacterial, and fungal pathogens. Our study presents the relationships of lower respiratory tract microbiome and transcriptome in invasive ventilated COVID-19 patients, providing the basis for future clinical treatment and reduction of fatality.
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COVID-19 , Microbiota , Neumonía , Humanos , COVID-19/genética , COVID-19/metabolismo , SARS-CoV-2/genética , Respiración Artificial , Pulmón , Neumonía/metabolismo , BacteriasRESUMEN
All-inorganic CsPbI3 perovskite quantum dots (QDs) have received extensive attention in developing optoelectronic devices due to their outstanding properties. Here, using time-dependent density functional theory (TDDFT), the optical properties of the three distinct phases (α, γ, and δ) of the CsPbI3 QDs are investigated. Surprisingly, the δ phase structured QDs exhibit stronger optical absorption properties than the α and γ phase QDs when exposed to equivalent laser irradiation. Considering the quantum size effect, size regulation is also performed on the three structures, the results reveal a significant improvement in optical properties as the size increases in the direction of laser irradiation. More interestingly, Ag-hybrid QDs show better optical gain and maintain a laser-driven metallic state. Our results demonstrate the great potential of size adjustment and metal nanowire coupling in improving the optoelectronic properties of QDs and developing efficient photovoltaic devices.
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Cell plasticity theoretically extends to all possible cell types, but naturally decreases as cells differentiate, whereas injury-repair re-engages the developmental plasticity. Here we show that the lung alveolar type 2 (AT2)-specific transcription factor (TF), CEBPA, restricts AT2 cell plasticity in the mouse lung. AT2 cells undergo transcriptional and epigenetic maturation postnatally. Without CEBPA, both neonatal and mature AT2 cells reduce the AT2 program, but only the former reactivate the SOX9 progenitor program. Sendai virus infection bestows mature AT2 cells with neonatal plasticity where Cebpa mutant, but not wild type, AT2 cells express SOX9, as well as more readily proliferate and form KRT8/CLDN4+ transitional cells. CEBPA promotes the AT2 program by recruiting the lung lineage TF NKX2-1. The temporal change in CEBPA-dependent plasticity reflects AT2 cell developmental history. The ontogeny of AT2 cell plasticity and its transcriptional and epigenetic mechanisms have implications in lung regeneration and cancer.
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Pneumonia is a worldwide threat, making discovery of novel means to combat lower respiratory tract infection an urgent need. Manipulating the lungs' intrinsic host defenses by therapeutic delivery of certain pathogen-associated molecular patterns protects mice against pneumonia in a reactive oxygen species (ROS)-dependent manner. Here we show that antimicrobial ROS are induced from lung epithelial cells by interactions of CpG oligodeoxynucleotides (ODN) with mitochondrial voltage-dependent anion channel 1 (VDAC1). The ODN-VDAC1 interaction alters cellular ATP/ADP/AMP localization, increases delivery of electrons to the electron transport chain (ETC), increases mitochondrial membrane potential (ΔΨm), differentially modulates ETC complex activities and consequently results in leak of electrons from ETC complex III and superoxide formation. The ODN-induced mitochondrial ROS yield protective antibacterial effects. Together, these studies identify a therapeutic metabolic manipulation strategy to broadly protect against pneumonia without reliance on antibiotics.
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Antiinfecciosos , Neumonía , Ratones , Animales , Especies Reactivas de Oxígeno/metabolismo , Mitocondrias/metabolismo , Pulmón/metabolismo , Neumonía/metabolismo , Antiinfecciosos/farmacología , Potencial de la Membrana MitocondrialRESUMEN
Divergent N6-methyladenosine (m6A) modifications are dynamic and reversible posttranscriptional RNA modifications that are mediated by m6A regulators or m6A RNA methylation regulators, i.e., methyltransferases ("writers"), demethylases ("erasers"), and m6A-binding proteins ("readers"). Aberrant m6A modifications are associated with cancer occurrence, development, progression, and prognosis. Numerous studies have established that aberrant m6A regulators function as either tumor suppressors or oncogenes in multiple tumor types. However, the functions and mechanisms of m6A regulators in cancer remain largely elusive and should be explored. Emerging studies suggest that m6A regulators can be modulated by epigenetic modifications, namely, ubiquitination, SUMOylation, acetylation, methylation, phosphorylation, O-GlcNAcylation, ISGylation, and lactylation or via noncoding RNA action, in cancer. This review summarizes the current roles of m6A regulators in cancer. The roles and mechanisms for epigenetic modification of m6A regulators in cancer genesis are segregated. The review will improve the understanding of the epigenetic regulatory mechanisms of m6A regulators.