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1.
Cell ; 184(9): 2362-2371.e9, 2021 04 29.
Artículo en Inglés | MEDLINE | ID: mdl-33735608

RESUMEN

The 501Y.V2 variants of SARS-CoV-2 containing multiple mutations in spike are now dominant in South Africa and are rapidly spreading to other countries. Here, experiments with 18 pseudotyped viruses showed that the 501Y.V2 variants do not confer increased infectivity in multiple cell types except for murine ACE2-overexpressing cells, where a substantial increase in infectivity was observed. Notably, the susceptibility of the 501Y.V2 variants to 12 of 17 neutralizing monoclonal antibodies was substantially diminished, and the neutralization ability of the sera from convalescent patients and immunized mice was also reduced for these variants. The neutralization resistance was mainly caused by E484K and N501Y mutations in the receptor-binding domain of spike. The enhanced infectivity in murine ACE2-overexpressing cells suggests the possibility of spillover of the 501Y.V2 variants to mice. Moreover, the neutralization resistance we detected for the 501Y.V2 variants suggests the potential for compromised efficacy of monoclonal antibodies and vaccines.


Asunto(s)
COVID-19/inmunología , COVID-19/virología , Evasión Inmune , SARS-CoV-2/patogenicidad , Enzima Convertidora de Angiotensina 2/metabolismo , Anticuerpos Monoclonales/inmunología , Anticuerpos Neutralizantes/inmunología , Antígenos Virales/inmunología , Línea Celular Tumoral , Células HEK293 , Humanos , Mutación/genética , SARS-CoV-2/genética
2.
Cell ; 182(5): 1284-1294.e9, 2020 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-32730807

RESUMEN

The spike protein of SARS-CoV-2 has been undergoing mutations and is highly glycosylated. It is critically important to investigate the biological significance of these mutations. Here, we investigated 80 variants and 26 glycosylation site modifications for the infectivity and reactivity to a panel of neutralizing antibodies and sera from convalescent patients. D614G, along with several variants containing both D614G and another amino acid change, were significantly more infectious. Most variants with amino acid change at receptor binding domain were less infectious, but variants including A475V, L452R, V483A, and F490L became resistant to some neutralizing antibodies. Moreover, the majority of glycosylation deletions were less infectious, whereas deletion of both N331 and N343 glycosylation drastically reduced infectivity, revealing the importance of glycosylation for viral infectivity. Interestingly, N234Q was markedly resistant to neutralizing antibodies, whereas N165Q became more sensitive. These findings could be of value in the development of vaccine and therapeutic antibodies.


Asunto(s)
Antígenos Virales/genética , Betacoronavirus/patogenicidad , Mutación , Glicoproteína de la Espiga del Coronavirus/genética , Células A549 , Animales , Antígenos Virales/inmunología , Betacoronavirus/genética , Betacoronavirus/inmunología , Sitios de Unión , Bovinos , Chlorocebus aethiops , Cricetinae , Perros , Glicosilación , Células HEK293 , Células HeLa , Humanos , Macaca mulatta , Células de Riñón Canino Madin Darby , Ratones , Células RAW 264.7 , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/inmunología , Glicoproteína de la Espiga del Coronavirus/metabolismo , Porcinos , Células Vero , Virulencia/genética
3.
Nat Immunol ; 23(10): 1433-1444, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36138184

RESUMEN

Naive T cells undergo radical changes during the transition from dormant to hyperactive states upon activation, which necessitates de novo protein production via transcription and translation. However, the mechanism whereby T cells globally promote translation remains largely unknown. Here, we show that on exit from quiescence, T cells upregulate transfer RNA (tRNA) m1A58 'writer' proteins TRMT61A and TRMT6, which confer m1A58 RNA modification on a specific subset of early expressed tRNAs. These m1A-modified early tRNAs enhance translation efficiency, enabling rapid and necessary synthesis of MYC and of a specific group of key functional proteins. The MYC protein then guides the exit of naive T cells from a quiescent state into a proliferative state and promotes rapid T cell expansion after activation. Conditional deletion of the Trmt61a gene in mouse CD4+ T cells causes MYC protein deficiency and cell cycle arrest, disrupts T cell expansion upon cognate antigen stimulation and alleviates colitis in a mouse adoptive transfer colitis model. Our study elucidates for the first time, to our knowledge, the in vivo physiological roles of tRNA-m1A58 modification in T cell-mediated pathogenesis and reveals a new mechanism of tRNA-m1A58-controlled T cell homeostasis and signal-dependent translational control of specific key proteins.


Asunto(s)
Colitis , ARN de Transferencia , Traslado Adoptivo , Animales , Proliferación Celular/genética , Colitis/genética , Ratones , Biosíntesis de Proteínas , ARN de Transferencia/genética , ARN de Transferencia/metabolismo , Linfocitos T/metabolismo
4.
Mol Cell ; 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-39002544

RESUMEN

5-methylcytosine (m5C) is a prevalent RNA modification crucial for gene expression regulation. However, accurate and sensitive m5C sites identification remains challenging due to severe RNA degradation and reduced sequence complexity during bisulfite sequencing (BS-seq). Here, we report m5C-TAC-seq, a bisulfite-free approach combining TET-assisted m5C-to-f5C oxidation with selective chemical labeling, therefore enabling direct base-resolution m5C detection through pre-enrichment and C-to-T transitions at m5C sites. With m5C-TAC-seq, we comprehensively profiled the m5C methylomes in human and mouse cells, identifying a substantially larger number of confident m5C sites. Through perturbing potential m5C methyltransferases, we deciphered the responsible enzymes for most m5C sites, including the characterization of NSUN5's involvement in mRNA m5C deposition. Additionally, we characterized m5C dynamics during mESC differentiation. Notably, the mild reaction conditions and preservation of nucleotide composition in m5C-TAC-seq allow m5C detection in chromatin-associated RNAs. The accurate and robust m5C-TAC-seq will advance research into m5C methylation functional investigation.

5.
Cell ; 150(3): 575-89, 2012 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-22863010

RESUMEN

The mechanism by which cells decide to skip mitosis to become polyploid is largely undefined. Here we used a high-content image-based screen to identify small-molecule probes that induce polyploidization of megakaryocytic leukemia cells and serve as perturbagens to help understand this process. Our study implicates five networks of kinases that regulate the switch to polyploidy. Moreover, we find that dimethylfasudil (diMF, H-1152P) selectively increased polyploidization, mature cell-surface marker expression, and apoptosis of malignant megakaryocytes. An integrated target identification approach employing proteomic and shRNA screening revealed that a major target of diMF is Aurora kinase A (AURKA). We further find that MLN8237 (Alisertib), a selective inhibitor of AURKA, induced polyploidization and expression of mature megakaryocyte markers in acute megakaryocytic leukemia (AMKL) blasts and displayed potent anti-AMKL activity in vivo. Our findings provide a rationale to support clinical trials of MLN8237 and other inducers of polyploidization and differentiation in AMKL.


Asunto(s)
Azepinas/farmacología , Descubrimiento de Drogas , Leucemia Megacarioblástica Aguda/tratamiento farmacológico , Megacariocitos/metabolismo , Poliploidía , Pirimidinas/farmacología , Bibliotecas de Moléculas Pequeñas , 1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/análogos & derivados , 1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/farmacología , Animales , Aurora Quinasa A , Aurora Quinasas , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Humanos , Leucemia Megacarioblástica Aguda/genética , Megacariocitos/citología , Megacariocitos/patología , Ratones , Ratones Endogámicos C57BL , Mapas de Interacción de Proteínas , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/metabolismo , Quinasas Asociadas a rho/metabolismo
6.
Nature ; 591(7848): 147-151, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33505025

RESUMEN

Many sequence variants have been linked to complex human traits and diseases1, but deciphering their biological functions remains challenging, as most of them reside in noncoding DNA. Here we have systematically assessed the binding of 270 human transcription factors to 95,886 noncoding variants in the human genome using an ultra-high-throughput multiplex protein-DNA binding assay, termed single-nucleotide polymorphism evaluation by systematic evolution of ligands by exponential enrichment (SNP-SELEX). The resulting 828 million measurements of transcription factor-DNA interactions enable estimation of the relative affinity of these transcription factors to each variant in vitro and evaluation of the current methods to predict the effects of noncoding variants on transcription factor binding. We show that the position weight matrices of most transcription factors lack sufficient predictive power, whereas the support vector machine combined with the gapped k-mer representation show much improved performance, when assessed on results from independent SNP-SELEX experiments involving a new set of 61,020 sequence variants. We report highly predictive models for 94 human transcription factors and demonstrate their utility in genome-wide association studies and understanding of the molecular pathways involved in diverse human traits and diseases.


Asunto(s)
Polimorfismo de Nucleótido Simple/genética , Técnica SELEX de Producción de Aptámeros , Máquina de Vectores de Soporte , Factores de Transcripción/metabolismo , Sitios de Unión/genética , Enfermedad/genética , Genoma Humano/genética , Humanos , Ligandos , Unión Proteica
7.
Circ Res ; 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39056179

RESUMEN

BACKGROUND: Macrophages are key players in obesity-associated cardiovascular diseases, which are marked by inflammatory and immune alterations. However, the pathophysiological mechanisms underlying macrophage's role in obesity-induced cardiac inflammation are incompletely understood. Our study aimed to identify the key macrophage population involved in obesity-induced cardiac dysfunction and investigate the molecular mechanism that contributes to the inflammatory response. METHODS AND RESULTS: Though analyzing in-depth cardiac macrophage clusters identified by single macrophage RNA-sequencing, we find that the Ccr2 cluster undergoes a functional transition from homeostatic maintenance to proinflammation. Our data highlight specific changes in macrophage behavior during cardiac dysfunction under metabolic challenge. Consistently, inducible ablation of CCR2+CX3CR1+ macrophages by a dual recombinase-based lineage-tracing approach or selective deletion of macrophage C-C chemokine receptor 2 (CCR2) prevents obesity-induced cardiac dysfunction. At the mechanistic level, we demonstrate that the obesity-induced functional shift of CCR2-expressing macrophages is mediated by the CCR2/ATF3/lysozyme 1/NF-κB (nuclear factor kappa B) signaling. Finally, we uncover a noncanonical role for lysozyme 1 as a transcription activator, binding to the RelA promoter, driving NF-κB signaling, and strongly promoting inflammation and cardiac dysfunction in obesity. CONCLUSIONS: Our findings suggest that lysozyme 1 may represent a potential target for the diagnosis of obesity-induced inflammation and the treatment of obesity-induced heart disease.

8.
J Virol ; 98(7): e0046724, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-38864621

RESUMEN

Acinetobacter baumannii, an opportunistic pathogen, poses a significant threat in intensive care units, leading to severe nosocomial infections. The rise of multi-drug-resistant strains, particularly carbapenem-resistant A. baumannii, has created formidable challenges for effective treatment. Given the prolonged development cycle and high costs associated with antibiotics, phages have garnered clinical attention as an alternative for combating infections caused by drug-resistant bacteria. However, the utilization of phage therapy encounters notable challenges, including the narrow host spectrum, where each phage targets a limited subset of bacteria, increasing the risk of phage resistance development. Additionally, uncertainties in immune system dynamics during treatment hinder tailoring symptomatic interventions based on patient-specific states. In this study, we isolated two A. baumannii phages from wastewater and conducted a comprehensive assessment of their potential applications. This evaluation included sequencing analysis, genome classification, pH and temperature stability assessments, and in vitro bacterial inhibition assays. Further investigations involved analyzing histological and cytokine alterations in rats undergoing phage cocktail treatment for pneumonia. The therapeutic efficacy of the phages was validated, and transcriptomic studies of rat lung tissue during phage treatment revealed crucial changes in the immune system. The findings from our study underscore the potential of phages for future development as a treatment strategy and offer compelling evidence regarding immune system dynamics throughout the treatment process.IMPORTANCEDue to the growing problem of multi-drug-resistant bacteria, the use of phages is being considered as an alternative to antibiotics, and the genetic safety and application stability of phages determine the potential of phage application. The absence of drug resistance genes and virulence genes in the phage genome can ensure the safety of phage application, and the fact that phage can remain active in a wide range of temperatures and pH is also necessary for application. In addition, the effect evaluation of preclinical studies is especially important for clinical application. By simulating the immune response situation during the treatment process through mammalian models, the changes in animal immunity can be observed, and the effect of phage therapy can be further evaluated. Our study provides compelling evidence that phages hold promise for further development as therapeutic agents for Acinetobacter baumannii infections.


Asunto(s)
Infecciones por Acinetobacter , Acinetobacter baumannii , Bacteriófagos , Carbapenémicos , Modelos Animales de Enfermedad , Terapia de Fagos , Acinetobacter baumannii/virología , Acinetobacter baumannii/efectos de los fármacos , Animales , Infecciones por Acinetobacter/terapia , Infecciones por Acinetobacter/microbiología , Ratas , Terapia de Fagos/métodos , Carbapenémicos/farmacología , Bacteriófagos/fisiología , Bacteriófagos/genética , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Farmacorresistencia Bacteriana Múltiple , Masculino , Genoma Viral , Aguas Residuales , Neumonía/terapia , Neumonía/microbiología , Neumonía/virología
9.
EMBO Rep ; 24(9): e56512, 2023 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-37437058

RESUMEN

Long interspersed element 1 (LINE-1) is the only active autonomous mobile element in the human genome. Its transposition can exert deleterious effects on the structure and function of the host genome and cause sporadic genetic diseases. Tight control of LINE-1 mobilization by the host is crucial for genetic stability. In this study, we report that MOV10 recruits the main decapping enzyme DCP2 to LINE-1 RNA and forms a complex of MOV10, DCP2, and LINE-1 RNP, exhibiting liquid-liquid phase separation (LLPS) properties. DCP2 cooperates with MOV10 to decap LINE-1 RNA, which causes degradation of LINE-1 RNA and thus reduces LINE-1 retrotransposition. We here identify DCP2 as one of the key effector proteins determining LINE-1 replication, and elucidate an LLPS mechanism that facilitates the anti-LINE-1 action of MOV10 and DCP2.


Asunto(s)
Gránulos Citoplasmáticos , ARN Helicasas , Humanos , Gránulos Citoplasmáticos/metabolismo , Endorribonucleasas/genética , Elementos de Nucleótido Esparcido Largo , ARN/metabolismo , ARN Helicasas/metabolismo
10.
Exp Cell Res ; 437(1): 113998, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38513962

RESUMEN

Plasma saturated free fatty acid (FFA)-induced endothelial dysfunction (ED) contributes to the pathogenesis of atherosclerosis and cardiovascular diseases. However, the mechanism underlying saturated FFA-induced ED remains unclear. This study demonstrated that palmitic acid (PA) induced ED by activating the NADPH oxidase (NOX)/ROS signaling pathway to activate protein phosphatase 4 (PP4) and protein phosphatase 2A (PP2A), thereby reducing endothelial nitric oxide synthase (eNOS) phosphorylation at Ser633 and Ser1177, respectively. Okadaic acid (OA) and fostriecin (FST), which are inhibitors of PP2A, inhibited the PA-induced decreases in eNOS phosphorylation at Ser633 and Ser1177. The antioxidants N-acetylcysteine (NAC) and apocynin (APO) or knockdown of gp91phox or p67phox (NOX subunits) restored PA-mediated downregulation of PP4R2 protein expression and eNOS Ser633 phosphorylation. Knockdown of the PP4 catalytic subunit (PP4c) specifically increased eNOS Ser633 phosphorylation, while silencing the PP2A catalytic subunit (PP2Ac) restored only eNOS Ser1177 phosphorylation. Furthermore, PA dramatically decreased the protein expression of the PP4 regulatory subunit R2 (PP4R2) but not the other regulatory subunits. PP4R2 overexpression increased eNOS Ser633 phosphorylation, nitric oxide (NO) production, cell migration and tube formation but did not change eNOS Ser1177 phosphorylation levels. Coimmunoprecipitation (Co-IP) suggested that PP4R2 and PP4c interacted with the PP4R3α and eNOS proteins. In summary, PA decreases PP4R2 protein expression through the Nox/ROS pathway to activate PP4, which contributes to ED by dephosphorylating eNOS at Ser633. The results of this study suggest that PP4 is a novel therapeutic target for ED and ED-associated vascular diseases.


Asunto(s)
Óxido Nítrico Sintasa de Tipo III , Fosfoproteínas Fosfatasas , Enfermedades Vasculares , Humanos , Fosforilación , Óxido Nítrico Sintasa de Tipo III/metabolismo , Ácido Palmítico/farmacología , Serina/metabolismo , Especies Reactivas de Oxígeno , Células Cultivadas , Proteína Fosfatasa 2/metabolismo , Óxido Nítrico/metabolismo
11.
Mol Ther ; 32(7): 2340-2356, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38715363

RESUMEN

Human papillomavirus (HPV) 16 and 18 infections are related to many human cancers. Despite several preventive vaccines for high-risk (hr) HPVs, there is still an urgent need to develop therapeutic HPV vaccines for targeting pre-existing hrHPV infections and lesions. In this study, we developed a lipid nanoparticle (LNP)-formulated mRNA-based HPV therapeutic vaccine (mHTV)-03E2, simultaneously targeting the E2/E6/E7 of both HPV16 and HPV18. mHTV-03E2 dramatically induced antigen-specific cellular immune responses, leading to significant CD8+ T cell infiltration and cytotoxicity in TC-1 tumors derived from primary lung epithelial cells of C57BL/6 mice expressing HPV E6/E7 antigens, mediated significant tumor regression, and prolonged animal survival, in a dose-dependent manner. We further demonstrated significant T cell immunity against HPV16/18 E6/E7 antigens for up to 4 months post-vaccination in immunological and distant tumor rechallenging experiments, suggesting robust memory T cell immunity against relapse. Finally, mHTV-03E2 synergized with immune checkpoint blockade to inhibit tumor growth and extend animal survival, indicating the potential in combination therapy. We conclude that mHTV-03E2 is an excellent candidate therapeutic mRNA vaccine for treating malignancies caused by HPV16 or HPV18 infections.


Asunto(s)
Proteínas Oncogénicas Virales , Infecciones por Papillomavirus , Vacunas contra Papillomavirus , ARN Mensajero , Animales , Ratones , Vacunas contra Papillomavirus/inmunología , Humanos , Infecciones por Papillomavirus/inmunología , Infecciones por Papillomavirus/virología , Infecciones por Papillomavirus/terapia , Infecciones por Papillomavirus/prevención & control , Femenino , Proteínas Oncogénicas Virales/inmunología , Proteínas Oncogénicas Virales/genética , ARN Mensajero/genética , ARN Mensajero/inmunología , Nanopartículas/química , Papillomavirus Humano 16/inmunología , Papillomavirus Humano 16/genética , Ratones Endogámicos C57BL , Papillomavirus Humano 18/inmunología , Papillomavirus Humano 18/genética , Proteínas E7 de Papillomavirus/inmunología , Proteínas E7 de Papillomavirus/genética , Vacunas contra el Cáncer/inmunología , Vacunas contra el Cáncer/administración & dosificación , Línea Celular Tumoral , Modelos Animales de Enfermedad , Linfocitos T CD8-positivos/inmunología , Proteínas Represoras/inmunología , Proteínas Represoras/genética , Proteínas de Unión al ADN , Liposomas
12.
Mol Cell ; 68(5): 993-1005.e9, 2017 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-29107537

RESUMEN

Gene expression can be post-transcriptionally regulated via dynamic and reversible RNA modifications. N1-methyladenosine (m1A) is a recently identified mRNA modification; however, little is known about its precise location and biogenesis. Here, we develop a base-resolution m1A profiling method, based on m1A-induced misincorporation during reverse transcription, and report distinct classes of m1A methylome in the human transcriptome. m1A in 5' UTR, particularly those at the mRNA cap, associate with increased translation efficiency. A different, small subset of m1A exhibit a GUUCRA tRNA-like motif, are evenly distributed in the transcriptome, and are dependent on the methyltransferase TRMT6/61A. Additionally, we show that m1A is prevalent in the mitochondrial-encoded transcripts. Manipulation of m1A level via TRMT61B, a mitochondria-localizing m1A methyltransferase, demonstrates that m1A in mitochondrial mRNA interferes with translation. Collectively, our approaches reveal distinct classes of m1A methylome and provide a resource for functional studies of m1A-mediated epitranscriptomic regulation.


Asunto(s)
Adenosina/análogos & derivados , Núcleo Celular/metabolismo , Mitocondrias/metabolismo , Procesamiento Postranscripcional del ARN , ARN Mensajero/metabolismo , ARN de Transferencia/metabolismo , Imagen Individual de Molécula/métodos , Regiones no Traducidas 5' , Adenosina/metabolismo , Células HEK293 , Humanos , Proteínas Mitocondriales/biosíntesis , Proteínas Mitocondriales/genética , Proteínas Nucleares/biosíntesis , Proteínas Nucleares/genética , Biosíntesis de Proteínas , Caperuzas de ARN , Interferencia de ARN , ARN Mensajero/genética , ARN de Transferencia/genética , Transfección , ARNt Metiltransferasas/genética , ARNt Metiltransferasas/metabolismo
13.
Chem Soc Rev ; 53(10): 5014-5053, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38600823

RESUMEN

Alumina materials, as one of the cornerstones of the modern chemical industry, possess physical and chemical properties that include excellent mechanical strength and structure stability, which also make them highly suitable as catalyst supports. Alumina-supported Pd-based catalysts with the advantages of exceptional catalytic performance, flexible regulated surface metal/acid sites, and good regeneration ability have been widely used in many traditional chemical industry fields and have also shown great application prospects in emerging fields. This review aims to provide an overview of the recent advances in alumina and its supported Pd-based catalysts. Specifically, the synthesis strategies, morphology transformation mechanisms, and structural properties of alumina with various morphologies are comprehensively summarized and discussed in-depth. Then, the preparation approaches of Pd/Al2O3 catalysts (impregnation, precipitation, and other emerging methods), as well as the metal-support interactions (MSIs), are revisited. Moreover, Some promising applications have been chosen as representative reactions in fine chemicals, environmental purification, and sustainable development fields to highlight the universal functionality of the alumina-supported Pd-based catalysts. The role of the Pd species, alumina support, promoters, and metal-support interactions in the enhancement of catalytic performance are also discussed. Finally, some challenges and upcoming opportunities in the academic and industrial application of the alumina and its supported Pd-based are presented and put forward.

14.
Mol Cancer ; 23(1): 123, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38849845

RESUMEN

BACKGROUND: Pediatric-type diffuse high-grade glioma (pHGG) is the most frequent malignant brain tumor in children and can be subclassified into multiple entities. Fusion genes activating the MET receptor tyrosine kinase often occur in infant-type hemispheric glioma (IHG) but also in other pHGG and are associated with devastating morbidity and mortality. METHODS: To identify new treatment options, we established and characterized two novel orthotopic mouse models harboring distinct MET fusions. These included an immunocompetent, murine allograft model and patient-derived orthotopic xenografts (PDOX) from a MET-fusion IHG patient who failed conventional therapy and targeted therapy with cabozantinib. With these models, we analyzed the efficacy and pharmacokinetic properties of three MET inhibitors, capmatinib, crizotinib and cabozantinib, alone or combined with radiotherapy. RESULTS: Capmatinib showed superior brain pharmacokinetic properties and greater in vitro and in vivo efficacy than cabozantinib or crizotinib in both models. The PDOX models recapitulated the poor efficacy of cabozantinib experienced by the patient. In contrast, capmatinib extended survival and induced long-term progression-free survival when combined with radiotherapy in two complementary mouse models. Capmatinib treatment increased radiation-induced DNA double-strand breaks and delayed their repair. CONCLUSIONS: We comprehensively investigated the combination of MET inhibition and radiotherapy as a novel treatment option for MET-driven pHGG. Our seminal preclinical data package includes pharmacokinetic characterization, recapitulation of clinical outcomes, coinciding results from multiple complementing in vivo studies, and insights into molecular mechanism underlying increased efficacy. Taken together, we demonstrate the groundbreaking efficacy of capmatinib and radiation as a highly promising concept for future clinical trials.


Asunto(s)
Neoplasias Encefálicas , Glioma , Proteínas Proto-Oncogénicas c-met , Ensayos Antitumor por Modelo de Xenoinjerto , Animales , Humanos , Glioma/patología , Glioma/tratamiento farmacológico , Glioma/genética , Glioma/terapia , Proteínas Proto-Oncogénicas c-met/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-met/genética , Proteínas Proto-Oncogénicas c-met/metabolismo , Ratones , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/radioterapia , Benzamidas/farmacología , Benzamidas/uso terapéutico , Línea Celular Tumoral , Proteínas de Fusión Oncogénica/genética , Proteínas de Fusión Oncogénica/metabolismo , Femenino , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Piridinas/farmacología , Piridinas/uso terapéutico , Crizotinib/farmacología , Crizotinib/uso terapéutico , Modelos Animales de Enfermedad , Niño , Clasificación del Tumor , Anilidas/farmacología , Imidazoles , Triazinas
15.
Apoptosis ; 29(3-4): 289-302, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38095762

RESUMEN

Metal ions play an important role in living organisms and are involved in essential physiological activities. However, the overload state of ions can cause excess free radicals, cell damage, and even cell death. Ferroptosis and cuproptosis are specific forms of cell death that are distinct from apoptosis, necroptosis, and other regulated cell death. These unique modalities of cell death, dependent on iron and copper, are regulated by multiple cellular metabolic pathways, including steady-state metal redox treatment mitochondrial activity of lipid, amino acid and glucose metabolism, and various signaling pathways associated with disease. Although the mechanisms of ferroptosis and cuproptosis are not yet fully understood, there is no doubt that ion overload plays a crucial act in these metal-dependent cell deaths. In this review, we discussed the core roles of ion overload in ferroptosis and cuproptosis, the association between metabolism imbalance and ferroptosis and cuproptosis, the extract the diseases caused by ion overload and current treatment modalities.


Asunto(s)
Ferroptosis , Enfermedades Renales , Muerte Celular Regulada , Humanos , Ferroptosis/genética , Apoptosis , Iones
16.
Apoptosis ; 29(1-2): 169-190, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37713112

RESUMEN

Cuprotosis, an emerging mode of cell death, has recently caught the attention of researchers worldwide. However, its impact on low-grade glioma (LGG) patients has not been fully explored. To gain a deeper insight into the relationship between cuprotosis and LGG patients' prognosis, we conducted this study in which LGG patients were divided into two clusters based on the expression of 18 cuprotosis-related genes. We found that LGG patients in cluster A had better prognosis than those in cluster B. The two clusters also differed in terms of immune cell infiltration and biological functions. Moreover, we identified differentially expressed genes (DEGs) between the two clusters and developed a cuprotosis-related prognostic signature through the least absolute shrinkage and selection operator (LASSO) analysis in the TCGA training cohort. This signature divided LGG patients into high- and low-risk groups, with the high-risk group having significantly shorter overall survival (OS) time than the low-risk group. Its predictive reliability for prognosis in LGG patients was confirmed by the TCGA internal validation cohort, CGGA325 cohort and CGGA693 cohort. Additionally, a nomogram was used to predict the 1-, 3-, and 5-year OS rates of each patient. The analysis of immune checkpoints and tumor mutation burden (TMB) has revealed that individuals belonging to high-risk groups have a greater chance of benefiting from immunotherapy. Functional experiments confirmed that interfering with the signature gene TNFRSF11B inhibited LGG cell proliferation and migration. Overall, this study shed light on the importance of cuprotosis in LGG patient prognosis. The cuprotosis-related prognostic signature is a reliable predictor for patient outcomes and immunotherapeutic response and can help to develop new therapies for LGG.


Asunto(s)
Apoptosis , Glioma , Humanos , Reproducibilidad de los Resultados , Muerte Celular , Glioma/genética , Glioma/terapia , Inmunoterapia
17.
Anal Chem ; 96(1): 309-316, 2024 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-38108827

RESUMEN

The separation and analysis of circulating tumor cells (CTCs) in liquid biopsy significantly facilitated clinical cancer diagnosis and personalized therapy. However, current methods face challenges in simultaneous efficient capturing, separation, and imaging of CTCs, and most of the devices cannot be reused/regenerated. We present here an innovative glowing octopus-inspired nanomachine (GOIN), capable of capturing, imaging, separating, and controlling the release of cancer cells from whole blood and normal cells. The GOIN comprises an aptamer-decorated magnetic fluorescent covalent organic framework (COF), which exhibits a strong affinity for nucleolin-overexpressed cancer cells through a multivalent binding effect. The captured cancer cells can be directly imaged using the intrinsic stable fluorescence of the COF layer in the GOIN. Employing magnet and NIR laser assistance enables easy separation and mild photothermal release of CTCs from the normal cells and the nanomachine without compromising cell viability. Moreover, the GOIN demonstrates a reusing capability, as the NIR-triggered CTC release is mild and nondestructive, allowing the GOIN to be reused at least three times.


Asunto(s)
Células Neoplásicas Circulantes , Humanos , Separación Celular/métodos , Células Neoplásicas Circulantes/patología , Línea Celular Tumoral , Diagnóstico por Imagen , Supervivencia Celular
18.
Anal Chem ; 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39012837

RESUMEN

Two-photon fluorescence lifetime microscopy (TP-FLIM) is a powerful quantitative imaging technique that characterizes and analyzes the structure and function of biological samples through a combination of intensity and lifetime imaging. Because TP-FLIM is independent of the fluorescence signal intensity and the fluorophore concentration, it is widely used in high-throughput, high-content drug screening and clinical diagnostics. Second harmonic generation (SHG) imaging technology has the advantages of high spatial resolution and imaging depth inherent to nonlinear optical imaging. Second harmonics often appear in noncentrosymmetric structures. Collagen tissue in biological organisms is a good example of these structures, showing strong harmonic effects. Therefore, SHG has been widely used for imaging of specific tissue structure imaging. TP-FLIM technology is highly sensitive for quantitatively detecting changes in microenvironments. The objective of this study is to examine pathological pulmonary fibrosis slices using a combined approach of TP-FLIM and SHG technology. The fluorescence lifetime data of pulmonary collagen fibers are analyzed by using phasor plot analysis methods, and normal collagen fibers and fibrotic collagen fibers are distinguished by calculating the aspect ratio from the SHG images formed by the collagen fibers. Our study provides a new method for a deeper understanding of the pathological mechanisms and clinical diagnosis of pulmonary fibrosis and other collagen fiber-related disorders.

19.
BMC Med ; 22(1): 54, 2024 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-38317131

RESUMEN

BACKGROUND: The appropriateness of hypertension thresholds for triggering action to prevent cardiovascular and renal complications among non-White populations in the UK is subject to question. Our objective was to establish ethnicity-specific systolic blood pressure (SBP) cutoffs for ethnic minority populations and assess the efficacy of these ethnicity-specific cutoffs in predicting adverse outcomes. METHODS: We analyzed data from UK Biobank, which included 444,418 participants from White, South Asian, Black Caribbean, and Black African populations with no history of cardiorenal complications. We fitted Poisson regression models with continuous SBP and ethnic groups, using Whites as the referent category, for the composite outcome of atherosclerotic cardiovascular disease, heart failure, and chronic kidney disease. We determined ethnicity-specific thresholds equivalent to the risks observed in Whites at SBP levels of 120, 130, and 140 mm Hg. We adjusted models for clinical characteristics, sociodemographic factors, and behavioral factors. The performance of ethnicity-specific thresholds for predicting adverse outcomes and associated population-attributable fraction (PAF) was assessed in ethnic minority groups. RESULTS: After a median follow-up of 12.5 years (interquartile range, 11.7-13.2), 32,662 (7.4%) participants had incident composite outcomes. At any given SBP, the predicted incidence rate of the composite outcome was the highest for South Asians, followed by White, Black Caribbean, and Black African. For an equivalent risk of outcomes observed in the White population at an SBP level of 140 mm Hg, the SBP threshold was lower for South Asians (123 mm Hg) and higher for Black Caribbean (156 mm Hg) and Black African (165 mm Hg). Furthermore, hypertension defined by ethnicity-specific thresholds was a stronger predictor and resulted in a larger PAF for composite outcomes in South Asians (21.5% [95% CI, 2.4,36.9] vs. 11.3% [95% CI, 2.6,19.1]) and Black Africans (7.1% [95% CI, 0.2,14.0] vs. 5.7 [95% CI, -16.2,23.5]) compared to hypertension defined by guideline-recommended thresholds. CONCLUSIONS: Guideline-recommended blood pressure thresholds may overestimate risks for the Black population and underestimate risks for South Asians. Using ethnicity-specific SBP thresholds may improve risk estimation and optimize hypertension management toward the goal of eliminating ethnic disparities in cardiorenal complications.


Asunto(s)
Etnicidad , Hipertensión , Humanos , Estudios Prospectivos , Presión Sanguínea , Biobanco del Reino Unido , Bancos de Muestras Biológicas , Grupos Minoritarios , Hipertensión/epidemiología , Factores de Riesgo
20.
Small ; 20(23): e2311452, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38145341

RESUMEN

The highly selective electrochemical conversion of methanol to formate is of great significance for various clean energy devices, but understanding the structure-to-property relationship remains unclear. Here, the asymmetric charge polarized NiCo prussian blue analogue (NiCo PBA-100) is reported to exhibit remarkable catalytic performance with high current density (210 mA cm-2 @1.65 V vs RHE) and Faraday efficiency (over 90%). Meanwhile, the hybrid water splitting and Zinc-methanol-battery assembled by NiCo PBA-100 display the promoted performance with decent stability. X-ray absorption spectroscopy (XAS) and operando Raman spectroscopy indicate that the asymmetric charge polarization in NiCo PBA leads to more unoccupied states of Ni and occupied states of Co, thereby facilitating the rapid transformation of the high-active catalytic centers. Density functional theory calculations combining operando Fourier transform infrared spectroscopy demonstrate that the final reconstructed catalyst derived by NiCo PBA-100 exhibits rearranged d band properties along with a lowered energy barrier of the rate-determining step and favors the desired formate production.

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