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1.
Cell ; 165(6): 1507-1518, 2016 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-27180907

RESUMEN

Tools capable of imaging and perturbing mechanical signaling pathways with fine spatiotemporal resolution have been elusive, despite their importance in diverse cellular processes. The challenge in developing a mechanogenetic toolkit (i.e., selective and quantitative activation of genetically encoded mechanoreceptors) stems from the fact that many mechanically activated processes are localized in space and time yet additionally require mechanical loading to become activated. To address this challenge, we synthesized magnetoplasmonic nanoparticles that can image, localize, and mechanically load targeted proteins with high spatiotemporal resolution. We demonstrate their utility by investigating the cell-surface activation of two mechanoreceptors: Notch and E-cadherin. By measuring cellular responses to a spectrum of spatial, chemical, temporal, and mechanical inputs at the single-molecule and single-cell levels, we reveal how spatial segregation and mechanical force cooperate to direct receptor activation dynamics. This generalizable technique can be used to control and understand diverse mechanosensitive processes in cell signaling. VIDEO ABSTRACT.


Asunto(s)
Técnicas Genéticas , Mecanotransducción Celular , Nanopartículas del Metal , Receptores Notch/metabolismo , Actinas/metabolismo , Cadherinas/metabolismo , Línea Celular , Células Cultivadas , Humanos , Mecanorreceptores/fisiología , Nanopartículas del Metal/química , Microesferas , Técnicas de Sonda Molecular , Proteínas Recombinantes de Fusión/metabolismo , Análisis Espacial , Tiempo
2.
Nature ; 627(8003): 347-357, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38374256

RESUMEN

Type 2 diabetes (T2D) is a heterogeneous disease that develops through diverse pathophysiological processes1,2 and molecular mechanisms that are often specific to cell type3,4. Here, to characterize the genetic contribution to these processes across ancestry groups, we aggregate genome-wide association study data from 2,535,601 individuals (39.7% not of European ancestry), including 428,452 cases of T2D. We identify 1,289 independent association signals at genome-wide significance (P < 5 × 10-8) that map to 611 loci, of which 145 loci are, to our knowledge, previously unreported. We define eight non-overlapping clusters of T2D signals that are characterized by distinct profiles of cardiometabolic trait associations. These clusters are differentially enriched for cell-type-specific regions of open chromatin, including pancreatic islets, adipocytes, endothelial cells and enteroendocrine cells. We build cluster-specific partitioned polygenic scores5 in a further 279,552 individuals of diverse ancestry, including 30,288 cases of T2D, and test their association with T2D-related vascular outcomes. Cluster-specific partitioned polygenic scores are associated with coronary artery disease, peripheral artery disease and end-stage diabetic nephropathy across ancestry groups, highlighting the importance of obesity-related processes in the development of vascular outcomes. Our findings show the value of integrating multi-ancestry genome-wide association study data with single-cell epigenomics to disentangle the aetiological heterogeneity that drives the development and progression of T2D. This might offer a route to optimize global access to genetically informed diabetes care.


Asunto(s)
Diabetes Mellitus Tipo 2 , Progresión de la Enfermedad , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Humanos , Adipocitos/metabolismo , Cromatina/genética , Cromatina/metabolismo , Enfermedad de la Arteria Coronaria/complicaciones , Enfermedad de la Arteria Coronaria/genética , Diabetes Mellitus Tipo 2/clasificación , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/patología , Diabetes Mellitus Tipo 2/fisiopatología , Nefropatías Diabéticas/complicaciones , Nefropatías Diabéticas/genética , Células Endoteliales/metabolismo , Células Enteroendocrinas , Epigenómica , Predisposición Genética a la Enfermedad/genética , Islotes Pancreáticos/metabolismo , Herencia Multifactorial/genética , Enfermedad Arterial Periférica/complicaciones , Enfermedad Arterial Periférica/genética , Análisis de la Célula Individual
3.
Nature ; 614(7946): 88-94, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36653458

RESUMEN

Two-dimensional (2D) materials and their heterostructures show a promising path for next-generation electronics1-3. Nevertheless, 2D-based electronics have not been commercialized, owing mainly to three critical challenges: i) precise kinetic control of layer-by-layer 2D material growth, ii) maintaining a single domain during the growth, and iii) wafer-scale controllability of layer numbers and crystallinity. Here we introduce a deterministic, confined-growth technique that can tackle these three issues simultaneously, thus obtaining wafer-scale single-domain 2D monolayer arrays and their heterostructures on arbitrary substrates. We geometrically confine the growth of the first set of nuclei by defining a selective growth area via patterning SiO2 masks on two-inch substrates. Owing to substantial reduction of the growth duration at the micrometre-scale SiO2 trenches, we obtain wafer-scale single-domain monolayer WSe2 arrays on the arbitrary substrates by filling the trenches via short growth of the first set of nuclei, before the second set of nuclei is introduced, thus without requiring epitaxial seeding. Further growth of transition metal dichalcogenides with the same principle yields the formation of single-domain MoS2/WSe2 heterostructures. Our achievement will lay a strong foundation for 2D materials to fit into industrial settings.

4.
N Engl J Med ; 391(1): 44-55, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38959480

RESUMEN

BACKGROUND: Recurrent cervical cancer is a life-threatening disease, with limited treatment options available when disease progression occurs after first-line combination therapy. METHODS: We conducted a phase 3, multinational, open-label trial of tisotumab vedotin as second- or third-line therapy in patients with recurrent or metastatic cervical cancer. Patients were randomly assigned, in a 1:1 ratio, to receive tisotumab vedotin monotherapy (2.0 mg per kilogram of body weight every 3 weeks) or the investigator's choice of chemotherapy (topotecan, vinorelbine, gemcitabine, irinotecan, or pemetrexed). The primary end point was overall survival. RESULTS: A total of 502 patients underwent randomization (253 were assigned to the tisotumab vedotin group and 249 to the chemotherapy group); the groups were similar with respect to demographic and disease characteristics. The median overall survival was significantly longer in the tisotumab vedotin group than in the chemotherapy group (11.5 months [95% confidence interval {CI}, 9.8 to 14.9] vs. 9.5 months [95% CI, 7.9 to 10.7]), results that represented a 30% lower risk of death with tisotumab vedotin than with chemotherapy (hazard ratio, 0.70; 95% CI, 0.54 to 0.89; two-sided P = 0.004). The median progression-free survival was 4.2 months (95% CI, 4.0 to 4.4) with tisotumab vedotin and 2.9 months (95% CI, 2.6 to 3.1) with chemotherapy (hazard ratio, 0.67; 95% CI, 0.54 to 0.82; two-sided P<0.001). The confirmed objective response rate was 17.8% in the tisotumab vedotin group and 5.2% in the chemotherapy group (odds ratio, 4.0; 95% CI, 2.1 to 7.6; two-sided P<0.001). A total of 98.4% of patients in the tisotumab vedotin group and 99.2% in the chemotherapy group had at least one adverse event that occurred during the treatment period (defined as the period from day 1 of dose 1 until 30 days after the last dose); grade 3 or greater events occurred in 52.0% and 62.3%, respectively. A total of 14.8% of patients stopped tisotumab vedotin treatment because of toxic effects. CONCLUSIONS: In patients with recurrent cervical cancer, second- or third-line treatment with tisotumab vedotin resulted in significantly greater efficacy than chemotherapy. (Funded by Genmab and Seagen [acquired by Pfizer]; innovaTV 301 ClinicalTrials.gov number, NCT04697628.).


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Recurrencia Local de Neoplasia , Neoplasias del Cuello Uterino , Humanos , Femenino , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/mortalidad , Persona de Mediana Edad , Recurrencia Local de Neoplasia/tratamiento farmacológico , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Estimación de Kaplan-Meier , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales/administración & dosificación , Análisis de Supervivencia , Supervivencia sin Progresión , Anciano de 80 o más Años
5.
N Engl J Med ; 390(5): 397-408, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38294972

RESUMEN

BACKGROUND: Butantan-Dengue Vaccine (Butantan-DV) is an investigational, single-dose, live, attenuated, tetravalent vaccine against dengue disease, but data on its overall efficacy are needed. METHODS: In an ongoing phase 3, double-blind trial in Brazil, we randomly assigned participants to receive Butantan-DV or placebo, with stratification according to age (2 to 6 years, 7 to 17 years, and 18 to 59 years); 5 years of follow-up is planned. The objectives of the trial were to evaluate overall vaccine efficacy against symptomatic, virologically confirmed dengue of any serotype occurring more than 28 days after vaccination (the primary efficacy end point), regardless of serostatus at baseline, and to describe safety up to day 21 (the primary safety end point). Here, vaccine efficacy was assessed on the basis of 2 years of follow-up for each participant, and safety as solicited vaccine-related adverse events reported up to day 21 after injection. Key secondary objectives were to assess vaccine efficacy among participants according to dengue serostatus at baseline and according to the dengue viral serotype; efficacy according to age was also assessed. RESULTS: Over a 3-year enrollment period, 16,235 participants received either Butantan-DV (10,259 participants) or placebo (5976 participants). The overall 2-year vaccine efficacy was 79.6% (95% confidence interval [CI], 70.0 to 86.3) - 73.6% (95% CI, 57.6 to 83.7) among participants with no evidence of previous dengue exposure and 89.2% (95% CI, 77.6 to 95.6) among those with a history of exposure. Vaccine efficacy was 80.1% (95% CI, 66.0 to 88.4) among participants 2 to 6 years of age, 77.8% (95% CI, 55.6 to 89.6) among those 7 to 17 years of age, and 90.0% (95% CI, 68.2 to 97.5) among those 18 to 59 years of age. Efficacy against DENV-1 was 89.5% (95% CI, 78.7 to 95.0) and against DENV-2 was 69.6% (95% CI, 50.8 to 81.5). DENV-3 and DENV-4 were not detected during the follow-up period. Solicited systemic vaccine- or placebo-related adverse events within 21 days after injection were more common with Butantan-DV than with placebo (58.3% of participants, vs. 45.6%). CONCLUSIONS: A single dose of Butantan-DV prevented symptomatic DENV-1 and DENV-2, regardless of dengue serostatus at baseline, through 2 years of follow-up. (Funded by Instituto Butantan and others; DEN-03-IB ClinicalTrials.gov number, NCT02406729, and WHO ICTRP number, U1111-1168-8679.).


Asunto(s)
Vacunas contra el Dengue , Virus del Dengue , Dengue , Vacunas Atenuadas , Adulto , Niño , Preescolar , Humanos , Anticuerpos Antivirales , Dengue/prevención & control , Vacunas contra el Dengue/efectos adversos , Vacunas contra el Dengue/uso terapéutico , Virus del Dengue/inmunología , Método Doble Ciego , Vacunación , Vacunas , Vacunas Atenuadas/efectos adversos , Vacunas Atenuadas/uso terapéutico , Brasil , Eficacia de las Vacunas , Adolescente , Adulto Joven , Persona de Mediana Edad , Estudios de Seguimiento
7.
Cell ; 149(6): 1284-97, 2012 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-22632761

RESUMEN

Selective targeting of cancer stem cells (CSCs) offers promise for a new generation of therapeutics. However, assays for both human CSCs and normal stem cells that are amenable to robust biological screens are limited. Using a discovery platform that reveals differences between neoplastic and normal human pluripotent stem cells (hPSC), we identify small molecules from libraries of known compounds that induce differentiation to overcome neoplastic self-renewal. Surprisingly, thioridazine, an antipsychotic drug, selectively targets the neoplastic cells, and impairs human somatic CSCs capable of in vivo leukemic disease initiation while having no effect on normal blood SCs. The drug antagonizes dopamine receptors that are expressed on CSCs and on breast cancer cells as well. These results suggest that dopamine receptors may serve as a biomarker for diverse malignancies, demonstrate the utility of using neoplastic hPSCs for identifying CSC-targeting drugs, and provide support for the use of differentiation as a therapeutic strategy.


Asunto(s)
Antineoplásicos/farmacología , Antagonistas de Dopamina/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Células Madre Neoplásicas/efectos de los fármacos , Tioridazina/farmacología , Animales , Citarabina/farmacología , Humanos , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/patología , Mefloquina/farmacología , Ratones , Células Madre Pluripotentes/efectos de los fármacos , Piranos/farmacología
8.
Nature ; 592(7852): 86-92, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33473216

RESUMEN

The anatomy of the mammalian visual system, from the retina to the neocortex, is organized hierarchically1. However, direct observation of cellular-level functional interactions across this hierarchy is lacking due to the challenge of simultaneously recording activity across numerous regions. Here we describe a large, open dataset-part of the Allen Brain Observatory2-that surveys spiking from tens of thousands of units in six cortical and two thalamic regions in the brains of mice responding to a battery of visual stimuli. Using cross-correlation analysis, we reveal that the organization of inter-area functional connectivity during visual stimulation mirrors the anatomical hierarchy from the Allen Mouse Brain Connectivity Atlas3. We find that four classical hierarchical measures-response latency, receptive-field size, phase-locking to drifting gratings and response decay timescale-are all correlated with the hierarchy. Moreover, recordings obtained during a visual task reveal that the correlation between neural activity and behavioural choice also increases along the hierarchy. Our study provides a foundation for understanding coding and signal propagation across hierarchically organized cortical and thalamic visual areas.


Asunto(s)
Potenciales de Acción/fisiología , Corteza Visual/anatomía & histología , Corteza Visual/fisiología , Animales , Conjuntos de Datos como Asunto , Electrofisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Estimulación Luminosa , Tálamo/anatomía & histología , Tálamo/citología , Tálamo/fisiología , Corteza Visual/citología
9.
N Engl J Med ; 389(23): 2162-2174, 2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38055253

RESUMEN

BACKGROUND: Mirvetuximab soravtansine-gynx (MIRV), a first-in-class antibody-drug conjugate targeting folate receptor α (FRα), is approved for the treatment of platinum-resistant ovarian cancer in the United States. METHODS: We conducted a phase 3, global, confirmatory, open-label, randomized, controlled trial to compare the efficacy and safety of MIRV with the investigator's choice of chemotherapy in the treatment of platinum-resistant, high-grade serous ovarian cancer. Participants who had previously received one to three lines of therapy and had high FRα tumor expression (≥75% of cells with ≥2+ staining intensity) were randomly assigned in a 1:1 ratio to receive MIRV (6 mg per kilogram of adjusted ideal body weight every 3 weeks) or chemotherapy (paclitaxel, pegylated liposomal doxorubicin, or topotecan). The primary end point was investigator-assessed progression-free survival; key secondary analytic end points included objective response, overall survival, and participant-reported outcomes. RESULTS: A total of 453 participants underwent randomization; 227 were assigned to the MIRV group and 226 to the chemotherapy group. The median progression-free survival was 5.62 months (95% confidence interval [CI], 4.34 to 5.95) with MIRV and 3.98 months (95% CI, 2.86 to 4.47) with chemotherapy (P<0.001). An objective response occurred in 42.3% of the participants in the MIRV group and in 15.9% of those in the chemotherapy group (odds ratio, 3.81; 95% CI, 2.44 to 5.94; P<0.001). Overall survival was significantly longer with MIRV than with chemotherapy (median, 16.46 months vs. 12.75 months; hazard ratio for death, 0.67; 95% CI, 0.50 to 0.89; P = 0.005). During the treatment period, fewer adverse events of grade 3 or higher occurred with MIRV than with chemotherapy (41.7% vs. 54.1%), as did serious adverse events of any grade (23.9% vs. 32.9%) and events leading to discontinuation (9.2% vs. 15.9%). CONCLUSIONS: Among participants with platinum-resistant, FRα-positive ovarian cancer, treatment with MIRV showed a significant benefit over chemotherapy with respect to progression-free and overall survival and objective response. (Funded by ImmunoGen; MIRASOL ClinicalTrials.gov number, NCT04209855.).


Asunto(s)
Carcinoma Epitelial de Ovario , Maitansina , Neoplasias Ováricas , Femenino , Humanos , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales Humanizados/efectos adversos , Anticuerpos Monoclonales Humanizados/uso terapéutico , Carcinoma Epitelial de Ovario/tratamiento farmacológico , Carcinoma Epitelial de Ovario/genética , Inmunoconjugados/administración & dosificación , Inmunoconjugados/efectos adversos , Inmunoconjugados/uso terapéutico , Maitansina/administración & dosificación , Maitansina/efectos adversos , Maitansina/análogos & derivados , Maitansina/uso terapéutico , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/genética , Receptor 1 de Folato/antagonistas & inhibidores , Receptor 1 de Folato/genética , Resistencia a Antineoplásicos/genética , Compuestos de Platino/farmacología
10.
Plant Cell ; 35(8): 3035-3052, 2023 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-37225403

RESUMEN

Effective cellular signaling relies on precise spatial localization and dynamic interactions among proteins in specific subcellular compartments or niches, such as cell-to-cell contact sites and junctions. In plants, endogenous and pathogenic proteins gained the ability to target plasmodesmata, membrane-lined cytoplasmic connections, through evolution to regulate or exploit cellular signaling across cell wall boundaries. For example, the receptor-like membrane protein PLASMODESMATA-LOCATED PROTEIN 5 (PDLP5), a potent regulator of plasmodesmal permeability, generates feed-forward or feed-back signals important for plant immunity and root development. However, the molecular features that determine the plasmodesmal association of PDLP5 or other proteins remain largely unknown, and no protein motifs have been identified as plasmodesmal targeting signals. Here, we developed an approach combining custom-built machine-learning algorithms and targeted mutagenesis to examine PDLP5 in Arabidopsis thaliana and Nicotiana benthamiana. We report that PDLP5 and its closely related proteins carry unconventional targeting signals consisting of short stretches of amino acids. PDLP5 contains 2 divergent, tandemly arranged signals, either of which is sufficient for localization and biological function in regulating viral movement through plasmodesmata. Notably, plasmodesmal targeting signals exhibit little sequence conservation but are located similarly proximal to the membrane. These features appear to be a common theme in plasmodesmal targeting.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Plasmodesmos/metabolismo , Arabidopsis/metabolismo , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Proteínas Portadoras/metabolismo
11.
Nature ; 580(7803): 376-380, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32296182

RESUMEN

Mechanosensory feedback from the digestive tract to the brain is critical for limiting excessive food and water intake, but the underlying gut-brain communication pathways and mechanisms remain poorly understood1-12. Here we show that, in mice, neurons in the parabrachial nucleus that express the prodynorphin gene (hereafter, PBPdyn neurons) monitor the intake of both fluids and solids, using mechanosensory signals that arise from the upper digestive tract. Most individual PBPdyn neurons are activated by ingestion as well as the stimulation of the mouth and stomach, which indicates the representation of integrated sensory signals across distinct parts of the digestive tract. PBPdyn neurons are anatomically connected to the digestive periphery via cranial and spinal pathways; we show that, among these pathways, the vagus nerve conveys stomach-distension signals to PBPdyn neurons. Upon receipt of these signals, these neurons produce aversive and sustained appetite-suppressing signals, which discourages the initiation of feeding and drinking (fully recapitulating the symptoms of gastric distension) in part via signalling to the paraventricular hypothalamus. By contrast, inhibiting the same population of PBPdyn neurons induces overconsumption only if a drive for ingestion exists, which confirms that these neurons mediate negative feedback signalling. Our findings reveal a neural mechanism that underlies the mechanosensory monitoring of ingestion and negative feedback control of intake behaviours upon distension of the digestive tract.


Asunto(s)
Ingestión de Alimentos , Retroalimentación , Neuronas/fisiología , Animales , Encefalinas/genética , Encefalinas/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Tracto Gastrointestinal Superior/fisiología
12.
J Neurosci ; 44(16)2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38413232

RESUMEN

Amyotrophic lateral sclerosis (ALS) is a debilitating neurodegenerative disorder marked by progressive motor neuron degeneration and muscle denervation. A recent transcriptomic study integrating a wide range of human ALS samples revealed that the upregulation of p53, a downstream target of inflammatory stress, is commonly detected in familial and sporadic ALS cases by a mechanism linked to a transactive response DNA-binding protein 43 (TDP-43) dysfunction. In this study, we show that prolonged interferon-gamma (IFNγ) treatment of human induced pluripotent stem cell-derived spinal motor neurons results in a severe cytoplasmic aggregation of TDP-43. TDP-43 dysfunction resulting from either IFNγ exposure or an ALS-associated TDP-43 mutation was associated with the activation of the p53 pathway. This was accompanied by the hyperactivation of neuronal firing, followed by the complete loss of their electrophysiological function. Through a comparative single-cell transcriptome analysis, we have identified significant alterations in ALS-associated genes in motor neurons exposed to IFNγ, implicating their direct involvement in ALS pathology. Interestingly, IFNγ was found to induce significant levels of programmed death-ligand 1 (PD-L1) expression in motor neurons without affecting the levels of any other immune checkpoint proteins. This finding suggests a potential role of excessive PD-L1 expression in ALS development, given that PD-L1 was recently reported to impair neuronal firing ability in mice. Our findings suggest that exposing motor neurons to IFNγ could directly derive ALS pathogenesis, even without the presence of the inherent genetic mutation or functional glia component. Furthermore, this study provides a comprehensive list of potential candidate genes for future immunotherapeutic targets with which to treat sporadic forms of ALS, which account for 90% of all reported cases.


Asunto(s)
Esclerosis Amiotrófica Lateral , Células Madre Pluripotentes Inducidas , Animales , Humanos , Ratones , Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/metabolismo , Esclerosis Amiotrófica Lateral/patología , Antígeno B7-H1/metabolismo , Biomarcadores , Proteínas de Unión al ADN/genética , Células Madre Pluripotentes Inducidas/metabolismo , Interferón gamma/metabolismo , Interferón gamma/farmacología , Neuronas Motoras/efectos de los fármacos , Neuronas Motoras/metabolismo , Neuronas Motoras/patología , Proteína p53 Supresora de Tumor/metabolismo
13.
Lancet ; 403(10434): 1341-1350, 2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38521086

RESUMEN

BACKGROUND: Pembrolizumab has shown efficacy in persistent, recurrent, or metastatic cervical cancer. The effect of chemoradiotherapy might be enhanced by immunotherapy. In this phase 3 trial, we assessed the efficacy and safety of adding pembrolizumab to chemoradiotherapy in locally advanced cervical cancer. METHODS: In this randomised, double-blind, placebo-controlled, phase 3 ENGOT-cx11/GOG-3047/KEYNOTE-A18 clinical trial, adults (age ≥18 years) at 176 medical centres in 30 countries with newly diagnosed, high-risk, locally advanced cervical cancer were randomly assigned (1:1) using an interactive voice-response system with integrated web response to receive 5 cycles of pembrolizumab (200 mg) or placebo every 3 weeks plus chemoradiotherapy, followed by 15 cycles of pembrolizumab (400 mg) or placebo every 6 weeks. Randomisation was stratified by planned external beam radiotherapy type (intensity-modulated radiotherapy or volumetric-modulated arc therapy vs non-intensity-modulated radiotherapy or non-volumetric-modulated arc therapy), cervical cancer stage at screening (International Federation of Gynecology and Obstetrics 2014 stage IB2-IIB node positive vs stage III-IVA), and planned total radiotherapy (external beam radiotherapy plus brachytherapy) dose (<70 Gy vs ≥70 Gy equivalent dose in 2 Gy fractions). Primary endpoints were progression-free survival per Response Evaluation Criteria in Solid Tumours version 1.1-by investigator or by histopathologic confirmation of suspected disease progression-and overall survival. Primary analysis was conducted in the intention-to-treat population, which included all randomly allocated participants. Safety was assessed in the as-treated population, which included all randomly allocated patients who received at least one dose of study treatment. This study is registered with ClinicalTrials.gov, NCT04221945, and is closed to new participants. FINDINGS: Between June 9, 2020, and Dec 15, 2022, 1060 participants were randomly assigned to treatment, with 529 assigned to the pembrolizumab-chemoradiotherapy group and 531 to the placebo-chemoradiotherapy group. At data cutoff (Jan 9, 2023), median follow-up was 17·9 months (IQR 11·3-22·3) in both treatment groups. Median progression-free survival was not reached in either group; rates at 24 months were 68% in the pembrolizumab-chemoradiotherapy group versus 57% in the placebo-chemoradiotherapy group. The hazard ratio (HR) for disease progression or death was 0·70 (95% CI 0·55-0·89, p=0·0020), meeting the protocol-specified primary objective. Overall survival at 24 months was 87% in the pembrolizumab-chemoradiotherapy group and 81% in the placebo-chemoradiotherapy group (information fraction 42·9%). The HR for death was 0·73 (0·49-1·07); these data have not crossed the boundary of statistical significance. Grade 3 or higher adverse event rates were 75% in the pembrolizumab-chemoradiotherapy group and 69% in the placebo-chemoradiotherapy group. INTERPRETATION: Pembrolizumab plus chemoradiotherapy significantly improved progression-free survival in patients with newly diagnosed, high-risk, locally advanced cervical cancer. FUNDING: Merck Sharp & Dohme, a subsidiary of Merck & Co (MSD).


Asunto(s)
Neoplasias del Cuello Uterino , Adulto , Femenino , Humanos , Adolescente , Neoplasias del Cuello Uterino/terapia , Anticuerpos Monoclonales Humanizados/efectos adversos , Quimioradioterapia , Progresión de la Enfermedad , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Método Doble Ciego
14.
Am J Pathol ; 194(7): 1306-1316, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38588851

RESUMEN

The role of the phosphatidylinositol 3-kinase (PI3K)/Akt pathway in renal cell carcinoma (RCC) progression, metastasis, and resistance to therapies has not been investigated thoroughly. Transcription factor E3 (TFE3) expression is related to a poorer prognosis and tumor microenvironment in patients with RCC. This study aimed to determine the relationship between TFE3 and the PI3K/Akt pathway. TFE3 down-regulation was achieved by transient transfection of siRNA and shRNA in UOK146 cells. TFE3 overexpression was induced by transient transfection with pcDNA3.1 encoding the constitutively active form of TFE3. The cells were treated with mammalian target of rapamycin (mTOR) and PI3K inhibitors. Western blot was performed to detect TFE3, programmed death-ligand 1, phospho-Akt, and Akt. Phospho-Akt expression increased significantly upon TFE3 down-regulation, and decreased significantly upon up-regulation. When RCC cells were treated with a PI3K inhibitor (LY294002), TFE3 expression increased and phospho-Akt expression decreased. Data from this study indicate that TFE3 plays a role in the PI3K/Akt pathway in RCC. The results of this study suggest that PI3K/Akt inhibitors may aid in the treatment of patients with RCC by affecting the tumor microenvironment.


Asunto(s)
Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice , Carcinoma de Células Renales , Neoplasias Renales , Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Serina-Treonina Quinasas TOR , Microambiente Tumoral , Humanos , Carcinoma de Células Renales/patología , Carcinoma de Células Renales/metabolismo , Carcinoma de Células Renales/genética , Serina-Treonina Quinasas TOR/metabolismo , Microambiente Tumoral/fisiología , Neoplasias Renales/patología , Neoplasias Renales/metabolismo , Neoplasias Renales/genética , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/fisiología , Línea Celular Tumoral , Fosfatidilinositol 3-Quinasas/metabolismo , Regulación Neoplásica de la Expresión Génica
15.
Cell ; 142(5): 682-5, 2010 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-20813257

RESUMEN

It has been suggested that a specific pattern of histone posttranslational modifications and their crosstalk may constitute a code that determines transcriptional outcomes. However, recent studies indicate that histone modifications have context-dependent effects, making their interplay more like a language within the chromatin signaling pathway than a code.


Asunto(s)
Cromatina/metabolismo , Histonas/metabolismo , Procesamiento Proteico-Postraduccional , Código de Histonas , Fosforilación , Transcripción Genética
16.
Nucleic Acids Res ; 51(18): 10026-10040, 2023 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-37650645

RESUMEN

Thermococcus onnurineus NA1, a hyperthermophilic carboxydotrophic archaeon, produces H2 through CO oxidation catalyzed by proteins encoded in a carbon monoxide dehydrogenase (CODH) gene cluster. TON_1525 with a DNA-binding helix-turn-helix (HTH) motif is a putative repressor regulating the transcriptional expression of the codh gene cluster. The T55I mutation in TON_1525 led to enhanced H2 production accompanied by the increased expression of genes in the codh cluster. Here, TON_1525 was demonstrated to be a dimer. Monomeric TON_1525 adopts a novel 'eighth note' symbol-like fold (referred to as 'eighth note' fold regulator, EnfR), and the dimerization mode of EnfR is unique in that it has no resemblance to structures in the Protein Data Bank. According to footprinting and gel shift assays, dimeric EnfR binds to a 36-bp pseudo-palindromic inverted repeat in the promoter region of the codh gene cluster, which is supported by an in silico EnfR/DNA complex model and mutational studies revealing the implication of N-terminal loops as well as HTH motifs in DNA recognition. The DNA-binding affinity of the T55I mutant was lowered by ∼15-fold, for which the conformational change of N-terminal loops is responsible. In addition, transcriptome analysis suggested that EnfR could regulate diverse metabolic processes besides H2 production.

17.
Proc Natl Acad Sci U S A ; 119(34): e2120157119, 2022 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-35969774

RESUMEN

Dynamic regulation of mitochondrial morphology provides cells with the flexibility required to adapt and respond to electron transport chain (ETC) toxins and mitochondrial DNA-linked disease mutations, yet the mechanisms underpinning the regulation of mitochondrial dynamics machinery by these stimuli is poorly understood. Here, we show that pyruvate dehydrogenase kinase 4 (PDK4) is genetically required for cells to undergo rapid mitochondrial fragmentation when challenged with ETC toxins. Moreover, PDK4 overexpression was sufficient to promote mitochondrial fission even in the absence of mitochondrial stress. Importantly, we observed that the PDK4-mediated regulation of mitochondrial fission was independent of its canonical function, i.e., inhibitory phosphorylation of the pyruvate dehydrogenase complex (PDC). Phosphoproteomic screen for PDK4 substrates, followed by nonphosphorylatable and phosphomimetic mutations of the PDK4 site revealed cytoplasmic GTPase, Septin 2 (SEPT2), as the key effector molecule that acts as a receptor for DRP1 in the outer mitochondrial membrane to promote mitochondrial fission. Conversely, inhibition of the PDK4-SEPT2 axis could restore the balance in mitochondrial dynamics and reinvigorates cellular respiration in mitochondrial fusion factor, mitofusin 2-deficient cells. Furthermore, PDK4-mediated mitochondrial reshaping limits mitochondrial bioenergetics and supports cancer cell growth. Our results identify the PDK4-SEPT2-DRP1 axis as a regulator of mitochondrial function at the interface between cellular bioenergetics and mitochondrial dynamics.


Asunto(s)
Dinámicas Mitocondriales , Proteínas Quinasas , Respiración de la Célula/genética , GTP Fosfohidrolasas/genética , Expresión Génica , Mitocondrias/genética , Mitocondrias/metabolismo , Dinámicas Mitocondriales/genética , Proteínas Quinasas/metabolismo
18.
BMC Biol ; 22(1): 105, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38702628

RESUMEN

BACKGROUND: Histone H3K4 tri-methylation (H3K4me3) catalyzed by Set1/COMPASS, is a prominent epigenetic mark found in promoter-proximal regions of actively transcribed genes. H3K4me3 relies on prior monoubiquitination at the histone H2B (H2Bub) by Rad6 and Bre1. Swd2/Cps35, a Set1/COMPASS component, has been proposed as a key player in facilitating H2Bub-dependent H3K4me3. However, a more comprehensive investigation regarding the relationship among Rad6, Swd2, and Set1 is required to further understand the mechanisms and functions of the H3K4 methylation. RESULTS: We investigated the genome-wide occupancy patterns of Rad6, Swd2, and Set1 under various genetic conditions, aiming to clarify the roles of Set1 and Rad6 for occupancy of Swd2. Swd2 peaks appear on both the 5' region and 3' region of genes, which are overlapped with its tightly bound two complexes, Set1 and cleavage and polyadenylation factor (CPF), respectively. In the absence of Rad6/H2Bub, Set1 predominantly localized to the 5' region of genes, while Swd2 lost all the chromatin binding. However, in the absence of Set1, Swd2 occupancy near the 5' region was impaired and rather increased in the 3' region. CONCLUSIONS: This study highlights that the catalytic activity of Rad6 is essential for all the ways of Swd2's binding to the transcribed genes and Set1 redistributes the Swd2 to the 5' region for accomplishments of H3K4me3 in the genome-wide level.


Asunto(s)
N-Metiltransferasa de Histona-Lisina , Histonas , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Histonas/metabolismo , Histonas/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , N-Metiltransferasa de Histona-Lisina/metabolismo , N-Metiltransferasa de Histona-Lisina/genética , Metilación , Adenosina Trifosfatasas/metabolismo , Adenosina Trifosfatasas/genética , Enzimas Ubiquitina-Conjugadoras/metabolismo , Enzimas Ubiquitina-Conjugadoras/genética
19.
Nano Lett ; 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38856974

RESUMEN

In this study, we examined the nanostructured molecular packing and orientations of poly[[N,N'-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5'-(2,2'-bithiophene)] (P(NDI2OD-T2)) films formed on water for the application of nanotechnology-based organic electronic devices. First, the nanoscale molecule-substrate interaction between the polymer and water was modulated by controlling the alkyl side chain length in NDI-based copolymers. Increasing alkyl side chain lengths induced a nanomorphological transition from face-on to edge-on orientation, confirmed by molecular dynamics simulations revealing nanostructural behavior. Second, the nanoscale intermolecular interactions of P(NDI2OD-T2) were controlled by varying the volume ratio of the high-boiling-point additive solvent in the binary solvent blends. As the additive solvent ratio increased, the nanostructured molecular orientation of the P(NDI2OD-T2) films on water changed remarkably from edge-on to bimodal with more face-on crystallites, thereby affecting charge transport. Our finding provides essential insights for precise nanoscale morphological control on water substrates, enabling the formation of high-performance polymer films for organic electronic devices.

20.
Nano Lett ; 24(1): 270-278, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38157214

RESUMEN

Here, we introduce the magneto-mechanical-genetic (MMG)-driven wireless deep brain stimulation (DBS) using magnetic nanostructures for therapeutic benefits in the mouse model of Parkinson's disease (PD). Electrical DBS of the subthalamic nucleus (STN) is an effective therapy for mitigating Parkinson's motor symptoms. However, its broader application is hampered by the requirement for implanted electrodes and the lack of anatomical and cellular specificity. Using the nanoscale magnetic force actuators (m-Torquer), which deliver torque force under rotating magnetic fields to activate pre-encoded Piezo1 ion channels on target neurons, our system enables wireless and STN-specific DBS without implants, addressing key unmet challenges in the DBS field. In both late- and early-stage PD mice, MMG-DBS significantly improved locomotor activity and motor balance by 2-fold compared to untreated PD mice. Moreover, MMG-DBS enabled sustained therapeutic effects. This approach provides a non-invasive and implant-free DBS with cellular targeting capability for the effective treatment of Parkinsonian symptoms.


Asunto(s)
Estimulación Encefálica Profunda , Enfermedad de Parkinson , Trastornos Parkinsonianos , Núcleo Subtalámico , Ratones , Animales , Enfermedad de Parkinson/genética , Enfermedad de Parkinson/terapia , Trastornos Parkinsonianos/terapia , Núcleo Subtalámico/fisiología , Neuronas/fisiología , Canales Iónicos
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