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1.
Cell ; 176(3): 564-580.e19, 2019 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-30580964

RESUMEN

There are still gaps in our understanding of the complex processes by which p53 suppresses tumorigenesis. Here we describe a novel role for p53 in suppressing the mevalonate pathway, which is responsible for biosynthesis of cholesterol and nonsterol isoprenoids. p53 blocks activation of SREBP-2, the master transcriptional regulator of this pathway, by transcriptionally inducing the ABCA1 cholesterol transporter gene. A mouse model of liver cancer reveals that downregulation of mevalonate pathway gene expression by p53 occurs in premalignant hepatocytes, when p53 is needed to actively suppress tumorigenesis. Furthermore, pharmacological or RNAi inhibition of the mevalonate pathway restricts the development of murine hepatocellular carcinomas driven by p53 loss. Like p53 loss, ablation of ABCA1 promotes murine liver tumorigenesis and is associated with increased SREBP-2 maturation. Our findings demonstrate that repression of the mevalonate pathway is a crucial component of p53-mediated liver tumor suppression and outline the mechanism by which this occurs.


Asunto(s)
Ácido Mevalónico/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Transportador 1 de Casete de Unión a ATP/metabolismo , Animales , Línea Celular , Colesterol/metabolismo , Femenino , Genes Supresores de Tumor , Células HCT116 , Hepatocitos/metabolismo , Humanos , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Neoplasias/genética , Regiones Promotoras Genéticas , Proteína 2 de Unión a Elementos Reguladores de Esteroles/metabolismo , Terpenos/metabolismo
2.
Cell ; 172(5): 1007-1021.e17, 2018 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-29474905

RESUMEN

MLL/SET methyltransferases catalyze methylation of histone 3 lysine 4 and play critical roles in development and cancer. We assessed MLL/SET proteins and found that SETD1A is required for survival of acute myeloid leukemia (AML) cells. Mutagenesis studies and CRISPR-Cas9 domain screening show the enzymatic SET domain is not necessary for AML cell survival but that a newly identified region termed the "FLOS" (functional location on SETD1A) domain is indispensable. FLOS disruption suppresses DNA damage response genes and induces p53-dependent apoptosis. The FLOS domain acts as a cyclin-K-binding site that is required for chromosomal recruitment of cyclin K and for DNA-repair-associated gene expression in S phase. These data identify a connection between the chromatin regulator SETD1A and the DNA damage response that is independent of histone methylation and suggests that targeting SETD1A and cyclin K complexes may represent a therapeutic opportunity for AML and, potentially, for other cancers.


Asunto(s)
Ciclinas/metabolismo , Daño del ADN , N-Metiltransferasa de Histona-Lisina/metabolismo , Animales , Biocatálisis , Línea Celular Tumoral , Proliferación Celular , Supervivencia Celular , Ciclinas/genética , Proteína del Grupo de Complementación D2 de la Anemia de Fanconi/genética , Proteína del Grupo de Complementación D2 de la Anemia de Fanconi/metabolismo , Regulación Leucémica de la Expresión Génica , Técnicas de Silenciamiento del Gen , N-Metiltransferasa de Histona-Lisina/química , N-Metiltransferasa de Histona-Lisina/genética , Histonas , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Ratones , Unión Proteica , Dominios Proteicos , Estabilidad Proteica , Transcripción Genética
3.
Cell ; 158(3): 579-92, 2014 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-25083869

RESUMEN

The p53 tumor suppressor coordinates a series of antiproliferative responses that restrict the expansion of malignant cells, and as a consequence, p53 is lost or mutated in the majority of human cancers. Here, we show that p53 restricts expression of the stem and progenitor-cell-associated protein nestin in an Sp1/3 transcription-factor-dependent manner and that Nestin is required for tumor initiation in vivo. Moreover, loss of p53 facilitates dedifferentiation of mature hepatocytes into nestin-positive progenitor-like cells, which are poised to differentiate into hepatocellular carcinomas (HCCs) or cholangiocarcinomas (CCs) in response to lineage-specific mutations that target Wnt and Notch signaling, respectively. Many human HCCs and CCs show elevated nestin expression, which correlates with p53 loss of function and is associated with decreased patient survival. Therefore, transcriptional repression of Nestin by p53 restricts cellular plasticity and tumorigenesis in liver cancer.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Nestina/metabolismo , Animales , Carcinoma Hepatocelular/patología , Transformación Celular Neoplásica , Hepatocitos/metabolismo , Humanos , Neoplasias Hepáticas/patología , Ratones , Pronóstico , Factor de Transcripción Sp1/metabolismo , Factor de Transcripción Sp3/metabolismo , Transcripción Genética , Proteína p53 Supresora de Tumor/metabolismo
4.
Proc Natl Acad Sci U S A ; 121(14): e2302967120, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38547063

RESUMEN

It is well-known that highly reactive hydroxyl radicals (HO•) can be produced by the classic Fenton system and our recently discovered haloquinone/H2O2 system, but rarely from thiol-derivatives. Here, we found, unexpectedly, that HO• can be generated from H2O2 and thiourea dioxide (TUO2), a widely used and environmentally friendly bleaching agent. A carbon-centered radical and sulfite were detected and identified as the transient intermediates, and urea and sulfate as the final products, with the complementary application of electron spin-trapping, oxygen-18 isotope labeling coupled with HPLC/MS analysis. Density functional theory calculations were conducted to further elucidate the detailed pathways for HO• production. Taken together, we proposed that the molecular mechanism for HO• generation by TUO2/H2O2: TUO2 tautomerizes from sulfinic acid into ketone isomer (TUO2-K) through proton transfer, then a nucleophilic addition of H2O2 on the S atom of TUO2-K, forming a S-hydroperoxide intermediate TUO2-OOH, which dissociates homolytically to produce HO•. Our findings represent the first experimental and computational study on an unprecedented new molecular mechanism of HO• production from simple thiol-derived sulfinic acids, which may have broad chemical, environmental, and biomedical significance for future research on the application of the well-known bleaching agent and its analogs.

6.
J Biol Chem ; 300(5): 107257, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38574891

RESUMEN

The Hippo signaling is instrumental in regulating organ size, regeneration, and carcinogenesis. The cytoskeleton emerges as a primary Hippo signaling modulator. Its structural alterations in response to environmental and intrinsic stimuli control Hippo signaling pathway activity. However, the precise mechanisms underlying the cytoskeleton regulation of Hippo signaling are not fully understood. RAP2 GTPase is known to mediate the mechanoresponses of Hippo signaling via activating the core Hippo kinases LATS1/2 through MAP4Ks and MST1/2. Here we show the pivotal role of the reciprocal regulation between RAP2 GTPase and the cytoskeleton in Hippo signaling. RAP2 deletion undermines the responses of the Hippo pathway to external cues tied to RhoA GTPase inhibition and actin cytoskeleton remodeling, such as energy stress and serum deprivation. Notably, RhoA inhibitors and actin disruptors fail to activate LATS1/2 effectively in RAP2-deficient cells. RNA sequencing highlighted differential regulation of both actin and microtubule networks by RAP2 gene deletion. Consistently, Taxol, a microtubule-stabilizing agent, was less effective in activating LATS1/2 and inhibiting cell growth in RAP2 and MAP4K4/6/7 knockout cells. In summary, our findings position RAP2 as a central integrator of cytoskeletal signals for Hippo signaling, which offers new avenues for understanding Hippo regulation and therapeutic interventions in Hippo-impaired cancers.


Asunto(s)
Vía de Señalización Hippo , Proteínas Serina-Treonina Quinasas , Transducción de Señal , Animales , Humanos , Ratones , Citoesqueleto/metabolismo , Microtúbulos/metabolismo , Paclitaxel/farmacología , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas de Unión al GTP rap/metabolismo , Proteínas de Unión al GTP rap/genética , Proteína de Unión al GTP rhoA/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Proteínas Supresoras de Tumor/genética , Fosforilación
7.
Circ Res ; 133(1): 6-21, 2023 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-37232152

RESUMEN

BACKGROUND: Obesity induces cardiomyopathy characterized by hypertrophy and diastolic dysfunction. Whereas mitophagy mediated through an Atg7 (autophagy related 7)-dependent mechanism serves as an essential mechanism to maintain mitochondrial quality during the initial development of obesity cardiomyopathy, Rab9 (Ras-related protein Rab-9A)-dependent alternative mitophagy takes over the role during the chronic phase. Although it has been postulated that DRP1 (dynamin-related protein 1)-mediated mitochondrial fission and consequent separation of the damaged portions of mitochondria are essential for mitophagy, the involvement of DRP1 in mitophagy remains controversial. We investigated whether endogenous DRP1 is essential in mediating the 2 forms of mitophagy during high-fat diet (HFD)-induced obesity cardiomyopathy and, if so, what the underlying mechanisms are. METHODS: Mice were fed either a normal diet or an HFD (60 kcal %fat). Mitophagy was evaluated using cardiac-specific Mito-Keima mice. The role of DRP1 was evaluated using tamoxifen-inducible cardiac-specific Drp1knockout (Drp1 MCM) mice. RESULTS: Mitophagy was increased after 3 weeks of HFD consumption. The induction of mitophagy by HFD consumption was completely abolished in Drp1 MCM mouse hearts, in which both diastolic and systolic dysfunction were exacerbated. The increase in LC3 (microtubule-associated protein 1 light chain 3)-dependent general autophagy and colocalization between LC3 and mitochondrial proteins was abolished in Drp1 MCM mice. Activation of alternative mitophagy was also completely abolished in Drp1 MCM mice during the chronic phase of HFD consumption. DRP1 was phosphorylated at Ser616, localized at the mitochondria-associated membranes, and associated with Rab9 and Fis1 (fission protein 1) only during the chronic, but not acute, phase of HFD consumption. CONCLUSIONS: DRP1 is an essential factor in mitochondrial quality control during obesity cardiomyopathy that controls multiple forms of mitophagy. Although DRP1 regulates conventional mitophagy through a mitochondria-associated membrane-independent mechanism during the acute phase, it acts as a component of the mitophagy machinery at the mitochondria-associated membranes in alternative mitophagy during the chronic phase of HFD consumption.


Asunto(s)
Cardiomiopatías , Mitofagia , Animales , Ratones , Autofagia/fisiología , Cardiomiopatías/genética , Dinaminas/genética , Dinaminas/metabolismo , Corazón , Dinámicas Mitocondriales , Mitofagia/fisiología , Obesidad/genética
8.
Nucleic Acids Res ; 51(7): 3041-3054, 2023 04 24.
Artículo en Inglés | MEDLINE | ID: mdl-36938880

RESUMEN

Targeted and enantioselective delivery of chiral diagnostic-probes and therapeutics into specific compartments inside cells is of utmost importance in the improvement of disease detection and treatment. The classical DNA 'light-switch' ruthenium(II)-polypyridyl complex, [Ru(DIP)2(dppz)]Cl2 (DIP = 4,7-diphenyl-1,10-phenanthroline, dppz = dipyridophenazine) has been shown to be accumulated only in the cytoplasm and membrane, but excluded from its intended nuclear DNA target. In this study, the cationic [Ru(DIP)2(dppz)]2+ is found to be redirected into live-cell nucleus in the presence of lipophilic 3,5-dichlorophenolate or flufenamate counter-anions via ion-pairing mechanism, while maintaining its original DNA recognition characteristics. Interestingly and unexpectedly, further studies show that only the Δ-enantiomer is selectively translocated into nucleus while the Λ-enantiomer remains trapped in cytoplasm, which is found to be mainly due to their differential enantioselective binding affinities with cytoplasmic proteins and nuclear DNA. More importantly, only the nucleus-relocalized Δ-enantiomer can induce obvious DNA damage and cell apoptosis upon prolonged visible-light irradiation. Thus, the use of Δ-enantiomer can significantly reduce the dosage needed for maximal treatment effect. This represents the first report of enantioselective targeting and photosensitization of classical Ru(II) complex via simple ion-pairing with suitable weak acid counter-anions, which opens new opportunities for more effective enantioselective cancer treatment.


Asunto(s)
Núcleo Celular , Rutenio , Estereoisomerismo , Núcleo Celular/metabolismo , Luz , Aniones , ADN/metabolismo
9.
Nucleic Acids Res ; 51(22): 11981-11998, 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-37933856

RESUMEN

Mitochondrial DNA (mtDNA) is known to play a critical role in cellular functions. However, the fluorescent probe enantio-selectively targeting live-cell mtDNA is rare. We recently found that the well-known DNA 'light-switch' [Ru(phen)2dppz]Cl2 can image nuclear DNA in live-cells with chlorophenolic counter-anions via forming lipophilic ion-pairing complex. Interestingly, after washing with fresh-medium, [Ru(phen)2dppz]Cl2 was found to re-localize from nucleus to mitochondria via ABC transporter proteins. Intriguingly, the two enantiomers of [Ru(phen)2dppz]Cl2 were found to bind enantio-selectively with mtDNA in live-cells not only by super-resolution optical microscopy techniques (SIM, STED), but also by biochemical methods (mitochondrial membrane staining with Tomo20-dronpa). Using [Ru(phen)2dppz]Cl2 as the new mtDNA probe, we further found that each mitochondrion containing 1-8 mtDNA molecules are distributed throughout the entire mitochondrial matrix, and there are more nucleoids near nucleus. More interestingly, we found enantio-selective apoptotic cell death was induced by the two enantiomers by prolonged visible light irradiation, and in-situ self-monitoring apoptosis process can be achieved by using the unique 'photo-triggered nuclear translocation' property of the Ru complex. This is the first report on enantio-selective targeting and super-resolution imaging of live-cell mtDNA by a chiral Ru complex via formation and dissociation of ion-pairing complex with suitable counter-anions.


Asunto(s)
ADN Mitocondrial , Microscopía , Rutenio , Aniones , Luz , Mitocondrias , Rutenio/química , Microscopía/métodos
10.
Proc Natl Acad Sci U S A ; 119(17): e2110557119, 2022 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-35442775

RESUMEN

Anticancer drug development campaigns often fail due to an incomplete understanding of the therapeutic index differentiating the efficacy of the agent against the cancer and its on-target toxicities to the host. To address this issue, we established a versatile preclinical platform in which genetically defined cancers are produced using somatic tissue engineering in transgenic mice harboring a doxycycline-inducible short hairpin RNA against the target of interest. In this system, target inhibition is achieved by the addition of doxycycline, enabling simultaneous assessment of efficacy and toxicity in the same animal. As proof of concept, we focused on CDK9­a cancer target whose clinical development has been hampered by compounds with poorly understood target specificity and unacceptable toxicities. We systematically compared phenotypes produced by genetic Cdk9 inhibition to those achieved using a recently developed highly specific small molecule CDK9 inhibitor and found that both perturbations led to robust antitumor responses. Remarkably, nontoxic levels of CDK9 inhibition could achieve significant treatment efficacy, and dose-dependent toxicities produced by prolonged CDK9 suppression were largely reversible upon Cdk9 restoration or drug withdrawal. Overall, these results establish a versatile in vivo target validation platform that can be employed for rapid triaging of therapeutic targets and lend support to efforts aimed at advancing CDK9 inhibitors for cancer therapy.


Asunto(s)
Antineoplásicos , Neoplasias , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Quinasa 9 Dependiente de la Ciclina/metabolismo , Ratones , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Interferencia de ARN
11.
Genes Dev ; 31(13): 1325-1338, 2017 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-28794185

RESUMEN

Deciphering the fundamental mechanisms controlling cardiac specification is critical for our understanding of how heart formation is initiated during embryonic development and for applying stem cell biology to regenerative medicine and disease modeling. Using systematic and unbiased functional screening approaches, we discovered that the Id family of helix-loop-helix proteins is both necessary and sufficient to direct cardiac mesoderm formation in frog embryos and human embryonic stem cells. Mechanistically, Id proteins specify cardiac cell fate by repressing two inhibitors of cardiogenic mesoderm formation-Tcf3 and Foxa2-and activating inducers Evx1, Grrp1, and Mesp1. Most importantly, CRISPR/Cas9-mediated ablation of the entire Id (Id1-4) family in mouse embryos leads to failure of anterior cardiac progenitor specification and the development of heartless embryos. Thus, Id proteins play a central and evolutionarily conserved role during heart formation and provide a novel means to efficiently produce cardiovascular progenitors for regenerative medicine and drug discovery applications.


Asunto(s)
Linaje de la Célula/genética , Corazón/embriología , Proteínas Inhibidoras de la Diferenciación/genética , Proteínas Inhibidoras de la Diferenciación/metabolismo , Organogénesis/genética , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Diferenciación Celular/genética , Línea Celular , Embrión de Mamíferos/citología , Embrión de Mamíferos/embriología , Embrión no Mamífero/citología , Embrión no Mamífero/embriología , Células Madre Embrionarias/citología , Células Madre Embrionarias/fisiología , Edición Génica , Regulación del Desarrollo de la Expresión Génica/genética , Cardiopatías Congénitas/genética , Humanos , Mesodermo/citología , Mesodermo/fisiología , Ratones , Mutación , Semillas , Xenopus laevis/embriología
12.
J Cell Mol Med ; 28(1): e18028, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37985436

RESUMEN

Pathological cardiac hypertrophy is a key contributor to heart failure, and the molecular mechanisms underlying honokiol (HNK)-mediated cardioprotection against this condition remain worth further exploring. This study aims to investigate the effect of HNK on angiotensin II (Ang II)-induced myocardial hypertrophy and elucidate the underlying mechanisms. Sprague-Dawley rats were exposed to Ang II infusion, followed by HNK or vehicle treatment for 4 weeks. Our results showed that HNK treatment protected against Ang II-induced myocardial hypertrophy, fibrosis and dysfunction in vivo and inhibited Ang II-induced hypertrophy in neonatal rat ventricular myocytes in vitro. Mechanistically, HNK suppressed the Ang II-induced Nur77 expression at the transcriptional level and promoted ubiquitination-mediated degradation of Nur77, leading to dissociation of the Nur77-LKB1 complex. This facilitated the translocation of LKB1 into the cytoplasm and activated the LKB1-AMPK pathway. Our findings suggest that HNK attenuates pathological remodelling and cardiac dysfunction induced by Ang II by promoting dissociation of the Nur77-LKB1 complex and subsequent activation of AMPK signalling. This study uncovers a novel role of HNK on the LKB1-AMPK pathway to protect against cardiac hypertrophy.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Compuestos Alílicos , Angiotensina II , Compuestos de Bifenilo , Fenoles , Ratas , Animales , Angiotensina II/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Ratas Sprague-Dawley , Cardiomegalia/metabolismo , Miocitos Cardíacos/metabolismo
13.
Stroke ; 55(3): 660-669, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38299341

RESUMEN

BACKGROUND: Our primary objective was to assess the association between joint exposure to various air pollutants and the risk of ischemic stroke (IS) and the modification of the genetic susceptibility. METHODS: This observational cohort study included 307 304 British participants from the United Kingdom Biobank, who were stroke-free and possessed comprehensive baseline data on genetics, air pollutant exposure, alcohol consumption, and dietary habits. All participants were initially enrolled between 2006 and 2010 and were followed up until 2022. An air pollution score was calculated to assess joint exposure to 5 ambient air pollutants, namely particulate matter with diameters equal to or <2.5 µm, ranging from 2.5 to 10 µm, equal to or <10 µm, as well as nitrogen oxide and nitrogen dioxide. To evaluate individual genetic risk, a polygenic risk score for IS was calculated for each participant. We adjusted for demographic, social, economic, and health covariates. Cox regression models were utilized to estimate the associations between air pollution exposure, polygenic risk score, and the incidence of IS. RESULTS: Over a median follow-up duration of 13.67 years, a total of 2476 initial IS events were detected. The hazard ratios (95% CI) of IS for per 10 µg/m3 increase in particulate matter with diameters equal to or <2.5 µm, ranging from 2.5 to 10 µm, equal to or <10 µm, nitrogen dioxide, and nitrogen oxide were 1.73 (1.33-2.14), 1.24 (0.88-1.70), 1.13 (0.89-1.33), 1.03 (0.98-1.08), and 1.04 (1.02-1.07), respectively. Furthermore, individuals in the highest quintile of the air pollution score exhibited a 29% to 66% higher risk of IS compared with those in the lowest quintile. Notably, participants with both high polygenic risk score and air pollution score had a 131% (95% CI, 85%-189%) greater risk of IS than participants with low polygenic risk score and air pollution score. CONCLUSIONS: Our findings suggested that prolonged joint exposure to air pollutants may contribute to an increased risk of IS, particularly among individuals with elevated genetic susceptibility to IS.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Ambientales , Accidente Cerebrovascular Isquémico , Humanos , Contaminantes Atmosféricos/efectos adversos , Contaminantes Atmosféricos/análisis , Dióxido de Nitrógeno/efectos adversos , Dióxido de Nitrógeno/análisis , Accidente Cerebrovascular Isquémico/inducido químicamente , Biobanco del Reino Unido , Bancos de Muestras Biológicas , Material Particulado/efectos adversos , Material Particulado/análisis , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Óxidos de Nitrógeno , Óxido Nítrico , Puntuación de Riesgo Genético , Exposición a Riesgos Ambientales/efectos adversos
14.
Plant Mol Biol ; 114(3): 45, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38630407

RESUMEN

The recent growth in global warming, soil contamination, and climate instability have widely disturbed ecosystems, and will have a significant negative impact on the growth of plants that produce grains, fruits and woody biomass. To conquer this difficult situation, we need to understand the molecular bias of plant environmental responses and promote development of new technologies for sustainable maintenance of crop production. Accumulated molecular biological data have highlighted the importance of RNA-based mechanisms for plant stress responses. Here, we report the most advanced plant RNA research presented in the 33rd International Conference on Arabidopsis Research (ICAR2023), held as a hybrid event on June 5-9, 2023 in Chiba, Japan, and focused on "Arabidopsis for Sustainable Development Goals". Six workshops/concurrent sessions in ICAR2023 targeted plant RNA biology, and many RNA-related topics could be found in other sessions. In this meeting report, we focus on the workshops/concurrent sessions targeting RNA biology, to share what is happening now at the forefront of plant RNA research.


Asunto(s)
Arabidopsis , Agricultura , Arabidopsis/genética , Ecosistema , ARN de Planta/genética , Suelo
15.
Breast Cancer Res ; 26(1): 100, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38867307

RESUMEN

BACKGROUND: Immunohistochemistry (IHC) and in situ hybridization (ISH) remain standard biomarkers for therapeutic decisions in human epidermal growth factor 2 (HER2)-positive breast cancers (BCs); however, they are insufficient to explain the heterogeneous anti-HER2 response. METHODS: We aimed to investigate the correlation of in situ HER2 RNA expression (isHRE), using RNAscope, with HER2 biomarkers and the impact of isHRE on the pathological complete response (pCR) rates of 278 patients with HER2 IHC/fluorescence ISH (FISH)-positive BC receiving neoadjuvant chemotherapy and anti-HER2 targeted treatment (NCTT). RESULTS: We validated HER2 RNAscope scoring as a semiquantitative method to determine isHRE and showed a positive correlation between RNAscope scores and pCR rates, with particularly different rates between patients with a score of 5 versus 1-4 BCs (66.7% vs. 15.9%, p < 0.0001). There were higher RNAscope scores and pCR rates in patients with HER2 IHC 3 + versus IHC 2+/FISH + BCs and HER2 RNAscope scores and pCR rates showed similar non-linear positive correlations with HER2 copy numbers and HER2/centromere 17 ratios. Moreover, in each HER2-positive IHC/FISH category, higher pCR rates were observed in patients with RNAscope scores of 5 versus 1-4 BC. Patients achieving pCR had BCs with notably higher HER2 RNAscope scores. Multivariate analysis identified HER2 RNAscope 5 as a strong pCR predictor [odds ratio = 10.865, p < 0.001]. The combined impact of multivariate analysis-defined pCR predictors demonstrated that a higher pCR rate was observed in patients with a score of 5 versus a score of 1-4 BCs regardless of the status of hormone receptor and mono-or dual anti-HER2 blockade. CONCUSIONS: Our results demonstrated that high isHRE (RNAscope score 5) is a strong pCR predictor in patients with HER2-positive BCs receiving NCTT, highlighting the complementary role of isHRE in stratifying HER2 status in tissue. Such stratification is relevant to anti-HER2 therapeutic efficacy, particularly using the cutoff of score 1-4 versus 5.


Asunto(s)
Biomarcadores de Tumor , Neoplasias de la Mama , Hibridación Fluorescente in Situ , Terapia Neoadyuvante , Receptor ErbB-2 , Humanos , Receptor ErbB-2/metabolismo , Receptor ErbB-2/genética , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Terapia Neoadyuvante/métodos , Persona de Mediana Edad , Adulto , Biomarcadores de Tumor/metabolismo , Anciano , Resultado del Tratamiento , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Terapia Molecular Dirigida , Inmunohistoquímica , Pronóstico , Trastuzumab/uso terapéutico , Respuesta Patológica Completa
16.
Small ; 20(15): e2307284, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37994259

RESUMEN

High-entropy oxides (HEOs) are promising anode materials for lithium-ion batteries (LIBs), owing to their stable crystal structure, superionic conductivity, and high capacity. In this study, the (Cr, Mn, Fe, Co, and Ni)3O4 HEO via solid-state reaction is prepared. To improve the synthetic efficiency, it is necessary to understand the formation mechanism. Therefore, a high-resolution transmission electron microscopy (HRTEM) is used to record information during calcination at increasing temperature. The overall formation process included MnO2 and NiO aggregation at 500 °C, followed by (Mn, and Ni)3O4 combined with Co3O4 at 600 °C to form (Mn, Co, and Ni)3O4. At higher temperatures, Fe2O3 and Cr2O3 sequentially combined with (Mn, Co, and Ni)3O4 and formed the (Cr, Mn, Fe, Co, Ni)3O4 at 900 °C. In addition, the valence-state-changing mechanisms and ion arrangements of (Cr, Mn, Fe, Co, and Ni)3O4 are determined using electron energy loss spectroscopy (EELS) and extended X-ray absorption fine structure (EXAFS). This study successfully revealed the formation of HEO at atomic scale. The results provide valuable insights for improving the manufacturing process of (Cr, Mn, Fe, Co, and Ni)3O4 HEOs, which is expected to play a vital role in the development of anode materials for next-generation LIBs.

17.
Small ; 20(24): e2311811, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38372500

RESUMEN

Amid growing interest in using body heat for electricity in wearables, creating stretchable devices poses a major challenge. Herein, a hydrogel composed of two core constituents, namely the negatively-charged 2-acrylamido-2-methylpropanesulfonic acid and the zwitterionic (ZI) sulfobetaine acrylamide, is engineered into a double-network hydrogel. This results in a significant enhancement in mechanical properties, with tensile stress and strain of up to 470.3 kPa and 106.6%, respectively. Moreover, the ZI nature of the polymer enables the fabrication of a device with polar thermoelectric properties by modulating the pH. Thus, the ionic Seebeck coefficient (Si) of the ZI hydrogel ranges from -32.6 to 31.7 mV K-1 as the pH is varied from 1 to 14, giving substantial figure of merit (ZTi) values of 3.8 and 3.6, respectively. Moreover, a prototype stretchable ionic thermoelectric supercapacitor incorporating the ZI hydrogel exhibits notable power densities of 1.8 and 0.9 mW m-2 at pH 1 and 14, respectively. Thus, the present work paves the way for the utilization of pH-sensitive, stretchable ZI hydrogels for thermoelectric applications, with a specific focus on harvesting low-grade waste heat within the temperature range of 25-40 °C.

18.
Biol Reprod ; 110(3): 476-489, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38091979

RESUMEN

Recurrent spontaneous abortion, defined as at least three unexplained abortions occurring before the 20-24 week of pregnancy, has a great impact on women's quality of life. Ephrin receptor B4 has been associated with trophoblast function in preeclampsia. The present study aimed to verify the hypothesis that ephrin receptor B4 regulates the biological functions of trophoblasts in recurrent spontaneous abortion and to explore the upstream mechanism. Ephrin receptor B4 was overexpressed in mice with recurrent spontaneous abortion. Moreover, ephrin receptor B4 inhibited trophoblast proliferation, migration, and invasion while promoting apoptosis. Downregulation of early growth response protein 1 expression in mice with recurrent spontaneous abortion led to ephrin receptor B4 overexpression. Poor expression of WT1-associated protein in mice with recurrent spontaneous abortion reduced the modification of early growth response protein 1 mRNA methylation, resulting in decreased early growth response protein 1 mRNA stability and expression. Overexpression of WT1-associated protein reduced the incidence of recurrent spontaneous abortion in mice by controlling the phenotype of trophoblasts, which was reversed by early growth response protein 1 knockdown. All in all, our findings demonstrate that dysregulation of WT1-associated protein contributes to the instability of early growth response protein 1, thereby activating ephrin receptor B4-induced trophoblast dysfunction in recurrent spontaneous abortion. Our study provides novel insights into understanding the molecular pathogenesis of recurrent spontaneous abortion.


Asunto(s)
Aborto Habitual , Aborto Espontáneo , Animales , Femenino , Humanos , Ratones , Embarazo , Aborto Habitual/metabolismo , Aborto Espontáneo/genética , Movimiento Celular , Proliferación Celular , Proteína 1 de la Respuesta de Crecimiento Precoz , Efrinas/metabolismo , Calidad de Vida , Trofoblastos/metabolismo
19.
J Synchrotron Radiat ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38838165

RESUMEN

Understanding the correlation between chemical and microstructural properties is critical for unraveling the fundamental relationship between materials chemistry and physical structures that can benefit materials science and engineering. Here, we demonstrate novel in situ correlative imaging of the X-ray Compton scattering computed tomography (XCS-CT) technique for studying this fundamental relationship. XCS-CT can image light elements that do not usually exhibit strong signals using other X-ray characterization techniques. This paper describes the XCS-CT setup and data analysis method for calculating the valence electron momentum density and lithium-ion concentration, and provides two examples of spatially and temporally resolved chemical properties inside batteries in 3D. XCS-CT was applied to study two types of rechargeable lithium batteries in standard coin cell casings: (1) a lithium-ion battery containing a cathode of bespoke microstructure and liquid electrolyte, and (2) a solid-state battery containing a solid-polymer electrolyte. The XCS-CT technique is beneficial to a wide variety of materials and systems to map chemical composition changes in 3D structures.

20.
Crit Care Med ; 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38780398

RESUMEN

OBJECTIVES: Following current cardiopulmonary resuscitation (CPR) guidelines, which recommend chest compressions at "the center of the chest," ~50% of patients experiencing out-of-hospital cardiac arrest (OHCA) undergo aortic valve (AV) compression, obstructing blood flow. We used resuscitative transesophageal echocardiography (TEE) to elucidate the impact of uncompressed vs. compressed AV on outcomes of adult patients experiencing OHCA. DESIGN: Prospective observational cohort study. SETTING: Single center. PATIENTS: This study included adult OHCA patients undergoing resuscitative TEE in the emergency department. Patients were categorized into AV uncompressed or AV compressed groups based on TEE findings. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The primary outcome was sustained return of spontaneous circulation (ROSC). The secondary outcomes included end-tidal co2 (Etco2) during CPR, any ROSC, survival to ICU and hospital discharge, post-resuscitation withdrawal, and favorable neurologic outcomes at discharge. Additional analyses on intra-arrest arterial blood pressure (ABP) were also conducted. The sample size was pre-estimated at 37 patients/group. From October 2020 to January 2023, 76 patients were enrolled, 39 and 37 in the AV uncompressed and AV compressed groups, respectively. Intergroup baseline characteristics were similar. Compared with the AV compressed group, the AV uncompressed group had a higher probability of sustained ROSC (53.8% vs. 24.3%; adjusted odds ratio [aOR], 4.72; p = 0.010), any ROSC (56.4% vs. 32.4%; aOR, 3.30; p = 0.033), and survival to ICU (33.3% vs. 8.1%; aOR, 6.74; p = 0.010), and recorded higher initial diastolic ABP (33.4 vs. 11.5 mm Hg; p = 0.002) and a larger proportion achieving diastolic ABP greater than 20 mm Hg during CPR (93.8% vs. 33.3%; p < 0.001). The Etco2, post-resuscitation withdrawal, and survival to discharge revealed no significant intergroup differences. No patients were discharged with favorable neurologic outcomes. Uncompressed AV seemed critical for sustained ROSC across all subgroups. CONCLUSIONS: Absence of AV compression during OHCA resuscitation is associated with an increased chance of ROSC and survival to ICU. However, its effect on long-term outcomes remains unclear.

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