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1.
Nat Rev Genet ; 2024 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-39375560

RESUMEN

Decades of genetic association testing in human cohorts have provided important insights into the genetic architecture and biological underpinnings of complex traits and diseases. However, for certain traits, genome-wide association studies (GWAS) for common SNPs are approaching signal saturation, which underscores the need to explore other types of genetic variation to understand the genetic basis of traits and diseases. Copy number variation (CNV) is an important source of heritability that is well known to functionally affect human traits. Recent technological and computational advances enable the large-scale, genome-wide evaluation of CNVs, with implications for downstream applications such as polygenic risk scoring and drug target identification. Here, we review the current state of CNV-GWAS, discuss current limitations in resource infrastructure that need to be overcome to enable the wider uptake of CNV-GWAS results, highlight emerging opportunities and suggest guidelines and standards for future GWAS for genetic variation beyond SNPs at scale.

2.
Am J Hum Genet ; 110(9): 1482-1495, 2023 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-37652022

RESUMEN

Understanding the penetrance of pathogenic variants identified as secondary findings (SFs) is of paramount importance with the growing availability of genetic testing. We estimated penetrance through large-scale analyses of individuals referred for diagnostic sequencing for hypertrophic cardiomyopathy (HCM; 10,400 affected individuals, 1,332 variants) and dilated cardiomyopathy (DCM; 2,564 affected individuals, 663 variants), using a cross-sectional approach comparing allele frequencies against reference populations (293,226 participants from UK Biobank and gnomAD). We generated updated prevalence estimates for HCM (1:543) and DCM (1:220). In aggregate, the penetrance by late adulthood of rare, pathogenic variants (23% for HCM, 35% for DCM) and likely pathogenic variants (7% for HCM, 10% for DCM) was substantial for dominant cardiomyopathy (CM). Penetrance was significantly higher for variant subgroups annotated as loss of function or ultra-rare and for males compared to females for variants in HCM-associated genes. We estimated variant-specific penetrance for 316 recurrent variants most likely to be identified as SFs (found in 51% of HCM- and 17% of DCM-affected individuals). 49 variants were observed at least ten times (14% of affected individuals) in HCM-associated genes. Median penetrance was 14.6% (±14.4% SD). We explore estimates of penetrance by age, sex, and ancestry and simulate the impact of including future cohorts. This dataset reports penetrance of individual variants at scale and will inform the management of individuals undergoing genetic screening for SFs. While most variants had low penetrance and the costs and harms of screening are unclear, some individuals with highly penetrant variants may benefit from SFs.


Asunto(s)
Cardiomiopatías , Cardiomiopatía Dilatada , Cardiomiopatía Hipertrófica , Femenino , Masculino , Humanos , Adulto , Penetrancia , Cardiomiopatías/genética , Cardiomiopatía Dilatada/genética , Frecuencia de los Genes
3.
Gastroenterology ; 166(3): 466-482, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38065340

RESUMEN

BACKGROUND & AIMS: Although immunotherapy shows substantial advancement in colorectal cancer (CRC) with microsatellite instability high, it has limited efficacy for CRC with microsatellite stability (MSS). Identifying combinations that reverse immune suppression and prime MSS tumors for current immunotherapy approaches remains an urgent need. METHODS: An in vitro CRISPR screen was performed using coculture models of primary tumor cells and autologous immune cells from MSS CRC patients to identify epigenetic targets that could enhance immunotherapy efficacy in MSS tumors. RESULTS: We revealed EHMT2, a histone methyltransferase, as a potential target for MSS CRC. EHMT2 inhibition transformed the immunosuppressive microenvironment of MSS tumors into an immunomodulatory one by altering cytokine expression, leading to T-cell-mediated cytotoxicity activation and improved responsiveness to anti-PD1 treatment. We observed galectin-7 up-regulation upon EHMT2 inhibition, which converted a "cold" MSS tumor environment into a T-cell-inflamed one. Mechanistically, CHD4 repressed galectin-7 expression by recruiting EHMT2 to form a cotranscriptional silencing complex. Galectin-7 administration enhanced anti-PD1 efficacy in MSS CRC, serving as a potent adjunct cytokine therapy. CONCLUSIONS: Our findings suggest that targeting the EHMT2/galectin-7 axis could provide a novel combination strategy for immunotherapy in MSS CRC.


Asunto(s)
Neoplasias Colorrectales , Humanos , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Inmunoterapia , Citocinas , Galectinas/genética , Repeticiones de Microsatélite , Inestabilidad de Microsatélites , Microambiente Tumoral , Antígenos de Histocompatibilidad , N-Metiltransferasa de Histona-Lisina
4.
Development ; 149(21)2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-36178075

RESUMEN

Neurodevelopmental disorders ranging from autism to intellectual disability display sex-biased prevalence and phenotypical presentations. Despite increasing knowledge about temporospatial cortical map development and genetic variants linked to neurodevelopmental disorders, when and how sex-biased neural circuit derailment may arise in diseased brain remain unknown. Here, we identify in mice that serotonin uptake transporter (SERT) in non-serotonergic neurons - hippocampal and prefrontal pyramidal neurons - confers sex-biased effects specifically during neural circuit development. A set of gradient-patterned CA3 pyramidal neurons transiently express SERT to clear extracellular serotonin, coinciding with hippocampal synaptic circuit establishment. Ablating pyramidal neuron SERT (SERTPyramidΔ) alters dendritic spine developmental trajectory in the hippocampus, and precipitates sex-biased impairments in long-term activity-dependent hippocampal synaptic plasticity and cognitive behaviors. Transcriptomic analyses identify sex-biased alterations in gene sets associated with autism, dendritic spine structure, synaptic function and male-specific enrichment of dysregulated genes in glial cells in early postnatal SERTPyramidΔ hippocampus. Our data suggest that SERT function in these pyramidal neurons underscores a temporal- and brain region-specific regulation of normal sex-dimorphic circuit development and a source for sex-biased vulnerability to cognitive and behavioral impairments. This article has an associated 'The people behind the papers' interview.


Asunto(s)
Proteínas de Transporte de Serotonina en la Membrana Plasmática , Serotonina , Embarazo , Femenino , Masculino , Animales , Ratones , Proteínas de Transporte de Serotonina en la Membrana Plasmática/genética , Proteínas de Transporte de Serotonina en la Membrana Plasmática/metabolismo , Serotonina/metabolismo , Células Piramidales/metabolismo , Hipocampo/metabolismo , Plasticidad Neuronal/fisiología
5.
Bioinformatics ; 40(Suppl 2): ii155-ii164, 2024 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-39230688

RESUMEN

Motivation: Mobile genetic elements (MGEs) are as ubiquitous in nature as they are varied in type, ranging from viral insertions to transposons to incorporated plasmids. Horizontal transfer of MGEs across bacterial species may also pose a significant threat to global health due to their capability to harbor antibiotic resistance genes. However, despite cheap and rapid whole-genome sequencing, the varied nature of MGEs makes it difficult to fully characterize them, and existing methods for detecting MGEs often do not agree on what should count. In this manuscript, we first define and argue in favor of a divergence-based characterization of mobile-genetic elements. Results: Using that paradigm, we present skandiver, a tool designed to efficiently detect MGEs from whole-genome assemblies without the need for gene annotation or markers. skandiver determines mobile elements via genome fragmentation, average nucleotide identity (ANI), and divergence time. By building on the scalable skani software for ANI computation, skandiver can query hundreds of complete assemblies against >65 000 representative genomes in a few minutes and 19 GB memory, providing scalable and efficient method for elucidating mobile element profiles in incomplete, uncharacterized genomic sequences. For isolated and integrated large plasmids (>10 kb), skandiver's recall was 48% and 47%, MobileElementFinder was 59% and 17%, and geNomad was 86% and 32%, respectively. For isolated large plasmids, skandiver's recall (48%) is lower than state-of-the-art reference-based methods geNomad (86%) and MobileElementFinder (59%). However, skandiver achieves higher recall on integrated plasmids and, unlike other methods, without comparing against a curated database, making skandiver suitable for discovery of novel MGEs. AVAILABILITY AND IMPLEMENTATION: https://github.com/YoukaiFromAccounting/skandiver.


Asunto(s)
Secuencias Repetitivas Esparcidas , Programas Informáticos , Genoma Bacteriano , Elementos Transponibles de ADN/genética , Plásmidos/genética
6.
BMC Genomics ; 25(1): 852, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39261785

RESUMEN

BACKGROUND: Low levels of the essential amino acid lysine in maize endosperm is considered to be a major problem regarding the nutritional quality of food and feed. Increasing the lysine content of maize is important to improve the quality of food and feed nutrition. Although the genetic basis of quality protein maize (QPM) has been studied, the further exploration of the quantitative trait loci (QTL) underlying lysine content variation still needs more attention. RESULTS: Eight maize inbred lines with increased lysine content were used to construct four double haploid (DH) populations for identification of QTLs related to lysine content. The lysine content in the four DH populations exhibited continuous and normal distribution. A total of 12 QTLs were identified in a range of 4.42-12.66% in term of individual phenotypic variation explained (PVE) which suggested the quantitative control of lysine content in maize. Five main genes involved in maize lysine biosynthesis pathways in the QTL regions were identified in this study. CONCLUSIONS: The information presented will allow the exploration of candidate genes regulating lysine biosynthesis pathways and be useful for marker-assisted selection and gene pyramiding in high-lysine maize breeding programs.


Asunto(s)
Lisina , Sitios de Carácter Cuantitativo , Zea mays , Zea mays/genética , Zea mays/metabolismo , Lisina/metabolismo , Fenotipo , Haploidia , Mapeo Cromosómico
7.
Apoptosis ; 29(9-10): 1291-1308, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38853203

RESUMEN

Ferroptosis is a form of cell death that is triggered by the presence of ferrous ions and is characterized by lipid peroxidation induced by these ions. The mechanism exhibits distinct morphological characteristics compared to apoptosis, autophagy, and necrosis. A notable aspect of ferroptosis is its ability to inhibit uncontrolled tumor replication and immortalization, especially in malignant, drug-resistant, and metastatic tumors. Additionally, immunotherapy, a novel therapeutic approach for tumors, has been found to have a reciprocal regulatory relationship with ferroptosis in the context of anti-tumor therapy. A comprehensive analysis of ferroptosis and immunotherapy in tumor therapy is presented in this paper, highlighting the potential for mutual adjuvant effects. Specifically, we discuss the mechanisms underlying ferroptosis and immunotherapy, emphasizing their ability to improve the tumor immune microenvironment and enhance immunotherapeutic effects. Furthermore, we investigate how immunotherapeutic factors may increase the sensitivity of tumor cells to ferroptosis. We aim to provide a prospective view of the promising value of combined ferroptosis and immunotherapy in anticancer therapy by elucidating the mutual regulatory network between each.


Asunto(s)
Ferroptosis , Inmunoterapia , Neoplasias , Microambiente Tumoral , Ferroptosis/efectos de los fármacos , Ferroptosis/genética , Humanos , Neoplasias/inmunología , Neoplasias/terapia , Neoplasias/patología , Neoplasias/tratamiento farmacológico , Microambiente Tumoral/inmunología , Microambiente Tumoral/efectos de los fármacos , Animales , Peroxidación de Lípido/efectos de los fármacos
8.
EMBO J ; 39(12): e103181, 2020 06 17.
Artículo en Inglés | MEDLINE | ID: mdl-32368828

RESUMEN

N6-methyladenosine (m6 A) is an abundant nucleotide modification in mRNA, known to regulate mRNA stability, splicing, and translation, but it is unclear whether it is also has a physiological role in the intratumoral microenvironment and cancer drug resistance. Here, we find that METTL3, a primary m6 A methyltransferase, is significantly down-regulated in human sorafenib-resistant hepatocellular carcinoma (HCC). Depletion of METTL3 under hypoxia promotes sorafenib resistance and expression of angiogenesis genes in cultured HCC cells and activates autophagy-associated pathways. Mechanistically, we have identified FOXO3 as a key downstream target of METTL3, with m6 A modification of the FOXO3 mRNA 3'-untranslated region increasing its stability through a YTHDF1-dependent mechanism. Analysis of clinical samples furthermore showed that METTL3 and FOXO3 levels are tightly correlated in HCC patients. In mouse xenograft models, METTL3 depletion significantly enhances sorafenib resistance of HCC by abolishing the identified METTL3-mediated FOXO3 mRNA stabilization, and overexpression of FOXO3 restores m6 A-dependent sorafenib sensitivity. Collectively, our work reveals a critical function for METTL3-mediated m6 A modification in the hypoxic tumor microenvironment and identifies FOXO3 as an important target of m6 A modification in the resistance of HCC to sorafenib therapy.


Asunto(s)
Adenosina/análogos & derivados , Autofagia/efectos de los fármacos , Carcinoma Hepatocelular/metabolismo , Resistencia a Antineoplásicos/efectos de los fármacos , Proteína Forkhead Box O3/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas de Neoplasias/metabolismo , ARN Mensajero/metabolismo , ARN Neoplásico/metabolismo , Sorafenib/farmacología , Adenosina/genética , Adenosina/metabolismo , Animales , Autofagia/genética , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Proteína Forkhead Box O3/genética , Células HEK293 , Células Hep G2 , Células Endoteliales de la Vena Umbilical Humana , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Masculino , Metilación/efectos de los fármacos , Metiltransferasas/genética , Metiltransferasas/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Proteínas de Neoplasias/genética , ARN Mensajero/genética , ARN Neoplásico/genética
9.
J Cell Sci ; 135(15)2022 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-35722742

RESUMEN

Intervertebral disc degeneration (IVDD) is a complex process involving many factors, among which excessive senescence of nucleus pulposus cells is considered to be the main factor. Our previous study found that metformin can inhibit senescence in nucleus pulposus cells; however, the mechanism of such an action was still largely unknown. In the current study, we found that metformin inactivates the cGAS-STING pathway during oxidative stress. Furthermore, knockdown of STING (also known as STING1) suppresses senescence, indicating that metformin might exert its effect through the cGAS-STING pathway. Damaged DNA is a major inducer of the activation of the cGAS-STING pathway. Mechanistically, our study showed that DNA damage was reduced during metformin treatment; however, suppression of autophagy by 3-methyladenine (3-MA) treatment compromised the effect of metformin on DNA damage. In vivo studies also showed that 3-MA might diminish the therapeutic effect of metformin on IVDD. Taken together, our results reveal that metformin may suppress senescence via inactivating the cGAS-STING pathway through autophagy, implying a new application for metformin in cGAS-STING pathway-related diseases.


Asunto(s)
Degeneración del Disco Intervertebral , Metformina , Núcleo Pulposo , Autofagia/fisiología , Senescencia Celular/fisiología , Humanos , Degeneración del Disco Intervertebral/tratamiento farmacológico , Degeneración del Disco Intervertebral/genética , Degeneración del Disco Intervertebral/metabolismo , Proteínas de la Membrana , Metformina/metabolismo , Metformina/farmacología , Metformina/uso terapéutico , Nucleotidiltransferasas/genética , Nucleotidiltransferasas/metabolismo , Núcleo Pulposo/metabolismo
10.
Chembiochem ; : e202400351, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39168826

RESUMEN

Aberrantly-active signal transducer and activator of transcription (Stat)3 has a causal role in many human cancers and represents a validated anticancer drug target, though it has posed significant challenge to drug development. A new small molecule, JKB887, was identified through library screening and is predicted to interact with Lys591, Arg609 and Pro63 in the phospho-tyrosine (pTyr)-binding pocket of the Stat3 SH2 domain. JKB887 inhibited Stat3 DNA-binding activity in vitro in a time-dependent manner, with IC50 of 2.2-4.5 µM at 30-60-min incubation. It directly disrupted both the Stat3 binding to the cognate, high-affinity pTyr (pY) peptide, GpYLPQTV-NH2 in fluorescent polarization assay with IC50 of 3.5-5.5 µM at 60-90-min incubation, and to the IL-6 receptor/gp130 or Src in treated malignant cells. Treatment with JKB887 selectively blocked constitutive Stat3 phosphorylation, nuclear translocation and transcriptional activity, and Stat3-regulated gene expression, and decreased viable cell numbers, cell growth, colony formation, migration, and survival in human or mouse tumor cells. By contrast, JKB887 had minimal effects on Stat1, pErk1/2MAPK, pShc, pJAK2, or pSrc induction, or on cells that do not harbor aberrantly-active Stat3. Additionally, JKB887 inhibited growth of human breast cancer xenografts in mice. JKB887 is a Stat3-selective inhibitor with demonstrable antitumor effects against Stat3-dependent human cancers.

11.
Nat Mater ; 22(5): 619-626, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37037960

RESUMEN

Methanol with 12.5 wt% H2 content is widely considered a liquid hydrogen medium. Taking into account water with 11.1 wt% H2 content, H2 synthesis from the mixture of water and methanol is a promising method for on-demand hydrogen production. We demonstrate an atomic-level catalyst design strategy using the synergy between single atoms and nanodots for H2 production. The PtCu-TiO2 sandwich photocatalyst achieves a remarkable H2 formation rate (2,383.9 µmol h-1) with a high apparent quantum efficiency (99.2%). Furthermore, the oxidation product is a high-value chemical formaldehyde with 98.6% selectivity instead of CO2, leading to a nearly zero-carbon-emission process. Detailed investigations indicate a dual role of the copper atoms: an electron acceptor to facilitate photoelectron transfer to Pt, and a hole acceptor for the selective oxidation of methanol to formaldehyde, thus avoiding over-oxidation to CO2. The synergy between Pt nanodots and Cu single atoms together reduces the activation energy of this process to 13.2 kJ mol-1.

12.
Langmuir ; 2024 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-39446625

RESUMEN

Membrane separation technology is used to treat environmental wastewater, but during the treatment process, the occurrence of membrane fouling greatly affects the treatment efficiency. To address this phenomenon, improve membrane antipollution capabilities, and treat organic wastewater, photocatalysis and membrane separation technology have been coupled, forming a suitable and promising treatment method. Here, we propose a simple strategy to prepare a polyvinylidene fluoride/polyvinyl pyrrolidone nitrogen-doped titanium dioxide fibrous membrane (PVDF/PVP N-doped TiO2 fibrous membrane). The experimental results showed that PVDF and PVP mixed spinning made the fibrous membrane have a unique microstructure, and the superhydrophobic PVDF fibrous membrane was changed into superhydrophilic. In addition, electrospraying technology was used to attach TiO2 nanoparticles (NPs) to the fiber, and nitrogen (N) was doped in this process to improve the photocatalytic activity of the fibrous membrane. Finally, methyl blue solution was used as the target organic pollutant. Under the irradiation of a xenon lamp, 90.05% of methyl blue was removed within 90 min, indicating that the membrane had good photocatalytic performance. In a water contact angle test, the PVDF/PVP N-doped TiO2 fibrous membrane showed superhydrophilicity. The design of a fibrous membrane with high photocatalytic activity and superhydrophilicity properties has great potential for practical application in the purification of industrial wastewater.

13.
Langmuir ; 40(21): 11287-11296, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38748978

RESUMEN

Transition metal oxides are a potential anode material owing to their high theoretical capacity. Nonetheless, their large volume changes and low electrical conductivities lead to poor cycling performance and rate capabilities. In this article, an effective strategy is proposed and developed for preparing a ZnO/N-doped graphene composite (ZnNc/GO-5). The key point of this strategy is to use zinc tetra tert-butyl-naphthalocyanine (ZnNc) as a codoped source of N atoms and zinc ions, and graphene oxide (GO) which is combined with ZnNc by π-π deposition as a carbon matrix. After calcination, ZnO microcrystals coated with N-doped graphene are obtained. The unique features of the composite and synergistic effect between N-doped reduced graphene oxide and ZnO microcrystals enable good electrochemical performance by the composites when used in lithium-ion batteries. As an anode material, the as-synthesized ZnNc/GO-5 composite delivers a high first capacity of 1942.9 mAh g-1 and excellent cyclic stability of 861.4 mAh g-1 after 150 cycles at 100 mA g-1. This strategy may offer a new method of designing the anode materials of lithium-ion batteries and promote the practical use of organic molecules in next-generation lithium-ion batteries.

14.
Cell Mol Biol (Noisy-le-grand) ; 70(8): 207-212, 2024 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-39262240

RESUMEN

The SLC7A11/xCT cystine transporter is intricately linked with ferroptosis. By mediating intracellular cystine flux, it regulates oxidative stress within neoplastic cells, thereby curtailing ferroptosis and influencing the emergence of colorectal cancer. This study aimed to gauge the SLC7A11/xCT expression across various tumorigenic stages in early colorectal adenocarcinoma tissues, shedding light on its specific role in the genesis of these early malignancies. Sixty specimens that underwent endoscopic submucosal dissection (ESD) resection with pathologic diagnosis of colorectal adenocarcinoma were collected. SLC7A11/xCT expression was pinpointed using immunohistochemistry, and correlations with the patients' clinical-pathological features were drawn. Additionally, a comprehensive bioinformatics assessment was undertaken to discern differential SLC7A11/xCT expressions across a spectrum of cancers. Immunohistochemical assessments unveiled a pronounced cytoplasmic SLC7A11/xCT expression, manifesting as a brownish-yellow hue, particularly in nascent colorectal cancer samples. Its expression was discernibly correlated with both patient gender and adenocarcinoma differentiation grade (P<0.05). Nevertheless, factors such as patient age, tumor localization, infiltration depth, diameter, adjacent adenoma histology, its major axis, and dysplasia degree bore no statistical significance with SLC7A11/xCT levels (P>0.05). Bioinformatics insights pointed to an upregulated SLC7A11/xCT expression across diverse malignancies, inclusive of colon adenocarcinoma, esophageal cancer, acute myeloid leukemia, lung squamous cell carcinoma, colorectal cancer, and endometrial cancer (P<0.05). Elevated SLC7A11/xCT expression marks early colorectal adenocarcinoma, with the intensity of this expression being intertwined with the patient's gender and the tumor's differentiation grade. It is postulated that colorectal cancer cells might amplify SLC7A11/xCT to stymie ferroptosis, thus fostering neoplastic proliferation, metastasis, and cellular stemness.


Asunto(s)
Sistema de Transporte de Aminoácidos y+ , Neoplasias Colorrectales , Humanos , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/cirugía , Neoplasias Colorrectales/genética , Femenino , Masculino , Sistema de Transporte de Aminoácidos y+/metabolismo , Sistema de Transporte de Aminoácidos y+/genética , Persona de Mediana Edad , Anciano , Resección Endoscópica de la Mucosa , Adenocarcinoma/patología , Adenocarcinoma/metabolismo , Adenocarcinoma/cirugía , Adenocarcinoma/genética , Inmunohistoquímica , Regulación Neoplásica de la Expresión Génica , Adulto
15.
J Phys Chem A ; 128(23): 4750-4760, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38832647

RESUMEN

The interactions between a magnetic tip and local spin impurities initiate unconventional Kondo phenomena, such as asymmetric suppression or even splitting of the Kondo peak. However, a lack of realistic theoretical models and comprehensive explanations for this phenomenon persists due to the complexity of the interactions. This research employs a joint method of density functional theory (DFT) and hierarchical equation of motion (HEOM) to simulate and contrast the modulation of the spin state and Kondo behavior in the Fe/Cu(100) system with two distinct magnetic tips. A cobalt tip, possessing a larger magnetic moment, incites greater atomic displacement of the iron atom, more notable alterations in electronic structure, and enhanced charge transfer with the environment compared with the control process utilizing a nickel tip. Furthermore, the Kondo resonance undergoes asymmetric splitting as a result of the ferromagnetic correlation between the iron atom and the magnetic tip. The Co tip's higher spin polarization results in a wider spacing between the splitting peaks. This investigation underscores the precision of the DFT + HEOM approach in predicting complex quantum phenomena and explaining the underlying physical principles. This provides valuable theoretical support for developing more sophisticated quantum regulation experiments.

16.
Acta Pharmacol Sin ; 45(2): 223-237, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37715003

RESUMEN

Due to the sustained proliferative potential of cancer cells, inducing cell death is a potential strategy for cancer therapy. Paraptosis is a mode of cell death characterized by endoplasmic reticulum (ER) and/or mitochondrial swelling and cytoplasmic vacuolization, which is less investigated. Considerable evidence shows that paraptosis can be triggered by various chemical compounds, particularly in cancer cells, thus highlighting the potential application of this non-classical mode of cell death in cancer therapy. Despite these findings, there remain significant gaps in our understanding of the role of paraptosis in cancer. In this review, we summarize the current knowledge on chemical compound-induced paraptosis. The ER and mitochondria are the two major responding organelles in chemical compound-induced paraptosis, which can be triggered by the reduction of protein degradation, disruption of sulfhydryl homeostasis, overload of mitochondrial Ca2+, and increased generation of reactive oxygen species. We also discuss the stumbling blocks to the development of this field and the direction for further research. The rational use of paraptosis might help us develop a new paradigm for cancer therapy.


Asunto(s)
Neoplasias , Paraptosis , Línea Celular Tumoral , Muerte Celular , Especies Reactivas de Oxígeno/metabolismo , Retículo Endoplásmico/metabolismo , Apoptosis , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo
17.
Acta Pharmacol Sin ; 45(8): 1701-1714, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38609562

RESUMEN

Signal transducer and activator of transcription 3 (STAT3) plays an important role in the occurrence and progression of tumors, leading to resistance and poor prognosis. Activation of STAT3 signaling is frequently detected in hepatocellular carcinoma (HCC), but potent and less toxic STAT3 inhibitors have not been discovered. Here, based on antisense technology, we designed a series of stabilized modified antisense oligonucleotides targeting STAT3 mRNA (STAT3 ASOs). Treatment with STAT3 ASOs decreased the STAT3 mRNA and protein levels in HCC cells. STAT3 ASOs significantly inhibited the proliferation, survival, migration, and invasion of cancer cells by specifically perturbing STAT3 signaling. Treatment with STAT3 ASOs decreased the tumor burden in an HCC xenograft model. Moreover, aberrant STAT3 signaling activation is one of multiple signaling pathways involved in sorafenib resistance in HCC. STAT3 ASOs effectively sensitized resistant HCC cell lines to sorafenib in vitro and improved the inhibitory potency of sorafenib in a resistant HCC xenograft model. The developed STAT3 ASOs enrich the tools capable of targeting STAT3 and modulating STAT3 activity, serve as a promising strategy for treating HCC and other STAT3-addicted tumors, and alleviate the acquired resistance to sorafenib in HCC patients. A series of novel STAT3 antisense oligonucleotide were designed and showed potent anti-cancer efficacy in hepatocellular carcinoma in vitro and in vivo by targeting STAT3 signaling. Moreover, the selected STAT3 ASOs enhance sorafenib sensitivity in resistant cell model and xenograft model.


Asunto(s)
Antineoplásicos , Carcinoma Hepatocelular , Proliferación Celular , Resistencia a Antineoplásicos , Neoplasias Hepáticas , Factor de Transcripción STAT3 , Sorafenib , Factor de Transcripción STAT3/metabolismo , Factor de Transcripción STAT3/antagonistas & inhibidores , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/metabolismo , Sorafenib/farmacología , Sorafenib/uso terapéutico , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/metabolismo , Animales , Resistencia a Antineoplásicos/efectos de los fármacos , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Proliferación Celular/efectos de los fármacos , Línea Celular Tumoral , Ratones Desnudos , Oligonucleótidos Antisentido/farmacología , Oligonucleótidos Antisentido/uso terapéutico , Ratones , Ratones Endogámicos BALB C , Ensayos Antitumor por Modelo de Xenoinjerto , Movimiento Celular/efectos de los fármacos , Masculino , Transducción de Señal/efectos de los fármacos , Oligonucleótidos/farmacología
18.
Cereb Cortex ; 33(10): 6449-6464, 2023 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-36646459

RESUMEN

Prematurely born infants are deprived of maternal hormones and cared for in the stressful environment of Neonatal Intensive Care Units (NICUs). They suffer from long-lasting deficits in learning and memory. Here, we show that prematurity and associated neonatal stress disrupt dentate gyrus (DG) development and induce long-term cognitive deficits and that these effects are mediated by insulin growth factor-1 (IGF1). Nonmaternal care of premature rabbits increased the number of granule cells and interneurons and reduced neurogenesis, suggesting accelerated premature maturation of DG. However, the density of glutamatergic synapses, mature dendritic spines, and synaptic transmission were reduced in preterm kits compared with full-term controls, indicating that premature synaptic maturation was abnormal. These findings were consistent with cognitive deficits observed in premature rabbits and appeared to be driven by transcriptomic changes in the granule cells. Preterm kits displayed reduced weight, elevated serum cortisol and growth hormone, and higher IGF1 expression in the liver and DG relative to full-term controls. Importantly, blocking IGF-1 receptor in premature kits restored cognitive deficits, increased the density of glutamatergic puncta, and rescued NR2B and PSD95 levels in the DG. Hence, IGF1 inhibition alleviates prematurity-induced cognitive dysfunction and synaptic changes in the DG through modulation of NR2B and PSD95. The study identifies a novel strategy to potentially rescue DG maldevelopment and cognitive dysfunction in premature infants under stress in NICUs.


Asunto(s)
Disfunción Cognitiva , Insulinas , Animales , Conejos , Giro Dentado/metabolismo , Disfunción Cognitiva/etiología , Disfunción Cognitiva/metabolismo , Factores de Transcripción/metabolismo , Cognición , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Insulinas/metabolismo
19.
Environ Res ; 242: 117770, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38029821

RESUMEN

Aerobic granular sludge (AGS) needs a long start-up time and always shows unstable performance when it is used to treat low-strength wastewater. In this study, a rapid static feeding combined with Fe2+ addition as a novel strategy was employed to improve the formation and stability of AGS in treating low-strength wastewater. Fe-AGS was formed within only 7 days and showed favorable pollutant removal capability and settling performance. The ammonia nitrogen (NH4+-N) and chemical oxygen demand (COD) concentration in the effluent were lower than 5 mg/L and 50 mg/L after day 23, respectively. The sludge volume index (SVI) and mixed liquid suspended solids (MLSS) was 37 mL/g and 2.15 g/L on day 50, respectively. Rapid static feeding can accelerate granules formation by promoting the growth of heterotrophic bacteria, but the granules are unstable due to filamentous bacteria overgrowth. Fe2+ addition can inhibit the growth of filamentous bacteria and promote the aggregation of functional bacteria (eg. Nitrosomonas, Nitrolancea, Paracoccus, Diaphorobacter) by enhancing the secretion of extracellular polymeric substances (EPS). This study provides a new way for AGS application in low-strength wastewater treatment.


Asunto(s)
Aguas del Alcantarillado , Aguas Residuales , Aguas del Alcantarillado/microbiología , Eliminación de Residuos Líquidos , Aerobiosis , Reactores Biológicos/microbiología , Nitrógeno
20.
Mol Ther ; 31(2): 517-534, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36307991

RESUMEN

N6-methyladenosine (m6A) is the most pervasive RNA modification and is recognized as a novel epigenetic regulation in RNA metabolism. Although the m6A modification involves various physiological processes, its roles in drug resistance in colorectal cancer (CRC) still remain unknown. We analyzed the RNA expression profile of m6A/A (%) with MRM mass spectrometry in human 5-fluorouracil (5-FU)-resistant CRC tissues, and used the m6A RNA immunoprecipitation assay to validate the m6A-regulated target. Our results have shown that the m6A demethylase FTO was up-regulated in human primary and 5-FU-resistant CRC. Depletion of FTO decreased cell growth, colony formation and metastasis in 5-FU-resistant CRC cells in vitro and in vivo. Mechanistically, we identified SIVA1, a critical apoptotic gene, as a key downstream target of the FTO-mediated m6A demethylation. The m6A demethylation of SIVA1 at the CDS region induced its mRNA degradation via a YTHDF2-dependent mechanism. The SIVA1 levels were negatively correlated with the FTO levels in clinical CRC tissues. Notably, inhibition of FTO significantly reduced the tolerance of 5-FU in 5-FU-resistant CRC cells via the FTO-SIVA1 axis, whereas SIVA1-depletion could restore the m6A-dependent 5-FU sensitivity in CRC cells. In summary, our findings demonstrate a critical role of FTO as an m6A demethylase enhancing chemo-resistance in CRC cells, and suggest that FTO inhibition may restore the sensitivity of chemo-resistant CRC cells to 5-FU.


Asunto(s)
Neoplasias Colorrectales , Epigénesis Genética , Humanos , ARN , Fluorouracilo/farmacología , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/genética , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/metabolismo
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