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1.
Colloids Surf B Biointerfaces ; 241: 114060, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38964275

RESUMO

The conventional silver nanoparticles (Ag NPs) are characterized with high loading rate and stacking phenomenon, leading to shedding caused biotoxicity and low catalytic efficiency. This seriously hinders their application in biomedicine. Here, we modified the highly dispersible Ag NPs and Ag single-atoms (SAs) synthesis by combining the halloysite clay nanotubes (HNTs) and dodecahydro-dodecaborate (closo-[B12H12]2-) to increase the biocompatible properties and decrease the loading rate. This novel Ag single-atom nanoenzyme alongside Ag NPs nanoenzyme avoid the elevated-temperature calcination while maintaining the exceptionally high-level efficiency of Ag utilization via the reducibility and coordination stabilization of closo-[B12H12]2- and HNTs. With theoretical calculation and electron paramagnetic resonance, we confirmed that both Ag SAzymes and Ag NPs in HNT@B12H12@Ag nanoenzyme are capable decompose the H2O2 into hydroxyl radical (·OH). For the application, we investigated the catalytic activity in the tumor cells and antitumor effects of HNT@B12H12@Ag nanoenzyme both in vitro and in vivo, and confirmed that it effectively suppressed melanoma growth through ·OH generation, with limited biotoxicity. This study provides a novel Ag nanoenzyme synthesis approach to increase the possibility of its clinical application.

2.
ACS Appl Mater Interfaces ; 16(26): 32983-32991, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38898566

RESUMO

Chemodynamic therapy (CDT) has received widespread attention as a tumor optical treatment strategy in the field of malignant tumor therapy. Nonmetallic multifunctional nanomaterials as CDT agents, due to their low toxicity, long-lasting effects, and safety characteristics, have promising applications in the integrated diagnosis and treatment of cancer. Here, we modified the supramolecular framework of boron clusters, coupled with a variety of dyes to develop a series of metal-free agent compounds, and demonstrated that these nonmetallic compounds have excellent CDT activities through experiments. Subsequently, the best performing Methylene Blue/[closo-B12H12]2- (MB@B12H12) was used as an example. Through theoretical calculations, electron paramagnetic resonance spectroscopy, and 808 nm light irradiation, we confirmed that MB@B12H12 exhibited photothermal performance and CDT activity further. More importantly, we applied MB@B12H12 to melanoma cells and subcutaneous tumor, demonstrating its effective suppression of melanoma growth in vitro and in vivo through the synergistic effects of photothermal performance and CDT activity. This study emphasizes the generalizability of the coupling of dyes to [closo-B12H12]2- with important clinical translational potential for CDT reagents. Among them, MB@B12H12 may have a brighter future, paving the way for the rapid development of metal-free CDT reagents.


Assuntos
Antineoplásicos , Animais , Camundongos , Antineoplásicos/química , Antineoplásicos/farmacologia , Catálise , Terapia Fototérmica , Linhagem Celular Tumoral , Humanos , Boro/química , Sobrevivência Celular/efeitos dos fármacos , Azul de Metileno/química , Proliferação de Células/efeitos dos fármacos
3.
Nat Commun ; 15(1): 5014, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38866774

RESUMO

Genetic testing is crucial for precision cancer medicine. However, detecting multiple same-site insertions or deletions (indels) is challenging. Here, we introduce CoHIT (Cas12a-based One-for-all High-speed Isothermal Test), a one-pot CRISPR-based assay for indel detection. Leveraging an engineered AsCas12a protein variant with high mismatch tolerance and broad PAM scope, CoHIT can use a single crRNA to detect multiple NPM1 gene c.863_864 4-bp insertions in acute myeloid leukemia (AML). After optimizing multiple parameters, CoHIT achieves a detection limit of 0.01% and rapid results within 30 minutes, without wild-type cross-reactivity. It successfully identifies NPM1 mutations in 30 out of 108 AML patients and demonstrates potential in monitoring minimal residual disease (MRD) through continuous sample analysis from three patients. The CoHIT method is also competent for detecting indels of KIT, BRAF, and EGFR genes. Integration with lateral flow test strips and microfluidic chips highlights CoHIT's adaptability and multiplexing capability, promising significant advancements in clinical cancer diagnostics.


Assuntos
Sistemas CRISPR-Cas , Mutação INDEL , Leucemia Mieloide Aguda , Nucleofosmina , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/diagnóstico , Neoplasia Residual/genética , Neoplasia Residual/diagnóstico , Proteínas Nucleares/genética , Proteínas Proto-Oncogênicas B-raf/genética , Testes Genéticos/métodos , Receptores ErbB/genética , Proteínas de Bactérias , Endodesoxirribonucleases , Proteínas Associadas a CRISPR
4.
Neoplasia ; 53: 101005, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38761506

RESUMO

Colorectal cancer (CRC) stands as a prevalent malignancy globally. A pivotal event in CRC pathogenesis involves the loss-of-function mutation in the APC gene, leading to the formation of benign polyps. Despite the well-established role of APC, the contribution of CUL4B to CRC initiation in the pre-tumorous stage remains poorly understood. In this investigation, we generated a murine model by crossing ApcMin/+ mice with Cul4bΔIEC mice to achieve specific deletion of Cul4b in the gut epithelium against an ApcMin/+ background. By employing histological methods, RNA-sequencing (RNA-seq), and flow cytometry, we assessed alterations and characterized the immune microenvironment. Our results unveiled that CUL4B deficiency in gut epithelium expedited ApcMin/+ adenoma formation. Notably, CUL4B in adenomas restrained the accumulation of tumor-infiltrating myeloid-derived suppressor cells (MDSCs). In vivo inhibition of MDSCs significantly delayed the growth of CUL4B deleted ApcMin/+ adenomas. Furthermore, the addition of MDSCs to in vitro cultured ApcMin/+; Cul4bΔIEC adenoma organoids mitigated their alterations. Mechanistically, CUL4B directly interacted with the promoter of Csf3, the gene encoding granulocyte-colony stimulating factor (G-CSF) by coordinating with PRC2. Inhibiting CUL4B epigenetically activated the expression of G-CSF, promoting the recruitment of MDSCs. These findings offer novel insights into the tumor suppressor-like roles of CUL4B in regulating ApcMin/+ adenomas, suggesting a potential therapeutic strategy for CRC initiation and progression in the context of activated Wnt signaling.


Assuntos
Adenoma , Proteínas Culina , Modelos Animais de Doenças , Células Supressoras Mieloides , Animais , Proteínas Culina/genética , Proteínas Culina/metabolismo , Camundongos , Células Supressoras Mieloides/metabolismo , Células Supressoras Mieloides/patologia , Adenoma/patologia , Adenoma/genética , Adenoma/metabolismo , Proteína da Polipose Adenomatosa do Colo/genética , Humanos , Microambiente Tumoral/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/etiologia , Deleção de Genes , Mucosa Intestinal/patologia , Mucosa Intestinal/metabolismo
5.
Small ; 20(4): e2307029, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37712137

RESUMO

Chemodynamic therapy (CDT) is a highly targeted approach to treat cancer since it converts hydrogen peroxide into harmful hydroxyl radicals (OH·) through Fenton or Fenton-like reactions. However, the systemic toxicity of metal-based CDT agents has limited their clinical applications. Herein, a metal-free CDT agent: 2,4,6-tri(4-pyridyl)-1,3,5-triazine (TPT)/ [closo-B12 H12 ]2- (TPT@ B12 H12 ) is reported. Compared to the traditional metal-based CDT agents, TPT@B12 H12 is free of metal avoiding cumulative toxicity during long-term therapy. Density functional theory (DFT) calculation revealed that TPT@B12 H12 decreased the activation barrier more than 3.5 times being a more effective catalyst than the Fe2+ ion (the Fenton reaction), which decreases the barrier about twice. Mechanismly, the theory calculation indicated that both [B12 H12 ]-· and [TPT-H]2+ have the capacity to decompose hydrogen into 1 O2 , OH·, and O2 -· . With electron paramagnetic resonance and fluorescent probes, it is confirmed that TPT@B12 H12 increases the levels of 1 O2 , OH·, and O2 -· . More importantly, TPT@B12 H12 effectively suppress the melanoma growth both in vitro and in vivo through 1 O2 , OH·, and O2 -· generation. This study specifically highlights the great clinical translational potential of TPT@B12 H12 as a CDT reagent.


Assuntos
Melanoma , Neoplasias , Humanos , Melanoma/tratamento farmacológico , Boro , Corantes Fluorescentes , Hidrogênio , Peróxido de Hidrogênio , Metais , Linhagem Celular Tumoral
6.
J Colloid Interface Sci ; 658: 276-285, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38104410

RESUMO

Chemodynamic therapy (CDT) is an emerging treatment strategy that inhibits tumor growth by catalyzing the generation of reactive oxygen species (ROS), such as hydroxyl radicals (•OH), using specific nanomaterials. Herein, we have developed a new class of iron-based nanomaterials, i.e., iron-based borides (FeB), using the superchaotropic effect of a boron cluster (closo-[B12H12]2-) and organic ligands, followed by high-temperature calcination. Experimental data and theoretical calculations revealed that FeB nanoparticles exhibit a Fenton-like effect, efficiently decomposing hydrogen peroxide into •OH and thus increasing the concentration of ROS. FeB nanomaterials demonstrate excellent catalytic performance, efficiently generate ROS, and exert significant antitumor effects in cell experiments and animal models. Therefore, FeB nanomaterials have considerable potential for application in tumor treatment and offer new insights for the development of novel and efficient cancer therapy strategies.


Assuntos
Nanopartículas , Neoplasias , Animais , Espécies Reativas de Oxigênio , Catálise , Peróxido de Hidrogênio , Ferro , Neoplasias/tratamento farmacológico , Carbono , Linhagem Celular Tumoral
7.
J Zhejiang Univ Sci B ; 24(3): 232-247, 2023 Mar 15.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-36915999

RESUMO

Drastic surges in intracellular reactive oxygen species (ROS) induce cell apoptosis, while most chemotherapy drugs lead to the accumulation of ROS. Here, we constructed an organic compound, arsenical N-|(4-(1,3,2-dithiarsinan-2-yl)phenyl)acrylamide (AAZ2), which could prompt the ROS to trigger mitochondrial-dependent apoptosis in gastric cancer (GC). Mechanistically, by targeting pyruvate dehydrogenase kinase 1 (PDK1), AAZ2 caused metabolism alteration and the imbalance of redox homeostasis, followed by the inhibition of phosphoinositide-3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway and leading to the activation of B-cell lymphoma 2 (Bcl2)/Bcl2-associated X (Bax)/caspase-9 (Cas9)/Cas3 cascades. Importantly, our in vivo data demonstrated that AAZ2 could inhibit the growth of GC xenograft. Overall, our data suggested that AAZ2 could contribute to metabolic abnormalities, leading to mitochondrial-dependent apoptosis by targeting PDK1 in GC.


Assuntos
Transdução de Sinais , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/tratamento farmacológico , Espécies Reativas de Oxigênio/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Apoptose , Proteínas Proto-Oncogênicas c-bcl-2 , Linhagem Celular Tumoral
8.
Biochem Pharmacol ; 208: 115404, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36592709

RESUMO

Developing novel drugs for gastric cancer (GC) is greatly needed, and a reactive oxygen species (ROS)-modulating strategy has been demonstrated to be useful for cancer treatment. However, no organic arsenical-derived ROS-modulating drug has been developed in GC. Here, we constructed ACZ2 and investigated its efficacy and potential mechanism for GC in vitro and in vivo. Our data showed that ACZ2 could inhibit GC proliferation and cause G2/M phase arrest. Moreover, ACZ2 induced ROS accumulation by depleting glutathione (GSH) and TrxR1, triggering a subsequent ER stress response by activating the PERK/EIF2/ATF4/CHOP signalling pathways, which is a crucial step for ACZ2-mediated apoptosis and autophagy. Vitally, ROS scavenger (NAC) and ER stress inhibitor (4PBA) reversed ACZ2/ROS/ER stress-mediated apoptosis and autophagy. Our in vivo results clearly demonstrated that ACZ2 suppressed tumour growth in a GC xenograft model. Collectively, our data indicated that ACZ2 is a potential agent against GC.


Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular Tumoral , Apoptose , Autofagia , Tiorredoxinas , Estresse do Retículo Endoplasmático
9.
Chemosphere ; 286(Pt 2): 131686, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34333184

RESUMO

Change in water quality was investigated with laboratory-scale ozone-biological activated carbon filters using copper-modified granular activated carbon (Cu/GAC) and unmodified granular activated carbon (GAC). In the first seven days of the experimental period, Cu/GAC removed organic matter more efficiently owing to its enhanced adsorption capacity. As the running time increased, the amount of disinfection by-products (DBPs), dissolved organic carbon, and extracellular polymeric substances (EPS) increased sharply in the effluent of the Cu/GAC filter (CCW). More importantly, the EPS suspended in the CCW exhibited weaker flocculating efficiency and hydrophobicity, causing more active chemical reactions between chlorine and EPS substances. The copper species significantly limited the microbial biomass (0.01 nmol/L adenosine triphosphate) but stimulated the secretion of significant amounts of EPS by microorganisms for self-protection. Furthermore, the microbial community in the bulk water was successfully shaped by Cu/GAC, resulting in a continuous supply of EPS-derived DBP precursors and a sharp rise in chlorine consumption in the downstream drinking water distribution. Therefore, use of modified GAC materials, similar to Cu/GAC, as carrier materials for biological activated carbon (BAC) treatment remains controversial, despite enhanced pollutant adsorption capacity. This is the first study to reveal the mechanism of BAC-modified materials for water quality stability. The study potentially contributes to a comprehensive understanding of the effects of biofilm transformation and microbial community succession on drinking water quality. These results showed that tap water safety risks could be reduced by improving BAC pretreatment in drinking water treatment plants.


Assuntos
Água Potável , Microbiota , Poluentes Químicos da Água , Purificação da Água , Carvão Vegetal , Desinfecção , Matriz Extracelular de Substâncias Poliméricas/química , Filtração , Poluentes Químicos da Água/análise , Qualidade da Água
10.
Elife ; 62017 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-29251597

RESUMO

Odor-preferences are usually influenced by life experiences. However, the neural circuit mechanisms remain unclear. The medial olfactory tubercle (mOT) is involved in both reward and olfaction, whereas the ventral tegmental area (VTA) dopaminergic (DAergic) neurons are considered to be engaged in reward and motivation. Here, we found that the VTA (DAergic)-mOT pathway could be activated by different types of naturalistic rewards as well as odors in DAT-cre mice. Optogenetic activation of the VTA-mOT DAergic fibers was able to elicit preferences for space, location and neutral odor, while pharmacological blockade of the dopamine receptors in the mOT fully prevented the odor-preference formation. Furthermore, inactivation of the mOT-projecting VTA DAergic neurons eliminated the previously formed odor-preference and strongly affected the Go-no go learning efficiency. In summary, our results revealed that the VTA (DAergic)-mOT pathway mediates a variety of naturalistic reward processes and different types of preferences including odor-preference in mice.


Assuntos
Comportamento Animal , Neurônios Dopaminérgicos/fisiologia , Vias Neurais/fisiologia , Odorantes , Tubérculo Olfatório/fisiologia , Área Tegmentar Ventral/fisiologia , Animais , Camundongos , Optogenética
11.
Int J Environ Res Public Health ; 13(1): ijerph13010013, 2015 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-26703702

RESUMO

OBJECTIVE: We have conducted a study to assess the role of environment on the burden of maternal morbidities and mortalities among women using an external exposome approach for the purpose of developing targeted public health interventions to decrease disparities. METHODS: We identified counties in the 48 contiguous USA where observed low birthweight (LBW) rates were higher than expected during a five-year study period. The identification was conducted using a retrospective space-time analysis scan for statistically significant clusters with high or low rates by a Discrete Poisson Model. RESULTS: We observed statistically significant associations of LBW rate with a set of predictive variables. However, in one of the two spatiotemporal models we discovered LBW to be associated with five predictive variables (teen birth rate, adult obesity, uninsured adults, physically unhealthy days, and percent of adults who smoke) in two counties situated in Alabama after adjusting for location changes. Counties with higher than expected LBW rates were similarly associated with two environmental variables (ozone and fine particulate matter). CONCLUSIONS: The county-level predictive measures of LBW offer new insights into spatiotemporal patterns relative to key contributory factors. An external framework provides a promising place-based approach for identifying "hotspots" with implications for designing targeted interventions and control measures to reduce and eliminate health disparities.


Assuntos
Disparidades em Assistência à Saúde/organização & administração , Mortalidade Infantil , Recém-Nascido de Baixo Peso , Recém-Nascido Prematuro , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/mortalidade , Resultado da Gravidez/epidemiologia , Adolescente , Adulto , Alabama/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Morbidade , Gravidez , Gestantes , Nascimento Prematuro/epidemiologia , Prevalência , Características de Residência , Estudos Retrospectivos , Fatores de Risco , Fatores Socioeconômicos , Adulto Jovem
12.
IEEE Trans Cybern ; 45(11): 2472-83, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25494522

RESUMO

In social networks, nodes (or users) interested in specific topics are often influenced by others. The influence is usually associated with a set of nodes rather than a single one. An interesting but challenging task for any given topic and node is to find the set of nodes that represents the source or trigger for the topic and thus identify those nodes that have the greatest influence on the given node as the topic spreads. We find that it is an NP-hard problem. This paper proposes an effective framework to deal with this problem. First, the topic propagation is represented as the Bayesian network. We then construct the propagation model by a variant of the voter model. The probability transition matrix (PTM) algorithm is presented to conduct the probability inference with the complexity O(θ(3)log2θ), while θ is the number nodes in the given graph. To evaluate the PTM algorithm, we conduct extensive experiments on real datasets. The experimental results show that the PTM algorithm is both effective and efficient.

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