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1.
Nanomaterials (Basel) ; 13(17)2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37686998

RESUMO

Lithium-sulfur (Li-S) batteries are regarded as highly promising energy storage devices due to their high theoretical specific capacity and high energy density. Nevertheless, the commercial application of Li-S batteries is still restricted by poor electrochemical performance. Herein, beaded nanofibers (BNFs) consisting of carbon and CoSe2 nanoparticles (CoSe2/C BNFs) were prepared by electrospinning combined with carbonization and selenization. Benefitting from the synergistic effect of physical adsorption and chemical catalysis, the CoSe2/C BNFs can effectively inhibit the shuttle effect of lithium polysulfides and improve the rate performance and cycle stability of Li-S batteries. The three-dimensional conductive network provides a fast electron and ion transport pathway as well as sufficient space for alleviating the volume change. CoSe2 can not only effectively adsorb the lithium polysulfides but also accelerate their conversion reaction. The CoSe2/C BNFs-S cathode has a high reversible discharge specific capacity of 919.2 mAh g-1 at 0.1 C and presents excellent cycle stability with a low-capacity decay rate of 0.05% per cycle for 600 cycles at 1 C. The combination of the beaded carbon nanofibers and polar metal selenides sheds light on designing high-performance sulfur-based cathodes.

2.
FEBS Lett ; 597(8): 1125-1137, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36700826

RESUMO

Head and neck squamous cell carcinoma (HNSCC) is one of the most prevalent cancers worldwide. Heat shock factor 1 (HSF1) is a conserved transcriptional factor that plays a critical role in maintaining cellular proteostasis. However, the role of HSF1 in HNSCC development remains largely unclear. Here, we report that HSF1 promotes forkhead box protein O3a (FOXO3a)-dependent transcription of ΔNp63α (p63 isoform in the p53 family; inhibits cell migration, invasion, and metastasis), which leads to upregulation of cyclin-dependent kinase 4 expression and HNSCC tumour growth. Ablation of HSF1 or treatment with KRIBB11, a specific pharmacological inhibitor of HSF1, significantly suppresses ΔNp63α expression and HNSCC tumour growth. Clinically, the expression of HSF1 is positively correlated with the expression of ΔNp63α in HNSCC tumours. Together, this study demonstrates that the HSF1-ΔNp63α pathway is critically important for HNSCC tumour growth.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Humanos , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Quinase 4 Dependente de Ciclina , Carcinoma de Células Escamosas de Cabeça e Pescoço , Proteínas Supressoras de Tumor/metabolismo , Proteína Forkhead Box O3/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Fatores de Transcrição de Choque Térmico/metabolismo
3.
Front Med (Lausanne) ; 9: 860798, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35433730

RESUMO

Objectives: The purpose of this study was to investigate the baseline independent risk factors for predicting 6-month mortality of patients with anti-melanoma differentiation-associated gene 5 (anti-MDA5)-positive dermatomyositis (DM) and develop a matrix prediction model formed by these risk factors. Methods: The hospitalized patients with DM who completed at least 6-month follow-up were recruited as a derivation cohort. The primary exposure was defined as positive anti-MDA5 at the baseline. The primary outcome was all-cause 6-month mortality after enrollment. A matrix prediction model was developed in the derivation cohort, and another published cohort was used for external validation. Results: In derivation cohort, 82 patients with DM were enrolled (mean age of onset 50 ± 11 years and 63% women), with 40 (49%) showing positive anti-MDA5. Gottron sign/papules (OR: 5.135, 95%CI: 1.489-17.708), arthritis (OR: 5.184, 95%CI: 1.455-18.467), interstitial lung disease (OR: 7.034, 95%CI: 1.157-42.785), and higher level of C4 (OR: 1.010, 95%CI: 1.002-1.017) were the independent associators with positive anti-MDA5 in patients with DM. Patients with anti-MDA5-positive DM had significant higher 6-month all-cause mortality than those with anti-MDA5-negative (30 vs. 0%). Among the patients with anti-MDA5-positive DM, compared to the survivors, non-survivors had significantly advanced age of onset (59 ± 6 years vs. 46 ± 9 years), higher rates of fever (75 vs. 18%), positive carcinoma embryonic antigen (CEA, 75 vs. 14%), higher level of ferritin (median 2,858 ug/L vs. 619 ug/L, all p < 0.05). A stepwise multivariate Cox regression showed that ferritin ≥1,250 µg/L (HR: 10.4, 95%CI: 1.8-59.9), fever (HR: 11.2, 95%CI: 2.5-49.9), and positive CEA (HR: 5.2, 95%CI: 1.0-25.7) were the independent risk factors of 6-month mortality. A matrix prediction model was built to stratify patients with anti-MDA5-positive DM into different subgroups with various probabilities of 6-month mortality risk. In an external validation cohort, the observed 6-month all-cause mortality was 78% in high-risk group, 43% in moderate-risk group, and 25% in low-risk group, which shows good accuracy of the model. Conclusion: Baseline characteristics such as fever, ferritin ≥1,250 µg/L, and positive CEA are the independent risk factors for 6-month all-cause mortality in patients with anti-MDA5-positive DM. A novel matrix prediction model composed of these three clinical indicators is first proposed to provide a chance for the exploration of individual treatment strategies in anti-MDA5-positive DM subgroups with various probabilities of mortality risk.

4.
Front Genet ; 12: 814480, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35047022

RESUMO

Breast cancer (BC) is the most diagnosed cancer and the leading cause of cancer-related deaths in women. The purpose of this study was to develop a prognostic model based on BC-related DNA methylation pattern. A total of 361 BC incidence-related probes (BCIPs) were differentially methylated in blood samples from women at high risk of BC and BC tissues. Twenty-nine of the 361 BCIPs that significantly correlated with BC outcomes were selected to establish the BCIP score. BCIP scores based on BC-related DNA methylation pattern were developed to evaluate the mortality risk of BC. The correlation between overall survival and BCIP scores was assessed using Kaplan-Meier, univariate, and multivariate analyses. In BC, the BCIP score was significantly correlated with malignant BC characteristics and poor outcomes. Furthermore, we assessed the BCIP score-related gene expression profile and observed that genes with expressions associated with the BCIP score were involved in the process of cancer immunity according to GO and KEGG analyses. Using the ESTIMATE and CIBERSORT algorithms, we discovered that BCIP scores were negatively correlated with both T cell infiltration and immune checkpoint inhibitor response markers in BC tissues. Finally, a nomogram comprising the BCIP score and BC prognostic factors was used to establish a prognostic model for patients with BC, while C-index and calibration curves were used to evaluate the effectiveness of the nomogram. A nomogram comprising the BCIP score, tumor size, lymph node status, and molecular subtype was developed to quantify the survival probability of patients with BC. Collectively, our study developed the BCIP score, which correlated with poor outcomes in BC, to portray the variation in DNA methylation pattern related to BC incidence.

5.
Proc Natl Acad Sci U S A ; 117(14): 8013-8021, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32193335

RESUMO

AMP-activated protein kinase (AMPK) functions as an energy sensor and is pivotal in maintaining cellular metabolic homeostasis. Numerous studies have shown that down-regulation of AMPK kinase activity or protein stability not only lead to abnormality of metabolism but also contribute to tumor development. However, whether transcription regulation of AMPK plays a critical role in cancer metastasis remains unknown. In this study, we demonstrate that AMPKα1 expression is down-regulated in advanced human breast cancer and is associated with poor clinical outcomes. Transcription of AMPKα1 is inhibited on activation of PI3K and HER2 through ΔNp63α. Ablation of AMPKα1 expression or inhibition of AMPK kinase activity leads to disruption of E-cadherin-mediated cell-cell adhesion in vitro and increased tumor metastasis in vivo. Furthermore, restoration of AMPKα1 expression significantly rescues PI3K/HER2-induced disruption of cell-cell adhesion, cell invasion, and cancer metastasis. Together, these results demonstrate that the transcription control is another layer of AMPK regulation and suggest a critical role for AMPK in regulating cell-cell adhesion and cancer metastasis.


Assuntos
Proteínas Quinases Ativadas por AMP/genética , Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Animais , Mama/patologia , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Adesão Celular/efeitos dos fármacos , Adesão Celular/genética , Linhagem Celular Tumoral , Cromonas/farmacologia , Intervalo Livre de Doença , Regulação para Baixo , Feminino , Técnicas de Silenciamento de Genes , Humanos , Lapatinib/farmacologia , Camundongos , Morfolinas/farmacologia , Estadiamento de Neoplasias , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Prognóstico , Receptor ErbB-2/antagonistas & inibidores , Receptor ErbB-2/metabolismo , Análise Serial de Tecidos , Transcrição Gênica/efeitos dos fármacos , Ativação Transcricional , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Int J Mol Sci ; 20(5)2019 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30866414

RESUMO

Cell⁻cell adhesion plays an important role in regulation of cell proliferation, migration, survival, and drug sensitivity. Metformin, a first line drug for type 2 diabetes, has been shown to possess anti-cancer activities. However, whether cell⁻cell adhesion affects metformin anti-cancer activity is unknown. In this study, Microscopic and FACS analyses showed that metformin induced cancer cell⁻cell adhesion exemplified by cell aggregation and anoikis under glucose restriction. Furthermore, western blot and QPCR analyses revealed that metformin dramatically upregulated integrin ß1 expression. Silencing of integrin ß1 significantly disrupted cell aggregation and reduced anoikis induced by metformin. Moreover, we showed that p53 family member ΔNp63α transcriptionally suppressed integrin ß1 expression and is responsible for metformin-mediated upregulation of integrin ß1. In summary, this study reveals a novel mechanism for metformin anticancer activity and demonstrates that cell⁻cell adhesion mediated by integrin ß1 plays a critical role in metformin-induced anoikis.


Assuntos
Glucose/farmacologia , Integrina beta1/genética , Integrina beta1/metabolismo , Metformina/farmacologia , Neoplasias/metabolismo , Anoikis , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inativação Gênica , Células HEK293 , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Regulação para Cima
7.
J Cancer ; 8(13): 2636-2642, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28900501

RESUMO

Vincristine is extensively used chemotherapeutic medicine to treat leukemia. However, it remains a critical clinical problem with regard to its toxicity and drug-resistance. AMP-activated protein kinase (AMPK) is an energy sensor that is pivotal in maintaining cell metabolic homeostasis. It is reported that AMPK is involved in vincristine-induced apoptosis. However, whether AMPK is involved in chemotherapy-resistance is largely unclear. It is well-documented that metformin, a widely used medicine to treat type II diabetes, possesses anti-cancer activities, yet whether metformin affects leukemia cell viability via vincristine is unknown. In this study, we showed that both AMPKα1 mRNA and phosphorylated AMPK protein levels were significantly decreased in clinical leukemia samples. We further demonstrated that metformin sensitized leukemia cells to vincristine-induced apoptosis in an AMPK-dependent manner. In addition, knockdown of AMPKα1 significantly reduced the effects of metformin on vincristine-induced apoptosis. Taken together, these results indicate that AMPK activation is critical in metformin effects on vincristine-induced apoptosis and suggest a putative strategy of a combination therapy using metformin and vincristine in treatment of leukemia.

8.
Carbohydr Polym ; 166: 358-364, 2017 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-28385243

RESUMO

The use of cellulase hydrolysis of straw to produce fermentable sugars has many application prospects. However, cellulase is very expensive, which hampers its industrial applications. To improve cellulase's catalytic activity and reduce the enzyme cost, magnetite carboxymethyl chitosan/calcium alginate - cellulase bioconjugate (MCCCB) was synthesized via an improved hydrothermal method, molecular self-assembly technology, physical absorption, embedding and covalent bonding. Its loading capacity was 3.95mg/mL, and the catalytic activity increased to 267.18%. We decreased the release rate, improved the reusability, and enhanced the stability of MCCCB. Corn stalk hydrolysis also greatly improved, and the overall yield of fermentable sugars increased by 698.26%. All of these results indicate that MCCCB could significantly improve the efficiency of cellulase, greatly reduce the cost of enzyme, and effectively promote the production of fermentable sugars.


Assuntos
Alginatos/química , Quitosana/análogos & derivados , Quitosana/química , Zea mays , Celulase , Ácido Glucurônico , Ácidos Hexurônicos , Hidrólise
9.
J Biol Chem ; 292(13): 5253-5261, 2017 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-28193839

RESUMO

The blood glucose modifier metformin is used to treat type II diabetes and has also been shown to possess anticancer activities. Recent studies indicate that glucose deprivation can greatly enhance metformin-mediated inhibition of cell viability, but the molecular mechanism involved in this inhibition is unclear. In this study, we report that, under glucose deprivation, metformin inhibited expression of ΔNp63α, a p53 family member involved in cell adhesion pathways, resulting in disruption of cell matrix adhesion and subsequent apoptosis in human squamous carcinoma cells. We further show that metformin promoted ΔNp63α protein instability independent of AMP-activated protein kinase and that WWP1, an E3 ligase of ΔNp63α, was involved in metformin-mediated down-regulation of ΔNp63α levels. In addition, we demonstrate that a combination of metformin and the glycolysis inhibitor 2-deoxy-d-glucose significantly inhibited ΔNp63α expression and also suppressed xenographic tumor growth in vivo In summary, this study reveals a new mechanism for metformin-mediated anticancer activity and suggests a new strategy for treating human squamous cell carcinoma.


Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Metformina/farmacologia , Fatores de Transcrição/antagonistas & inibidores , Proteínas Supressoras de Tumor/antagonistas & inibidores , Proteínas Quinases Ativadas por AMP , Animais , Antineoplásicos/farmacologia , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Desoxiglucose/farmacologia , Quimioterapia Combinada , Xenoenxertos , Humanos , Metformina/uso terapêutico , Camundongos , Estabilidade Proteica/efeitos dos fármacos
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