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1.
J Affect Disord ; 353: 90-98, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38452935

RESUMO

BACKGROUND: Reversion from mild cognitive impairment (MCI) to normal cognition (NC) is not uncommon and indicates a better cognitive trajectory. This study aims to identify predictors of MCI reversion and develop a predicting model. METHOD: A total of 391 MCI subjects (mean age = 74.3 years, female = 61 %) who had baseline data of magnetic resonance imaging, clinical, and neuropsychological measurements were followed for two years. Multivariate logistic analyses were used to identify the predictors of MCI reversion after adjusting for age and sex. A stepwise backward logistic regression model was used to construct a predictive nomogram for MCI reversion. The nomogram was validated by internal bootstrapping and in an independent cohort. RESULT: In the training cohort, the 2-year reversion rate was 19.95 %. Predictors associated with reversion to NC were higher education level (p = 0.004), absence of APOE4 allele (p = 0.001), larger brain volume (p < 0.005), better neuropsychological measurements performance (p < 0.001), higher glomerular filtration rate (p = 0.035), and lower mean arterial pressure (p = 0.060). The nomogram incorporating five predictors (education, hippocampus volume, the Alzheimer's Disease Assessment Scale-Cognitive score, the Rey Auditory Verbal Learning Test-immediate score, and mean arterial pressure) achieved good C-indexes of 0.892 (95 % confidence interval [CI], 0.859-0.926) and 0.806 (95 % CI, 0.709-0.902) for the training and validation cohort. LIMITATION: Observational duration is relatively short; The predicting model warrant further validation in larger samples. CONCLUSION: This prediction model could facilitate risk stratification and early management for the MCI population.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Feminino , Idoso , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/patologia , Cognição , Imageamento por Ressonância Magnética , Hipocampo/patologia , Testes Neuropsicológicos , Doença de Alzheimer/diagnóstico por imagem , Progressão da Doença
2.
Molecules ; 28(17)2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37687154

RESUMO

With the overuse and misuse of antimicrobial drugs, antibacterial resistance is becoming a critical global health problem. New antibacterial agents are effective measures for overcoming the crisis of drug resistance. In this paper, a novel set of ciprofloxacin-indole/acetophenone hybrids was designed, synthesized, and structurally elucidated with the help of NMR and high-resolution mass spectrometry. The in vitro antibacterial activities of these hybrids against gram-positive and gram-negative pathogens, including four multidrug-resistant clinical isolates, were evaluated and compared with those of the parent drug ciprofloxacin (CIP). All the target compounds (MIC = 0.0625-32 µg/mL) exhibited excellent inhibitory activity against the strains tested. Among them, 3a (MIC = 0.25-8 µg/mL) showed comparable or slightly less potent activity than CIP. The most active hybrid, 8b (MIC = 0.0626-1 µg/mL), showed equal or higher activity than CIP. Moreover, compound 8b showed superior bactericidal capability to CIP, with undetectably low resistance frequencies. Furthermore, molecular docking studies conducted showed that 8b and CIP had a similar binding mode to DNA gyrase (Staphylocouccus aureus). Thus, hybrids 3a and 8b could act as a platform for further investigations.


Assuntos
Antibacterianos , Ciprofloxacina , Ciprofloxacina/farmacologia , Simulação de Acoplamento Molecular , Antibacterianos/farmacologia , DNA Girase , Indóis/farmacologia
3.
Cancer Cell ; 41(6): 1118-1133.e12, 2023 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-37267951

RESUMO

Cyclic GMP-AMP synthase (cGAS) is the major sensor for cytosolic DNA and activates type I interferon signaling and plays an essential role in antitumor immunity. However, it remains unclear whether the cGAS-mediated antitumor activity is affected by nutrient status. Here, our study reports that methionine deprivation enhances cGAS activity by blocking its methylation, which is catalyzed by methyltransferase SUV39H1. We further show that methylation enhances the chromatin sequestration of cGAS in a UHRF1-dependent manner. Blocking cGAS methylation enhances cGAS-mediated antitumor immunity and suppresses colorectal tumorigenesis. Clinically, cGAS methylation in human cancers correlates with poor prognosis. Thus, our results indicate that nutrient stress promotes cGAS activation via reversible methylation, and suggest a potential therapeutic strategy for targeting cGAS methylation in cancer treatment.


Assuntos
Cromatina , Metionina , Humanos , Cromatina/genética , Metionina/genética , Nucleotidiltransferases/genética , Nucleotidiltransferases/metabolismo , DNA , Imunidade Inata , Desmetilação , Proteínas Estimuladoras de Ligação a CCAAT/genética , Ubiquitina-Proteína Ligases/genética
4.
Cancers (Basel) ; 15(6)2023 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-36980604

RESUMO

This study aimed to construct an effective nomogram based on the clinical and oxidative stress-related characteristics to predict the prognosis of stage I lung adenocarcinoma (LUAD). A retrospective study was performed on 955 eligible patients with stage I LUAD after surgery at our hospital. The relationship between systematic-oxidative-stress biomarkers and the prognosis was analyzed. The systematic oxidative stress score (SOS) was established based on three biochemical indicators, including serum creatinine (CRE), lactate dehydrogenase (LDH), and uric acid (UA). SOS was an independent prognostic factor for stage I LUADs, and the nomogram based on SOS and clinical characteristics could accurately predict the prognosis of these patients. The nomogram had a high concordance index (C-index) (0.684, 95% CI, 0.656-0.712), and the calibration curves for recurrence-free survival (RFS) probabilities showed a strong agreement between the nomogram prediction and actual observation. Additionally, the patients were divided into two groups according to the cut-off value of risk points based on the nomogram, and a significant difference in RFS was observed between the high-risk and low-risk groups (p < 0.0001). SOS is an independent prognostic indicator for stage I LUAD. These things considered, the constructed nomogram based on SOS could accurately predict the survival of those patients.

5.
Nat Metab ; 5(2): 265-276, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36732624

RESUMO

The mechanistic target of rapamycin complex 1 (mTORC1) controls cell growth in response to amino acid and glucose levels. However, how mTORC1 senses glucose availability to regulate various downstream signalling pathways remains largely elusive. Here we report that AMP-activated protein kinase (AMPK)-mediated phosphorylation of WDR24, a core component of the GATOR2 complex, has a role in the glucose-sensing capability of mTORC1. Mechanistically, glucose deprivation activates AMPK, which directly phosphorylates WDR24 on S155, subsequently disrupting the integrity of the GATOR2 complex to suppress mTORC1 activation. Phosphomimetic Wdr24S155D knock-in mice exhibit early embryonic lethality and reduced mTORC1 activity. On the other hand, compared to wild-type littermates, phospho-deficient Wdr24S155A knock-in mice are more resistant to fasting and display elevated mTORC1 activity. Our findings reveal that AMPK-mediated phosphorylation of WDR24 modulates glucose-induced mTORC1 activation, thereby providing a rationale for targeting AMPK-WDR24 signalling to fine-tune mTORC1 activation as a potential therapeutic means to combat human diseases with aberrant activation of mTORC1 signalling including cancer.


Assuntos
Proteínas Quinases Ativadas por AMP , Alvo Mecanístico do Complexo 1 de Rapamicina , Complexos Multiproteicos , Serina-Treonina Quinases TOR , Animais , Humanos , Camundongos , Proteínas Quinases Ativadas por AMP/metabolismo , Glucose , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Complexos Multiproteicos/metabolismo , Fosforilação , Serina-Treonina Quinases TOR/metabolismo
6.
Mol Cell ; 83(1): 74-89.e9, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36528027

RESUMO

The GATOR2-GATOR1 signaling axis is essential for amino-acid-dependent mTORC1 activation. However, the molecular function of the GATOR2 complex remains unknown. Here, we report that disruption of the Ring domains of Mios, WDR24, or WDR59 completely impedes amino-acid-mediated mTORC1 activation. Mechanistically, via interacting with Ring domains of WDR59 and WDR24, the Ring domain of Mios acts as a hub to maintain GATOR2 integrity, disruption of which leads to self-ubiquitination of WDR24. Physiologically, leucine stimulation dissociates Sestrin2 from the Ring domain of WDR24 and confers its availability to UBE2D3 and subsequent ubiquitination of NPRL2, contributing to GATOR2-mediated GATOR1 inactivation. As such, WDR24 ablation or Ring deletion prevents mTORC1 activation, leading to severe growth defects and embryonic lethality at E10.5 in mice. Hence, our findings demonstrate that Ring domains are essential for GATOR2 to transmit amino acid availability to mTORC1 and further reveal the essentiality of nutrient sensing during embryonic development.


Assuntos
Complexos Multiproteicos , Serina-Treonina Quinases TOR , Animais , Camundongos , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Complexos Multiproteicos/genética , Complexos Multiproteicos/metabolismo , Proteínas Nucleares/metabolismo , Transdução de Sinais
7.
Front Nutr ; 9: 993425, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36466397

RESUMO

Background: Telomere length, which is related to chronic diseases and premature mortality, is influenced by dietary factors. Zinc is known as a dietary antioxidant micronutrient, however, its impact on telomere length remains unclear. Objective: We aimed to examine the potential effect of dietary zinc intake on telomere length among middle-aged and older individuals in the US. Materials and methods: Our study included 3,793 US participants aged 45 years and older from the 1999 to 2002 National Health and Nutrition Examination Survey (NHANES). 24-h dietary recall interviews were employed to evaluate zinc consumption. Leukocyte telomere length was assessed by real-time quantitative polymerase chain reaction (qPCR). We adopted generalized linear models to investigate the effect of dietary zinc intake on telomere length, and subgroup analyses were further applied. We further evaluated the dose-response relationship using restricted cubic spline analysis. Results: Among the 3,793 participants, the average telomere length was 0.926 ± 0.205 (T/S ratio) or 5509.5 ± 494.9 (bp). After adjusting for major confounders, every 5 mg increment in dietary zinc consumption was related to 0.64% (95% CI: 0.17%, 1.10%) longer telomere length. In the subgroup analyses, significant relationships were found in females (Percentage change: 1.11%; 95% CI: 0.48%, 1.75%), obese (Percentage change: 0.88%; 95% CI: 0.26%, 1.50%), and low energy intake individuals (Percentage change: 0.99%; 95% CI: 0.51%, 1.46%). Additionally, we revealed a positive linear relationship between dietary zinc intake and telomere length (P for non-linearity = 0.636). Conclusion: Our study revealed that elevated dietary zinc intake was significantly related to longer telomere length among adults aged 45 years and older in the US. And the association was more pronounced in females, obese, and low energy intake individuals.

8.
Front Surg ; 9: 987075, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36157427

RESUMO

Objective: The prognostic effect of delayed treatment on stage IA1 non-small cell lung cancer (NSCLC) patients is still unclear. This study aimed to explore the association between the waiting time before treatment and the prognosis in stage IA1 NSCLC patients. Methods: Eligible patients diagnosed with pathological stage IA1 NSCLC were included in this study. The clinical endpoints were overall survival (OS) and cancer-specific survival (CSS). The Kaplan-Meier method, the Log-rank test, univariable, and multivariable Cox regression analyses were used in this study. Propensity score matching was used to reduce the bias of data distribution. Results: There were eligible 957 patients in the study. The length of waiting time before treatment stratified the survival in patients [<3 months vs. ≥3-months, unadjusted hazard ratio (HR) = 0.481, P = 0.007; <2 months vs. ≥2-months, unadjusted HR = 0.564, P = 0.006; <1 month vs. ≥1-month, unadjusted HR = 0.537, P = 0.001]. The 5-year CSS rates were 95.0% and 77.0% in patients of waiting time within 3 months and over 3 months, respectively. After adjusting for other confounders, the waiting time was identified as an independent prognostic factor. Conclusions: A long waiting time before treatment may decrease the survival of stage IA1 NSCLC patients. We propose that the waiting time for those patients preferably is less than one month and should not exceed two months.

9.
Opt Express ; 29(22): 36111-36120, 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34809030

RESUMO

Capturing polarization information has long been an important topic in the field of detection. In this study, two polarization-dependent broadband absorbers based on a composite metamaterial structure were designed and numerically investigated. Unlike in conventional metamaterial absorbers, the bottom metallic film is functionalized to achieve a polarization response or broadband absorption. The simulation results show that the type I absorber exhibits TM polarization-dependent broadband absorption (absorptivity>80%) from 8.37 µm to 12.12 µm. In contrast, the type II absorber presents TE polarization-dependent broadband absorption (absorptivity>80%) from 8.23 µm to 11.93 µm. These devices are extremely sensitive to the change of polarization angle. The absorptivity changes monotonically with an increase of the polarization angle, but it is insensitive to oblique incidence. This design paves the way for realizing broadband polarization-dependent absorption via a simple configuration. It has bright prospects in thermal detection applications and imaging fields.

10.
J Mater Chem B ; 8(5): 1040-1048, 2020 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-31939980

RESUMO

By means of a simple and photo-induced method, four colors of molybdenum oxide quantum dots (MoOx QDs) have been synthesized, using Mo(CO)6 as the structural guiding agent and molybdenum source. The as-prepared MoOx QDs display diverse optical properties due to the different configurations of oxygen vacancies in various nanostructures. Among them, crystalline molybdenum dioxide (MoO2) with a deep blue color shows the most intense localized surface plasmon resonance effect in the near-infrared (NIR) region. The strong NIR absorption endows MoO2 QDs with a high photothermal conversion efficiency of 66.3%, enabling broad prospects as a photo-responsive nanoagent for photothermal therapy of cancer. Moreover, MoO2 QDs can also serve as a novel semiconductor substrate for ultrasensitive surface-enhanced Raman scattering (SERS) analysis of aromatic molecules, amino acids and antibiotics, with SERS performance comparable to that of noble metal-based substrates. The therapeutic applications of MoO2 QDs open up a new avenue for tumor nanomedicine.


Assuntos
Molibdênio/farmacologia , Óxidos/farmacologia , Terapia Fototérmica , Pontos Quânticos/química , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Hep G2 , Humanos , Teste de Materiais , Molibdênio/química , Nanoestruturas/química , Óxidos/síntese química , Óxidos/química , Tamanho da Partícula , Processos Fotoquímicos , Análise Espectral Raman , Propriedades de Superfície , Temperatura , Células Tumorais Cultivadas
11.
Nanoscale ; 12(3): 2133-2141, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31913376

RESUMO

Carcinoma-associated fibroblasts (CAFs), one of the most important components of a tumor microenvironment (TME), play a significant role in the complex tumorigenesis process. Herein, the evolution of CAFs in TME is elaborately investigated by surface-enhanced Raman spectroscopy (SERS), a molecular fingerprint technique. Two-dimensional (2D) nanocomposites consisting of gold nanoparticles and a supramolecular "PCsheet" self-assembled between 2D nanosheets and oxidized phosphatidylcholine (PC) are fabricated as SERS-active probes to specifically recognize the CD36 receptor on the cytomembrane of the fibroblasts, a reliable landmark of CAF development. The 2D SERS substrates can also illuminate the fingerprint information around the CD36 protein with high detection sensitivity, which helps elucidate the biochemical component transition in the protein mini-domain during carcinoma progression. Visualized data are then supplied by label-free SERS imaging to exploit the distribution of biomolecules on the plasma membrane. In addition, the repressed expression of CD36 in TME is detected in lung metastasis tumor-bearing mice. This study based on the 2D SERS technique opens up an alternative avenue for unveiling carcinoma-associated molecular events.


Assuntos
Fibroblastos/metabolismo , Ouro , Neoplasias Pulmonares , Nanopartículas Metálicas , Nanocompostos , Microambiente Tumoral , Animais , Fibroblastos/patologia , Ouro/química , Ouro/farmacologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Camundongos , Células NIH 3T3 , Nanocompostos/química , Nanocompostos/uso terapêutico , Metástase Neoplásica
12.
Biotechnol Lett ; 42(1): 135-142, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31734772

RESUMO

OBJECTIVES: To characterize a glycosyltransferase (UGT74AN3) from Catharanthus roseus and investigate its specificity toward cardiotonic steroids and phenolic compounds. RESULTS: UGT74AN3, a novel permissive GT from C. roseus, displayed average high conversion rate (> 90%) toward eight structurally different cardiotonic steroids. Among them, resibufogenin, digitoxigenin, and uzarigenin gave 100% yield. Based on LC-MS, 1H-NMR and 13C-NMR analysis, structure elucidation of eight glycosides was consistent with 3-O-ß-D-glucosides. We further confirmed UGT74AN3 was permissive enough to glycosylate curcumin, resveratrol, and phloretin. The cDNA sequence of UGT74AN3 contained an ORF of 1,425 nucleotides encoding 474 amino acids. UGT74AN3 performed the maximum catalytic activity at 40 °C, pH 8.0, and was divalent cation-independent. Km values of UGT74AN3 toward resibufogenin, digitoxigenin, and uzarigenin were 7.0 µM, 12.3 µM, and 17.4 µM, respectively. CONCLUSIONS: UGT74AN3, a glycosyltransferase from a noncardenolide-producing plant, displayed catalytic efficiency toward cardiotonic steroids and phenolic compounds, which would make it feasible for glycosylation of bioactive molecules.


Assuntos
Antiarrítmicos/metabolismo , Glicosídeos Cardíacos/metabolismo , Catharanthus/enzimologia , Glicosiltransferases/metabolismo , Fenóis/metabolismo , Biotransformação , Catharanthus/genética , Cromatografia Líquida , Clonagem Molecular , Inibidores Enzimáticos , Estabilidade Enzimática , Glicosilação , Glicosiltransferases/genética , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Especificidade por Substrato , Temperatura
13.
Psychol Res Behav Manag ; 12: 913-929, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31576184

RESUMO

PURPOSE: This study aims to explore consumers' implicit motivations for purchasing luxury brands based on the functional theories of attitudes by using event-related potentials (ERPs). METHODS: Brand authenticity and logo prominence were used to modulate the social-adjustive function and value-expressive function, respectively. Twenty right-handed healthy female undergraduates and graduates participated in an experiment that has a 2 brand authenticity (genuine/counterfeit) × 2 brand prominence (prominent logo/no logo) design. In the experiment, participators browsed different luxury handbags with different brand authenticity and logo prominence, and then reported their purchase intentions on a five-point scale. Meanwhile, EEGs were recorded from the subjects throughout the experiment. In the analysis process, three ERP components, which can, respectively, reflect the cognitive conflict (N200), emotional conflict (N400) and motivational emotional arousal (LPP) during the evaluation of marketing-related stimuli, were mainly focused. RESULTS: For counterfeit brands, the no logo condition elicited significant larger N200 amplitude, marginally significant larger N400 amplitude and significant smaller LPP amplitude than the prominent logo condition. However, for genuine brands, this modulation effect of logo prominence cannot be found. These results imply that consumers' implicit social motivations for purchasing luxury brands come from the satisfaction of at least one social goal. When one goal cannot be satisfied, consumers will more expect the satisfaction of another one. If this expectation is violated, it seems to be unexpected and unacceptable. Thus, greater anticipation conflict (N200) and emotion conflict (N400) will be induced, and the purchase motivation (LPP) cannot be aroused. CONCLUSION: Consumers' preferences for luxury brands are based on the satisfaction of their social goals. These social goals always coexist and perform as compensation with each other. The dissatisfaction of one social goal would promote their expectation of the satisfaction of another social goal.

14.
Analyst ; 144(14): 4312-4319, 2019 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-31188363

RESUMO

A deep learning network called "residual neural network" (ResNet) was used to decode Raman spectra-encoded suspension arrays (SAs). With narrow bandwidths and stable signals, Raman spectra have ideal encoding properties. The different Raman reporter molecules assembled micro-quartz pieces (MQPs) were grafted with various biomolecule probes, which enabled simultaneous detection of numerous target analytes in a single sample. Multiple types of mixed MQPs were measured by Raman spectroscopy and then decoded by ResNet to acquire the type information of analytes. The good classification performance of ResNet was verified by a t-distributed stochastic neighbor embedding (t-SNE) diagram. Compared with other machine learning models, these experiments showed that ResNet was obviously superior in terms of classification stability and training convergence to different datasets. This method simplified the decoding process and the classification accuracy reached 100%.

15.
Front Hum Neurosci ; 12: 417, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30369874

RESUMO

Nowadays, the international community is becoming increasingly concerned about the sustainable utilization of natural resources. In order to protect the environment and reward sustainable practices, eco-labeling that signifies the environmental friendliness of the labeled food is already widely promoted in many regions around the world. Thus, it is of great importance for researchers to study consumers' attitudes toward eco-labeled food as food is supposed to satisfy consumers' needs. This study employed the event-related potentials (ERPs) approach to investigate consumers' attitudes toward eco-labeled food by comparing their neural processing of visual stimuli depicting eco-labeled and non-labeled food. Our results showed that behaviorally, participants preferred to buy eco-labeled food rather than non-labeled one. At the neural level, we observed markedly smaller P2 and N2 amplitudes when pictures of eco-labeled food were presented. Furthermore, we also found that amplitudes of P2 were negatively correlated with participants' purchase intention. Therefore, our current findings suggest that, while the environmental-friendly eco-labeling was not to one's own interests, it might still be evocative, which induce consumers' positive emotion, bring less cognitive conflict to the purchase decision-making and then result in a greater purchasing intention. This effect might be the result of the delivered value of social desirability.

16.
Neurosci Lett ; 681: 1-5, 2018 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-29772258

RESUMO

As herding is a typical characteristic of human behavior, many researchers have found the existence of herding behavior in online peer-to-peer lending through empirical surveys. However, the underlying neural basis of this phenomenon is still unclear. In the current study, we studied the neural activities of herding at decision-making stage and feedback stage using event-related potentials (ERPs). Our results showed that at decision-making stage, larger error related negativity (ERN) amplitude was induced under low-proportion conditions than that of high-proportion conditions. Meanwhile, during feedback stage, negative feedback elicited larger feedback related negativity (FRN) amplitude than that of positive feedback under low-proportion conditions, however, there was no significant FRN difference under high-proportion conditions. The current study suggests that herding behavior in online peer-to-peer lending is related to individual's risk perception and is possible to avoid negative emotions brought by failed investments.


Assuntos
Tomada de Decisões/fisiologia , Potenciais Evocados Visuais/fisiologia , Retroalimentação Psicológica/fisiologia , Administração Financeira , Grupo Associado , Adolescente , Adulto , Eletroencefalografia/métodos , Feminino , Administração Financeira/métodos , Humanos , Masculino , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Adulto Jovem
17.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 33(9): 1234-1239, 2017 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-29089083

RESUMO

Objective To observe the effect of metadherin/astrocyte elevated gene-1 (MTDH/AEG-1) silencing on the proliferation and metastasis of SGC7901 human gastric cancer cells. Methods The eukaryotic shRNA expression vectors targeting MTDH gene were constructed and transfected into SGC7901 cells. Effects of gene silencing were confirmed by Western blotting. MTT assay was used to detect the effect of MTDH on the proliferation of SGC7901 cells, and TranswellTM assay was employed to detect the effect of MTDH on the migration of SGC7901 cells. Results MTDH-shRNA was constructed and transfected into SGC-7901 cells successfully. After transfection, the level of MTDH protein expression was reduced significantly. Knockdown of MTDH in SGC7901 cells, the abilities of cell proliferation and migration decreased obviously. Conclusion Knockdown of MTDH gene effectively inhibits the proliferation and metastasis of SGC7901 cells.


Assuntos
Moléculas de Adesão Celular/fisiologia , Neoplasias Gástricas/patologia , Moléculas de Adesão Celular/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Humanos , Proteínas de Membrana , Invasividade Neoplásica , RNA Interferente Pequeno/genética , Proteínas de Ligação a RNA
18.
Mol Med Rep ; 12(2): 3047-54, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25976311

RESUMO

Gastric cancer is one of the most common types of cancer worldwide. It has been reported that stromal interacting molecule 1 (STIM1) is associated with tumor progression and metastatic spread, including in cervical cancer, breast carcinoma and prostatic cancer. The present study investigated whether STIM1, an endoplasmic reticulum Ca(2+) sensor and activator of store-operated channel entry, contributed to SGC7901 cell progression. The pGPU6-shSTIM1 recombinant plasmid was constructed, and the effects of downregulation of STIM1 on the proliferation, apoptosis, migration and invasion of SGC7901 cells were examined. Western blot analysis revealed that transfection with the pGPU6-shSTIM1 plasmid successfully inhibited the expression of STIM1. STIM1 silencing in the gastric cancer cells significantly inhibited cell proliferation by arresting the cell cycle at the G0/G1 phase, and increasing the apoptotic rate following treatment of the SGC7901 cells with pGPU6-shSTIM1, indicated using an MTT cell viability assay and flow cytometery, respectively. As expected, STIM1 knock down also reduced the migration and invasion of the SGC7901 cells, demonstrated using a Transwell assay. The possible molecular mechanism involved the regulation of several signaling pathways involved in the biological behavior of cell survival, apoptosis, migration and metastasis. Together, these finding suggested that the expression of STIM1 is crucial for the proliferation and invasion of SGC7901 cells, providing a foundation for the development of novel type­specific diagnostic strategies and treatments for gastric cancer.


Assuntos
Proteínas de Membrana/metabolismo , Proteínas de Neoplasias/metabolismo , RNA Interferente Pequeno/metabolismo , Apoptose , Cálcio/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Pontos de Checagem da Fase G1 do Ciclo Celular , Humanos , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/genética , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Interferência de RNA , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Molécula 1 de Interação Estromal , Transfecção
19.
Oncol Rep ; 31(3): 1489-97, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24398929

RESUMO

Peritoneal metastasis is a major cause of death in patients with advanced gastric carcinoma. DJ-1 is now considered to play an important role in the metastasis of various malignancies. However, it remains largely unclear whether DJ-1 is involved in the development of peritoneal metastasis by gastric carcinoma. In the present study, we showed that the expression of DJ-1 was significantly upregulated in gastric cancer specimens with peritoneal metastasis compared to those without peritoneal metastasis. Knockdown of DJ-1 expression significantly inhibited invasion and migration, in vitro and the in vivo peritoneal metastatic abilities of SGC7901 gastric cancer cells. Moreover, knockdown of DJ-1 also diminished the expression of matrix metallopeptidase (MMP)-2 and MMP-9. All of these effects were reversed by restoration of DJ-1 expression. Following investigation of the pathway through which DJ-1 regulates cell invasion and migration, DJ-1 was found to cause phosphorylation of Akt in SGC7901 gastric cancer cells. Inhibition of the Akt pathway in SGC7901 cells mimicked the effects of DJ-1 knockdown on cell migration, invasion, MMP-2 and MMP-9 expression, and abolished the effects of DJ-1 in promoting SGC7901 cell invasion and migration. Taken together, the present study revealed that DJ-1 plays an important role in the development of peritoneal carcinomatosis from gastric carcinoma, at least partially through activation of the Akt pathway and consequent upregulation of MMP-2 and MMP-9 expression. Thus, DJ-1 may be a potential therapeutic target for peritoneal carcinomatosis of gastric carcinoma.


Assuntos
Adenocarcinoma/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Oncogênicas/metabolismo , Neoplasias Peritoneais/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neoplasias Gástricas/metabolismo , Adenocarcinoma/secundário , Animais , Linhagem Celular Tumoral , Movimento Celular , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Invasividade Neoplásica , Transplante de Neoplasias , Neoplasias Peritoneais/secundário , Proteína Desglicase DJ-1 , Transdução de Sinais , Neoplasias Gástricas/patologia , Regulação para Cima
20.
Mol Cell Biochem ; 385(1-2): 33-41, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24048861

RESUMO

It has been well demonstrated that hypoxic preconditioning (HPC) can attenuate hypoxia/reoxygenation (H/R)-induced oxidant stress and elicit delayed cardioprotection by upregulating the expression of multiple antioxidative enzymes such as heme oxygenase-1 (HO-1), manganese superoxide dismutase (MnSOD) and so on. However, the underlying mechanisms of HPC-induced upregulation of antioxidative enzymes are not fully understood. Nuclear factor erythroid 2-related factor 2 (Nrf2) is an essential transcription factor that regulates expression of several antioxidant genes via binding to the antioxidant response element (ARE) and plays a crucial role in cellular defence against oxidative stress. Here, we wondered whether activation of the Nrf2-ARE pathway is responsible for the induction of antioxidative enzymes by HPC and contributes to the delayed cardioprotection of HPC. Cellular model of HPC from rat heart-derived H9c2 cells was induced 24 h prior to H/R. The results showed that HPC efficiently attenuated H/R-induced viability loss and lactate dehydrogenase leakage. In addition, HPC increased nuclear translocation and ARE binding of Nrf2 during the late phase, upregulated the expression of antioxidative enzymes (HO-1 and MnSOD), inhibited H/R-induced oxidant stress. However, when Nrf2 was specifically knocked down by siRNA, the induction of antioxidative enzymes by HPC was completely abolished and, as a result, the inhibitory effect of HPC on H/R-induced oxidant stress was reversed, and the delayed cardioprotection induced by HPC was also abolished. These results suggest that HPC upregulates antioxidative enzymes through activating the Nrf2-ARE pathway and confers delayed cardioprotection against H/R-induced oxidative stress.


Assuntos
Antioxidantes/metabolismo , Cardiotônicos/metabolismo , Precondicionamento Isquêmico Miocárdico , Miócitos Cardíacos/enzimologia , Miócitos Cardíacos/patologia , Fator 2 Relacionado a NF-E2/metabolismo , Regulação para Cima , Animais , Elementos de Resposta Antioxidante/genética , Hipóxia Celular , Linhagem Celular , Núcleo Celular/metabolismo , Técnicas de Silenciamento de Genes , Ligação Proteica , Transporte Proteico , Ratos , Transdução de Sinais , Estresse Fisiológico
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