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1.
Biomolecules ; 14(6)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38927027

RESUMO

Microbiota tryptophan metabolism and the biosynthesis of indole derivatives play an important role in homeostasis and pathogenesis in the human body and can be affected by the gut microbiota. However, studies on the interplay between gut microbiota and tryptophan metabolites in patients undergoing dialysis are lacking. This study aimed to identify the gut microbiota, the indole pathway in tryptophan metabolism, and significant functional differences in ESRD patients with regular hemodialysis. We performed the shotgun metagenome sequencing of stool samples from 85 hemodialysis patients. Using the linear discriminant analysis effect size (LEfSe), we examined the composition of the gut microbiota and metabolic features across varying concentrations of tryptophan and indole metabolites. Higher tryptophan levels promoted tyrosine degradation I and pectin degradation I metabolic modules; lower tryptophan levels were associated with glutamate degradation I, fructose degradation, and valine degradation modules. Higher 3-indoxyl sulfate concentrations were characterized by alanine degradation I, anaerobic fatty acid beta-oxidation, sulfate reduction, and acetyl-CoA to crotonyl-CoA. Contrarily, lower 3-indoxyl sulfate levels were related to propionate production III, arabinoxylan degradation, the Entner-Doudoroff pathway, and glutamate degradation II. The present study provides a better understanding of the interaction between tryptophan, indole metabolites, and the gut microbiota as well as their gut metabolic modules in ESRD patients with regular hemodialysis.


Assuntos
Microbioma Gastrointestinal , Indóis , Diálise Renal , Triptofano , Humanos , Triptofano/metabolismo , Indóis/metabolismo , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Falência Renal Crônica/terapia , Falência Renal Crônica/metabolismo , Falência Renal Crônica/microbiologia , Fezes/microbiologia , Redes e Vias Metabólicas , Adulto , Metagenoma
2.
Nutrients ; 15(5)2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36904261

RESUMO

Predictors of healthy eating parameters, including the Healthy Eating Index (HEI), Glycemic Index (GI), and Glycemic Load (GL), were examined using various modern diets (n = 131) in preparation for personalized nutrition in the e-health era. Using Nutrition Data Systems for Research computerized software and artificial intelligence machine-learning-based predictive validation analyses, we included domains of HEI, caloric source, and various diets as the potentially modifiable factors. HEI predictors included whole fruits and whole grains, and empty calories. Carbohydrates were the common predictor for both GI and GL, with total fruits and Mexican diets being additional predictors for GI. The median amount of carbohydrates to reach an acceptable GL < 20 was predicted as 33.95 g per meal (median: 3.59 meals daily) with a regression coefficient of 37.33 across all daily diets. Diets with greater carbohydrates and more meals needed to reach acceptable GL < 20 included smoothies, convenient diets, and liquids. Mexican diets were the common predictor for GI and carbohydrates per meal to reach acceptable GL < 20; with smoothies (12.04), high-school (5.75), fast-food (4.48), Korean (4.30), Chinese (3.93), and liquid diets (3.71) presenting a higher median number of meals. These findings could be used to manage diets for various populations in the precision-based e-health era.


Assuntos
Carga Glicêmica , Telemedicina , Índice Glicêmico , Dieta Saudável , Inteligência Artificial , Dieta , Glicemia , Carboidratos da Dieta
3.
J Pers Med ; 12(5)2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35629083

RESUMO

Obesity with adiposity is a common disorder in modern days, influenced by environmental factors such as eating and lifestyle habits and affecting the epigenetics of adipose-based gene regulations and metabolic pathways in colorectal cancer (CRC). We compared epigenetic changes of differentially methylated regions (DMR) of genes in colon tissues of 225 colon cancer cases (154 non-obese and 71 obese) and 15 healthy non-obese controls by accessing The Cancer Genome Atlas (TCGA) data. We applied machine-learning-based analytics including generalized regression (GR) as a confirmatory validation model to identify the factors that could contribute to DMRs impacting colon cancer to enhance prediction accuracy. We found that age was a significant predictor in obese cancer patients, both alone (p = 0.003) and interacting with hypomethylated DMRs of ZBTB46, a tumor suppressor gene (p = 0.008). DMRs of three additional genes: HIST1H3I (p = 0.001), an oncogene with a hypomethylated DMR in the promoter region; SRGAP2C (p = 0.006), a tumor suppressor gene with a hypermethylated DMR in the promoter region; and NFATC4 (p = 0.006), an adipocyte differentiating oncogene with a hypermethylated DMR in an intron region, are also significant predictors of cancer in obese patients, independent of age. The genes affected by these DMR could be potential novel biomarkers of colon cancer in obese patients for cancer prevention and progression.

4.
Nutrients ; 14(3)2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35276892

RESUMO

In preparation for personalized nutrition, an accurate assessment of dietary intakes on key essential nutrients using smartphones can help promote health and reduce health risks across vulnerable populations. We, therefore, validated the accuracy of a mobile application (app) against Food Frequency Questionnaire (FFQ) using artificial intelligence (AI) machine-learning-based analytics, assessing key macro- and micro-nutrients across various modern diets. We first used Bland and Altman analysis to identify and visualize the differences between the two measures. We then applied AI-based analytics to enhance prediction accuracy, including generalized regression to identify factors that contributed to the differences between the two measures. The mobile app underestimated most macro- and micro-nutrients compared to FFQ (ranges: -5% for total calories, -19% for cobalamin, -33% for vitamin E). The average correlations between the two measures were 0.87 for macro-nutrients and 0.84 for micro-nutrients. Factors that contributed to the differences between the two measures using total calories as an example, included caloric range (1000-2000 versus others), carbohydrate, and protein; for cobalamin, included caloric range, protein, and Chinese diet. Future studies are needed to validate actual intakes and reporting of various diets, and to examine the accuracy of mobile App. Thus, a mobile app can be used to support personalized nutrition in the mHealth era, considering adjustments with sources that could contribute to the inaccurate estimates of nutrients.


Assuntos
Aplicativos Móveis , Telemedicina , Inteligência Artificial , Dieta , Promoção da Saúde , Nutrientes , Inquéritos e Questionários
5.
Turk J Gastroenterol ; 30(5): 415-419, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31060996

RESUMO

BACKGROUND/AIMS: Gastric cancer (GC) is one of the most common gastrointestinal malignancies. Many studies have demonstrated that serum microRNAs have potential applications as non-invasive biomarkers for cancer diagnosis. The aim of the present study was to investigate the expression of serum miR-551b-3p in patients with GC and to explore its potential as a diagnostic biomarker in GC. MATERIALS AND METHODS: The expression of miR-551b-3p was detected using quantitative reverse transcription polymerase chain reaction in preoperative serum samples of 50 patients with GC and 53 healthy individuals. An analysis was performed to determine the correlation between serum miR-551b-3p levels and clinicopathological characteristics of patients with GC. The receiver operating characteristic curve was generated, and the cut-off point of serum miR-551b-3p for the diagnosis of GC was selected. The clinical value of serum miR-551b-3p for GC was analyzed by a consistency test. RESULTS: The expression of serum miR-551b-3p was significantly lower in patients with GC than in healthy individuals (p=0.000). Low level was positively associated with tumor size (p=0.014), depth of invasion (p=0.001), and Tumor-Node-Metastasis stage (p=0.022). The area under the curve for serum miR-551b-3p distinguishing patients with GC from healthy individuals was 0.860 (95% CI: 0.787-0.933, p=0.000), with a specificity of 96.2% and a sensitivity of 70%. The kappa consistency test had a kappa value of 0.667 (p=0.000) in GC. CONCLUSION: Serum miR-551b-3p may potentially serve as a diagnostic biomarker for GC.


Assuntos
MicroRNAs/sangue , Neoplasias Gástricas/diagnóstico , Área Sob a Curva , Biomarcadores Tumorais/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Neoplasias Gástricas/sangue
6.
Toxics ; 6(3)2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30071659

RESUMO

The purpose of this updated meta-analysis was to investigate the effect of nitric oxide synthase-3 (NOS3) G894T polymorphisms, air pollution and their interaction on ischemic heart disease (IHD) risk across populations worldwide. Recursive partition trees, nonlinear association curve fit and geographic information system maps were incorporated to verify results of conventional pooled analyses for sources of heterogeneity. Results from 61 studies (16,219 cases, 12,222 controls) revealed a significant increased relative risk (RR) of IHD associated with NOS3 894 polymorphisms TT (RR = 1.44) and GT (RR = 1.37). Subgroup analysis revealed that the TT polymorphism genotype had significantly increased risk of IHD in Caucasian, East Asian, South Asian, and Middle Eastern populations (all p < 0.05). It is important to point out that many countries demonstrated an average risk of greater than two, which identifies the NOS3 894 TT polymorphism as a potential causal factor and biological marker of IHD, based on criteria for strong evidence used in international consensus panels. These 10 countries include Ukraine, the United Kingdom, Brazil, Chile, Japan, South Korea, India, Iran, Egypt and Morocco. For these countries with elevated risk (RR > 2) from the NOS3 894 TT polymorphism, meta-predictive analysis demonstrated an increasing trend in air pollution association with increased NOS3 894 polymorphisms. Further studies are needed to explore the complexity of the associations among NOS3 gene polymorphisms per population stratifications within countries, detailed air pollution data for added specificity for geographic location across time, and disease risk.

7.
Artigo em Inglês | MEDLINE | ID: mdl-29996520

RESUMO

Ischemic heart disease (IHD) is among the leading causes of death worldwide. Methylenetetrahydrofolate reductase (MTHFR) polymorphisms have been associated with IHD risk, but the findings presented with heterogeneity. The purpose of the present meta-analysis was to provide an updated evaluation by integrating machine-learning based analytics to examine the potential source of heterogeneity on the associations between MTHFR polymorphisms and the risk of various subtypes of IHD, as well as the possible impact of air pollution on MTHFR polymorphisms and IHD risks. A comprehensive search of various databases was conducted to locate 123 studies (29,697 cases and 31,028 controls) for MTHFR C677T, and 18 studies (7158 cases and 5482 controls) for MTHFR A1298C. Overall, MTHFR 677 polymorphisms were risks for IHD (TT: Risk ratio (RR) = 1.23, p < 0.0001; CT: RR = 1.04, p = 0.0028, and TT plus CT: RR = 1.09, p < 0.0001). In contrast, MTHFR 677 CC wildtype was protective against IHD (RR = 0.91, p < 0.00001) for overall populations. Three countries with elevated IHD risks from MTHFR C677T polymorphism with RR >2 included India, Turkey, and Tunisia. Meta-predictive analysis revealed that increased air pollution was associated with increased MTHFR 677 TT and CT polymorphisms in both the case and control group (p < 0.05), with the trend of increased IHD risk resulting from increased air pollution. These results associate the potential inflammatory pathway with air pollution and the folate pathway with MTHFR polymorphism. Future intervention studies can be designed to mitigate MTHFR enzyme deficiencies resulting from gene polymorphisms to prevent IHDs for at-risk populations.


Assuntos
Poluição do Ar/efeitos adversos , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Isquemia Miocárdica/genética , Estudos de Casos e Controles , Predisposição Genética para Doença , Humanos , Isquemia Miocárdica/epidemiologia , Razão de Chances , Polimorfismo Genético
8.
J Food Drug Anal ; 26(1): 221-231, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29389559

RESUMO

Human triple-negative breast cancer (TNBC) is the most aggressive and poorly understood subclass of breast cancer. Glucose transporters (GLUTs) are required for glucose uptake in malignant cancer cells and are ideal targets for cancer therapy. To determine whether the inhibition of GLUTs could be used in TNBC cell therapy, the apple polyphenol phloretin (Ph) was used as a specific antagonist of GLUT2 protein function in human TNBC cells. Interestingly, we found that Ph (10-150 µM, for 24 h) inhibited cell growth and arrested the cell cycle in MDA-MB-231 cells in a p53 mutant-dependent manner, which was confirmed by pre-treatment of the cells with a p53-specific dominant-negative expression vector. We also found that Ph treatment (10-150 µM, for 24 h) significantly decreased the migratory activity of the MDA-MB-231 cells through the inhibition of paxillin/FAK, Src, and alpha smooth muscle actin (α-sMA) and through the activation of E-cadherin. Furthermore, the anti-tumorigenic effect of Ph (10, 50 mg/kg or DMSO twice a week for six weeks) was demonstrated in vivo using BALB/c nude mice bearing MDA-MB-231 tumor xenografts. A decrease in N-cadherin, vimentin and an increase in p53, p21 and E-cadherin were detected in the tumor tissues. In conclusion, inhibition of GLUT2 by the apple polyphenol Ph could potentially suppress TNBC tumor cell growth and metastasis.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Movimento Celular/efeitos dos fármacos , Transportador de Glucose Tipo 2/metabolismo , Malus/química , Floretina/farmacologia , Extratos Vegetais/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Antineoplásicos Fitogênicos/química , Neoplasias da Mama/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Floretina/química , Extratos Vegetais/química , Ensaios Antitumorais Modelo de Xenoenxerto
9.
J Microbiol Immunol Infect ; 51(2): 278-285, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28711435

RESUMO

BACKGROUD/PURPOSE: Aggregatibacter actinomycetemcomitans has emerged as one of the aetiological agents in periodontal disease. Although Type IV secretion systems (T4SSs) are widely distributed in many bacteria, the genetic features and distribution of T4SSs in A. actinomycetemcomitans remain unclear. In this study, we investigated the prevalence of A. actinomycetemcomitans serotypes and their T4SSs in a Taiwanese population. METHODS: A comparative analysis of 20 A. actinomycetemcomitans genomes and their T4SSs deposited in GenBank was performed. One hundred subjects, including 20 periodontitis and 80 normal subjects, were enrolled and PCR identification of A. actinomycetemcomitans serotypes and T4SS genes were performed. RESULTS: Of 100 subjects, serotypes C (22%) and E (11%) were most common. In addition, T4SSs were distributed in all of the serotypes. The prevalence of T4SSs and their location in plasmids in periodontitis subjects were 1.28-2 fold higher but not significantly different compared to normal subjects. Of 20 A. actinomycetemcomitans genomes, only ten with complete T4SS modules could be detected, which was highly correlated with localized aggressive periodontitis (p < 0.1). Nine of ten T4SS modules were from periodontitis subjects. Phylogenetic analysis of 10 T4SSs in A. actinomycetemcomitans showed that they were clustered into two groups, T4SSAaI and T4SSAaII, with only T4SSAaI appearing in the Taiwanese subjects. CONCLUSION: A. actinomycetemcomitans strains with different serotypes carrying T4SSAaI are widely distributed in a Taiwanese population. This is the first report to show the distribution and detailed comparative genomics of T4SSs in A. actinomycetemcomitans.


Assuntos
Aggregatibacter actinomycetemcomitans/classificação , Aggregatibacter actinomycetemcomitans/genética , Placa Dentária/microbiologia , Infecções por Pasteurellaceae/epidemiologia , Doenças Periodontais/microbiologia , Sistemas de Secreção Tipo IV/genética , Aggregatibacter actinomycetemcomitans/metabolismo , Transporte Biológico/genética , Genoma Bacteriano/genética , Humanos , Infecções por Pasteurellaceae/microbiologia , Sorogrupo , Taiwan/epidemiologia
10.
Sci Rep ; 7(1): 8230, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28811583

RESUMO

Indoor microbial communities have important implications for human health, especially in health-care institutes (HCIs). The factors that determine the diversity and composition of microbiomes in a built environment remain unclear. Herein, we used 16S rRNA amplicon sequencing to investigate the relationships between building attributes and surface bacterial communities among four HCIs located in three buildings. We examined the surface bacterial communities and environmental parameters in the buildings supplied with different ventilation types and compared the results using a Dirichlet multinomial mixture (DMM)-based approach. A total of 203 samples from the four HCIs were analyzed. Four bacterial communities were grouped using the DMM-based approach, which were highly similar to those in the 4 HCIs. The α-diversity and ß-diversity in the naturally ventilated building were different from the conditioner-ventilated building. The bacterial source composition varied across each building. Nine genera were found as the core microbiota shared by all the areas, of which Acinetobacter, Enterobacter, Pseudomonas, and Staphylococcus are regarded as healthcare-associated pathogens (HAPs). The observed relationship between environmental parameters such as core microbiota and surface bacterial diversity suggests that we might manage indoor environments by creating new sanitation protocols, adjusting the ventilation design, and further understanding the transmission routes of HAPs.


Assuntos
Bactérias/classificação , Bactérias/genética , Biodiversidade , Microbiologia Ambiental , Instalações de Saúde , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Metagenômica/métodos , Microbiota , Filogenia , RNA Ribossômico 16S/genética , Taiwan/epidemiologia
11.
Artigo em Inglês | MEDLINE | ID: mdl-28085050

RESUMO

Background: Alzheimer's disease (AD) is a significant public health issue. AD has been linked with methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism, but the findings have been inconsistent. The purpose of this meta-predictive analysis is to examine the associations between MTHFR polymorphisms and epigenetic factors, including air pollution, with AD risk using big data analytics approaches. Methods and Results: Forty-three studies (44 groups) were identified by searching various databases. MTHFR C677T TT and CT genotypes had significant associations with AD risk in all racial populations (RR = 1.13, p = 0.0047; and RR = 1.12, p < 0.0001 respectively). Meta-predictive analysis showed significant increases of percentages of MTHFR C677T polymorphism with increased air pollution levels in both AD case group and control group (p = 0.0021-0.0457); with higher percentages of TT and CT genotypes in the AD case group than that in the control group with increased air pollution levels. Conclusions: The impact of MTHFR C677T polymorphism on susceptibility to AD was modified by level of air pollution. Future studies are needed to further examine the effects of gene-environment interactions including air pollution on AD risk for world populations.


Assuntos
Poluição do Ar/análise , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/genética , Interação Gene-Ambiente , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Predisposição Genética para Doença , Genótipo , Humanos , Polimorfismo Genético , Risco
12.
Asian Pac J Cancer Prev ; 16(5): 1781-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25773825

RESUMO

BACKGROUND: miRNAs are relatively recently discovered cancer biomarkers which have important implications for cancer early diagnosis, treatment and estimation of prognosis. Here we focussed on expression of mir-196a-5p in gastric cancer tissues and cell lines so as to analyse its significance for clinicopathologic characteristics and generate enriched KEGG pathways clustered by target genes for exploring its potential roles as a biomarker in gastric cancer. MATERIALS AND METHODS: The expression of mir-196a-5p in poorly, moderate and well differentiated gastric cancer cell lines compared with GES-1 was detected by RT-qPCR, and the expression of mir-196a-5p in gastric cancer tissues comparing with adjacent non cancer tissues of 58 cases were also assessed by RT- qPCR. Subsequently, an analysis of clinical significance of mir-196a-5p in gastric cancer and enriched KEGG pathways was executed based on the miRWalk prediction database combined with bioinformatics tools DAVID 6.7 and Mirfocus 3.0. RESULTS: RT-qPCR showed that mir-196a-5p was up-regulated in 6 poorly and moderate differentiated gastric cancer cell lines SGC-7901, MKN-45, MKN-28, MGC-803, BGC-823, HGC-27 compared with GES-1, but down-regulated in the highly differentiated gastric cancer cell line AGS. Clinical data indicated mir-196a-5p to beup-regulated in gastric cancer tissues (47/58). Overexpression of mir-196a-5p was associated with more extensive degree of lymph node metastasis and clinical stage (P <0.05; x2 test). Enriched KEGG pathway analyses of predicted and validated targets in miRWalk combined with DAVID 6.7 and Mirfocus 3.0 showed that the targeted genes regulated by mir-196a-5p were involved in malignancy associated biology. CONCLUSIONS: Overexpression of mir-196a-5p is associated with lymph node metastasis and clinical stage, and enriched KEGG pathway analyses showed that targeted genes regulated by mir-196a-5p may contribute to tumorgenesis, suggesting roles as an oncogenic miRNA biomarker in gastric cancer.


Assuntos
Biomarcadores Tumorais/genética , Metabolismo Energético/genética , MicroRNAs/genética , Neoplasias Gástricas/genética , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , MicroRNAs/biossíntese , Pessoa de Meia-Idade , Transcrição Gênica/genética , Regulação para Cima
13.
Int J Mol Med ; 33(6): 1451-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24676394

RESUMO

Gastric cancer, one of the most common malignancies worldwide, typically has a poor prognosis and poor survival rate. Previous studies have investigated the chemopreventive effect of celecoxib. In the present study, the SGC-7901 human gastric cancer cell line was utilized to examine the chemopreventive mechanisms of celecoxib. The inhibition of cell proliferation was determined using MTT assay, cell apoptosis was monitored by terminal deoxynucleotidyl transferase-mediated dUTP nick end­labeling (TUNEL) and flow cytometry, and cell ultrastructural changes were assessed via transmission electron microscopy. The mRNA expression of Akt, caspase-8 and -9 was examined using quantitative reverse-transcription-polymerase chain reaction (qRT-PCR) and p-Akt, procaspase-8 and -9 were analyzed via western blotting. The results showed that celecoxib inhibited the proliferation of SGC-7901 cells in a time- and dose-dependent manner. Additionally, celecoxib induced apoptosis as substantiated by typical apoptotic bodies, autophagosomes and an increased apoptotic rate. It was found that following celecoxib treatment, Akt mRNA expression was not significantly altered, and that p-Akt protein levels decreased in a time- and dose­dependent manner. Additionally, caspase-8 and -9 mRNA expression was significantly increased, while procaspase-8 and -9 protein expression decreased relative to the time- and dose-dependent effects. These results demonstrated that celecoxib induced apoptosis and autophagy of gastric cancer cells in vitro through the PI3K/Akt signaling pathway. Moreover, our findings suggested that celecoxib induces apoptosis in gastric cancer cells through the mitochondrial and death receptor pathways, providing additional understanding regarding the chemopreventive behaviors of celecoxib and its uses in cancer therapy.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pirazóis/farmacologia , Neoplasias Gástricas/metabolismo , Sulfonamidas/farmacologia , Western Blotting , Caspase 8/metabolismo , Caspase 9/metabolismo , Celecoxib , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citometria de Fluxo , Humanos , Marcação In Situ das Extremidades Cortadas , Microscopia Eletrônica de Transmissão , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
14.
World J Gastroenterol ; 19(37): 6265-71, 2013 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-24115825

RESUMO

AIM: To investigate the mechanisms of how cyclooxygenase-2 (COX-2) regulates E-cadherin in gastric cancer cells. METHODS: COX-2 expression in human gastric cancer cell lines SGC-7901, BGC-823, MGC-803 and AGS were measured at the mRNA and protein level. COX-2 rich cell line SGC-7901 was chosen for subsequent experiments. siRNA mediated gene knockdown was used to investigate the impact of COX-2 on nuclear factor-κB (NF-κB), Snail, and E-cadherin in gastric cancer cells. Gene expression was determined by Western blot and real-time polymerase chain reaction. To analyze whether NF-κB inhibition could interrupt the modulatory effect of COX-2 or prostaglandin E2 (PGE2) on E-cadherin, gastric cancer cells were treated with celecoxib or PGE2, in the presence of NF-κB specific siRNA. RESULTS: Highest expression level of COX-2 was found in SGC-7901 cells, both at mRNA and protein levels. siRNA mediated down-regulation of COX-2 led to a reduced expression of NF-κB and Snail, but an increased expression of E-cadherin in SGC-7901 cells. siRNA mediated down-regulation of NF-κB also led to a reduced expression of E-cadherin and Snail in SGC-7901 cells. However, COX-2 expression did not alter after cells were treated with NF-κB specific siRNA in SGC-7901 cells. Treatment of SGC-7901 cells with celecoxib led to a reduced expression of Snail but an increased expression of E-cadherin. In contrast, treatment of SGC-7901 cells with PGE2 led to an increased Snail and a decreased E-cadherin. However, siRNA-mediated knockdown of NF-κB partially abolished the effect of celecoxib and PGE2 on the regulation of E-cadherin and Snail in SGC-7901 cells. CONCLUSION: COX-2 likely functions upstream of NF-κB and regulates the expression of E-cadherin via NF-κB/Snail signaling pathway in gastric cancer cells.


Assuntos
Caderinas/metabolismo , Ciclo-Oxigenase 2/metabolismo , Neoplasias Gástricas/enzimologia , Fatores de Transcrição/metabolismo , Antígenos CD , Caderinas/genética , Linhagem Celular Tumoral , Ciclo-Oxigenase 2/genética , Dinoprostona/metabolismo , Humanos , NF-kappa B/metabolismo , Interferência de RNA , Transdução de Sinais , Fatores de Transcrição da Família Snail , Neoplasias Gástricas/genética , Fatores de Transcrição/genética , Transfecção
15.
Inorg Chem ; 49(18): 8270-5, 2010 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-20718431

RESUMO

In an attempt to synthesize novel zirconium phosphate materials, a series of syntheses have been performed in a deep eutectic solvent (DES), composed of tetrapropylammonium bromide (TPABr) and oxalic acid. As a result, this DES does not act as a template provider in reaction probably owing to the steric effects of the longer chains of the TPA cation, and only the α-Zr(HPO(4))(2)·H(2)O (α-ZrP) phase has been achieved. However, after organic amine was added to the initial reaction mixture in a normal way, the additives did act as a template to induce the zirconium phosphate framework. For example, with 1,4-dimethylpiperazine as an additive, a novel layered compound, [C(6)H(16)N(2)](0.5)Zr(H(0.5)PO(4))(2)·H(2)O (denoted as ZrPO(4)-DES8) was obtained. Its structure was determined from single-crystal X-ray diffraction (XRD) data and consists of zirconium phosphate layers with the protonated 1,4-dimethylpiperazine and water molecules in between. Interestingly, the two layered materials as additives in a liquid lubricant exhibit excellent friction behavior with higher load-carrying and antiwear capacities in comparison to typical lubricant additives such as MoS(2) and graphite, increase the P(B) value of the base oil by 27.2% and 8.5%, and decrease the wear scar diameter of the base oil by 43% and 36%, respectively. Scanning electron microscopy, XRD, and energy-dispersive X-ray spectrometry are used to investigate the lubricant behavior of those materials.

16.
Zhonghua Zhong Liu Za Zhi ; 31(9): 674-8, 2009 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-20021863

RESUMO

OBJECTIVE: To investigate the expression of Ets-1 in gastric carcinoma, para-cancerous tissue and metastatic lymph nodes, and to determine the relationship between Ets-1 expression and clinicopathological features, angiogenesis and survival of patients with gastric carcinoma. METHODS: Gastric carcinoma tissue microarray was used to determine Ets-1 protein expression by SP immunohistochemical staining in 189 advanced gastric cancer, 54 papacancerous tissues, 41 metastatic lymph nodes and 32 control tissues. RESULTS: The positive rates for Ets-1 expression of the carcinoma, paracancerous and control tissues were 71.4%, 29.6% and 18.8%, respectively, with a significant difference among the three groups (P < 0.01). In the cancer tissues, the positive rate of Ets-1 protein expression was significantly associated with depth of invasion and lymph node metastasis (P < 0.01), but not associated with degree of differentiation, Lauren's histological type, sex, age, and size of tumor (P > 0.05). The positive rates for Ets-1 expression of the 41 gastric cancer and 41 metastatic lymph nodes were significantly different (P < 0.05). In metastatic lymph nodes, the positive rate for Ets-1 expression was higher. The MVD in Ets-1 positive tumors was higher than that in the Ets-1 negative tumors, with a significant difference (P < 0.05). Kaplan-Meier survival analysis showed that the survival time of Ets-1-negative patients was longer than that of Ets-1-positive patients (P < 0.05). Cox regression analysis showed that Ets-1 expression was not an independent prognostic factor of gastric carcinoma. CONCLUSION: A higher expression of Ets-1 is involved in carcinogenesis, development, invasion, and metastasis of gastric cancer. Ets-1 plays an important role in angiogenesis in gastric cancer. Ets-1 is a useful marker for predicting the outcome for patients with gastric carcinoma, though it is not an independent prognostic indicator.


Assuntos
Microvasos/patologia , Proteína Proto-Oncogênica c-ets-1/metabolismo , Neoplasias Gástricas/metabolismo , Adulto , Idoso , Feminino , Humanos , Metástase Linfática , Masculino , Microvasos/metabolismo , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Inclusão em Parafina , Modelos de Riscos Proporcionais , Neoplasias Gástricas/patologia , Taxa de Sobrevida
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