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1.
Pharmacol Res ; 187: 106606, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36516884

RESUMO

Epidermal growth factor receptor variant III (EGFRvIII) is a mutant isoform of EGFR with a deletion of exons 2-7 making it insensitive to EGF stimulation and downstream signal constitutive activation. However, the mechanism underlying the stability of EGFRvIII remains unclear. Based on CRISPR-Cas9 library screening, we found that mucin1 (MUC1) is essential for EGFRvIII glioma cell survival and temozolomide (TMZ) resistance. We revealed that MUC1-C was upregulated in EGFRvIII-positive cells, where it enhanced the stability of EGFRvIII. Knockdown of MUC1-C increased the colocalization of EGFRvIII and lysosomes. Upregulation of MUC1 occurred in an NF-κB dependent manner, and inhibition of the NF-κB pathway could interrupt the EGFRvIII-MUC1 feedback loop by inhibiting MUC1-C. In a previous report, we identified AC1Q3QWB (AQB), a small molecule that could inhibit the phosphorylation of NF-κB. By screening the structural analogs of AQB, we obtained EPIC-1027, which could inhibit the NF-κB pathway more effectively. EPIC-1027 disrupted the EGFRvIII-MUC1-C positive feedback loop in vitro and in vivo, inhibited glioma progression, and promoted sensitization to TMZ. In conclusion, we revealed the pivotal role of MUC1-C in stabilizing EGFRvIII in glioblastoma (GBM) and identified a small molecule, EPIC-1027, with great potential in GBM treatment.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioma , Humanos , Temozolomida/farmacologia , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/metabolismo , NF-kappa B/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Mucina-1/genética
2.
Carcinogenesis ; 40(8): 956-964, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-30809632

RESUMO

Long non-coding RNAs (lncRNAs) have been reported to play important roles in glioma; however, most of them promote glioma progression. We constructed a competing endogenous (ceRNA) network based on the Chinese Glioma Genome Atlas dataset, and lncRNA hect domain and RLD 2 pseudogene 2 (HERC2P2) is the core of this network. Highly connected genes in the ceRNA network classified the glioma patients into three clusters with significantly different survival rates. The expression of HERC2P2 is positively correlated with survival and negatively correlated with clinical grade. Cell colony formation, Transwell and cell scratch tests were performed to evaluate the role of HERC2P2 in glioblastoma growth. Furthermore, we overexpressed HERC2P2 in U87 cells and established a mouse intracranial glioma model to examine the function of HERC2P2 in vivo. In conclusion, we identified a lncRNA with tumor suppressor functions in glioma that could be a potential biomarker for glioma patients.


Assuntos
Biomarcadores Tumorais/genética , Glioma/genética , Prognóstico , RNA Longo não Codificante/genética , Animais , Linhagem Celular Tumoral , Biologia Computacional , Bases de Dados Factuais , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Redes Reguladoras de Genes/genética , Genes Supressores de Tumor , Glioma/patologia , Xenoenxertos , Humanos , Estimativa de Kaplan-Meier , Masculino , Camundongos , MicroRNAs/genética , Taxa de Sobrevida
3.
J Nanosci Nanotechnol ; 19(4): 2108-2115, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30486953

RESUMO

A stability analyser and a rheometer were used to study the effects of Tween 85 (polyoxyethylene sorbitan trioleate) on the dispersion properties of nano-aluminium/JP-10 (exo-tetrahydrodicyclopentadiene) suspensions. Results show that the addition of Tween 85 can effectively improve the stability of two-phase suspensions by hindering particle aggregation and reduce the viscosity of a system. The surface characteristics of the zeta potential and the contact angle were measured. The dispersion of the suspensions was improved by Tween 85 mainly by enhancing the steric hindrance of particles. The adsorbed particles obtained in JP-10 with different Tween 85 concentrations were analysed via scanning electron microscopy and Fourier transform infrared spectroscopy to explore the adsorption behaviour of Tween 85 molecules on the surface of aluminium particles and to confirm that Tween 85 formed an adsorption layer on the particle surface. Thermogravimetric analysis indicated that the adsorption amount of Tween 85 increased with its concentration in JP-10. The roughness analysis of the surface of adsorbed particles was measured via atomic force microscopy to characterise the thickness of the adsorption layer. The results showed that Tween 85 molecules formed an irregular adsorption layer on the particle surface, and an increase in the concentration of Tween 85 in JP-10 increased the thickness of the adsorption layer.

4.
Cancer Lett ; 403: 119-127, 2017 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-28634045

RESUMO

EGFR amplification and mutations are the most common oncogenic events in GBM. EGFR overexpression correlates with GBM invasion, but the underlying mechanisms are poorly understood. In a previous study, we showed that AJAP1 is involved in regulating F-actin to inhibit the invasive ability of GBM. In addition, in a GBM cell line, the AJAP1 promoter was highly bound by H3K27me3 and, through bioinformatics analysis, we found that AJAP1 expression was negatively correlated with EGFR. In this study, we found that the pathway downstream of EGFR had a higher activation level in GBM cell lines, which led to excessive tumor suppressor silencing. Therefore, we deduced that in glioma cells, the pathway downstream of EGFR remodels the cytoskeleton via AJAP1 epigenetic silencing to enhance invasion. Furthermore, MK2206 reversed AJAP1 downregulation by inhibiting the EGFR pathway. In vivo, MK2206 also inhibited the proliferation and local invasion of 87-EGFRvIII. These data suggest that activation of the EGFR signal transduction pathway genetically silences anti-oncogenes to enhance GBM malignancy. MK2206 might be a promising therapeutic for EGFR/EGFRvIII-positive GBMs.


Assuntos
Citoesqueleto de Actina/metabolismo , Neoplasias Encefálicas/metabolismo , Moléculas de Adesão Celular/metabolismo , Movimento Celular , Metilação de DNA , Epigênese Genética , Receptores ErbB/metabolismo , Animais , Antineoplásicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Moléculas de Adesão Celular/genética , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Biologia Computacional , Bases de Dados Genéticas , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Receptores ErbB/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Compostos Heterocíclicos com 3 Anéis/farmacologia , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Fosfatidilinositol 3-Quinase/metabolismo , Regiões Promotoras Genéticas , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , Transdução de Sinais , Transfecção , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Cancer Lett ; 388: 269-280, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-27998759

RESUMO

Worldwide, glioblastoma (GBM) is the most lethal and frequent intracranial tumor. Despite decades of study, the overall survival of GBM patients remains unchanged. epidermal growth factor receptor (EGFR) amplification and gene mutation are thought to be negatively correlated with prognosis. In this study, we used proteomics to determine that UBXN1 is a negative downstream regulator of the EGFR mutation vIII (EGFRvIII). Via bioinformatics analysis, we found that UBXN1 is a factor that can improve glioma patients' overall survival time. We also determined that the down-regulation of UBXN1 is mediated by the upregulation of H3K27me3 in the presence of EGFRvIII. Because NF-κB can be negatively regulated by UBXN1, we believe that EGFRwt/vIII activates NF-κB by suppressing UBXN1 expression. Importantly, we used the latest genomic editing tool, CRISPR/Cas9, to knockout EGFRwt/vIII on exon 17 and further proved that UBXN1 is negatively regulated by EGFRwt/vIII. Furthermore, knockout of EGFR/EGFRvIII could benefit GBM in vitro and in vivo, indicating that CRISPR/Cas9 is a promising therapeutic strategy for both EGFR amplification and EGFR mutation-bearing patients.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Glioma/genética , Glioma/metabolismo , NF-kappa B/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Epigenômica , Receptores ErbB/metabolismo , Éxons , Feminino , Humanos , Camundongos , Camundongos Nus , Transdução de Sinais , Transfecção
6.
J Zhejiang Univ Sci B ; 6(3): 187-94, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15682503

RESUMO

Pulverized coal reburning, ammonia injection and advanced reburning in a pilot scale drop tube furnace were investigated. Premix of petroleum gas, air and NH3 were burned in a porous gas burner to generate the needed flue gas. Four kinds of pulverized coal were fed as reburning fuel at constant rate of 1g/min. The coal reburning process parameters including 15% approximately 25% reburn heat input, temperature range from 1100 degrees C to 1400 degrees C and also the carbon in fly ash, coal fineness, reburn zone stoichiometric ratio, etc. were investigated. On the condition of 25% reburn heat input, maximum of 47% NO reduction with Yanzhou coal was obtained by pure coal reburning. Optimal temperature for reburning is about 1300 degrees C and fuel-rich stoichiometric ratio is essential; coal fineness can slightly enhance the reburning ability. The temperature window for ammonia injection is about 700 degrees C approximately 1100 degrees C. CO can improve the NH3 ability at lower temperature. During advanced reburning, 72.9% NO reduction was measured. To achieve more than 70% NO reduction, Selective Non-catalytic NO(x) Reduction (SNCR) should need NH3/NO stoichiometric ratio larger than 5, while advanced reburning only uses common dose of ammonia as in conventional SNCR technology. Mechanism study shows the oxidization of CO can improve the decomposition of H2O, which will rich the radical pools igniting the whole reactions at lower temperatures.


Assuntos
Poluentes Atmosféricos/química , Monóxido de Carbono/química , Carvão Mineral , Temperatura Alta , Modelos Químicos , Óxidos de Nitrogênio/química , Poluentes Atmosféricos/isolamento & purificação , Simulação por Computador , Óxidos de Nitrogênio/isolamento & purificação , Oxirredução , Temperatura
7.
Huan Jing Ke Xue ; 29(8): 2361-5, 2008 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-18839601

RESUMO

Calcination of oganic calcium was carried out in fixed bed, pore structure of tested sample was analyzed with auto-adsorption analyzer, and desulfurization experiment was studied by intelligent sulfur determination analyzer. Specific surface area of calcium magnesium acetate (CMA) was 46.6 m2/g after calcination at 900 degrees C, almost four times of that of limestone. Specific surface area of calcium acetate (CA) were mainly made up of pore of diameter less than 5 nm, and those of CMA was chiefly contributed by middle pore of diameter about 5 nm. Agglomeration of CA occurred in pore of diameter less than 5 nm, while CMA was sintered in whole range of pore size distribution. Agglomeration of organic calcium were slighter. Desulfurization efficiency of organic calcium ranged from 62.28% to 75.55% at 1000 degrees C as calcium/sulfur ratio being one, which was one time more than that of limestone. Perfect pore structure of organic calcium contributes to higher desulfurization efficiency.


Assuntos
Acetatos/química , Poluentes Atmosféricos/isolamento & purificação , Sulfeto de Hidrogênio/isolamento & purificação , Dióxido de Enxofre/isolamento & purificação , Poluentes Atmosféricos/química , Compostos de Cálcio/química , Sulfeto de Hidrogênio/química , Compostos Orgânicos/química , Porosidade , Dióxido de Enxofre/química
8.
Huan Jing Ke Xue ; 28(5): 1153-7, 2007 May.
Artigo em Chinês | MEDLINE | ID: mdl-17633195

RESUMO

Biohydrogen production from straw by anaerobic fermentation of digested sludge was studied. The influence of the main parameters such as particle size, the ratio of substrate to cellulase, pretreatment method and pH on the straw fermentation was investigated. With NaOH pretreatment, the rice straw with average particle size of 170 tm was fermented after hydrolyzed by cellulase with the ratio of substrate to cellulase as 1:1. And its maximal velocity and the total volume of hydrogen are respectively 0.58 mL/(h x g) and 90.5 m/g.


Assuntos
Bactérias Anaeróbias/metabolismo , Fermentação , Hidrogênio/metabolismo , Caules de Planta/metabolismo , Reatores Biológicos , Hidrogênio/análise , Concentração de Íons de Hidrogênio , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Caules de Planta/crescimento & desenvolvimento , Eliminação de Resíduos/métodos
9.
Huan Jing Ke Xue ; 28(8): 1861-5, 2007 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-17926424

RESUMO

Aim to control the emission of SO2 during coal combustion, desulfurization characteristic of organic calcium was studied by intelligent sulfur determination analyzer. Sulfur releasing curve changed from two "peak value" to one for addition of organic calcium, with velocity of SO2 release decreasing. Efficiency of sulfur reduction was double when organic calcium was used under 1 000 degrees C compared to limestone, and reduction efficiency of calcium magnesium acetate was 73.84%. Sulfur content, furnace temperature, calcium/sulfur ratio and paticle's diameter were important factors as for desulfurizing rate. Sulfur removal efficiency was improved with coal's sulfur content increasing or particle's diameter decreasing. Decreasing degree of reduction efficiency lowered with sulfur content increasing as temperature improved. Efficiency remained high level as 59.08% by calcium magnesium acetate at 1 200 degrees C. Perfect efficiency could be reached as calcium/sulfur ratio being one and augmentation degree was inapparent with more calcium addition. Therefore organic calciums are excellent absorbent for desulfurization and calcium magnesium acetate has best sulfur removal efficiency.


Assuntos
Poluentes Atmosféricos/química , Compostos de Cálcio/química , Resíduos Industriais/prevenção & controle , Compostos Orgânicos/química , Dióxido de Enxofre/química , Adsorção , Carbonato de Cálcio/química , Carvão Mineral , Temperatura Alta , Enxofre/química , Volatilização
10.
Huan Jing Ke Xue ; 27(8): 1512-5, 2006 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-17111603

RESUMO

Effectiveness of calcium magnesium acetate (CMA) and calcium acetate(CA) as feasible HF capture were studied by means of fixed bed tube furnaces. The effects of temperature, particle diameter and Ca/S molar ratio on the fluorine removal efficiency were studied. By contract with CaCO3 at the same condition, we find that the HF capture effectiveness of those sorbents is superior to CaCO3, especially at high temperature. At 1 000 - 1 100 degrees C, the efficiency of fluorine removal during coal combustion of CMA is 1.68 - 1.74 times as that of CaCO3; the efficiency of fluorine removal during coal combustion of CA is 1.28 - 1.37 times as that of CaCO3.


Assuntos
Poluentes Atmosféricos/química , Compostos de Cálcio/química , Carvão Mineral/análise , Flúor/química , Absorção , Acetatos/química , Carbonato de Cálcio/química , Flúor/análise , Temperatura Alta , Enxofre/análise , Gerenciamento de Resíduos/métodos
11.
Huan Jing Ke Xue ; 26(1): 12-5, 2005 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-15859400

RESUMO

The paper is about the emission of fluorine from an experimental boiler of 0.25 MW when burning black liquor coal-water slurry (CWS). The result is compared with CWS. And the analysis of effect factors is also carried out. Experimental research show that, the content of fluorine in CWS, which was less than 30 mg/kg, was relatively low. The emission ratio and concentration of fluorine were 70% - 90% and 2.0 - 2.6 mg/m3 respectively when burning common CWS; while the data of those when combusting black liquor CWS were 45% - 80% and 1.7 - 3.0 mg/m3 respectively. The hearth temperature and the element of CWS were two factors of emission fluorine when burning CWS.


Assuntos
Poluentes Atmosféricos/análise , Carvão Mineral/análise , Flúor/análise , Carbono , Cinza de Carvão , Fontes de Energia Elétrica , Calefação , Material Particulado , Água
12.
Huan Jing Ke Xue ; 25(2): 174-6, 2004 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-15202259

RESUMO

In the paper, the reaction of CaO-HF and fluorine removal mechanics at high temperature by blending calcium-based sorbents with coal during coal combustion were discussed, and test results about fluorine retention during coal combustion in fluidized bed and chain-grate furnace were reported. The results identified that lime and calcium-based sorbets developed can restratin the emission of fluorine during coal combustion. The efficiency of fluorine removal can reach 66.7%-70.0% at Ca/F 60-70 by blending lime with coal in fluidized bed combustion, and the efficiency of fluorine removal are between 57.32% and 75.19% by blending calcium-based sorbets with coal in chain-grate furnace combustion. Blending CaO or lime with coal during coal combustion can remove SO2 and HF simultaneously.


Assuntos
Compostos de Cálcio/farmacologia , Carvão Mineral , Flúor/isolamento & purificação , Óxidos/farmacologia , Absorção , Temperatura Alta
13.
Artigo em Chinês | WPRIM | ID: wpr-328844

RESUMO

<p><b>OBJECTIVE</b>The paper is a study on the clinical symptoms and pathogeny of ectrodactyly and absence of radius side part palm and split foot malformation of some patients in one family.</p><p><b>METHODS</b>Based on the patient family investigation,a normal control group and a patient group were established. Then, polymerase chain reaction technique was used for DNA sequencing and analysis of the two groups for their exons 5-8 gene group DNA of P63 gene.</p><p><b>RESULTS</b>The medical examination found that the patients' upper bilateral limbs are short of thumbs, forefingers and middle fingers, and have radius side part palm and double lower limbs foot clefts malformation. The pathogeny research revealed that the PCR expansion pieces of the exons 5-8 of P63 are 284 bp, 259 bp, 245 bp and 259 bp respectively, and the size of the expansion piece of the patients was the same as that of the normal people group. However, a respective comparison between the DNA serial of the expansion piece of the patient and that of the normal people group and that of the P63 gene in the human gene bank showed that mutation occurs at the number 665 base pair of exon 5 of P63, namely a mutation from G to A.</p><p><b>CONCLUSION</b>The ectrodactyly, absence of radius side part palm and split foot malformation are caused by the mutation of base pair at number 665 of the exon 5 of P63.</p>


Assuntos
Feminino , Humanos , Masculino , Éxons , Genética , Deformidades Congênitas do Pé , Genética , Patologia , Predisposição Genética para Doença , Deformidades Congênitas da Mão , Genética , Patologia , Proteínas de Membrana , Genética , Mutação , Linhagem , Reação em Cadeia da Polimerase
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