RESUMO
BACKGROUND: Glioma is a type of malignant tumor that occurs in the central nervous system of adults. Long non-coding RNAs (lncRNAs) that potentially participate in the initiation and progression of glioma have been widely reported. As a now-found lncRNA, HLA complex group 11 (HCG11) has not yet been studied in glioma. The present study aimed to determine the role of HCG11 in the tumorigenesis of glioma. METHODS: A quantitative real-time polymerase chain reaction assay was performed to examine the expression pattern of HCG11 in 84 glioma tissues and cell lines. The overall survival rate of glioma patients with a high or low level of HCG11 or metastasis-associated 1 family member 3 (MTA3) was analyzed by Kaplan-Meier analysis. The effect of HCG11 on glioma cell growth was determined by in vitro and in vivo experiments. MicroRNAs (miRNAs) that potentially interact with HCG11 were searched and determined by bioinformatics analysis and a luciferase reporter assay. Similarly, the target of miRNA-4425 was identified. Finally, rescue assays were conducted to determine the bio-function of the competing endogenous RNA pathway. RESULTS: HCG11 was downregulated in 84 pairs of glioma tissues and cell lines. Moreover, a low level of HCG11 indicted the lower overall survival rate of glioma patients. Regarding the mechanism, HCG11 was abundant in the cytoplasm of glioma cells and interacted with miR-4425 to release the expression of MTA3. miR-4425 and MTA3 participated in HCG11-mediated glioma growth. CONCLUSIONS: LncRNA HCG11 suppresses the growth of glioma by cooperating with the miR-4425/MTA3 axis.
Assuntos
Neoplasias Encefálicas/genética , Proliferação de Células/genética , Glioma/genética , MicroRNAs/genética , Proteínas de Neoplasias/genética , RNA Longo não Codificante/genética , Apoptose/genética , Neoplasias Encefálicas/patologia , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular/genética , Progressão da Doença , Regulação para Baixo/genética , Regulação Neoplásica da Expressão Gênica/genética , Glioma/patologia , Humanos , Regulação para Cima/genéticaRESUMO
One of the main challenges faced by microbial fuel cells (MFCs) generating voltage is how to facilitate the oxygen reduction reaction (ORR) process using a specifically designed air cathode, especially by optimizing a three-phase catalytic interface and enhanced O2 diffusion on it. Herein, a three-dimensional porous N-doped graphene aerogel (NGA) is polymerized onto a steel mesh (SM) to construct a simple structure of an air cathode (NGA-x/SM) via hydrothermal synthesis and subsequent freeze-drying treatment; more specifically, NGA was simultaneously used as an efficient ORR catalyst layer and breathable gas diffusion layer to improve the performance of MFCs. In this system, the NGA-5/SM (with a precursor concentration of x = 5.0 mg mL-1) makes itself a perfect candidate to be used as an air cathode. Characterization parameters reveal that sub-micrometer micropores, defective multilayer structures, and the highest proportion of pyridinic-N (48.1%) exist in NGA-5/SM. Furthermore, electrochemical measurements demonstrate that it has an oxygen reduction peak potential of 0.63 V, a Tafel slope of 187 mV dec-1, and closest 4e- transfer pathway (n = 3.2-3.5). These data prove that a three-phase boundary can naturally form in NGA-5/SM, where the ORR occurs. More importantly, this work provides a proof of concept that a Pt-free air cathode could be prepared with high-efficiency NGA by a two-step preparation method to achieve a MFC maximum power density of 1593 mW m-2.