Search

Primary brain tumors are a rare occurrence in comparison to other malignancies, the most predominant form being glioma. Commonly, exposure to ionizing radiations and inheritance of associated conditions such a neurofibromatosis and tuberous sclerosis are the most common causes of development of glioma. However, understanding of the molecular mechanisms that drive glioma development is limited. We explore the role of aberration of microRNA namely miR-494-3p through long noncoding RNA WT1-AS in the development of gliomas. In this study, we found that, levels of WT1-AS were significantly reduced in glioma tissues and cell lines. The miR-494-3p levels were negatively correlated with WT1-AS levels. The cellular proliferation and invasiveness decreased in WT1-AS transfected cell lines. Further the half maximal inhibitory concentration (IC50) of chemotherapeutic agent temozolomide was significantly reduced in the presence of WT1-AS. The cotransfection of WT1-AS and miR-494-3p reduced activation of phospho-AKT (p-AKT). Expression of miR-494-3p is modulated by binding to long noncoding RNA WT1-AS. Deregulation of WT1-AS leads to aberrant expression of miR-494-3p leading to hyperactivation of AKT. This malformation may result in altering protective immune responses in malignancies. Targeting of WT1-AS, miR-494-3p, and AKT may be novel therapeutic options in treatment of glioma.

The primary objective of this study is to develop day and night road traffic noise maps for Guangzhou using Geographical Information Systems (GIS) and Global Positioning Systems (GPS). First, as speed-density relation is used to estimate the traffic volume from GPS data collected from floating cars. Meanwhile, the attributes of the roads and buildings are automatically exported from GIS. Second, a single vehicle noise emission model is combined with a noise propagation model to formulate a regional traffic noise calculation model that accounts for the traffic noise attenuation in an urban area. The algorithm is optimized by intelligently dividing the computational grids, filtering the traffic noise sources automatically and performing a quick index of the estimation objects. Finally, the day and night road traffic noise levels in Guangzhou are estimated to create two traffic noise maps. The accuracy of the developed algorithm is validated by conducting a traffic noise monitoring experiment in several districts of Guangzhou with different road types. The results show that the average error between the estimated and measured values is below 2.0 dB.

Background/Aims: Hyperuricemia is part of the metabolic-syndrome cluster of abdominal obesity, impaired glucose tolerance, insulin resistance, dyslipidemia, and hypertension. Monocytes/macrophages are critical in the development of metabolic syndrome, including gout, obesity and atherosclerosis. However, how high uric acid (HUA) exposure affects monocyte/macrophage function remains unclear. In this study, we investigated the molecular mechanism of HUA exposure in monocytes/macrophages and its impact on oxidized low-density lipoprotein (oxLDL)-induced foam-cell formation in a human monocytic cell line, THP-1. Methods: We primed THP-1 cells with phorbol-12-myristate-13-acetate (PMA) for differentiation, then exposed cells to HUA and detected the production of reactive oxygen species (ROS) and analyzed the level of phospho-AMPKα. THP-1 cells were pre-incubated with Compound C, an AMPK inhibitor, or N-acetyl-L-cysteine (NAC), a ROS scavenger, or HUA before PMA, to assess CD68 expression and phospho-AMPKα level. PMA-primed THP-1 cells were pre-treated with oxLDL before Compound C and HUA treatment. Western blot analysis was used to examine the levels of phospho-AMPKα, CD68, ABCG1, ABCA1, cyclooxygenase-2 (COX-2) and NF-κB (p65). Flow cytometry was used to assess ROS production and CD68 expression in live cells. Oil-red O staining was used to observe oxLDL uptake in cells. Results: HUA treatment increased ROS production in PMA-primed THP-1 cells; NAC blocked HUA-induced oxidative stress. HUA treatment time-dependently increased phospho-AMPKα level in PMA-primed THP-1 cells. The HUA-induced oxidative stress increased phospho-AMPKα levels, which was blocked by NAC. HUA treatment impaired CD68 expression during cell differentiation by activating the AMPK pathway, which was reversed by Compound C treatment. Finally, HUA treatment inhibited oxLDL uptake in the formation of foam cells in THP-1 cells, which was blocked by Compound C treatment. HUA treatment significantly increased the expression of ABCG1 and reversed the oxLDL-reduced ABCG1 expression but did not affect the expression of ABCA1, NF-κB (p65) or COX-2. Conclusions: HUA exposure activated the ROS-AMPK pathway, impaired CD68 expression, and inhibited oxLDL-induced foam-cell formation in a human monocytic cell line, THP-1.

Metformin is an oral biguanide commonly used for treating type II diabetes and has recently been reported to possess antiproliferative properties that can be exploited for the prevention and treatment of a variety of cancers. The mechanisms underlying this effect have not been fully elucidated. Our study shows a marked loss of AMP-activated protein kinase (AMPK) phosphorylation and nuclear human Forkhead box O1 (FOXO1) protein in estrogen-dependent endometrial cancer (EC) tumors compared to normal control endometrium. Metformin treatment suppressed EC cell growth in a time-dependent manner in vitro; this effect was cancelled by cotreatment with an AMPK inhibitor, compound C. Metformin decreased FOXO1 phosphorylation and increased FOXO1 nuclear localization in Ishikawa and HEC-1B cells, with non-significant increase in FOXO1 mRNA expression. Moreover, compound C blocked the metformin-induced changes of FOXO1 and its phosphorylation protein, suggesting that metformin upregulated FOXO1 activity by AMPK activation. Similar results were obtained after treatment with insulin. In addition, transfection with siRNA for FOXO1 cancelled metformin-inhibited cell growth, indicating that FOXO1 mediated metformin to inhibit EC cell proliferation. A xenograft mouse model further revealed that metformin suppressed HEC-1B tumor growth, accompanied by downregulated ki-67 and upregulated AMPK phosphorylation and nuclear FOXO1 protein. Taken together, these data provide a novel mechanism of antineoplastic effect for metformin through the regulation of FOXO1, and suggest that the AMPK-FOXO1 pathway may be a therapeutic target to the development of new antineoplastic drugs.

In order to master the distribution of traffic noise pollution and put forward reasonable noise reduction measures, it is essential to map the traffic noise. This paper adopted video identification and artificial statistical methods to obtain the information of traffic flow and vehicle speed by carrying out a 24 hour traffic flow investigation for the whole road network of Chancheng district. Then combined with the geographical information system and based on the FHWA model, an urban traffic noise simulation system was developed independently to calculate the traffic noise of the district. According to the calculated data, a day-night traffic noise map of the road network was painted. Furthermore, noise reduction measures such as “odd-even” traffic restrictions and installing sound barriers were assessed. Traffic noise mapping can help public authorities derive traffic management policies to reduce urban traffic noise.