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Purpose: Nasopharyngeal carcinoma (NPC) is one of the most malignant head and neck carcinomas with unique epidemiological features. In this study, we aimed to identify the novel NPC-related genes and biological pathways, shedding light on the potential molecular mechanisms of NPC. Methods: Based on Gene Expression Omnibus (GEO) database, an integrated analysis of microarrays studies was performed to identify differentially expressed genes (DEGs) and differentially methylated genes (DMGs) in NPC compared to normal control. The genes which were both differentially expressed and differentially methylated were identified. Functional annotation and protein–protein interaction (PPI) network construction were used to uncover biological functions of DEGs. Results: Two DNA methylation and five gene expression datasets were incorporated. A total of 1074 genes were up-regulated and 939 genes were down-regulated in NPC were identified. A total of 719 differential methylation CpG sites (DMCs) including 1 hypermethylated sites and 718 hypomethylated sites were identified. Among which, 11 genes were both DEGs and DMGs in NPC. Pathways in cancer, p53 signaling pathway and Epstein–Barr virus infection were three pathways significantly enriched pathways in DEmRNAs of NPC. The PPI network of top 50 DEGs were consisted of 191 nodes and 191 edges. Conclusions: Our study was helpful to elucidate the underlying mechanism of NPC and provide clues for therapeutic methods. [ABSTRACT FROM AUTHOR]

Common biological effects by all three conventional anti-bipolar drugs, the lithium ion (Li+), carbamazepine, and valproic acid, are important because identical effects may provide information about the pathophysiology of affective disorders. It has been reported that chronic treatment with either drug in vivo down-regulates the turnover of arachidonic acid in brain. This reaction is catalyzed by Ca2+-dependent phospholipase A2 (cPLA2), the expression of which was down-regulated by Li+ or carbamazepine but not by valproic acid; expression of two other PLA subtypes, iPLA2 and sPLA2 was unaffected. cPLA2 is amply expressed in astrocytes, and in the present study, effects of 1–4 weeks of treatment with clinically relevant concentrations of each of the three anti-bipolar drugs on cPLA2, iPLA2, and sPLA2 mRNA and protein expression were determined in primary cultures of mouse astrocytes by reverse transcription polymerase chain reaction (RT-PCR) and immunoblotting. Two or more weeks treatment with Li+ concentrations below 2 mM, carbamazepine or valproic acid up-regulated mRNA and protein expression of cPLA2, but had no effect on iPLA2 and sPLA2, showing enzyme specificity. The effect occurred more rapidly at higher than lower concentrations but also tended to end after 4 weeks at the higher concentrations. Two millimolar Li+ caused an initial increase of cPLA2 followed by a decrease after 3 and 4 weeks. Topiramate had no effect, indicating specificity for anti-bipolar drugs. Both up- and down-regulation of cPLA2 gene expression are involved in the mechanisms of action of anti-bipolar drugs; astrocytes are a target for these drugs. [ABSTRACT FROM AUTHOR]