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Background and purpose: Glioma is a frequent primary brain tumor. MicroRNAs (miRNA) have been shown to potentially play a crucial part in tumor development. Based on miRNAs and clinical factors, a model was constructed to predict the glioma prognosis. Methods: The miRNA expression profiles of glioma come from The Cancer Genome Atlas (TCGA, training group) and Chinese Glioma Genome Atlas (CGGA, validation group). Regression analyses of Cox and Lasso were applied to identity miRNAs associated with glioma prognosis in the TCGA database. The miRNAs were combined with clinical factors to construct individualized prognostic prediction models, whose performance was validated in the CGGA database. The role of miRNA in glioma development was investigated by in vitro experiments. Results: We identified five key miRNAs associated with glioma prognosis and constructed a prediction model. The area under ROC curve for predicting 3-year survival of glioma patients in the TCGA and CGGA groups was 0.844 and 0.770, respectively. The nomogram constructed using the miRNA risk scores and clinical factors showed high accuracy of prediction in the TCGA group (C-index of 0.820) and the CGGA group (C-index of 0.722). The miR-196b-5p altered the migration, proliferation, invasion, and apoptosis of glioma cells by regulating target genes, according to in vitro experiments. Conclusions: A miRNA-based individualized prognostic prediction model was constructed for glioma and miR-196b-5p was identified as a potential biomarker of glioma development. [ABSTRACT FROM AUTHOR]

Purpose: The family of Toll-like receptors (TLRs) has recently been reported to play a role in ischemic injury, but the time course and cell types of the post-stroke TLR9 upregulation remain unclear. In this study, we investigated the dynamic changes of TLR9 expression and the expression of TLR9 in neurons and glial cells after cerebral ischemia reperfusion in mice.Methods: Focal cerebral ischemia was induced by middle cerebral artery occlusion for 90 min in male C57BL/6 mice. The TLR9 expression levels in the tissue surrounding the infarct were detected by Western Blot at 6 h, 3 d, 7 d, 14 d, 21 d, and 28 d after reperfusion. The expression of TLR9 in neurons and glial cells was observed by immunofluorescence staining.Results: The expression of TLR9 protein first increased and then decreased, with the peak observed at 14 d–21 d. Only small punctate intracellular TLR9 was occasionally observed in the neurons at each time point, and the TLR9-positive rate showed no difference at different time points. By contrast, the activated microglia gathered at the margin of the infarct, and the intracellular TLR9 changed from scattered small punctate to coarse and lumpy. The TLR9-positive rate of microglia was first increased and then decreased with time, with the peak observed at 3 d. No positive TLR9 staining was found in the astrocytes and oligodendrocytes.Conclusions: TLR9 expression showed dynamic changes for a long period of time and microglias were the main brain cells to express TLR9 after cerebral ischemia and reperfusion. [ABSTRACT FROM PUBLISHER]