lation of miR-384-5p attenuates rotenone-induced neurotoxicity in dopaminergic SH-SY5Y cells through inhibiting endoplasmic reticulum stress. Am J Physiol Cell Physiol 310: C755-C763, 2016. First published February 10, 2016 doi:10.1152/ajpcell.00226.2015.-Endoplasmic reticulum (ER) stress has been linked to the pathogenesis of Parkinson's disease (PD). However, the role of microRNAs (miRNAs) in this process involved in PD remains poorly understood. Recent studies indicate that miR-384-5p plays an important role for cell survival in response to different insults, but the role of miR-384-5p in PD-associated neurotoxicity remains unknown. In this study, we investigated the role of miR-384-5p in an in vitro model of PD using dopaminergic SH-SY5Y cells treated with rotenone. We found that miR-384-5p was persistently induced by rotenone in neurons. Also, the inhibition of miR-384-5p significantly suppressed rotenone-induced neurotoxicity, while overexpression of miR-384-5p aggravated rotenone-induced neurotoxicity. Through bioinformatics and dual-luciferase reporter assay, miR-384-5p was found to directly target the 3=-untranslated region of glucose-regulated protein 78 (GRP78), the master regulator of ER stress sensors. Quantitative polymerase chain reaction and Western blotting analysis showed that miR-384-5p negatively regulated the expression of GRP78. Inhibition of miR-384-5p remarkably suppressed rotenone-evoked ER stress, which was evident by a reduction in the phosphorylation of activating transcription factor 4 (ATF4) and inositol-requiring enzyme 1 (IRE1␣). The downstream target genes of ER stress including CCAAT/enhancer-binding protein-homologous protein (CHOP) and X box-binding protein-1 (XBP-1) were also decreased by the miR-384-5p inhibitor. In contrast, overexpression of miR-384-5p enhanced ER stress signaling. In addition, knockdown of GRP78 significantly abrogated the inhibitory effect of miR-384-5p inhibitors on cell apoptosis and ER stress signaling. Moreover, we observed a significant increase of miR-384-5p expression in primary neurons induced by rotenone. Taken together, our results suggest that miR-384-5p mediated ER stress by negatively regulating GRP78 and that miR-384-5p inhibition might be a novel and promising approach for the treatment of PD. endoplasmic reticulum stress; Parkinson's disease; miR-384-

Background Recent evidence indicates that Kruppel-like factor 13 (KLF13) has critical roles in regulating cell differentiation, proliferation and may function as a tumor suppressor. However, its role in glioma progression is poorly understood. Methods Public database was used to explore the expression and prognostic value of KLF13 in glioma. Cell proliferation and invasion assays were used to explore the role of KLF13. Bisulfite sequencing and ChIP assay were used to determine the methylation of KLF13 promoter in glioma and the regulation of KLF13 by DNMT1. Results We found that KLF13 inhibited glioma cell proliferation and invasion, which could be reversed by AKT activation. DNMT1-mediated hypermethylation was responsible for downregulation of KLF13. Knocking down of DNMT1 restored KFL13 expression and inhibited cell proliferation and invasion as well. Patients with high expression of KLF13 might have a better prognosis. Conclusion KLF13 suppressed glioma aggressiveness and the regulation of KLF13 could be a potential therapeutic target.

Abstract. The transformation of prostate cancer from an androgen-dependent state to an androgen-independent state is a lethal progression. Alterations in transcriptional programs are the basis of prostate cancer deterioration. The androgen receptor (AR), a member of the nuclear hormone receptor superfamily, mediates prostate cancer progression by functioning primarily through the ligand-activated transcription of target genes. Therefore, a detailed map of AR-regulated genes and AR genomic binding sites is required for hormone-naive and castration-resistant prostate cancer. Through the use of chromatin immunoprecipitation in combination with direct sequencing, 4,143 AR binding sites were defined in the LNCaP androgen-sensitive prostate cancer cell line. Using the same method, 2,380 AR binding regions were identified in the LNCaP-AI long-term androgen-deprived cell line. Approximately 8.5% (354/4,143) of the binding regions were mapped to within 2 kb of the transcription start site (TSS) in the LNCaP cells, while ~12.6% (299/2,380) were mapped to within 2 kb of the TSS in the LNCaP-AI cells. In total, the study mapped 2,796 genes in LNCaP cells and 1,854 genes in LNCaP-AI cells. The cell lines shared 789 mutual genes. In addition, gene ontology (GO) analysis of the genes revealed that there was a notable overlap between the GO terms in the LNCaP cells and LNCaP-AI cells. However, GO terms within the biological process domain that were only observed in the LNCaP-AI cells included the reproduction process, death, immune system process, multi-organism process, pigmentation and viral reproduction. The major genes in the different GO terms were TNFAIP8, RTN4, APP and SYNE1. Through analyzing the AR binding sites in the two cell types, the present study aimed to map potential AR-regulated genes, identify their associated transcription factors and provide a new perspective on the biological processes in the development of prostate cancer. The results provided a valuable data set that furthered the understanding of the genome-wide analysis of AR binding sites in prostate cancer cells, which may be exploited for the development of novel prostate cancer therapeutic strategies.

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