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Background and aim Long non-coding RNAs have been confirmed to play a critical role in various cancers. In the present study, the effect of long non-coding RNA (lncRNA) CCAT1 on glioma cell proliferation and its potential mechanism were investigated. Methods and results Real-time PCR results showed that lncRNA-CCAT1 expression was significantly upregulated in glioma cancer tissues and cell lines compared with controls. After inhibiting CCAT1 expression in glioma cell line U251 with siRNA-CCAT1 (si-CCAT1), the cell viability and cell colony formation were decreased, the cell cycle was arrested in G1 phase, and the cell apoptosis was increased. As reported in bioinformatics software starbase2.0, a total of 22 microRNAs were potentially targeted by CCAT1. It was confirmed that miR-410 was altered most by si-CCAT1. After up-regulating CCAT1 expression in U251 cells, miR-410 level was decreased. Luciferase reporter assay confirmed that CCAT1 targeted miR-410. Correlation analysis showed that CCAT1 expression was negatively related to miR-410 expression in glioma cancer tissues. In addition, down-regulation of miR-410 reversed the inhibitory effect of si-CCAT1 on glioma proliferation. Conclusion These data demonstrated that lncRNA-CCAT1 promoted glioma cell proliferation via inhibiting miR-410, providing a new insight about the pathogenesis of glioma proliferation.

Transforming growth factors β (TGF-β) pathway has been proven to play important roles in oncogenesis and angiogenesis of gliomas. MiR-132 might be related to TGF-β signaling pathway and high miR-132 expression was reported to be a biomarker of poor prognosis in patients diagnosed with glioma. However, the expression regulation way involved in TGF-β pathway and clinical significance of miR-132 have not been investigated in glioma cells. Here we reported that the mRNA level of miR-132 and TGF-β concentration were both increased in patients with brain glioma. Correlation analysis revealed that TGF-β concentration was positively correlated with mRNA level of miR-132. In addition, the mRNA level of miR-132 was up-regulated by TGF-β in a concentration-dependent and time-dependent manner. Furthermore, we found that miR-132 was involved in modulation of the TGF-β signaling pathway and down-regulation of SMAD7 expression by directly targeting the SMAD7 3'-UTR. MiR-132 was negatively correlated with SMAD7 in patients with brain glioma. Taken together, our results suggest that miR-132 could be stimulated by TGF-β and might enhance the activation of TGF-β signaling through inhibiting SMAD7 expression in glioma cells. These findings contribute to a better understanding of the mechanism of the activation of TGF-β signaling by miR-132.