Long non-coding RNA LINC00346 regulates proliferation and apoptosis by targeting miR-128-3p/SZRD1 axis in glioma

OBJECTIVE: Long non-coding RNAs (IncRNAs) participate in multiple processes of malignant tumors, including glioma. In this study, we aimed to explore the effect of LINC00346 on glioma and its underlying mechanism. MATERIALS AND METHODS: The Cancer Genome Atlas (TCGA) and the Chinese Glioma Genome Atlas (CGGA) databases were used to analyze the expression patterns and survival risk of LINC00346, miR-128-3p and SUZ RNA binding domain containing 1 (SZRD1) in glioma tissues. The binding sites were predicted by bioinformatic databases, and then, validated by Dual-Luciferase assay and RNA immunoprecipitation (RIP). qRT-PCR and Western blot were performed to evaluate the gene expression levels. CellTiter-Gle and colony formation assays were used to detect the proliferation of glioma cells. Flow cytometric analysis was used to evaluate the apoptosis of glioma cells. The xenograft models were established to investigate the impact of LINC00346 on tumor growth in vivo. RESULTS: We found that both LINC00346 and SZRD1 expression were negatively related to the poor overall survival rate in glioma patients. However, miR-128-3p showed the opposite effect of survival outcomes. LINC00346 knockdown remarkably restrained cell proliferation both in vitro and in vivo, as well as inducing apoptosis by acting as a molecular sponge of miR-128-3p. Moreover, miR-128-3p bound to SZRD1 3'-UTR in a sequence-specific manner. In addition, LINC00346 knockdown significantly inhibited the expression of SZRD1 and the inhibition could be reversed by miR-128-3p mimics. Furthermore, cell proliferation and apoptosis affected by LINC00346 were partially rescued by modulating miR-128-3p or SZRD1 expression. CONCLUSIONS: LINC00346/miR-128-3p/SZRD1 axis played a crucial role in modulating the malignant progression of glioma, which may serve as a prognostic indicator and a probable therapeutic target for glioma.