lncRNA C2dat1 Promotes Cell Proliferation, Migration, and Invasion by Targeting miR-34a-5p in Osteosarcoma Cells.

Osteosarcoma is a highly aggressive malignant bone tumor with poor prognosis. Evidence has suggested that lncRNAs are deregulated in multiple cancers. In this study, we investigated the role of the lncRNA C2dat1 on the biological functions of osteosarcoma cells. The expressions of C2dat1, miR-34a-5p, and Sirt1 in human osteosarcoma cells were altered by transfection with their specific vectors/shRNA or mimic/inhibitor. Cell viability, migration, invasion, and apoptosis were assessed posttransfection. The mRNA and protein levels of C2dat1, miR-34a-5p, and Sirt1 were detected by qRT-PCR and Western blot. The results showed that C2dat1 suppression reduced cell viability, invasion, and migration, whereas it increased cell apoptosis in OS-732 cells. The expression of miR-34a-5p was downregulated when C2dat1 was overexpressed, whereas it negatively regulated Sirt1 expression. miR-34a-5p overexpression inhibited cell viability, migration, and invasion and promoted cell apoptosis in osteosarcoma cells by downregulation of Sirt1. Furthermore, miR-34a-5p overexpression deactivated the p38/ERK/AKT and Wnt/β-catenin signaling pathways by inhibition of Sirt1.