lncRNA TTN-AS1 upregulates RUNX1 to enhance glioma progression via sponging miR-27b-3p

Long non-coding RNAs (lncRNAs) contribute to the tumorigeneses of numerous types of cancer, including glioma. The present study was designed to unveil a novel lncRNA functioning in glioma and explore the underlying mechanisms. lncRNA titin-antisense RNA1 (TTN-AS1), miR-27b-3p and Runt-related transcription factor 1 (RUNX1) expression in glioma tissues and cell lines was estimated by RT-qPCR. Si-TTN-AS1 was transfected into glioma cell lines (U251 and LN229), and CCK-8 assay, flow cytometry, wound healing and Transwell assays were applied to estimate the function of TTN-AS1 in glioma cells. miR-27b-3p inhibitor was used to explore the mechanisms. The results revealed that TTN-AS1 was highly expressed in glioma specimens and cell lines. Downregulation of TTN-AS1 inhibited the proliferation, migration and invasion of the glioma cells, as well as increased the rate of apoptosis.In vivo, the tumor growth was also inhibited by TTN-AS1 depletion in nude mice. Furthermore, we revealed that TTN-AS1 exerted oncogenic effects via sponging miR-27b-3p and thereby positively regulating RUNX1 expression. In conclusion, the present study supported that TTN-AS1 acts as an oncogene in glioma by targeting miR-27b-3p to release RUNX1. This finding may contribute to gene therapy of glioma.