In summary, in normal cells, METTL14 mediated the m6A modification and expression of circRNA_103239, which sponging miR-182-5p and inducing the expression of MTSS1, subsequently inhibiting the EMT; whereas in glioma cells, downregulated METTL14 induced downregulated m6A modification and expression of circRNA_103239, further resulting in the up-regulation of miR-182-5p and down-regulation of MTSS1, consequently promoting the EMT of glioma cells and triggering the progression of tumor. Here, MTSS1 is linked to glioma.