Upregulation of hsa-miR-196a-5p is associated with MIR196A2 methylation and affects the malignant biological behaviors of glioma.

Hsa-miR-196a-5p is involved in tumorigenesis and progression. However, the driving factors for hsa-miR-196a-5p overexpression and its correlation with the clinicopathological features and prognosis of patients remain unclear in glioma. Thus, this study aimed to investigate the prognostic value of hsa-miR-196a-5p and its correlation with MIR196A2 methylation in glioma. We observed that hsa-miR-196a-5p expression was upregulated in glioma. Next, 112 patients were divided into high (n = 56) and low (n = 56) hsa-miR-196a-5p expression groups. The chi-square test showed that hsa-miR-196a-5p expression was significantly related to age, WHO grade, histopathology, IDH mutation status, and 1p/19q codeletion. Univariate and multivariate Cox regression analyses showed that hsa-miR-196a-5p expression was an independent prognostic factor. GO and KEGG enrichment analyses showed that hsa-miR-196a-5p may be involved in the MAPK signaling, focal adhesion and cancer-related pathways. Compared with the normal astrocyte cell line, glioma cell lines had an unregulated MIR196A2 methylation level, which was confirmed by TCGA data. The hypermethylated CpG sites of MIR196A2 were mainly concentrated in the gene body region, which was significantly associated with hsa-miR-196a-5p overexpression. Kaplan-Meier curves revealed that MIR196A2 hypermethylation was a poor prognostic factor. These findings suggest that hsa-miR-196a-5p overexpression may be involved in malignant biological behaviors, and MIR196A2 hypermethylation of the gene body was significantly associated with hsa-miR-196a-5p overexpression, which was a poor prognostic factor of glioma. Therefore, MIR196A2 hypermethylation may act as an early marker of prognosis of patients with glioma.