CircSKA3 Downregulates miR-1 Through Methylation in Glioblastoma to Promote Cancer Cell Proliferation

BACKGROUND: Circular RNA circSKA3 plays an oncogenic role in breast cancer, while its role in glioblastoma (GBM) is unknown. This study aimed to explore the role of circSKA3 in GBM. METHODS: Differential expression of circSKA3 and miR-1 in GBM and adjacent non-cancer tissue samples were analyzed by RT-qPCR. GBM cells were transfected with circSKA3 expression vector or miR-1 mimic, followed by RT-qPCR to explore the potential crosstalk between them. Methylation-specific PCR (MSP) was carried out to assess the role of circSKA3 in regulating the methylation of miR-1 gene. The role of circSKA3 and miR-1 in regulating GBM cell proliferation was analyzed by CCK-8 assay. RESULTS: We found that circSKA3 was upregulated in GBM and inversely correlated with miR-1 across GBM tissues. High expression levels of circSKA3 and low expression levels of miR-1 were significantly correlated with the poor survival of GBM patients. In GBM cells, overexpression of circSKA3 increased the methylation of miR-1 gene and decreased the expression of miR-1. CCK-8 assay showed that overexpression of circSKA3 reduced the inhibitory effects of miR-1 on cell proliferation. CONCLUSION: Therefore, circSKA3 may downregulate miR-1 through methylation in GBM to promote cancer cell proliferation.