MiR-454-3p Exerts Tumor-suppressive Functions by Down-regulation of NFATc2 in Glioblastoma

Glioblastoma (GBM) is the most prevalent and malignant primary brain tumor. Numerous studies have demonstrated that aberrant microRNAs (miRNAs) expression is involved in various pathogenesis events in GBM. miR-454-3p has been found to be downregulated in GBM, however, the role and underlying mechanism has not been fully investigated. The expression levels of miR-454-3p in GBM clinical tissues and cultured cell lines were measured by qRT-PCR. To evaluate the role of miR-454-3p in GBM, GBM cells were transfected with miR-454-3p inhibitor (anti-miR-454-3p)/control inhibitor (anti-miR-NC) or miR-454-3p mimic/control mimic (miR-NC). Online prediction algorithm Targetscan was used to predict the target genes of miR-454-3p. The dual luciferase reporter gene assay was performed to confirm whether nuclear factor of activated T cells c2 (NFATc2) was a direct biological target of miR-454-3p. We found that miR-454-3p expression was significantly decreased in both GBM tissues and cultured cell lines. Overexpression of miR-454-3p by transfection with miR-454-3p mimic suppressed cell proliferation and induced apoptosis of GBM cells. Nuclear factor of activated T cells c2 (NFATc2) was predicted as a target gene of miR-454-3p. We found that NFATc2 expression was significantly increased in both GBM tissues and cultured cell lines. Besides, expression levels of miR-454-3p were negatively associated with NFATc2 expression in GBM tissues. NFATc2 knockdown in GBM cells obviously inhibited cell proliferation and elevated apoptosis. Luciferase reporter assay revealed that NFATc2 was a target gene of miR-454-3p. miR-454-3p overexpression suppressed the NFATc2 expression, while inhibition of miR-454-3p induced the NFATc2 expression. Suppression of NFATc2 blocked the effects of miR-454-3p inhibitor on cell proliferation and apoptosis in GBM cells. The results indicated that miR-454-3p executed the tumor suppressive activity via downregulating NFATc2 in GBM.