MicroRNA-664 regulates cell invasion and migration and epithelial-mesenchymal transition by targeting TGF-β signal in glioblastoma

This study aimed to investigate the effects of miR-664 on glioblastoma cell invasion and migration and to reveal its possible molecular mechanisms. The expression of miR-664 was measured by quantitative real-time PCR (qRT-PCR) in glioblastoma tissue and the normal brain tissue as well as in two human glioblastoma cell lines. Additionally, the expression of transforming growth factor beta receptor II (TGFBR2) was detected by qRT-PCR and western bolt. The effect of miR-664 on glioblastoma cell invasion and migration were studied by transwell assay. The epithelial-mesenchymal transition (EMT)-related protein (N-cadherin, E-cadherin and vimentin) expression was detected by Western bolt. Furthermore, the miR-664 target was searched and the underlying mechanism was clarified by reporter assay. The result showed that miR-664 expression was inhibited while TGFBR2 expression was upregulated in glioblastoma tissue and cell lines. Overexpression of miR-664 suppressed glioblastoma cell invasion and migration, promoted E-cadherin expression, and inhibited expressions of N-cadherin and vimentin. Further study showed that TGFBR2 was the direct target of miR-664 and miR-664 overexpression regulated cell invasion and migration via TGF-beta signal. The data indicated that miR-664 may suppress tumor invasion and migration by targeting TGF-beta signal and regulate EMT progress of glioblastoma cells.