MiR-32 Inhibits Proliferation and Metastasis by Targeting EZH2 in Glioma

Glioma is identified as a broad category of brain and spinal cord tumors. MiR-32 is important in regulating the genesis of different cancers; however, the underlying mechanisms of miR-32 in glioma still largely unknown. This study aimed to elucidate pathobiological functions of miR-32 in glioma and verify its effect on the regulation of enhancer of zeste homolog 2.

The expression of miR-32 and enhancer of zeste homolog 2 was detected by quantitative real-time polymerase chain reaction and Western blot in glioma tissues and cells. Cell Counting Kit-8 (CCK-8) assay was used to examine the effects of miR-32 on human glioma cells proliferation. Transwell assay was used to examine cell metastasis, respectively. Two bioinformatics analysis software and luciferase reporter assay were chosen to confirm targeting association between miR-32 and enhancer of zeste homolog 2.

MiR-32 was downregulated in glioma tissues and cells. Furthermore, enhancer of zeste homolog 2 expression was upregulated and negatively correlated with miR-32 in clinical tissues. Ectopic expression of miR-32 inhibited glioma cell proliferation, migration, and invasion. Enhancer of zeste homolog 2 was identified as direct target gene of miR-32 in glioma. Overexpression of enhancer of zeste homolog 2 ablated the inhibitory effects of miR-32.

In summary, our finding suggests that miR-32 acts an important role in inhibiting glioma cell proliferation and metastasis and suppresses the expression of ABCC4 by directly targeting its 3'-untranslated region. The miR-32/enhancer of zeste homolog 2 axis may provide new insights to the treatment for glioma.