miRNA-429 Inhibits Astrocytoma Proliferation and Invasion by Targeting BMI1

Glioblastoma multiforme (GBM), the most common primary brain cancer in adults, is usually the most lethal type of brain tumor. MicroRNAs (miRNAs) are a class of small, non-coding RNA molecules that deeply involves with the regulation of gene expression and cellular processes, including proliferation, apoptosis, migration and invasion. The objective of the study is to investigate the effect of miRNA-429 on human glioblastoma tissues and cell lines. miRNA-429 expressions in human glioblastoma, normal brain tissue samples, and human malignant glioma cell lines (U87, U251 and LN229) were compared using reverse transcription-quantitative PCR and western blot methods. U251 cell lines were transfected with miRNA-429 mimics, and then the effects of miRNA-429 on cell proliferation and invasion were investigated by CCK8 and Transwell invasion assay, respectively. It was found that miRNA-429 expression was significantly reduced in the examined Glioblastoma samples and human glioma cell lines. Overexpression of miRNA-429 inhibited Glioblastoma cell proliferation and invasion. Additionally, the present study also showed that BMI1 was a functional target of miRNA-429. Overexpression of BMI1 undermined the inhibition effect of miRNA-429 in glioblastoma and U251 cell lines. The current study demonstrated that miRNA-429, as a tumor suppressor gene, was capable of negatively regulating the expression of BMI1 in U251 cells.