Purpose: Glioma causes significant mortality worldwide. The currently available treatment strategies are flawed and the therapeutic targets are limited. Accumulating evidence suggests that microRNAs (miRs) are involved in the development and progression of different cancers. Herein, the therapeutic potential of miR-9 was explored in human glioma cells.
Methods: The qRT-PCR was used for expression analysis. WST-1 assay was used for determination of cell viability. Acridine orange (AO) / ethidium promide (EB) and annexin V/propidium iodide (PI) were used for the detection of apoptosis. Flow cytometry was used for cell cycle analysis. Wound healing and transwell assays were used to monitor cell migration and invasion. Protein expression was determined by western blot analysis.
Results: The results showed that miR-9 is significantly downregulated in glioma cells. Overexpression of miR-9 caused significant inhibition in the proliferation of U87 glioma cells. The miR-9-triggered growth inhibition was mainly due to the induction of apoptosis which was concomitant with increase in the Bax/Bcl-2 ratio. Overexpression of miR-9 also induced arrest of U87 glioma cells at G2/M checkpoint of cell cycle. Additionally, transwell and wound healing assays showed that miR-9 caused significant decrease in the migration and invasion of U87 glioma cells. Bioinformatics analysis showed that miR-9 exerts its effects by inhibiting Cadherin-1 (CDH1). However, overexpression of CDH1 could nullify the effects of miR-9 on the growth, migration and invasion of glioma cells.
Conclusion: Taken together, miR-9 may exhibit therapeutic implications in the treatment of glioma.