Transwell Migration Assay

To further determine the migration ability of cells, transwell migration experiments were performed using 24 wells of a transwell plate with 8.0 µm pores (Corning, USA). After the siRNA transfection, cells were resuspended in 200 µL of serum-free medium and then were seeded in the upper chamber. The lower chamber was filled with DMEM with 10% FBS. After incubation at 37°C for 24 h, the cells that invaded through the membrane to the bottom chamber were fixed in 4% paraformaldehyde, which was followed by staining with 0.5% crystal violet. Then, the number of invading cells in the bottom chamber was counted with a microscope (Nikon, Japan).