Transwell Migration/Invasion Assay

For the migration assay, 5×10⁴ cells in 200 µL of the serum-free medium were seeded in the 8-mm poresize the upper compartment of the chamber in 24-well cell culture insert companion plates. Then, 600 µL of complete medium containing 10% FBS was added into the lower chamber. After incubation for another 12 hours, the chambers were removed and the cells on the upper surface of membrane were wiped off with cotton swabs, and the migrated cells on the lower surface were stained with 0.5% crystal violet for 30 minutes. Finally, the cells were observed with an inverted microscope, and images were obtained. For the invasion assay, 1×10⁵ of the cells were seeded to the upper surface of polycarbonate membranes and covered with the 50 µL Matrigel (Becton-Dickinson) layer. The invasion assay was incubated for another 48 hours and subsequent procedures were similar to the migration assay.