Transwell Migration and Invasion Assay

Transwell migration and invasion assays were performed according to the previous publication (17 (link)). For the invasion assay, Matrigel (Solarbio) was pre-coated in the upper Transwell chamber, and the SW480 and SW620 cells were inoculated into the upper Transwell chamber (BD, CA, USA) (approximately 1×10⁵/well) with 200 µL of serum-free medium. Six hundred microliters of medium containing 20% FBS was added to the lower chamber. The chamber was removed after incubation at 37 ℃ for 36 h, and the cells were fixed with 4% paraformaldehyde (Solarbio) for 30 min, then stained with 0.1% crystal violet (Solarbio) for 15 min. The cells on the internal surface of the chamber were gently wiped off. Finally, the migrating or invading cells were observed and counted in five randomly fields under an Olympus inverted microscope (Olympus, Tokyo, Japan).