Transwell Migration and Invasion Assay

HCT 116 and SW620 cell migration was evaluated by Costar Transwell inserts (Corning, USA) and invasion by Matrigel Invasion Chambers (BD, USA) [25 (link),26 (link)]. For migration assay, transfected cells were serum-starved and then seeded (1× 10⁴ cells per well) onto transwell membranes with serum-free RPMI-1640 medium or L-15 Medium. Lower chambers of companion plates were enriched with 10% FBS medium as a chemoattractant. Incubated for 24 h at 37°C, non-migrated cells on inner surfaces were scrapped, whereas migrated cells were fixed, washed and stained. Five fields were imaged using the Microscopes and Imaging Systems (Leica Microsystems, USA) from each transwell membrane, and the number of migrated cells was counted. As for invasion assays, Matrigel Invasion Chambers was used and performed as migration assay, except for the incubation time was 36 h.