Transwell invasion and migration assays for the assessment of bladder cancer cell invasive and migratory abilities

The bladder cancer cell invasive and migratory capacities were evaluated using Transwell invasion and migration assays. Briefly, the treated cells were suspended in FBS-free DMEM and seed onto the upper chamber with Matrigel-coated transwell inserts (for cell invasion assay; 8 µm pore size, Millipore) or without Matrigel-coated transwell inserts (For cell migration assay, 8 µm pore size). The lower chamber was filled with full medium (served as the chemo-attractant). With a further culturing for 24 h, the invaded or migrated cells were fixed with 50% methanol followed by staining with 0.5% crystal violet at room temperature for 10 min. The number of invaded and migrated cells were assessed under a light microscope by randomly selecting five fields.