Transwell-Based Migration and Invasion Assays

The migration and invasion assays were performed using 8-μm Transwell chambers (Corning Life Science, Tewksbury, MA, USA). The cells (1×10⁴ cells/well) were pretreated with BAY117082 (15 μM) and were loaded onto the upper chamber with 200 μL of serum-free RPMI 1640 medium. The lower chambers contained 500 μL of RPMI 1640 with 2.5% FBS, with or without 100 ng/mL SDF-1. The cells in the chambers were incubated for 24 h at 37°C. The cells could migrate through the membrane for the migration assay and through a matrigel-coated membrane for the invasion assay (Corning Life Science, Tewksbury, MA, USA). Nonmigrated cells were removed from the upper surface of the chamber with a wet cotton swab, and the cells on the lower surface of the chamber were stained using the Wright-Giemsa method as described previously [16 (link)]. At least 4 randomly selected fields were counted, and the average number from these 4 counts is presented.