Wound healing assay and transwell migration assay

To measure the effect of IDH2 on cell migration, a wound healing assay was performed. Briefly, cells were seeded into 6-well plates and incubated until they were 100% confluent. The confluent monolayer of cells was scratched with a plastic apparatus to create a cell-free clear zone, about 1 mm in width. Then, the cells were washed with PBS and replenished with fresh culture medium. Cells were incubated for 0 h, 24 h or 48h, and the wound distance was measured regularly.

For the transwell migration assay, 15,000 K-1 cells or 20,000 BCPAP cells were added into the top chamber of the insert well (8 μm pore size; Corning, USA) with 200 μl serum-free medium for 10 h or 12 h. After removal of the non-migrating cells in the top chamber, the remaining cells were fixed with 4% paraformaldehyde for 20 min, stained with 0.5% crystal violet for 15 min and counted.