To unveil the underlying mechanism, Kirill Bersuker used a synthetic lethal CRISPR–Cas9 screen to distinguish genes in U‐2 OS osteosarcoma cells treated with a GPX4 inhibitor,62 and Sebastian Doll generated a cDNA expression library derived from an MCF7 ferroptosis‐resistant cell line and screened for genes complementing loss of GPX4.63 Coincidentally, they simultaneously found that ferroptosis suppressor protein 1(FSP1) is an important ferroptosis suppressor that parallels GPx4. This evidence concerns the gene AIFM2 and osteosarcoma.