Fig. 8. Erastin induces ferroptosis in tumor-initiating cells and reduces tumor number and mass in vivo.

(a) 3000 FT^stem and FT^t cells were treated with indicated doses of erastin and cell viability assessed 48 hours later. (b) FT^t cells were treated for 48 hrs with 2 μM of erastin alone, the combination of 2uM erastin plus 2 μM ferrostatin-1, the combination of 2uM erastin plus 50 uM DFO, ferrostatin alone, or DFO alone and cell viability assessed. (c,d) Mice were injected intraperitoneally with FT^t cells and treated for 18 days with either vehicle or 20 mg/kg erastin. The number of tumors/mouse and total tumor mass/mouse were measured in the vehicle-treated group (n=5) and in the group treated with erastin (n=6).