SLC7A11 and neoplasm: We further confirmed by western blotting that IKE-treated TIPE2−/− tumor MDSCs profoundly enhanced the key ferroptosis defense proteins SLC7A11 and GPX4, but immensely lowered the main lipid peroxidation trigger protein ACSL4 when compared to IKE-treated WT tumor MDSCs (Figure 2e and Figure S2).