(A) Discovery of additional FINs based on selective lethality in the four BJ cell lines.
(B) FINs (red) are distinct from non-FINs (blue) in accompanying lipid ROS generation during the cell death process and in death suppression by an antioxidant, BHT.
(C) Modulatory profiling (Wolpaw et al., 2011) with erastin, PE, DPI2, DPI10, and other lethal molecules confirmed that PE, DPI2, and DPI10 induced a similar form of cell death as erastin in HT-1080 cells. ΔAUC with a positive sign indicates suppression of cell death, whereas a negative sign indicates sensitization by cell death modulators upon lethal compound treatment.
(D) Inhibition of GPX4 by BSO sensitized cells to death induced by 12 FIN compounds, whereas activation of GPX4 by cDNA overexpression rescued cells from the lethality of FIN compounds.
(E) Eight structurally diverse FIN compounds inhibited GPX4, whereas two FIN compounds, DPI2 and erastin, and the negative control staurosporine (STS), a non-FIN compound, did not show direct GPX4 inhibition in this LC-MS-based assay.
(F) The two FIN compounds, DPI2 and erastin, depleted cellular GSH, which inhibits GPX4 indirectly, whereas staurosporine did not deplete GSH. Bar graph indicates mean ± SD (n = 3).
(G) Model of GPX4-regulated ferroptosis pathway. Ferroptosis inducers can be categorized into two classes based on the mode of GPX4 inhibition. *p < 0.05; ***p < 0.001. See also Figure S5 and Table S3.