Fig. 1: 4EGI-1 and 4E1RCat act as ferroptosis inhibitors.
From: A noncanonical function of EIF4E limits ALDH1B1 activity and increases susceptibility to ferroptosis
a Flow chart of our screening strategy. b Cell viability of HT-1080 cells following treatment with RSL3 (0.5 μM) in the absence or presence of 4EGI-1 (10, 5, 2.5, 1.25 μM) or 4E1RCat (10, 5, 2.5, 1.25 μM) for 24 h. Mean ± SD, n = 3. c Cell viability of HT-1080 cells following treatment with RSL3 (0.5 μM), erastin (5 μM), ML162 (0.5 μM), ML210 (5 μM), FIN56 (2.5 μM), or FINO2 (10 μM) in the absence or presence of 4EGI-1 (10 μM) or 4E1RCat (10 μM) for 24 h. Mean ± SD, n = 3. d The accumulation of iron in HT-1080 and Calu-1 cells treated with RSL3 (0.5 μM) or erastin (5 μM) in the absence or presence of 4EGI-1 (10 μM) or 4E1RCat (10 μM) for 24 h. Mean ± SD, n = 3. e The accumulation of lipid hydroperoxides in HT-1080 and Calu-1 cells treated with RSL3 (0.5 μM, 4 h) or erastin (5 μM, 6 h) in the absence or presence of 4EGI-1 (10 μM) or 4E1RCat (10 μM). Mean ± SD, n = 3. f, g The antioxidant activity of the indicated compounds (10 μM) was analyzed by a 2,2-diphenyl-1-picrylhydrazyl (DPPH) or FENIX (STY-BODIPY) assay. Mean ± SD, n = 4; one-way ANOVA with Tukey’s multiple comparisons test. h The iron chelator activity of the indicated compounds (40 μM) was analyzed by using the ferrozine Fe2+ binding assay. Mean ± SD, n = 3; one-way ANOVA with Tukey’s multiple comparisons test. i, j Cell viability and intracellular glutathione (GSH) level of Calu-1 cells following treatment with RSL3 (0.5 μM) or erastin (5 μM) in the absence or presence of 4EGI-1 (10 μM), 4E1RCat (10 μM), or ferrostatin-1 (Fer-1, 1 μM) for 72 h. Mean ± SD, n = 3; two-way ANOVA with Tukey’s multiple comparisons test. k Immunoprecipitation (IP) analysis of EIF4E-binding proteins in Calu-1 cells following treatment with 4EGI-1 (10 μM) or 4E1RCat (10 μM) for 24 h. IB immunoblot. Mean ± SD, n = 3; one-way ANOVA with Tukey’s multiple comparisons test.
