Fig. 5. IDH1 mutation reduces GPX4 protein level.
a IDH1R132C mutation and 2-HG treatment accelerate the onset of erastin-induced ferroptosis. HT-1080 cells with indicated genotypes or treatment were treated with erastin (10 μM) for indicated time, and cell viability were assayed by trypan blue staining. b Ferroptosis is a reversible process before reaching a point of no-return. HT-1080(IDH1+/R132C) or HT-1080(IDH1+/−) cells were treated with erastin for 12 h and then erastin was either removed from or kept in the culture medium for additional 8 h, followed by microscopic photograph. c Mutant IDH1 does not enhance ferroptosis in cells treated with GPX4 inhibitor RSL3. HT-1080(IDH1+/R132C) or HT-1080(IDH1+/−) cells were treated with RSL3 (2 μM) for indicated time, and cell viability were assayed by trypan blue staining. d Knocking out of IDH1R132C allele up-regulates the protein level of GPX4. The protein levels of Nrf2, Acsl4, Erk, p-Erk, GPX4, and Actin in HT-1080(IDH1+/R132C) or HT-1080(IDH1+/−) cells were detected by western blot. e D2HGDH overexpression upregulates the protein level of GPX4. The protein level of Acsl4, Flag-D2HGDH, GPX4 and Actin in HT-1080(IDH1+/R132C) cells expressing vector or Flag-D2HGDH were detected by western blot. f D-2-HG treatment down-regulates the protein level of GPX4. The protein level of GPX4 and Actin in HT-1080(IDH1+/−) cells with or without D-2-HG treatment were detected by western blot