Methionine depletion inhibits hepatocellular carcinoma by inducing ferroptosis and suppressing epithelial-mesenchymal transition through the ARNT2/UBE2Z pathway

Figure 1 Methionine deficiency promotes hepatocellular carcinoma cell ferroptosis. A and B: Intracellular methionine and S-adenosylmethionine levels were determined using ELISA assay; C and D: ACSL4 and GPX4 levels were examined by western blot; E: Cell proliferation activity was assessed using the CCK-8 assay; F: Reactive oxygen species levels were measured using the fluorescent probe DCFH-DA; G: Intracellular lipid peroxidation was evaluated using the malondialdehyde assay kit; H: Intracellular glutathione levels were determined using the glutathione colorimetric assay. Erastin (a ferroptosis inducer, 10 μm, 24 hours), ferrostatin-1 (Fer-1, a potent and selective inhibitor of ferroptosis, 2 μm, 24 hours), necrostatin-1 (Nec-1, a potent necroptosis inhibitor that crosses the blood-brain barrier, 60 μm, 24 hours), and Z-VAD-FMK (a pan-caspase inhibitor, 50 μm, 24 hours) were used. Results are presented as the mean ± SD, n = 3. ^aP < 0.05; ^bP < 0.01; ^cP < 0.001. Met: Methionine; SAM: S-adenosylmethionine; Met-: Methionine-deficient; Met+: Methionine-supplemented (100 μm); GSH: Glutathione; MDA: Malondialdehyde; NS: Not significant.