Figure 4. Metallothionein (MT)-1G is a negative regulator of ferroptosis in hepatocellular carcinoma (HCC) cells.

(A) Indicated HCC cells were treated with sorafenib (5 µM) and erastin (10 µM) with or without cell death inhibitors (ferrostatin-1, 1 µM; liprostatin-1, 100nM; ZVAD-FMK,10 µM; necrosulfonamide, 0.5 µM) for 24 hours and cell viability was assayed (n=3, *p < 0.05 versus sorafenib or erastin treatment group). (B) Indicated HCC cells were treated with apoptosis inducer staurosporine (0.5 µM) or necroptosis inducer (ZVAD-FMK [10 µM]/TNFα (10 ng/ml) with or without ZVAD-FMK (10 µM) and necrosulfonamide (0.5 µM) for 24 hours and cell viability was assayed (n=3, *p < 0.05). (C) Indicated HCC cells were treated with erastin (10 µM) or sorafenib (5 µM) for 24 hours. The levels of malondialdehyde (MDA), Fe²⁺, indicated gene mRNA, and glutathione (GSH) levels were assayed (n=3, *p < 0.05 versus control shRNA group). (D) Indicated HCC cells were treated with erastin (10 µM) or sorafenib (5 µM) with or without all-trans retinoic acid (ATRA) (1 µM), trigonelline (0.5 µM), brusatol (40 nM), or propargylglycine (PPG) (2 mM) for 24 hours. The levels of MDA and GSH were assayed (n=3, *p < 0.05 versus sorafenib or erastin treatment group).