GPX4 and breast cancer: We also observed that SB-T-101141 markedly promoted iron and ferrous ion levels, intracellular iron accumulation, and increased MDA level, which were significantly attenuated by DFOM (Figs. 5D–G and S5G), marked with reduced GSH level (Fig. 5H), but no effect of GPX4 expression in Paclitaxel-resistant breast cancer cells (Fig. S5H).