GPX4 and triple-negative breast carcinoma: In addition, Hou and his colleagues revealed that metformin could induce ferroptosis in the triple-negative breast cancer (TNBC) cell line MDA-MB-231 via upregulation of miR-324-3p, which directly interacted with the 3’ untranslated region (UTR) of glutathione peroxidase 4 (GPX4) and further inhibited GPX4 (Figure 5) [82].