ACTA1 and neoplasm: Therefore, immunohistochemical staining of several epithelial markers (cytokeratin‐19 (KRT19), epithelial cell adhesion molecule (EpCAM), laminin, and occludin) and mesenchymal markers (HA receptor CD44, fibronectin, and alpha smooth muscle actin (α‐SMA)) in sectioned B16F10 tumor tissues were performed to determine whether the chosen model tumor entity is sensitive to ferroptotic processes (Figure S7B, Supporting Information).