To our surprise, 3D CRCs exhibited much lower expression of E‐cadherin than 2D cells (Figure S2A, Supporting Information), as it is known to enhance the resistance of tumor cells to ferroptosis.[18] Further, 3D CRCs expressed both epithelial (keratin 5/14/19: KRT5, KRT14, KRT19) and mesenchymal (ZEB1, ZEB2, VIMENTIN) markers (Figure2A–C), especially KRT19 and ZEB2. This evidence concerns the gene KRT19 and neoplasm.