For the mice experiments, although we standardized the tumor volume at the start of drug injection to some extent, the tumors in the 2D sgECAD vehicle group after 14 days were still much smaller than those in the 2D Ctrl vehicle group and the tumors in the 2D sgECAD group reached the size for drug injection about one week later than in the control groups (Figure S15C, Supporting Information), suggesting that E‐cadherin deficiency suppresses the growth of 2D cells in vivo. This evidence concerns the gene CDH1 and neoplasm.