CDH1 and cancer: Molecular tumor biology discusses the epithelial‐to‐mesenchymal transition (EMT) as the onset of cancer cells becoming motile in carcinoma.[10, 11] However, cancer cells do not show a clear, complete transition; instead, they assume a spectrum of transitional states[12, 13, 14] and E‐cadherin is even required for metastasis in multiple breast cancer models.[15] Thus, a molecular state defining cell motility has not yet been found.