Although we have shown here an alternative pathway by which DACH1 regulates SNAI1 to bring about suppression of EMT and metastasis in breast cancer, the exact domains of DACH1 and SNAI1 involved in the DACH1–SNAI1 interaction, and whether there are other molecules involved in the interaction between DACH1 and SNAI1, remain unknown at this stage. This evidence concerns the gene SNAI1 and breast cancer.