SMAD4 and mesenchymal cell neoplasm: In order for our CRC cell line models of Snail1-HA-inducible, SMAD4-independent EMT execution to be applicable to human cancer, not only would the EMT-associated gene expression be expected to be independent of SMAD4, but also the expression of EMT-TFs should be increased in mesenchymal tumor samples regardless of SMAD4 status.