Epithelio-Mesenchymal Transition (EMT) has been recognised over the past two decades as an essential, highly regulated, and often-employed mechanism in normal embryological development, used as a prelude to migration of epithelial-derived cells in morphogenesis. Suggestions that EMT may also play an important role in carcinoma metastasis have recently matured, with high-level reports documenting the progression-like consequences of EMT in various cancer systems. Even more recently, the production of fibroblastoid cells from epithelial precursors in fibrotic diseases has been recognised as bearing the hallmarks of EMT.

The biological and clinical importance of EMT has now achieved recognition.