Epithelial-mesenchymal transition（EMT） describes the phenomenon that epithelial cells acquire some characters of mesenchymal cells, such as the loss of polarity, the change of the cytoskeleton protein, appearance of fibroblasts. It plays important roles in many physiological and pathological processes. In recent years, the studies in the biological function of EMT are expanded around such aspects: Embryonic development, wound healing, visceral fibrosis and the occurrence and development of cancer. Therefore, this paper will review the biological function of EMT in these aspects above, so as to prepare for the further study, and provide a new perspective for the diagnosis and treatment for some certain diseases.
