The Regulation of Epithelial Mesenchymal Transition in Ocular Disorders.

Epithelial-mesenchymal transition (EMT) is a process which in epithelial cells lose their character and acquire mesenchymal phenotypes. EMT is associated with inflammation and wound healing; however, aberrant EMT causes fibrosis by disreconstruction of injured tissue and deposition of overproduced extracellular matrix. The adhesion switch from cell-cell contact to cell-extracellular matrix contact occurs during the process of EMT. We found that integrin-associated extracellular matrices induced EMT-like phenomenon via paxillin activation in trabecular meshwork cells. In addition, we discovered that tumor necrosis factor-α is a key EMT inducing factor and hyaluronan receptor CD44 and ERM protein family regulate the induction and maintenance of EMT in retinal pigment epithelial cells. We think that developing drugs based on the concept of EMT may become a new therapy which leads to re-acquisition of epithelial characters and their function in damaged tissues