Research progress on the mechanism of epithelial mesenchymal transformation in RPE cells and the treatment of PVR

Proliferative vitreoretinopathy(PVR)is a serious complication arisen from ocular trauma, diabetic retinopathy, vascular retinopathy, inflammatory retinopathy and other ocular diseases. It is also the most important reason for the failure of rhegmatogenous retinal detachment surgery, which is a great threat of visual function. A large number of studies have proved that the main risk factor for PVR is the damage of blood-retinal barrier, in which retinal pigment epithelial(RPE)cells are stimulated by cytokines in the vitreous cavity. RPE cells underwent epithelial-mesenchymal transition(EMT), which transformed into fibroblasts. The cell morphology changed, the tight junctions between cells disappeared, the cell polarity lost, and the proliferation, migration, and invasion abilities were enhanced. A contractile fibrous proliferative membrane is formed on the anterior surface or under the retina. The fibrous proliferative membrane will lead to the retina folds, pull the retina and lead to retinal detachment, which will eventually lead to vision loss or even blindness. Nowadays, plenty of studies investigating the prevention and treatment of PVR have been carried out at home and abroad. In this review, we briefly illustrated the signaling pathways related to epithelial-mesenchymal transformation in RPE cells and the treatment of PVR