title: Lysophosphatidic acid induces YAP-promoted proliferation of human corneal endothelial cells via PI3K and ROCK pathways.
abstract: The first two authors contributed equally to this work.Silence of p120-catenin has shown promise in inducing proliferation in human corneal endothelial cells (HCECs), but there is concern regarding off-target effects in potential clinical applications. We aimed to develop ex vivo expansion of HCECs using natural compounds, and we hypothesized that lysophosphatidic acid (LPA) can unlock the mitotic block in contact-inhibited HCECs via enhancing nuclear translocation of yes-associated protein (YAP). Firstly, we verified that exogenous YAP could induce cell proliferation in contact-inhibited HCEC monolayers and postconfluent B4G12 cells. In B4G12 cells, enhanced cyclin D1 expression, reduced p27(KIP1)/p21(CIP1) levels, and the G1/S transition were detected upon transfection with YAP. Secondly, we confirmed that LPA induced nuclear expression of YAP and promoted cell proliferation. Moreover, PI3K and ROCK, but not ERK or p38, were required for LPA-induced YAP nuclear translocation. Finally, cells treated with LPA or transfected with YAP remained hexagonal in shape, in addition to unchanged expression of ZO-1, Na/K-ATPase, and smooth muscle actin (SMA), suggestive of a preserved phenotype, without endothelial-mesenchymal transition. Collectively, our findings indicate an innovative strategy for ex vivo cultivation of HCECs for transplantation and cell therapy.
authors.affiliation: Limbal Stem Cell Laboratory, Department of Ophthalmology, Chang Gung Memorial Hospital , Linkou, Taiwan ; Center for Tissue Engineering, Chang Gung Memorial Hospital , Linkou, Taiwan.
authors.forename: Yi-Jen
authors.initials: YJ
authors.lastname: Hsueh
authors.affiliation: Limbal Stem Cell Laboratory, Department of Ophthalmology, Chang Gung Memorial Hospital , Linkou, Taiwan ; Center for Tissue Engineering, Chang Gung Memorial Hospital , Linkou, Taiwan ; Department of Medicine, College of Medicine, Chang Gung University , Taoyuan, Taiwan.
authors.forename: Hung-Chi
authors.initials: HC
authors.lastname: Chen
authors.affiliation: Department of Physiology, College of Medicine, Chang Gung University , Taoyuan, Taiwan.
authors.forename: Sung-En
authors.initials: SE
authors.lastname: Wu
authors.affiliation: Limbal Stem Cell Laboratory, Department of Ophthalmology, Chang Gung Memorial Hospital , Linkou, Taiwan.
authors.forename: Tze-Kai
authors.initials: TK
authors.lastname: Wang
authors.affiliation: Department of Physiology, College of Medicine, Chang Gung University , Taoyuan, Taiwan.
authors.forename: Jan-Kan
authors.initials: JK
authors.lastname: Chen
authors.affiliation: Limbal Stem Cell Laboratory, Department of Ophthalmology, Chang Gung Memorial Hospital , Linkou, Taiwan ; Center for Tissue Engineering, Chang Gung Memorial Hospital , Linkou, Taiwan ; Department of Chinese Medicine, College of Medicine, Chang Gung University , Taoyuan, Taiwan.
authors.forename: David Hui-Kang
authors.initials: DH
authors.lastname: Ma