Department of Anatomy, Histology and Embryology, Fudan University, Shanghai, PR China.
Department of Pathology and Laboratory Medicine, University of Tennessee Health Science Center, Memphis, TN, 38163, USA.
Biochem Biophys Res Commun. 2018 Apr 6;498(3):573-578. doi: 10.1016/j.bbrc.2018.03.021. Epub 2018 Mar 6.
Proliferative vitreoretinopathy (PVR) is a common complication of open globe injury and the most common cause of failed retinal detachment surgery. The response by retinal pigment epithelial (RPE) cells liberated into the vitreous includes proliferation and migration; most importantly, epithelial to mesenchymal transition (EMT) of RPE plays a central role in the development and progress of PVR. For the first time, we show that knockdown of BIRC5, a member of the inhibitor of apoptosis protein family, using either lentiviral vector based CRISPR/Cas9 nickase gene editing or inhibition of survivin using the small-molecule inhibitor YM155, results in the suppression of EMT in RPE cells. Knockdown of survivin or inhibition of survivin significantly reduced TGFβ-induced cell proliferation and migration. We further demonstrated that knockdown or inhibition of survivin attenuated the TGFβ signaling by showing reduced phospho-SMAD2 in BIRC5 knockdown or YM155-treated cells compared to controls. Inhibition of the TGFβ pathway using TGFβ receptor inhibitor also suppressed survivin expression in RPE cells. Our studies demonstrate that survivin contributes to EMT by cross-talking with the TGFβ pathway in RPE cells. Targeting survivin using small-molecule inhibitors may provide a novel approach to treat PVR disease.
增殖性玻璃体视网膜病变(PVR)是开放性眼球损伤的常见并发症,也是视网膜脱离手术失败的最常见原因。视网膜色素上皮(RPE)细胞释放到玻璃体内的反应包括增殖和迁移;最重要的是,RPE 的上皮间质转化(EMT)在 PVR 的发展和进展中起着核心作用。我们首次表明,使用基于慢病毒载体的 CRISPR/Cas9 切口酶基因编辑或使用小分子抑制剂 YM155 抑制生存素,敲低凋亡蛋白家族成员 BIRC5,可导致 RPE 细胞中 EMT 的抑制。敲低生存素或抑制生存素可显著降低 TGFβ 诱导的细胞增殖和迁移。我们进一步证明,通过与对照组相比,在 BIRC5 敲低或 YM155 处理的细胞中磷酸化 SMAD2 减少,敲低或抑制生存素可减弱 TGFβ 信号。使用 TGFβ 受体抑制剂抑制 TGFβ 通路也抑制了 RPE 细胞中的生存素表达。我们的研究表明,生存素通过与 RPE 细胞中的 TGFβ 通路相互作用促进 EMT。使用小分子抑制剂靶向生存素可能为治疗 PVR 疾病提供一种新方法。