HSP90 as a novel therapeutic target for posterior capsule opacification
HSP90 as a novel therapeutic target for posterior capsule opacification
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HSP90 作为后囊膜混浊的新型治疗靶点
DOI：
10.1016/j.exer.2019.107821
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发表时间：
2019-12-01
影响因子：
3.4
通讯作者：
Hu, Yanzhong
中科院分区：
文献类型：
--
作者：
Li, Jing;Xue, Wenxian;Hu, Yanzhong
后囊膜混浊（Posterior capsule opacification，PCO）是白内障手术后常见的并发症，由残留囊膜上皮细胞的增殖、迁移、上皮-间质转化（epithelial-mesenchymal transition，EMT）和肌成纤维细胞纤维化共同作用所致。已知HSP 90在病理生理条件下调节细胞的蛋白质稳态。然而，HSP 90在PCO形成中的作用尚不清楚。为此，我们采用体外培养的大鼠晶状体囊袋模型和透镜上皮细胞系，研究了HSP 90在PCO形成中的作用。采用免疫印迹和定量RT-PCR检测蛋白和mRNA的表达，TUNEL法检测细胞凋亡。通过细胞活力测定来测量细胞增殖。结果表明，17-AAG（Tanespimycin），一种HSP 90抑制剂，抑制永生化透镜上皮细胞系HLE-B3、SRA 01/04和mLEC的增殖，IC 50值分别为0.27、0.27和0.49 μ M。在离体培养的大鼠囊膜模型中，囊膜残余上皮细胞抵抗撕囊手术的应力，并且需要3-6天才能完全覆盖囊膜后壁。在此过程中，热休克因子1及其下游靶标HSP 90、HSP 25、α B-晶状体蛋白和HSP 40上调。用17-AAG处理抑制了囊残留上皮细胞的活力并诱导细胞凋亡，其特征在于ROS水平增加、凋亡DNA损伤以及半胱天冬酶9和3的活化。HSP 90参与调节EGF受体（EGFR）和TGF受体（TGFR）信号通路。发现HSP 90与EGFR相互作用，使得17-AAG对HSP 90的抑制使EGFR蛋白不稳定并抑制p-ERK 1/2和p-AKT水平。17-AAG还抑制TGF-β诱导的SMAD 2/3和ERK 1/2的磷酸化以及E-cadherin和ZO-1表达的降低。因此，这些数据表明，HSP 90的诱导保护被膜残余上皮细胞免受被膜破裂诱导的应激，并参与调节大鼠被膜残余上皮细胞的增殖、EMT和迁移的过程，至少部分地通过EGFR和TGFR信号通路。用17-AAG治疗抑制PCO形成，因此是用于PCO预防的潜在治疗候选物。
Posterior capsule opacification (PCO) is a common complication of cataract surgery, resulting from a combination of proliferation, migration, epithelial-mesenchymal transition (EMT) of residual capsular epithelial cells and fibrosis of myofibroblasts. HSP90 is known to regulate the proteostasis of cells under pathophysiological conditions. The role of HSP90 in PCO formation, however, is not clear. To do this, the lens epithelial cell lines and an ex vivo cultured rat capsular bag model were used to study the role of HSP90 in PCO formation. The expression of protein and mRNA was measured by immunoblotting and quantitative RT-PCR, and cell apoptosis was measured by TUNEL(TdT-mediated dUTP nick-end labeling). The cell proliferation was measured by cell viability assays. The results showed that 17-AAG (Tanespimycin), an inhibitor of HSP90, suppresses the proliferation of immortalized lens epithelial cell lines HLE-B3, SRA01/04, and mLEC, with IC50 values of 0.27, 0.27, and 0.49 mu M, respectively. In an ex vivo cultured rat capsular model, the capsular residual epithelial cells resisted the stress of the capsulorhexis surgery and took 3-6 days to completely overlay the capsular posterior wall. During this process, heat shock factor 1 and its downstream targets HSP90, HSP25, alpha B-crystallin, and HSP40 were upregulated. Treatment with 17-AAG inhibited the viability of capsular residual epithelial cells and induced the cells apoptosis, characterized by increases in ROS levels, apoptotic DNA injury, and the activation of caspases 9 and 3. HSP90 participated in regulating both EGF receptor (EGFR) and TGF receptor (TGFR) signaling pathways. HSP90 was found to interact with the EGFR, such that inhibition of HSP90 by 17-AAG destabilized the EGFR protein and suppressed p-ERK1/2 and p-AKT levels. 17-AAG also inhibited the TGF-beta-induced phosphorylation of SMAD2/3 and ERK1/2 and the decrease in E-cadherin and ZO-1 expression. Accordingly, these data suggest that the induction of HSP90 protects capsular residual epithelial cells against capsulorhexis-induced stress and participates in regulating the processes of proliferation, EMT and migration of rat capsular residual epithelial cells, at least partly, through the EGFR and TGFR signaling pathways. Treatment with 17-AAG suppresses PCO formation and is therefore a potential therapeutic candidate for PCO prevention.