PDF(Pubmed)
Abstract：
BACKGROUND: Radiation-induced pulmonary fibrosis (RIPF) is a chronic, progressive, irreversible lung interstitial disease that develops after radiotherapy. Although several previous studies have focused on the mechanism of epithelial-mesenchymal transition (EMT) in lung epithelial cells, the essential factors involved in this process remain poorly understood. The DNA-dependent protein kinase catalytic subunit (DNA-PKcs) exhibits strong repair capacity when cells undergo radiation-induced damage; whether DNA-PKcs regulates EMT during RIPF remains unclear.
OBJECTIVE: To investigate the role and molecular mechanism of DNA-PKcs in RIPF and provide an important theoretical basis for utilising DNA-PKcs-targeted drugs for preventing RIPF.
METHODS: DNA-PKcs knockout (DPK-/-) mice were generated via the Cas9/sgRNA technique and subjected to whole chest ionizing radiation (IR) at a 20 Gy dose. Before whole chest IR, the mice were intragastrically administered the DNA-PKcs-targeted drug VND3207. Lung tissues were collected at 1 and 5 months after IR.
RESULTS: The expression of DNA-PKcs is low in pulmonary fibrosis (PF) patients. DNA-PKcs deficiency significantly exacerbated RIPF by promoting EMT in lung epithelial cells. Mechanistically, DNA-PKcs deletion by shRNA or inhibitor NU7441 maintained the protein stability of Twist1. Furthermore, AKT1 mediated the interaction between DNA-PKcs and Twist1. High Twist1 expression and EMT-associated changes caused by DNA-PKcs deletion were blocked by insulin-like growth factor-1 (IGF-1), an AKT1 agonist. The radioprotective drug VND3207 prevented IR-induced EMT and alleviated RIPF in mice by stimulating the kinase activity of DNA-PKcs.
CONCLUSIONS: Our study clarified the critical role and mechanism of DNA-PKcs in RIPF and showed that it could be a potential target for preventing RIPF.
OBJECTIVE: To investigate the role and molecular mechanism of DNA-PKcs in RIPF and provide an important theoretical basis for utilising DNA-PKcs-targeted drugs for preventing RIPF.
METHODS: DNA-PKcs knockout (DPK-/-) mice were generated via the Cas9/sgRNA technique and subjected to whole chest ionizing radiation (IR) at a 20 Gy dose. Before whole chest IR, the mice were intragastrically administered the DNA-PKcs-targeted drug VND3207. Lung tissues were collected at 1 and 5 months after IR.
RESULTS: The expression of DNA-PKcs is low in pulmonary fibrosis (PF) patients. DNA-PKcs deficiency significantly exacerbated RIPF by promoting EMT in lung epithelial cells. Mechanistically, DNA-PKcs deletion by shRNA or inhibitor NU7441 maintained the protein stability of Twist1. Furthermore, AKT1 mediated the interaction between DNA-PKcs and Twist1. High Twist1 expression and EMT-associated changes caused by DNA-PKcs deletion were blocked by insulin-like growth factor-1 (IGF-1), an AKT1 agonist. The radioprotective drug VND3207 prevented IR-induced EMT and alleviated RIPF in mice by stimulating the kinase activity of DNA-PKcs.
CONCLUSIONS: Our study clarified the critical role and mechanism of DNA-PKcs in RIPF and showed that it could be a potential target for preventing RIPF.
摘要：
背景：放射性肺纤维化（RIPF）是一种慢性，进步,放疗后发展的不可逆的肺间质疾病。尽管先前的一些研究集中在肺上皮细胞中上皮-间质转化（EMT）的机制上，参与这一过程的基本因素仍然知之甚少。当细胞遭受辐射诱导的损伤时，DNA依赖性蛋白激酶催化亚基（DNA-PKcs）表现出很强的修复能力；DNA-PKcs在RIPF期间是否调节EMT尚不清楚。
目的：探讨DNA-PKcs在RIPF中的作用及分子机制，为利用DNA-PKcs靶向药物预防RIPF提供重要的理论依据。
方法：通过Cas9/sgRNA技术产生DNA-PKcs敲除（DPK-/-）小鼠，并以20Gy剂量进行全胸部电离辐射（IR）。在整个胸部IR之前，小鼠胃内给药DNA-PKcs靶向药物VND3207.在IR后1和5个月收集肺组织。
结果：肺纤维化（PF）患者中DNA-PKcs的表达较低。DNA-PKcs缺乏通过促进肺上皮细胞的EMT而显著加剧RIPF。机械上,shRNA或抑制剂NU7441的DNA-PKcs缺失维持了Twist1的蛋白质稳定性。此外，AKT1介导DNA-PKcs与Twist1的相互作用。胰岛素样生长因子-1（IGF-1）阻断了DNA-PKcs缺失引起的Twist1高表达和EMT相关变化，AKT1激动剂。辐射防护药物VND3207通过刺激DNA-PKcs的激酶活性来预防IR诱导的EMT并减轻小鼠的RIPF。
结论：我们的研究阐明了DNA-PKcs在RIPF中的关键作用和机制，并表明它可能是预防RIPF的潜在靶标。
目的：探讨DNA-PKcs在RIPF中的作用及分子机制，为利用DNA-PKcs靶向药物预防RIPF提供重要的理论依据。
方法：通过Cas9/sgRNA技术产生DNA-PKcs敲除（DPK-/-）小鼠，并以20Gy剂量进行全胸部电离辐射（IR）。在整个胸部IR之前，小鼠胃内给药DNA-PKcs靶向药物VND3207.在IR后1和5个月收集肺组织。
结果：肺纤维化（PF）患者中DNA-PKcs的表达较低。DNA-PKcs缺乏通过促进肺上皮细胞的EMT而显著加剧RIPF。机械上,shRNA或抑制剂NU7441的DNA-PKcs缺失维持了Twist1的蛋白质稳定性。此外，AKT1介导DNA-PKcs与Twist1的相互作用。胰岛素样生长因子-1（IGF-1）阻断了DNA-PKcs缺失引起的Twist1高表达和EMT相关变化，AKT1激动剂。辐射防护药物VND3207通过刺激DNA-PKcs的激酶活性来预防IR诱导的EMT并减轻小鼠的RIPF。
结论：我们的研究阐明了DNA-PKcs在RIPF中的关键作用和机制，并表明它可能是预防RIPF的潜在靶标。
