Department of Cardiovascular Surgery, Changhai Hospital, Second Military Medical University, Shanghai, China.
Department of Cardiovascular Surgery, Changhai Hospital, Second Military Medical University, Shanghai, China.
J Thorac Cardiovasc Surg. 2017 Nov;154(5):1511-1521.e6. doi: 10.1016/j.jtcvs.2017.05.066. Epub 2017 May 25.
To investigate the expression of Nanog homeobox (NANOG) in thoracic aortic dissection (TAD) and the role of NANOG in regulating human aortic vascular smooth muscle cells (VSMCs) phenotype switch.
Aortic specimens were collected from 20 patients undergoing TAD and 10 controls. VSMCs were isolated by adherent cultivation approach. The expression of NANOG, osteopontin (OPN), and VSMCs phenotype markers were determined by quantitative real-time polymerase chain reaction, Western blot, immunohistochemistry, and immunofluorescence. Cell counting, scratch wound-healing assay, Transwell migration, and apoptosis assays were used for cell function assessment. Deoxyribonucleic acid-protein binding detection was performed by chromatin immunoprecipitation.
Our experiment results showed that NANOG and OPN were highly expressed in TAD aortic wall and VSMCs, both accompanying VSMCs phenotype switch. Overexpression of NANOG induced the up-regulation of VSMCs synthetic marker matrix metalloproteinase 2 and the down-regulation of VSMCs contractile markers α-smooth muscle actin and smooth muscle 22α. Overexpression of NANOG also enhanced the proliferation, migration, and antiapoptosis capabilities of VSMCs. The results also showed that these functions of NANOG was via OPN and NANOG directly up-regulated OPN by binding to its promoter region.
Our study suggests that NANOG is highly expressed in TAD aortic wall and VSMCs. Increased NANOG promotes VSMCs phenotype switch by directly up-regulating OPN through binding to its promoter region.
研究 Nanog 同源盒（NANOG）在胸主动脉夹层（TAD）中的表达及其在调节人主动脉血管平滑肌细胞（VSMCs）表型转换中的作用。
收集 20 例 TAD 患者和 10 例对照患者的主动脉标本。采用贴壁培养法分离 VSMCs。采用实时定量聚合酶链反应、Western blot、免疫组织化学和免疫荧光法检测 NANOG、骨桥蛋白（OPN）和 VSMCs 表型标志物的表达。细胞计数、划痕愈合试验、Transwell 迁移和凋亡试验用于细胞功能评估。采用染色质免疫沉淀法进行脱氧核糖核酸-蛋白质结合检测。
我们的实验结果表明，NANOG 和 OPN 在 TAD 主动脉壁和 VSMCs 中均高度表达，同时伴随着 VSMCs 表型转换。NANOG 的过表达诱导 VSMCs 合成标志物基质金属蛋白酶 2 的上调和 VSMCs 收缩标志物α-平滑肌肌动蛋白和平滑肌 22α 的下调。NANOG 的过表达还增强了 VSMCs 的增殖、迁移和抗凋亡能力。结果还表明，NANOG 通过与 OPN 启动子区域结合直接上调 OPN，从而发挥这些功能。
本研究表明，NANOG 在 TAD 主动脉壁和 VSMCs 中高度表达。增加的 NANOG 通过与 OPN 启动子区域结合直接上调 OPN，从而促进 VSMCs 表型转换。
