Department of Pulmonary and Critical Care Medicine, Hunan Provincial People's Hospital, The First Affiliated Hospital of Hunan Normal University, Changsha, 410005, Hunan, PR China.
Department of Traditional Chinese Medicine, Hunan Provincial People's Hospital, The First Affiliated Hospital of Hunan Normal University, Changsha, 410005, Hunan, PR China.
Lab Invest. 2021 Feb;101(2):142-154. doi: 10.1038/s41374-020-00487-0. Epub 2020 Sep 28.
Epithelial-to-mesenchymal transition (EMT) of epithelium and airway epithelial cell proliferation disorder are key events in idiopathic pulmonary fibrosis (IPF) pathogenesis. During EMT, epithelial cell adhesion molecules (EpCAM, such as E-cadherin) are downregulated, cytokeratin cytoskeletal transforms into vimentin-based cytoskeleton, and the epithelial cells acquire mesenchymal morphology. In the present study, we show abnormal upregulation of tumor protein p63 (TP63) and downregulation of miR-184 in IPF. Transforming growth factor beta 1 (TGF-β1) stimulation of BEAS-2B and A549 cell lines significantly increased the protein levels of Tp63, alpha-smooth muscle actin (α-SMA), and vimentin, but decreased EpCAM protein levels, and promoted viability of both BEAS-2B and A549 cell lines. TP63 knockdown in BEAS-2B and A549 cell lines significantly attenuated above-described TGF-β1-induced fibrotic changes. miR-184 targeted TP63 3'-UTR to inhibit Tp63 expression. miR-184 overexpression within BEAS-2B and A549 cell lines also attenuated TGF-β1-induced fibrotic changes. miR-184 overexpression attenuated bleomycin-induced pulmonary fibrosis in mice. Moreover, TP63 overexpression aggravated TGF-β1-stimulated fibrotic alterations within BEAS-2B and A549 cells and significantly reversed the effects of miR-184 overexpression, indicating miR-184 relieves TGF-β1-stimulated fibrotic alterations within BEAS-2B and A549 cells by targeting TP63, while TP63 overexpression reversed miR-184 cellular functions. In conclusion, the miR-184/TP63 axis modulates the TGF-β1-induced fibrotic alterations in epithelial cell lines and bleomycin-induced pulmonary fibrosis in mice. Therefore, these results confirm that the miR-184/TP63 axis is involved in IPF progression.
上皮-间充质转化（EMT）和气道上皮细胞增殖紊乱是特发性肺纤维化（IPF）发病机制中的关键事件。在 EMT 过程中，上皮细胞黏附分子（EpCAM，如 E-钙黏蛋白）下调，细胞角蛋白细胞骨架转化为基于波形蛋白的细胞骨架，上皮细胞获得间充质形态。在本研究中，我们显示在 IPF 中肿瘤蛋白 p63（TP63）异常上调和 miR-184 下调。转化生长因子β1（TGF-β1）刺激 BEAS-2B 和 A549 细胞系显著增加了 Tp63、α-平滑肌肌动蛋白（α-SMA）和波形蛋白的蛋白水平，但降低了 EpCAM 蛋白水平，并促进了 BEAS-2B 和 A549 细胞系的活力。在 BEAS-2B 和 A549 细胞系中敲低 TP63 显著减弱了上述 TGF-β1 诱导的纤维化变化。miR-184 靶向 TP63 3'-UTR 抑制 Tp63 表达。miR-184 在 BEAS-2B 和 A549 细胞系中的过表达也减弱了 TGF-β1 诱导的纤维化变化。miR-184 过表达减轻了博来霉素诱导的小鼠肺纤维化。此外，TP63 过表达加重了 TGF-β1 刺激的 BEAS-2B 和 A549 细胞中的纤维化改变，并显著逆转了 miR-184 过表达的作用，表明 miR-184 通过靶向 TP63 缓解了 BEAS-2B 和 A549 细胞中 TGF-β1 刺激的纤维化改变，而 TP63 过表达逆转了 miR-184 的细胞功能。总之，miR-184/TP63 轴调节上皮细胞系中的 TGF-β1 诱导的纤维化改变和博来霉素诱导的小鼠肺纤维化。因此，这些结果证实 miR-184/TP63 轴参与了 IPF 的进展。
