| First Author | Qian G | Year | 2022 |
| Journal | Am J Respir Cell Mol Biol | Volume | 66 |
| Issue | 2 | Pages | 171-182 |
| PubMed ID | 34710342 | Mgi Jnum | J:368125 |
| Mgi Id | MGI:8213745 | Doi | 10.1165/rcmb.2021-0175OC |
| Citation | Qian G, et al. (2022) DOCK2 Promotes Pleural Fibrosis by Modulating Mesothelial to Mesenchymal Transition. Am J Respir Cell Mol Biol 66(2):171-182 |
| abstractText | Mesothelial to mesenchymal transition (MesoMT) is one of the crucial mechanisms underlying pleural fibrosis, which results in restrictive lung disease. DOCK2 (dedicator of cytokinesis 2) plays important roles in immune functions; however, its role in pleural fibrosis, particularly MesoMT, remains unknown. We found that amounts of DOCK2 and the MesoMT marker alpha-SMA (alpha-smooth muscle actin) were significantly elevated and colocalized in the thickened pleura of patients with nonspecific pleuritis, suggesting the involvement of DOCK2 in the pathogenesis of MesoMT and pleural fibrosis. Likewise, data from three different pleural fibrosis models (TGF-beta [transforming growth factor-beta], carbon black/bleomycin, and streptococcal empyema) consistently demonstrated DOCK2 upregulation and its colocalization with alpha-SMA in the pleura. In addition, induced DOCK2 colocalized with the mesothelial marker calretinin, implicating DOCK2 in the regulation of MesoMT. Our in vivo data also showed that DOCK2-knockout mice were protected from Streptococcus pneumoniae-induced pleural fibrosis, impaired lung compliance, and collagen deposition. To determine the involvement of DOCK2 in MesoMT, we treated primary human pleural mesothelial cells with the potent MesoMT inducer TGF-beta. TGF-beta significantly induced DOCK2 expression in a time-dependent manner, together with alpha-SMA, collagen 1, and fibronectin. Furthermore, DOCK2 knockdown significantly attenuated TGF-beta-induced alpha-SMA, collagen 1, and fibronectin expression, suggesting the importance of DOCK2 in TGF-beta-induced MesoMT. DOCK2 knockdown also inhibited TGF-beta-induced Snail upregulation, which may account for its role in regulating MesoMT. Taken together, the current study provides evidence that DOCK2 contributes to the pathogenesis of pleural fibrosis by mediating MesoMT and deposition of neomatrix and may represent a novel target for its prevention or treatment. |
