LncRNA WTAPP1 Promotes Migration and Angiogenesis of Endothelial Progenitor Cells via MMP1 Through MicroRNA 3120 and Akt/PI3K/Autophagy Pathways.

Efficient recruitment and angiogenesis of endothelial progenitor cells (EPCs) are critical during a thrombus event. However, the details of EPC recruitment and the regulation of angiogenesis have not been fully determined. The aim of this study was to determine the role of the long noncoding (lnc)RNA Wilms tumor 1 associated protein pseudogene 1 (WTAPP1) in regulation of the migration and angiogenesis of EPCs. EPCs were isolated from human peripheral blood and characterized by flow cytometry, after which lentivirus-mediated lncRNA WTAPP1 overexpression and knockdown were performed. Scratch assay, Transwell assay, and in vitro and in vivo tube formation assays were performed to measure cell migration, invasion, and angiogenic abilities, respectively. Moreover, a microarray screen, bioinformatic prediction, and quantitative PCR and Western blot of miRNAs interacting with lncRNA WTAPP1 were conducted. Western blot was carried out to elucidate the relationship among WTAPP1, miR-3120-5P, and MMP-1 in the autophagy pathway. WTAPP1 positively regulated migration, invasion, and in vitro and in vivo tube formation in EPCs by increasing MMP-1 expression and activating PI3K/Akt/mTOR signaling. Furthermore, WTAPP1 contains a putative miR-3120-5P binding site. Suppression of WTAPP1 by miR-3120-5P decreased the level of MMP-1. In addition, we demonstrated that suppression of the autophagy pathway is involved in the effects of WTAPP1 on EPC migration and angiogenesis. The lncRNA WTAPP1, a molecular decoy for miR-3120-5p, regulates MMP-1 expression via the PI3K/Akt and autophagy pathways, thereby mediating cell migration and angiogenesis in EPCs. Acting as a potential therapeutic target, the lncRNA WTAPP1 may play an important role in the pathogenesis of DVT. Stem Cells 2018;36:1863-12.