The Novel miRNA N-72 Regulates EGF-Induced Migration of Human Amnion Mesenchymal Stem Cells by Targeting MMP2

Human amnion mesenchymal stem cells (hAMSCs) are promising sources of stem cells in regenerative medicine. The migration stimulated by cytokines is critical for mesenchymal stem cells (MSCs)-based cytotherapy, while the regulatory mechanisms of EGF (epidermal growth factor)-induced hAMSC migration are largely unclear. Here, a novel miRNA N-72 (GenBank accession number: MH269369) has been discovered, and its function on EGF-induced migration in hAMSCs was investigated. High-purity hAMSCs were isolated and cultured in vitro, which were characterized by flow cytometry and trilineage differentiation. The N-72 located on chromosome three was conserved, and pri-N-72 owned the ability to form a stem-loop secondary structure, which was predicated by bioinformatic programs. The expression of mature N-72 was verified in several human cells including hAMSC by real-time PCR. In EGF-stimulated hAMSC, N-72 showed a significant reduction in a PI3K and p38 MAPK-dependent manner, and N-72 mimics transfection-inhibited EGF-induced migration, which was verified by scratch assay and transwell assay. Further, the predicated target gene MMP2 was proved to be a direct target of N-72 via luciferase reporter assay, real-time PCR, and Western blotting. The results that MMP2 silencing repressed hAMSC migration suggested MMP2 as a functional downstream target of N-72. In summary, we have discovered the novel N-72, and it was crucial for EGF-induced migration by targeting MMP2 in hAMSCs.