ABSTRACT
@#[Abstract] Objective: To investigate the molecular mechanism of microRNA-101 (miR-101) inhibiting the migration and invasion of non-small cell lung cancer (NSCLC) via targeting fibroblast growth factor 2 (FGF2). Methods: qPCR was used to detect the expression levels of miR-101 and FGF2 in human normal lung epithelial BEAS-2B cells and NSCLC cell lines (A549, H661 and SK-MES-1) as well as A549 cells after transfection. MiR-NC, miR-101 mimics, miR-IN-NC, miR-101 inhibitor or pcDNA-3.1 empty plasmid, pcDNA-FGF2 were respectively transfected into A549 cells. Wound healing assay and Transwell assay were used to examine the effects of overexpression of miR-101 and FGF2 on the migration and invasion of A549 cells. Western blotting(WB) was used to detect the expression levels of FGF2, E-cadherin, N-cadherin, Vimentin, ERK1/2 and p-ERK1/2 in A549 cells in each group. Results: The expression level of miR-101 in NSCLC cell lines were significantly lower than that in normal lung epithelial cells (all P<0.05), while the expression level in A549 cells was the lowest. Overexpression of miR-101 significantly inhibited the migration (P<0.05) and invasion (P<0.01) of A549 cells, increased the expression level of E-cadherin but decreased the expression level of Vimentin (P<0.05),N-cadherin (P<0.01) and p-ERK1/2 (P<0.05). Inhibition of miR-101 significantly enhanced the invasion and migration of A549 cells (all P<0.05), decreased the expression level of E-cadherin but increased the expression levels of Vimentin, N-cadherin and p-ERK1/2 (all P<0.05). The results of WB and Dual-luciferase reporter gene assay verified that FGF2 is a direct target gene of miR-101, and over‐expression of FGF2 significantly enhanced the invasion and migration of A549 cells (all P<0.01), decreased the expression of E-cadherin (P<0.01) but increased the expressions of Vimentin (P<0.01), N-cadherin (P<0.05) and p-ERK1/2 (P<0.01). Compared with the FGF2 overexpression alone group, co-overexpression of miR-101 and FGF2 significantly reduced the invasion and migration of A549 cells (all P<0.01), increased the expression of E-cadherin (P<0.01), and decreased the expressions of Vimentin (P<0.01), N-cadherin (P<0.05) and p-ERK1/2 (P<0.01). Conclusion: By targeting FGF2, miR-101 inhibits the invasion and migration of NSCLC cells through suppressing the epithelial-mesenchymal transition (EMT) and ERK signaling pathway.