MiR‐372‐3p promotes cell growth and metastasis by targeting FGF 9 in lung squamous cell carcinoma

The aim of this study was to study the role of miR‐372‐3p in lung squamous cell carcinoma ( LSCC ) cell proliferation and invasion by suppressing FGF 9 . RT ‐ PCR was used to determine miR‐372‐3p and FGF 9 mRNA expression in tissues and cells. Western blot was used to determine FGF 9 expression in tissues and NCI ‐H520 cell line. Dual luciferase reporter gene assay was conducted to confirm that FGF 9 can be directly targeted by miR‐372‐3p. MTT , colony formation assays were conducted to investigate the effects of ectopic miR‐372‐3p and FGF 9 expression on NCI ‐H520 cell growth. Flow cytometry was used to analyze the influence of miR‐372‐3p and FGF 9 expression on cell cycle distribution and apoptosis. Transwell assay was also conducted to see the effects of miR‐372‐3p and FGF 9 expression on NCI ‐H520 cell invasiveness. MiR‐372‐3p was found significantly overexpressed in both LSCC tissues and cell lines, whereas FGF 9 mRNA was found underexpressed in LSCC tissues. MiR‐372‐3p directly bound to wild‐type FGF 9 mRNA 3′ UTR , therefore led to the reduction in FGF 9 expression. The upregulation of FGF 9 or the downregulation of miR‐372‐3p substantially retarded LSCC cell growth, mitosis, and invasion. MiR‐372‐3p enhanced LSCC cell proliferation and invasion through inhibiting FGF9 .