Down-regulating NEAT1 inhibited the viability and vasculogenic mimicry formation of sinonasal squamous cell carcinoma cells via miR-195-5p/VEGFA axis

The role of long non-coding RNA nuclear-enriched abundant transcript 1 (lncRNA NEAT1) in sinonasal squamous cell carcinoma (SNSCC) remained obscure. Target genes and potential binding sites of NEAT1, microRNA (miR)-195-5p and VEGFA were predicted using StarBase and TargetScan, and confirmed by dual-luciferase reporter assay. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to detect the expressions of NEAT1, vascular endothelial growth factor A (VEGFA) and miR-195-5p. Pearson's correlation analysis of NEAT1, miR-195-5p and VEGFA was conducted. Cell viability, apoptosis and tube formation capability were assessed by MTT assay, flow cytometry and capillary-like tube formation assay, respectively. Expressions of VEGFA and proteins related to the phosphatidylinositide 3-kinase/Protein Kinase B (PI3K/AKT) pathway were measured by Western blot. In SNSCC tissues and cells, the expressions of NEAT1 and VEGFA were up-regulated while the expression of miR-195-5p was down-regulated, and NEAT1 was negatively correlated with miR-195-5p yet positively correlated with VEGFA. Overexpressed VEGFA promoted the viability and capillary-like tube formation of SNSCC cells yet suppressed their apoptosis, while silencing VEGFA led to the opposite results. MiR-195-5p could bind to NEAT1, and down-regulating miR-195-5p reversed the effects of silencing NEAT1 on the expressions of NEAT1 and miR-195-5p, cell viability, apoptosis and capillary-like tube formation as well as PI3K/AKT pathway activation. VEGFA was the target of miR-195-5p, and overexpressed VEGFA reversed the effects of miR-195-5p. Down-regulating NEAT1 inhibited the viability and vasculogenic mimicry formation of SNSCC cells yet promoted their apoptosis via the miR-195-5p/VEGFA axis, providing a possible therapeutic target for SNSCC treatment.