Long non-coding RNA PVT1 contributes to cell growth and metastasis in non-small-cell lung cancer by regulating miR-361-3p/SOX9 axis and activating Wnt/β-catenin signaling pathway

Abstract

Lung cancer is the most frequent cause of cancer-related mortality in men, and 85 % of lung cancer is diagnosed as non-small-cell lung cancer (NSCLC). Plasmacytoma variant translocation1 (PVT1) serves as an oncogenic factor in NSCLC. However, the pathogenesis of PVT1 in NSCLC is still vague. The expression levels of PVT1, sex determining region Y (SRY)-related high mobility group (HMG)-box9 (SOX9), and microRNA (miR)-361-3p in NSCLC tissues and cells were detected by quantitative real-time polymerase chain reaction (RT-qPCR). The protein levels of SOX9, β-catenin, and c-Myc were detected by western blot assay. Cell proliferation, apoptosis, migration and invasion were measured by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT), flow cytometry, transwell assays, severally. The interaction between miR-361-3p and PVT1 or SOX9was predicted by starBase, and then verified by the dual-luciferase reporter and RNA Immunoprecipitation (RIP) assays. PVT1 and SOX9 was highly expressed in NSCLC tumor tissues and cells. PVT1 facilitated proliferation, migration, invasion and hindered apoptosis of NSCLC cells. MiR-361-3p was a target of PVT1 in NSCLC cells. SOX9 acted as a target of miR-361-3p. PVT1 worked as a miR-361-3p sponge to regulate SOX9 expression. PVT1 modulate the Wnt/β-catenin Signaling Pathway by miR-361-3p/SOX9 axis. Our studies disclosed that PVT1 boosted proliferation, migration, invasion and curbed apoptosis by miR-361-3p/SOX9 axis, providing the possible therapeutic strategy for NSCLC.

Keywords: Non-small-cell lung cancer; PVT1; SOX9; Wnt/β-catenin signaling pathway; miR-361-3p.