Long Noncoding RNA LINC00460 Modulates MMP-9 to Promote Cell Proliferation, Invasion and Apoptosis by Targeting miR-539 in Papillary Thyroid Cancer

Background: Increasing evidence shows that Long non-coding RNAs (lncRNAs) involve in the development and progression processes of various cancers, including papillary thyroid cancer (PTC). In this study, we focused on the regulation function of lncRNA LINC00460 in the development of PTC. Methods: Expression of LINC00460 was detected using quantitative real-time PCR (qRT-PCR) and Western blot assay. Cell proliferation, cell apoptosis and cell invasion were determined through CCK-8 assay, flow cytometry, and Transwell assay, respectively. In addition, target sites were detected by the dual-luciferase reporter gene assay. Results: LINC00460 expression was markedly up-regulated in PTC tissues and cells compared to their corresponding controls by quantitative real-time PCR (qRT-PCR). Meanwhile, LINC00460 knockdown notably inhibited the proliferation capacity, accelerated the apoptosis and down-regulated the invasion-related proteins (MMP-2, MMP-9, ZEB1) expression. In addition, bioinformatics tools predicted that miR-539 both targeted with the 3'-UTR of LINC00460 and MMP-9, which was confirmed by luciferase reporter assay and Western blot. Conclusion: These findings indicated that LINC00460 can modulate MMP-9 expression to promote cell proliferation, invasion and apoptosis through targeting miR-539, suggesting act as an oncogenic RNA in PTC and provide a new therapeutic perspective.