Down-regulation of miR-500 and miR-628 suppress non-small cell lung cancer proliferation, migration and invasion by targeting ING1

Background: MicroRNAs (miRNAs) have been consistently demonstrated to be involved in non-small cell lung cancer (NSCLC) as either tumor oncogenes or tumor suppressors. However, the detailed role of miR-500 and miR-628 in NSCLC remain poorly understood.

Methods: The expressions of miR-500 and miR-628 in NSCLC tissues and cell lines were measured by quantitative real-time PCR (qRT-PCR). Cells migration, invasion, proliferation, adhesion and apoptosis abilities were test to analyze the biological functions of miR-500 and miR-628 in NSCLC. A bioinformatic analysis was conducted to predict the target genes regulated by miR-500 and miR-628 using TargetScan (http://www.targetscan.org/mamm/). Luciferase reporter assay was employed to validate the direct targeting of ING1 by miR-500 and miR-628.

Results: In this study, miR-500 and miR-628 were up-regulated with NSCLC tissues. Furthermore, inhibition of miR-500 and miR-628 significantly suppressed NSCLC cells proliferation, migration, invasion and adhesion, and induced NSCLC cells apoptosis. Additionally, the result showed that ING1 functioned as the direct target for miR-500 and miR-628, which was a core tumor suppressor in regulating NSCLC progression. Over-expression of ING1 could dramatically inhibit NSCLC cells proliferation, migration and invasion, and promote cells apoptosis.

Conclusion: These results brought new insights into the oncogenic role of miR-500 and miR-628 in NSCLC, indicating that miR-500 and miR-628 might be the novel biomarkers for the diagnosis and prognosis of NSCLC.