MiR-421 Is Overexpressed and Promotes Cell Proliferation in Non-Small Cell Lung Cancer.

BACKGROUND

Lung cancer is the main cause of cancer--related deaths worldwide, and the overall 5-year survival rate of non-small cell lung cancer (NSCLC) remained low. -MicroRNAs had been confirmed to be an important regulator in tumor progression, and they could serve as either tumor promoters or suppressors in NSCLC.

OBJECTIVES

To identify the novel cancer-specific biomarkers for NSCLC patients, which may be useful to monitor tumor progression and improve NSCLC patients' survival.

METHOD

The expression profile of miR-421 was analyzed in NSCLC samples using public datasets, including The Cancer Genome Atlas and GSE102286. The expression level of miR-421 was detected by reverse transcription-polymerase chain reaction. Cell proliferation and cell cycle were detected by Cell Counting Kit assay, flow cytometry assay, respectively. Kyoto Encyclopedia of Genes and Genomes analysis were applied to determine the biological roles of miR-421, based on the online DAVID system. Statistical comparisons between groups of normalized data were performed using t test or Mann-Whitney U test according to the test condition.

RESULTS

In this study, we focused on exploring the roles of miR-421 in NSCLC prognosis and growth. The present study for the first time showed that miR-421 was overexpressed in NSCLC and associated with a shorter overall survival time of patients with NSCLC. Bioinformatics analysis revealed miR-421 was involved in transcription, cell cycle, and insulin signaling pathway regulation. Furthermore, a gain of function assay showed that overexpression of miR-421 could promote NSCLC cell proliferation and cell cycle progression.

CONCLUSIONS

Our findings suggest that miR-421 might be a promising prognostic and therapeutic target for NSCLC.