miR-4284 Promotes Cell Proliferation, Migration, and Invasion in Non-Small Cell Lung Cancer Cells and is Associated with Postoperative Prognosis

PURPOSE: MicroRNA-4284 (miR-4284) was demonstrated to be aberrantly expressed and affected cell activities in some types of diseases, including cancer. However, the role of miR-4284 in non-small cell lung cancer (NSCLC) is largely unknown. The aim of this study was to investigate the expression and biological role of miR-4284 in NSCLC. PATIENTS AND METHODS: The qRT-PCR assay was applied to detect the expression of miR-4284 in NSCLC tissues and cell lines. Kaplan–Meier curve method and multiple Cox regression analyses were used to explore the prognostic factors for postoperative NSCLC patients. The CCK-8 assay was carried out to measure the proliferative abilities of A549 and H1299 cells. Transwell migration and invasion assays were used to determine the cell migratory and invasive capabilities of NSCLC cells. RESULTS: miR-4284 expression was upregulated in NSCLC tissues and cell lines. High expression of miR-4284 was correlated with poor differentiation, positive lymph node metastasis, and advanced TNM stages. In addition, postoperative patients with higher expression of miR-4284 exhibited a shorter overall survival time than those with lower expression of miR-4284. Moreover, the upregulation of miR-4284 accelerated cell proliferative, migratory, and invasive abilities of A549 and H1299 cells, while the downregulation of miR-4284 inhibited these cellular capabilities. CONCLUSION: miR-4284 was noticeably upregulated in NSCLC and associated with a poor prognosis of postoperative NSCLC patients. miR-4284 promoted the proliferation, migration, and invasion of A549 and H1299 cells. This study indicated that miR-4284 might serve as a prognostic biomarker and a potential therapeutic target for postoperative NSCLC patients.