Abstract
Non-small cell lung cancer (NSCLC) is a common malignant tumor with poor prognosis and an increasing number of cases. MicroRNA (miR)-4728 is related with the progression of various types of cancer, and is dysregulated in NSCLC, which indicates that miR-4728 may serve as a biomarker for NSCLC. The present study aimed to investigate the clinical significance of miR-4728 in NSCLC diagnosis and prognosis, and to explore the biological function of miR-4728 in NSCLC progression. Serum and tissue samples were collected from 122 patients with NSCLC. By conducting reverse transcription-quantitative PCR, the Cell Counting Kit-8 assay and Transwell assays, the expression of miR-4728 and its effect on NSCLC cell proliferation, migration and invasion were investigated. The diagnostic value of miR-4728 was evaluated by plotting a receiver operating characteristic curve, and Kaplan-Meier and Cox regression analyses were conducted to assess the prognostic value of miR-4728. miR-4728 was significantly downregulated in NSCLC serum and tissue samples compared with healthy controls, with a relatively high diagnostic accuracy and ability to predict poor overall survival time in patients with NSCLC. By conducting gain- and loss-of-function experiments, the results indicated that miR-4728 knockdown significantly promoted NSCLC cell proliferation, migration and invasion compared with the inhibitor negative control (NC) group. By contrast, miR-4728 overexpression displayed the opposite effect on NSCLC cell proliferation, migration and invasion. The present study indicated that miR-4728 was downregulated in NSCLC and may serve as a candidate diagnostic and prognostic biomarker. NSCLC cell proliferation, migration and invasion were inhibited by miR-4728 overexpression compared with the mimic NC group, which suggested that miR-4728 may serve as a therapeutic target for NSCLC.