Abstract
Research has revealed that microRNA (miR)‑4500 is downregulated in non‑small cell lung cancer (NSCLC), and miR‑4500 suppresses tumor growth by targeting lin‑28 homolog B and NRAS proto‑oncogene, GTPase. In the present study, it was reported that signal transducer and activator of transcription 3 (STAT3) may function as a novel target gene for miR‑4500 in NSCLC. The experiments conducted in the present study confirmed that the miR‑4500 expression was decreased in NSCLC tissues and cells compared with adjacent normal tissues and a normal lung cell line. miR‑4500 suppressed the cell proliferation, migration, invasion and promoted apoptosis of the human NSCLC cell lines A549 and H1975. Expression of STAT3 was negatively correlated with miR‑4500 expression in vivo. A luciferase reporter assay suggested that miR‑4500 directly targeted the 3' untranslated region of STAT3. The tumor inhibition effect of small interfering RNA STAT3 in A549 and H1975 lines may be partially impaired by a miR‑4500 inhibitor. The results of the present study suggests that miR‑4500 may be a tumor suppressor and a potential therapeutic target in NSCLC.