MicroRNA-30d-5p inhibits tumour cell proliferation and motility by directly targeting CCNE2 in non-small cell lung cancer

MicroRNAs (miRNAs) are small, single-stranded, non-coding RNA molecules that are dysregulated in many types of human cancers, although their precise functions in driving non-small cell lung cancer (NSCLC) are incompletely understood. In the present study, we found that miR-30d-5p, often downregulated in NSCLC tissues, significantly inhibited the growth, cell cycle distribution, and motility of NSCLC cells. Furthermore, we demonstrated that cyclin E2 (CCNE2), which was often upregulated in NSCLC tissues, was a direct target of miR-30d-5p. CCNE2 expression promoted the proliferation, invasion, and migration of NSCLC cells. In addition, the re-introduction of CCNE2 expression antagonised the inhibitory effects of miR-30d-5p on the capacity of NSCLC cells for proliferation and motility. Together, these results suggest that the miR-30d-5p/CCNE2 axis may contribute to NSCLC cell proliferation and motility, indicating miR-30d-5p as a potential therapeutic target for the treatment of NSCLC.