Abstract
MicroRNA-198-5p (miR-198-5p) displays crucial roles in various cancers including non-small cell lung cancer (NSCLC), but the underlying molecular mechanisms remain unclear. Fucosyltransferase 8 (FUT8) is associated with tumour metastasis and prognosis. In this study, we explored the expression of miR-198-5p and FUT8 in NSCLC patients. Results showed that miR-198-5p was under-expressed in NSCLC tissues and was negatively correlated with tumour size, lymph node metastasis and tumour-node-metastasis stage, while FUT8 expression was highly upregulated. Next, we altered miR-198-5p expression using the mimic or inhibitor in the functional study. Results showed that miR-198-5p overexpression could inhibit the migration, invasion and epithelial-to-mesenchymal transition (EMT) of NSCLC cells; reversely, suppression of miR-198-5p enhanced cell migration, invasion and EMT. In vivo, miR-198-5p overexpression inhibited the formation of mouse lung and liver metastasis. Luciferase reporter, real-time PCR and western blot assays showed that miR-198-5p could directly target FUT8 and regulate FUT8 expression. Further, FUT8 overexpression reversed the effect of miR-198-5p overexpression on the migration, invasion and EMT of NSCLC cells. Taken together, miR-198-5p functions as a tumour suppressor by targeting FUT8 in NSCLC. MiR-198-5p may be developed as a new diagnostic biomarker and therapeutic target for lung cancer.