MiR-450a-5p promotes migration, invasion, and epithelial-mesenchymal transition in non-small cell lung cancer cells by targeting TCF21

Non-small cell lung cancer (NSCLC) poses a great threat to patients’ survival and is associated with a poor prognosis. Dysregulated microRNAs play critical roles in NSCLC progression, but the function of miR-450a-5p is largely unexplored. This study investigated the clinical significance, biological function, and underlying mechanism of miR-450a-5p in NSCLC cell migration and invasion. MiR-450a-5p expression was validated in 120 paired NSCLC tissues and adjacent normal tissues via RT-qPCR. Clinical correlation and survival analysis were performed. The functional role in migration, invasion, and epithelial-mesenchymal transition (EMT) was examined via Transwell assays and RT-qPCR after gain/loss of function experiments. Target genes of miR-450a-5p were predicted and verified by RNA pull-down, dual-luciferase reporter assay, and rescue assay. MiR-450a-5p exhibited notable upregulation in both NSCLC cell lines and clinical tissue samples. Its elevated expression showed a strong correlation with higher TNM stages, lymph node metastasis, and poorer overall survival. In vitro, miR-450a-5p overexpression promoted cell migration, invasion, and EMT (downregulating E-cadherin, upregulating N-cadherin, Vimentin, and Snail1), while its knockdown had opposite effects. The miR-450a-5p target identified was TCF21. Of note, TCF21 overexpression reversed miR-450a-5p-induced pro-metastatic and EMT changes. MiR-450a-5p appears to function as an oncogenic miRNA in NSCLC that contributes to migration, invasion, and EMT mainly via direct targeting of TCF21. The miR-450a-5p/TCF21 axis may serve as a potential prognostic correlate and therapeutic target.