RESUMO
BACKGROUND: MicroRNA (miR)-214-3p is emerging as an important tumor suppressor in esophageal cancer. In this study, we examined the interaction between miR-214-3p and RAB14, a membrane trafficking protein shown to exert oncogenic functions in other malignancies, in esophageal cancer cells. METHODS: Studies were performed in a human esophageal epithelial cell line and a panel of esophageal cancer cell lines, as well in human specimens. MiR-214-3p expression was measured by digital PCR. Biotinylated RNA pull-down and luciferase reporter assays assessed binding. The xCELLigence RTCA system measured cell migration and invasion in real time. A lentiviral expression vector was used to create an esophageal cancer cell line stably expressing miR-214-3p. RESULTS: MiR-214-3p expression was decreased in esophageal cancer cell lines and human specimens compared to non-malignant controls. RAB14 mRNA stability and protein expression were decreased following miR-214-3p overexpression. Binding between miR-214-3p and RAB14 mRNA was observed. Either forced expression of miR-214-3p or RAB14 silencing led to a marked decrease in cellular migration and invasion. Esophageal cancer cells stably expressing miR-214-3p demonstrated decreased growth in a subcutaneous murine model. CONCLUSIONS: These results further support the tumor-suppressive role of miR-214-3p in esophageal cancer cells by demonstrating its ability to regulate RAB14 expression.
