miR-219a-5p represses migration and invasion of osteosarcoma cells via targeting EYA2.

EYA2 is the developmental transcription factor and phosphatase, playing an important role in numerous species in regulating cell death and differentiation. Recent studies showed that EYA2 is dysregulated and involved in the progression of various cancers. However, the expression and role of EYA2 in osteosarcoma remains unclear. Here, we found that EYA2 expression was evidently upregulated osteosarcoma (OS) tissue and cell lines. Next, we predicted EYA2-targeting miRNAs, which was further evaluated using a dual luciferase reporter assay. We found that miR-219a-5p significantly repressed EYA2 expression via binding to the 3'-UTR of EYA2. Furthermore, overexpressed miR-219a-5p significantly repressed OS cell invasion and migration, which was reversed by overexpressed EYA2. While silenced miR-219a-5p induced OS cell invasion and migration, which was reversed by silenced EYA2. In conclusion, our study revealed that miR-219a-5p function as tumour suppressor regulates OS cell invasiveness by repressing EYA2 expression.