RESUMEN
Aim To investigate the involvement and mechanism of miR-619-5p in the proliferation, migration and invasion of human breast cancer cells. Methods The expression of miR-619-5p in breast cancer and normal breast tissue and cells was detected using bioinformatic analysis or qRT-PCR. After transfection with miR-619-5p mimics or inhibitors, the expression of miR-619-5p and EMT-related molecule mRNA was determined by qRT-PCR. Cell proliferation was detected using CCK-8 assay; cell migration and invasion capacity was estimated by the wound healing assay and Transwell assay. The protein levels of EMT-related molecules were analyzed by Western blot. The target genes of miR-619-5p were analyzed by bioinformatic a-nalysis, and a preliminary analysis of the potential target gene CREB1 was carried out. Results miR-619-5p was low expressed in breast cancer tissues and breast cancer cells. Compared with the control group, over-expression of miR-619-5p resulted in up-regula-tion of miR-619-5p expression levels and EMT epithelial markers, down-regulation of pro-EMT molecules and mesenchymal markers, impairment of cell proliferation, migration and invasion, and down-regulation of CREB1 expression. The results of the low miR-619-5p expression group were opposite to the above results. Conclusions In breast cancer tissue and cells, miR-619-5p expression is lower. miR-619-5p inhibits the proliferation, migration, invasion and EMT of breast cancer cells, and its possible mechanism of the effects may be targeting CREB1.