Abstract: Objective To explore the expression and function of hsa-miR-4483 in breast cancer cells. Methods Using TargetScan to find out how can-miR-4483 act on the c-Myc gene, and RT-qPCR verified the expression of hsa-miR-4483. Transfected MCF-7 and MDA-MB-231 and set up NC-negative controls, Western blot was used to detect the expression of the hsa-miR-4483 gene, MTT assay and Transwell chamber experiment were applied to verify the proliferation and migration of breast cancer cells. Results The expression of hsa-miR-4483 was significantly lower (P＜0.001, P＜0.01) in MCF-7 and MDA-MB-231(P＜0.001, P＜0.01) The up-regulation of c-myc in MCF-7 and MDA-MB-231 promoted cell proliferation and migration (P＜0.001). Conclusions hsa-miR-4483 can promote the proliferation and migration of breast cancer cell lines, which plays a regulatory role in the development of breast cancer and its prognosis.

Key words: microRNA, breast cancer, proliferation, migration, proliferation curve