Upregulated miR-1275 prevented BC development by modulating the direct expression of DVL3, PPP2R2D, TSHD4, CREB1, SYT7, and PRKACA. This is the first study revealing that miR-1275 function as a tumor-suppressive miRNA in BC cells, regulating numerous targets which were closely related with BC pathogenesis and oncogenesis. The gene discussed is SYT7; the disease is breast cancer.