We aimed to explore the biological activity of lncRNA SPRY4-IT1 in breast cancer cells and whether N-terminal polypeptide derived from viral macrophage inflammatory protein II (NT21MP) could exert its anti-tumor effect by regulating lncRNA SPRY4-IT1 and its target gene SKA2. Real-time RT-PCR, Western blotting, wound healing, and invasion assays were used to achieve this goal. This evidence concerns the gene SPRY4 and breast cancer.