Finally, the BC cells were used to establish xenograft tumor bearing mice models, and the results showed that knock-down of LncRNA SNHG15 inhibited tumor growth (Fig. 6a, b) and Ki67 expressions (Fig. 6c) in mice tumor tissues to hinder tumorigenesis of BC cells in vivo, which were all reversed by both silencing miR-451 and upregulating c-Myc (Fig. 6a, c). This evidence concerns the gene MKI67 and neoplasm.