SMO shRNA prevents osteosarcoma xenograft growth in vivo and prolongs survival. A, SMO shRNA or control shRNA transfected 143B cells (1 × 106) were inoculated subcutaneously. Established 143B tumors were measured. The tumor volume at day 7 was set at 1, and tumor volumes at subsequent time points were calculated. SMO shRNA inhibited tumor growth at 8 weeks compared to control shRNA. B, Kaplan-Meier survival curves from SMO shRNA groups and control shRNA. Kaplan-Meier analysis showed that SMO shRNA conferred a significant survival benefit (n = 6, p < 0.05). C, Immunohistochemical examination of ki67 was performed in xenograft tumors. SMO shRNA decreased SMO RNA in vivo. Ki67 staining revealed that proliferation of osteosarcoma cells was decreased by GSI treatment. The number of Ki67-positive cells was decreased to 30% of control revel by SMO shRNA (error bar means S.D.) (*: P < 0.01).