miR-140 inhibited OS growth in vivo. (A) Mice were divided into two groups with five mice in each group. The graph represents tumor sizes at the indicated days, and the tumor growth curve indicated that miR-140 can inhibit the OS-engrafted tumorous growth relative to the scrambled group. (B, C) The transplants were resected and weighed after 28 days of the OS cell injection. (D) In the subcutaneously transplanted tumor, the miR-140 level of the miR-140 mimic group was overexpressed compared with that of the scramble group as detected by qPCR. (E) Immunohistochemistry analysis of HDAC4 in tumors from xenograft mice, and HDAC4 was decreased in the miR-140 group compared with scramble controls. *p < 0.05, **p < 0.01.