Gene expression analyses in inner meniscus cells after overexpression of miR-210. (A) Real-time PCR analysis of collagen type 1 alpha 1 (Col1a1), collagen type 2 alpha 1 (Col2a1), vascular endothelial growth factor (VEGF) and fibroblast growth factor-2 (FGF2) at 7 days after in vitro transfection of inner meniscus cells. Expression of only Col2a1 was significantly higher than that in the control group (*P < 0.05, N.S. (no significant difference), n = 6 for each group). (B) Immunohistochemical analysis indicates that collagen type 2 was highly expressed in the miR-210 group (bar = 100 μm). These results demonstrate that miR-210 could enhance the expression of collagen type 2 in the meniscus cells. ds, double stranded.