The growth of glioma tumor was significantly suppressed in anti-miR-21 or sh-CXCR4 treatment alone groups compared to negative control, while the anti-miR-21 + sh-CXCR4 treatment obviously reduced the tumor growth compared to the anti-miR-21 or sh-CXCR4 group (Figures 5(b) and 5(c)). Here, CXCR4 is linked to central nervous system cancer.