We believe that, just like the TLR9 signal pathways in other cancer cells, the activation of TLR9 may lead to enhanced invasiveness of U87 glioma cells, this was supported by our research, we found that the TLR9 agonist CpG ODN(ODN 2006) can significantly increased the invasiveness of U87 glioma cells(Fig. 4). Here, TLR9 is linked to central nervous system cancer.