The research results indicate that the TfR on the surface of CpG EXO/TGM can bind to the overexpressed transferrin (Tf) on the surfaces of BBB and GBM, enabling the NCs to target BBB and GBM cells and rely on the TfR mediated intracellular pathway to penetrate BBB (Fig. 7C). This evidence concerns the gene TFRC and glioblastoma.