To address the impact of the blood-brain barrier, as well as the hypoxic microenvironment, on the treatment of glioblastoma, Wu et al. generated a silica nanoparticle encapsulating catalase (CAT@SiO2) that adheres to exosomes derived from macrophages, thus forming CSI@Ex-A, which exhibits remarkable blood-brain barrier penetration and adept targeting of cancer cells [88]. This evidence concerns the gene CAT and cancer.