The antitumor mechanism of cEM@DEP‐siRNA is as follow: after administered to DIPG orthotopic xenograft model by tail intravenous injection, cEM@DEP‐siRNA could penetrate the blood–brain barrier by the function of EXO, and accumulates at the tumor site and uptaken by DIPG cells by cRGD, then release panobinostat and PPM1D siRNA by endosome escape. This evidence concerns the gene PPM1D and neoplasm.