Exosomes from bEND.3 cells were able to deliver drugs to a U‐87 MG tumor grown in the brain of zebrafish and were also observed to inhibit VEGF (vascular endothelial growth factor) levels in vivo (Figure 4).35 This, in turn, was able to induce a significant decrease in the tumor size, compared to treatments with the free drug. This evidence concerns the gene VEGFA and neoplasm.