Due to the excellent BBB penetration and OTX accumulation in GBM (7.6% of injected dose (ID), Figure 3I), the level of dendritic cells in lymph node and anti‐tumor T cells (CD4+ and CD8+) in blood and tumor microenvironment were significantly increased (Figure 2), leading to significantly synergistic GBM treatment in GL261 GBM bearing mice. Here, CD4 is linked to neoplasm.