To better simulate the tumour microenvironment, 20 ng/mL of TNF‐α known to induce overexpression of cell adhesion molecules in endothelial cells of the BBB was added.20 The transcytosis ability of GNPs alone and loaded in macrophages was compared by monitoring the loss in Calcein Blue fluorescence of U251 cells. The gene discussed is TNF; the disease is neoplasm.