Since TFRC is highly expressed in BBB vECs [268, 269] and brain tumors such as glioblastomas [271–273], nanoparticles targeted with TFRC-binding peptides have been explored as diagnostic probes for imaging brain tumors [274, 275] and for boosting brain uptake of therapeutic antibodies [276–278]. The gene discussed is TFRC; the disease is glioblastoma.