One potential hypothesis to account for the observed sequestration into orthotopic gliomas proposes that Angiopep-2 conjugates, after penetrating the BBB, interact again with tumour-bound LRP1, which is known to be prevalent in glial lineages (Lillis et al, 2005), and subsequently enter the individual cells by endocytosis. The gene discussed is LRP1; the disease is central nervous system cancer.