U-87MG cells were engrafted into nude mice brains, and the mice were treated intravenously (i.v.)with PBS/DMSO, free- or PLGA-encapsulated-Retro-Tf-D-LP4, and 20 and 29 days later, tumor growth was monitored by MRI (Figure 7D, 7E and Supplementary Figure 5). The gene discussed is TF; the disease is neoplasm.