(A) Schematic representation of lentiviral transfer vectors comprising eGFP, anti-EGFR nanobodies (LV-ENb2) and cytotoxic TRAIL (LV-ENb2-TRAIL). (B) ELISA showing EGFR competition by ENb2-TRAIL. (C) Western blot analysis showing inhibition of EGFR and downstream signaling via the AKT and MAPK pathways on serum-starved Her14 cells incubated with ENb2-TRAIL. (D) Photomicrographs of H&E stained sections and tumor volumes from the brains of GBM-bearing mice treated with NSC-GFP, NSC-ENb2, and NSC-ENb2-TRAIL. (E) Kaplan-Meier survival curves of mice bearing established tumors and implanted with NSC expressing GFP, ENb2 or ENb2-TRAIL intratumorally (n=5 per group). (F) Representative fluorescent images and plot showing the number of GBM8-mCherry invading cells 7 days after NSC-GFP, NSC-ENb2, and NSC-ENb2-TRAIL treatment. Data represented as mean ± SEM, * denotes P< 0.05, Student’s t test. White lines indicate the wall of the lateral ventricle. eGFP, Enhanced green fluorescent protein. Adapted with permission from[70].