Figure 5. Representative examples of enhanced nanoparticle targeting to EGF receptors using EGF receptor-selective peptides.
(Ai–iv) Fluorescence images indicate that peptide-decorated EGF receptor (EGFR)-targeted micelles undergo significantly higher internalization in (Aii) EGFR-overexpressing A431 cells compared with the same formulation in (Aiv) EGFR-deficient MCF-7c3 cells, while (Ai & iii) the nontargeted formulation undergoes very little internalization in either cell line at the incubation time points studied. (Av) Quantitative assessment of drug uptake following incubation with EGFR-targeted versus nontargeted formulations shows significantly higher uptake with the targeted formulation along with subsequent higher cell death as seen through live/dead fluorescence images (Avii) (green: live; red: dead), compared with the nontargeted formulation (Avi). (B) Biodistribution data in the (Bi) plasma and (Bii) tumor of peptide-decorated EGFR-targeted polymer blend NPs delivering LON and PTX show much higher tumor-specific uptake and reduced nonspecific uptake compared with nontargeted formulations. (Biii) NP formulations significantly improved tumor suppression compared with free drug.
*p < 0.05; **p < 0.01.
LON: Loninadine; NP: Nanoparticle; PTX: Paclitaxel.