Peptide ligand-mediated liposome distribution and targeting to EGFR expressing tumor in vivo.

Epidermal growth factor receptor (EGFR) is an important anti-cancer therapy target that is applicable to many cancer types. We had previously reported the screening and discovery of a novel peptide ligand against EGFR named GE11. It was shown to bind to EGFR competitively with EGF and mediate gene delivery to cancer cells with high-EGFR expression. In this study, we conjugated GE11 on to liposome surface and examined their binding and distribution to EGFR expressing cancer cells in vitro and in vivo using fluorescence imaging techniques. GE11 liposomes were found to bind specifically and efficiently to EGFR high-expressing cancer cells. In vivo in H1299 xenograft mouse model, GE11 liposomes also extravasated and accumulated into the tumor site preferentially, and demonstrated better targeting and drug delivery capacities.