title: Arginine-glycine-aspartic acid (RGD)-peptide binds to both tumor and tumor-endothelial cells in vivo.
abstract: Targeting tumor cells or tumor vasculature by peptides is a promising strategy for delivering cytotoxic drugs for cancer therapy. The identification of efficient targeting peptides depends on the availability of informative methods for determining cellular binding specificities. Here, we have used fluorescence-activated cell-sorting (FACS) analysis in combination with an isopentane freezing method to show targeted binding of the Arg-Gly-Asp (RGD)-4C-peptide labeled with FITC, not only to endothelial cells but also to tumor cells in human breast cancer xenografts grown in nude mice. Nontumorous cells showed only background binding. This study suggests, that the RGD-4C-peptide can target tumor endothelial cells as well as tumor cells. Consequently, it should be possible to design a combination therapy approach against both targets.
authors.affiliation: Department for Cytogenetics H0400, German Cancer Research Center, Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany.
authors.forename: Sabine
authors.initials: S
authors.lastname: Zitzmann
authors.forename: Volker
authors.initials: V
authors.lastname: Ehemann
authors.forename: Manfred
authors.initials: M
authors.lastname: Schwab
mesh_terms: D000818:Animals; D001943:Breast Neoplasms / Q000098:blood supply / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000378:metabolism*; D005260:Female; D005434:Flow Cytometry; D016650:Fluorescein-5-isothiocyanate; D005456:Fluorescent Dyes; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D009842:Oligopeptides / Q000378:metabolism*; D011485:Protein Binding; D014183:Transplantation, Heterologous; D014407:Tumor Cells, Cultured
chemical_list: D005456:Fluorescent Dyes; D009842:Oligopeptides; C047981:arginyl-glycyl-aspartic acid; D016650:Fluorescein-5-isothiocyanate