Purpose: Cell-surface receptor-targeted magnetic iron oxide nanoparticles provide molecular magnetic resonance imaging contrast agents for improving specificity of the detection of human cancer. Experimental Design:The present study reports the development of a novel targeted iron oxide nanoparticle using a recombinant peptide containing the amino-terminal fragment of urokinasetype plasminogen activator (uPA) conjugated tomagnetic ironoxide nanoparticles amino-terminal fragment conjugated-iron oxide (ATF-IO).This nanoparticle targets uPA receptor,which is overexpressedinbreast cancer tissues. Results: ATF-IO nanoparticles are able to specifically bind to and be internalized by uPA receptor - expressing tumor cells. Systemic delivery of ATF-IO nanoparticles into mice bearing s.c. and i.p. mammary tumors leads to the accumulation of the particles in tumors, generating a strongmagnetic resonance imaging contrast detectable by a clinicalmagnetic resonance imaging scanner at a field strength of 3 tesla.Target specificity of ATF-IOnanoparticles showed by in vivo magnetic resonance imaging is further confirmed by near-IR fluorescence imaging of the mammary tumors using near-IR dye-labeled amino-terminal fragment peptides conjugated to iron oxide nanoparticles. Furthermore, mice administered ATF-IO nanoparticles exhibit lower uptake of the particles in the liver and spleen compared with those receiving nontargeted iron oxide nanoparticles.
ASJC Scopus subject areas
- Cancer Research