title: Targeted near-IR hybrid magnetic nanoparticles for in vivo cancer therapy and imaging.
abstract: We report the use of immuno-targeted gold-iron oxide hybrid nanoparticles for laser-assisted therapy and for MRI-based imaging as demonstrated in xenograft colorectal cancer tumor model. Immuno-targeted gold-iron oxide nanoparticles selectively accumulate in SW1222 xenograft tumors as compared to the accumulation in non-antigen-expressing tumor xenografts. Effective photothermal treatment using near-IR laser irradiation (808nm, 5W cm(-2)) application is shown where >65% of the antigen-expressing tumor cells presented corrupt extracellular matrix and cytoplasmic acidophilia suggesting effectiveness of nanoparticle-assisted thermal therapy. Cell killing was confirmed by hematoxylin and eosin (H&E) histological staining where scar-like structure containing collagen bundles was observed in the treatment group. Further, systemically injected HNPs were shown to be effective T2 magnetic resonance (MR) imaging contrast agents, localized and detected at the antigen-expressing xenograft tumors. These findings suggest that the new class of bio-conjugated HNPs exhibits great potential for dual-therapy and diagnostics (theranostics) applications.
  
  
  BACKGROUND
  This team reports the successful use of immuno-targeted gold-iron oxide hybrid nanoparticles for both laser-assisted therapy and MRI-based imaging in a xenograft colorectal cancer tumor model, demonstrating strong potentials for dual applications in cancer diagnosis and therapy.
authors.affiliation: Graduate Field of Biomedical Engineering, 318 Stocking Hall, Cornell University, Ithaca, New York, USA. dk322@cornell.edu
authors.forename: Dickson K
authors.initials: DK
authors.lastname: Kirui
authors.forename: Ildar
authors.initials: I
authors.lastname: Khalidov
authors.forename: Yi
authors.initials: Y
authors.lastname: Wang
authors.forename: Carl A
authors.initials: CA
authors.lastname: Batt
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000188:drug therapy* / Q000473:pathology; D003287:Contrast Media / Q000008:administration & dosage / Q000737:chemistry; D003952:Diagnostic Imaging; D005290:Ferric Compounds / Q000008:administration & dosage / Q000737:chemistry; D006046:Gold / Q000008:administration & dosage / Q000737:chemistry; D006801:Humans; D028022:Low-Level Light Therapy; D008279:Magnetic Resonance Imaging / Q000379:methods; D058185:Magnetite Nanoparticles / Q000008:administration & dosage* / Q000737:chemistry; D051379:Mice; D023041:Xenograft Model Antitumor Assays
chemical_list: D003287:Contrast Media; D005290:Ferric Compounds; D058185:Magnetite Nanoparticles; C000499:ferric oxide; D006046:Gold