Selective uptake and imaging of aptamer- and antibody-conjugated hollow nanospheres targeted to epidermal growth factor receptors overexpressed in head and neck cancer

ACS Nano. 2014 May 27;8(5):4530-8. doi: 10.1021/nn406632u. Epub 2014 Apr 24.

Abstract

The purpose of this study was to compare the binding affinity and selective targeting of aptamer- and antibody-coated hollow gold nanospheres (HAuNS) targeted to epidermal growth factor receptors (EGFR). EGFR-targeting aptamers were conjugated to HAuNS (apt-HAuNS) by attaching a thiol-terminated single-stranded DNA to the HAuNS and then adding the complementary RNA targeted to EGFR. Apt-HAuNS was characterized in terms of size, surface charge, absorption, and number of aptamers per particle. The in vivo pharmacokinetics, in vivo biodistribution, and micro-SPECT/CT imaging of (111)In-labeled apt-HAuNS and anti-EGFR antibody (C225)-conjugated HAuNS were evaluated in nude mice bearing highly malignant human OSC-19 oral tumors. (111)In-labeled PEG-HAuNS was used as a control (n = 5/group). Apt-HAuNS did not have an altered absorbance profile or size (λmax = 800 nm; diameter = 55 nm) compared to C225-HAuNS or PEG-HAuNS. The surface charge became more negative upon conjugation of the aptamer (-51.4 vs -19.0 for PEG-HAuNS and -25.0 for C225-HAuNS). The number of aptamers/particle was ∼250. In vitro cell binding and in vivo biodistribution showed selective binding of the apt-HAuNS to EGFR. μSPECT/CT imaging confirmed that there was more tumor uptake of apt-HAuNS than C225-HAuNS. Aptamer is a promising ligand for image-guided delivery of nanoparticles for treatment of tumor cells overexpressing EGFR.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Antibodies / chemistry*
  • Area Under Curve
  • Carcinoma, Squamous Cell / metabolism
  • DNA, Single-Stranded / chemistry
  • ErbB Receptors / chemistry*
  • Gold / chemistry*
  • Head and Neck Neoplasms / drug therapy*
  • Humans
  • Ligands
  • Male
  • Metal Nanoparticles / chemistry*
  • Mice
  • Mice, Nude
  • Nanospheres / chemistry*
  • Nanotechnology / methods
  • Neoplasm Transplantation
  • Polyethylene Glycols / chemistry
  • Protein Binding
  • Tomography, Emission-Computed, Single-Photon
  • Tomography, X-Ray Computed

Substances

  • Antibodies
  • DNA, Single-Stranded
  • Ligands
  • Polyethylene Glycols
  • Gold
  • ErbB Receptors