Identification of a new peptide for fibrosarcoma tumor targeting and imaging in vivo

J Biomed Biotechnol. 2010;2010:167045. doi: 10.1155/2010/167045. Epub 2010 Dec 5.


A 12-mer amino acid peptide SATTHYRLQAAN, denominated TK4, was isolated from a phage-display library with fibrosarcoma tumor-binding activity. In vivo biodistribution analysis of TK4-displaying phage showed a significant increased phage titer in implanted tumor up to 10-fold in comparison with normal tissues after systemic administration in mouse. Competition assay confirmed that the binding of TK4-phage to tumor cells depends on the TK4 peptide. Intravenous injection of (131)I-labeled synthetic TK4 peptide in mice showed a tumor retention of 3.3% and 2.7% ID/g at 1- and 4-hour postinjection, respectively. Tumor-to-muscle ratio was 1.1, 5.7, and 3.2 at 1-, 4-, and 24-hour, respectively, and tumors were imaged on a digital γ-camera at 4-hour postinjection. The present data suggest that TK4 holds promise as a lead structure for tumor targeting, and it could be further applied in the development of diagnostic or therapeutic agent.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Cell Line, Tumor
  • Diagnostic Imaging / methods*
  • Drug Delivery Systems / methods*
  • Female
  • Fibronectins / pharmacology
  • Fibrosarcoma / diagnosis*
  • Fibrosarcoma / metabolism
  • Fibrosarcoma / therapy*
  • Humans
  • Mice
  • Molecular Sequence Data
  • Peptide Library
  • Peptides / analysis*
  • Peptides / chemistry
  • Protein Binding / drug effects
  • Tissue Distribution / drug effects


  • Fibronectins
  • Peptide Library
  • Peptides