Specific imaging of VEGF-A expression with radiolabeled anti-VEGF monoclonal antibody

Int J Cancer. 2008 May 15;122(10):2310-4. doi: 10.1002/ijc.23404.


Vascular endothelial growth factor-A (VEGF-A) is one of the most important angiogenic factors. Here, we studied in a nude mouse model whether the expression of VEGF-A in a tumor could be imaged with a radiolabeled anti-VEGF antibody. The humanized anti-VEGF-A antibody A.4.6.1. (bevacizumab), which is reactive with all VEGF-A isoforms, was radiolabeled with In-111 or with I-125. The accumulation of the radiolabeled antibodies in VEGF-A expressing tumors (LS174T) in nude mice was examined in biodistribution studies and by gamma camera imaging. The uptake of the In-111-bevacizumab in the tumor at 3 days p.i. was significantly higher than that of I-125-bevacizumab (19.4 +/- 7.0 %ID/g vs. 9.6 +/- 3.3 %ID/g, p = 0.04). Coinjection of an excess unlabeled antibody resulted in a significant decrease in radioactivity concentration in the tumor (<2.9 +/- 1.9 %ID/g, p < 0.005), indicating VEGF-mediated antibody uptake. Highest uptake in the tumor was observed at relatively low antibody protein doses (<3 microg) (20-25 %ID/g). VEGF-A-expressing tumors could be clearly visualized on planar scintigraphic images from 24-hr post injection onwards. In conclusion, VEGF-A expression in tumors can be visualized specifically with radiolabeled anti-VEGF-A-mAb.

MeSH terms

  • Angiogenesis Inhibitors*
  • Animals
  • Antibodies, Monoclonal*
  • Antibodies, Monoclonal, Humanized
  • Bevacizumab
  • Colonic Neoplasms / chemistry*
  • Colonic Neoplasms / diagnostic imaging
  • Colonic Neoplasms / pathology
  • Humans
  • Immunoenzyme Techniques
  • Indium Radioisotopes*
  • Iodine Radioisotopes*
  • Male
  • Mice
  • Mice, Inbred BALB C
  • Mice, Nude
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Radionuclide Imaging
  • Reverse Transcriptase Polymerase Chain Reaction
  • Tissue Distribution
  • Vascular Endothelial Growth Factor A / analysis*
  • Xenograft Model Antitumor Assays


  • Angiogenesis Inhibitors
  • Antibodies, Monoclonal
  • Antibodies, Monoclonal, Humanized
  • Indium Radioisotopes
  • Iodine Radioisotopes
  • RNA, Messenger
  • Vascular Endothelial Growth Factor A
  • vascular endothelial growth factor A, mouse
  • Bevacizumab