Radiolabeled NGR phage display peptide sequence for tumor targeting

• Asparagine–glycine–arginine (NGR) peptide is a marker of angiogenesis.
• Radiolabeled NGR was evaluated in different experimental tumor lines.
• Encouraging results were reached with lung and ovarian cancer cells.
• The radiotracer is a candidate for diagnostic application.

The asparagine–glycine–arginine (NGR) peptide sequence found by phage display, was radiolabeled with technetium-99m and tested in different tumor models. Similar uptake occurred with ovarian and lung tumor cells. Biodistribution of the radiotracer revealed predominant renal excretion with more substantial uptake in animals bearing ovarian tumor cells. In contrast imaging studies indicated better visualization for lung tumor. NGR peptide was characterized as a promising diagnostic candidate, particularly for lung cancer. Improvements are envisaged using NGR combined with RGD as a heterodimer molecule.