Development of anti-EGF receptor peptidomimetics (AERP) as tumor imaging agent.

EGFR is over-expressed in several solid tumors including breast, prostate, pancreas, and lung cancers and is correlated to the metastatic potential of the tumor. Anti-EGFR receptor-binding peptidomimetics (AERP) were examined to assess the small molecule's potential use as tumor-specific imaging agents. The aim of this work was to design and characterize the binding specificity of the radiolabeled peptidomimetics to EGFR over-expressing cell lysate and to A431 xenograft tumors. Our newly designed peptidomimetic, AERP, was conjugated to DTPA and labeled with (99m)Tc. The in vivo tumor accumulation of [(99m)Tc] DTPA-AERP-2 was 1.6±0.1%ID/g and tumor to muscle ratio was 5.5. Our studies suggest that this novel peptidomimetic, AERP-2, warrants further development as an EGFR specific tumor-imaging agent.