Imaging the Distribution of Gastrin-Releasing Peptide Receptors in Cancer

Targeting tumor-expressed receptors using selective molecules for diagnostic, therapeutic, or both diagnostic and therapeutic (theragnostic) purposes is a promising approach in oncologic applications. Such approaches have increased significantly over the past decade. Peptides such as gastrin-releasing peptide receptors targeting radiopharmaceuticals are small molecules with fast blood clearance and urinary excretion. They demonstrate good tissue diffusion, low immunogenicity, and highly selective binding to their target cell-surface receptors. They are also easily produced. Gastrin-releasing peptide receptors, part of the bombesin family, are overexpressed in many tumors, including breast and prostate cancer, and therefore represent an attractive target for future development.