Peptide-based imaging agents for cancer detection

Abstract

Selective receptor-targeting peptide based agents have attracted considerable attention in molecular imaging of tumor cells that overexpress corresponding peptide receptors due to their unique properties such as rapid clearance from circulation as well as high affinities and specificities for their targets. The rapid growth of chemistry modification techniques has enabled the design and development of various peptide-based imaging agents with enhanced metabolic stability, favorable pharmacokinetics, improved binding affinity and selectivity, better imaging ability as well as biosafety. Among them, many radiolabeled peptides have already been translated into the clinic with impressive diagnostic accuracy and sensitivity. This review summarizes the current status in the development of peptide-based imaging agents with an emphasis on the consideration of probe design including the identification of suitable peptides, the chemical modification of probes and the criteria for clinical translation. Specific examples in clinical trials have been provided as well with respect to their diagnostic capability compared with other FDA approved imaging agents.

Rapid PD-L1 detection in tumors with PET using a highly specific peptide

“…The dynamic nature of the tumor immune microenvironment provides rationale for development of PET tracers that allow for rapid evaluation of TME. In this regard, low molecular weight, peptide-based PET tracers are desirable candidates for clinical application due to their fast clearance and synthetic tractability[15]. Peptide-based PET tracers targeting somatostatin receptors and chemokine receptor 4 (CXCR4) produce high target-to-non-target ratios in patients[16].…”

Peptide-Based 68Ga-PET Radiotracer for Imaging PD-L1 Expression in Cancer

“…Not surprisingly, most routinely used clinical radiopharmaceuticals, particularly for PET, are either peptides or low-molecular-weight agents. 16 …”

Radiolabeled bombesin derivatives for preclinical oncological imaging

“…For example, several peptide receptors have been identified as overexpressed components on tumor cells surface when compared to their expression in normal cells (Table 1). Thus, many peptides and their derivatives have been radiolabeled and investigated as potential cancer diagnostic agents for molecular imaging by SPECT and PET [8–11]. …”