Fibroblast Activation Protein Inhibitor-Based Radionuclide Therapies: Current Status and Future Directions

J Nucl Med. 2023 Jul;64(7):1001-1008. doi: 10.2967/jnumed.123.265594. Epub 2023 Jun 2.

Abstract

Metastatic malignancies have limited management strategies and variable treatment responses. Cancer cells develop beside and depend on the complex tumor microenvironment. Cancer-associated fibroblasts, with their complex interaction with tumor and immune cells, are involved in various steps of tumorigenesis, such as growth, invasion, metastasis, and treatment resistance. Prooncogenic cancer-associated fibroblasts emerged as attractive therapeutic targets. However, clinical trials have achieved suboptimal success. Fibroblast activation protein (FAP) inhibitor-based molecular imaging has shown encouraging results in cancer diagnosis, making them innovative targets for FAP inhibitor-based radionuclide therapies. This review summarizes the results of preclinical and clinical FAP-based radionuclide therapies. We will describe advances and FAP molecule modification in this novel therapy, as well as its dosimetry, safety profile, and efficacy. This summary may guide future research directions and optimize clinical decision-making in this emerging field.

Keywords: FAPI; PET/CT; cancer management; cancer-associated fibroblasts; fibroblast activation protein; radionuclide therapy.

Publication types

  • Review

MeSH terms

  • Cancer-Associated Fibroblasts* / metabolism
  • Fibroblasts / pathology
  • Gallium Radioisotopes
  • Humans
  • Membrane Proteins / metabolism
  • Neoplasms* / diagnostic imaging
  • Neoplasms* / metabolism
  • Neoplasms* / radiotherapy
  • Positron Emission Tomography Computed Tomography
  • Radioisotopes / metabolism
  • Radioisotopes / therapeutic use
  • Serine Endopeptidases / metabolism
  • Tumor Microenvironment

Substances

  • Serine Endopeptidases
  • Membrane Proteins
  • Radioisotopes
  • Gallium Radioisotopes