# GRPR (gastrin-releasing peptide receptor)

Source: https://nuclide.cc/targets/grpr/  
Nuclide record `grpr` (Target). Data CC BY-NC 4.0, attribute "Data from Nuclide (nuclide.cc)"; commercial use needs a licence.

## TL;DR

GRPR is a hormone receptor abundant in early and hormone-sensitive prostate cancer, imaged and treated with bombesin-like radioligands.

## Summary

The gastrin-releasing peptide receptor (GRPR) is a G-protein-coupled receptor for bombesin and GRP whose expression is high in hormone-sensitive prostate cancer and falls with castration resistance. It is overexpressed in primary and hormone-naive prostate cancer, often in PSMA-negative tumours, as well as in ER-positive breast cancer and GIST, which makes it a complementary theranostic target to PSMA. Bombesin-like radioligands exploit it: 68Ga-RM2 PET for imaging and 177Lu-NeoB (Novartis) for therapy are in clinical trials. Because expression declines as disease becomes castration-resistant, GRPR agents may suit earlier disease or PSMA-negative patients rather than replacing PSMA therapy. A newcomer can think of GRPR as a second radioactive address on prostate cancer, useful where PSMA is dim.

## Fields

- Kind: Target
- Last checked: 2026-09-06
- Tags: theranostic
- Symbol: GRPR
- Class: surface-antigen
- Biology: G-protein-coupled receptor for bombesin/GRP; expression falls with castration resistance.
- Where found: Hormone-sensitive prostate cancer; ER+ breast cancer; GIST

## Sources

- Wikipedia: https://en.wikipedia.org/wiki/Gastrin-releasing_peptide_receptor
- Wikipedia: https://en.wikipedia.org/wiki/Gastrin-releasing_peptide_receptor

## Connected records

- isotopes: [Gallium-68](https://nuclide.cc/isotopes/ga-68/), [Lutetium-177](https://nuclide.cc/isotopes/lu-177/)
- indications: [Prostate cancer](https://nuclide.cc/indications/prostate/)
- technologies: [PET (positron emission tomography)](https://nuclide.cc/technologies/pet/), [Radioligand therapy (beta emitters)](https://nuclide.cc/technologies/radioligand-therapy/)
- opportunities: [GRPR imaging when the PSMA scan is negative](https://nuclide.cc/opportunities/opp-grpr-psma-negative-prostate/)
- companies: [Life Molecular Imaging](https://nuclide.cc/companies/life-molecular-imaging/)
- ideas: [Bispecific PSMA/GRPR radioligands for discordant prostate cancer lesions](https://nuclide.cc/ideas/idea-bispecific-radioligands/)
- targets: [Bradykinin B1 receptor (B1R)](https://nuclide.cc/targets/bradykinin-b1-receptor/)

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JSON: https://nuclide.cc/api/v1/entities/grpr.json