Gastrin-Releasing Peptide Receptor in Low Grade Prostate Cancer: Can It Be a Better Predictor Than Prostate-Specific Membrane Antigen?

Pinuccia Faviana; Laura Boldrini; Paola Anna Erba; Iosè Di Stefano; Francesca Manassero; Riccardo Bartoletti; Luca Galli; Carlo Gentile; Massimo Bardi

doi:10.3389/fonc.2021.650249

Gastrin-Releasing Peptide Receptor in Low Grade Prostate Cancer: Can It Be a Better Predictor Than Prostate-Specific Membrane Antigen?

Front Oncol. 2021 Mar 29:11:650249. doi: 10.3389/fonc.2021.650249. eCollection 2021.

Authors

Pinuccia Faviana¹, Laura Boldrini¹, Paola Anna Erba², Iosè Di Stefano¹, Francesca Manassero², Riccardo Bartoletti², Luca Galli², Carlo Gentile¹, Massimo Bardi³

Affiliations

¹ Department of Surgical, Medical, Molecular Pathology and Critical Area, University of Pisa, Pisa, Italy.
² Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy.
³ Department of Psychology and Behavioral Neuroscience, Randolph-Macon College, Ashland, VA, United States.

Abstract

The aim of the present study was to evaluate whether prostate cancer (PC) patients can be accurately classified on the bases of tissue expression of gastrin-releasing peptide receptor (GRPR) and prostate-specific membrane antigen (PSMA). This retrospective study included 28 patients with PC. Formalin-fixed paraffin-embedded samples were used for diagnosis. Immunohistochemistry staining techniques were used to evaluate PSMA and GRPR expression (both number of cells expressed and % of area stained). To assess the independent associations among selected variables, a multi-dimensional scaling (MDS) analysis was used. It was found that the PSMA expression was inversely correlated with GRPR expression. Only the number of cells expressing GRPR was significantly related to the Gleason score. Both the percentage of area expressing GRPR and the number of cells expressing PSMA were close to reaching significance at the 0.05 level. MDS provided a map of the overall, independent association confirming that GRPR and PSMA represent inversely correlated measures of the same dimension. In conclusion, our data showed that GRPR expression should be evaluated in prostate biopsy specimens to improve our ability to detect PC with low grades at the earliest phases of development. Considering that GRPRs appear to be directly involved in the mechanisms of tumor proliferation, advancements in nuclear medicine radiotherapy can focus on this receptor to improve the therapeutic approach to PC. Further studies in our laboratory will investigate the molecular mechanisms of activation based on GRPR.

Keywords: Gleason score; gastrin-releasing peptide receptor (GRPR); multi-dimensional scaling (MDS); prostate cancer; prostate-specific membrane antigen (PSMA).