GRPR and prostate intraepithelial neoplasia: In 34 PIN specimens, strong and moderate GRPR-, PSMA-, and NTR1-positive expression was observed (79.4%, 32.4%, and 2.9%, respectively) (Table 1; Fig. 2), and the expression of GRPR was significantly higher than those of NTR1 and PSMA (P < 0.05).