Tumor uptake was higherfor the LNCaP tumors than for PC-3 tumors, which can be attributedto the higher expression of PSMA in LNCaP cells in comparison to thatof GRPR in PC-3 cells (levels of expression: PSMA, 1.26–1.8× 105 per LNCaP; GRPR, 9.7 × 104 perPC-3 cell)58−60 In addition, the amount of [68Ga]Ga-3 inside the LNCaP tumors did not degrade as fast as the onein the PC-3 tumors, possibly because of the higher rates of internalizationfor the PSMA ligand–receptor complexes compared to the GRPRantagonist complexes. This evidence concerns the gene GRPR and neoplasm.