GRPR and Familial prostate cancer: In another study, in which the molecular target was the gastrin-releasing peptide receptor (GRPR), which is highly expressed in tumors like prostate cancer, a complex made of the pair of radionuclides 64Cu/67Cu, a bombesin (BBN) analogue, and a sarcophagine-based amine was used in a PC-3 xenograft prostate cancer mouse model.