{"entity": "publication", "iuid": "7c4c340c7b2248789c648fbbb1c2ef0e", "timestamp": "2026-08-22T07:48:01.248Z", "links": {"self": {"href": "https://publications-affiliated.scilifelab.se/publication/7c4c340c7b2248789c648fbbb1c2ef0e.json"}, "display": {"href": "https://publications-affiliated.scilifelab.se/publication/7c4c340c7b2248789c648fbbb1c2ef0e"}}, "title": "Preclinical Evaluation of the Copper-64 Labeled GRPR-Antagonist RM26 in Comparison with the Cobalt-55 Labeled Counterpart for PET-Imaging of Prostate Cancer.", "authors": [{"family": "Baun", "given": "Christina", "initials": "C", "orcid": "0000-0002-5199-9200", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/484f3234a1a143c38b832f22c73d1d59.json"}}, {"family": "Mitran", "given": "Bogdan", "initials": "B"}, {"family": "Rinne", "given": "Sara S", "initials": "SS", "orcid": "0000-0003-2141-3982", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/3aea3edd98b441c98bb527b1e0c911f5.json"}}, {"family": "Dam", "given": "Johan H", "initials": "JH", "orcid": "0000-0001-6577-7011", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/8495e80a9bd54345a3d18eaf987f9dd5.json"}}, {"family": "Olsen", "given": "Birgitte B", "initials": "BB", "orcid": "0000-0002-6130-0387", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/883bae2a831c459ea60c589df0eb2d4d.json"}}, {"family": "Tolmachev", "given": "Vladimir", "initials": "V", "orcid": "0000-0002-6122-1734", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/896ae9fae8b74251afe11b4354c62794.json"}}, {"family": "Orlova", "given": "Anna", "initials": "A", "orcid": "0000-0001-6120-2683", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/1c374f429702489494c05f84f298b4b7.json"}}, {"family": "Thisgaard", "given": "Helge", "initials": "H", "orcid": "0000-0001-9492-448X", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/43de528e1e1d415bbd9fc1dc5a4285e6.json"}}], "type": "comparative study", "published": "2020-12-18", "journal": {"title": "Molecules", "issn": "1420-3049", "volume": "25", "issue": "24", "issn-l": "1420-3049"}, "abstract": "Gastrin-releasing peptide receptor (GRPR) is overexpressed in the majority of prostate cancers. This study aimed to investigate the potential of 64Cu (radionuclide for late time-point PET-imaging) for imaging of GRPR expression using NOTA-PEG2-RM26 and NODAGA-PEG2-RM26. Methods: NOTA/NODAGA-PEG2-RM26 were labeled with 64Cu and evaluated in GRPR-expressing PC-3 cells. Biodistribution of [64Cu]Cu-NOTA/NODAGA-PEG2-RM26 was studied in PC-3 xenografted mice and compared to the biodistribution of [57Co]Co-NOTA/NODAGA-PEG2-RM26 at 3 and 24 h p.i. Preclinical PET/CT imaging was performed in tumor-bearing mice. NOTA/NODAGA-PEG2-RM26 were stably labeled with 64Cu with quantitative yields. In vitro, binding of [64Cu]Cu-NOTA/NODAGA-PEG2-RM26 was rapid and GRPR-specific with slow internalization. In vivo, [64Cu]Cu-NOTA/NODAGA-PEG2-RM26 bound specifically to GRPR-expressing tumors with fast clearance from blood and normal organs and displayed generally comparable biodistribution profiles to [57Co]Co-NOTA/NODAGA-PEG2-RM26; tumor uptake exceeded normal tissue uptake 3 h p.i.. Tumor-to-organ ratios did not increase significantly with time. [64Cu]Cu-NOTA-PEG2-RM26 had a significantly higher liver and pancreas uptake compared to other agents. 57Co-labeled radioconjugates showed overall higher tumor-to-non-tumor ratios, compared to the 64Cu-labeled counterparts. [64Cu]Cu-NOTA/NODAGA-PEG2-RM26 was able to visualize GRPR-expression in a murine PC model using PET. However, [55/57Co]Co-NOTA/NODAGA-PEG2-RM26 provided better in vivo stability and overall higher tumor-to-non-tumor ratios compared with the 64Cu-labeled conjugates.", "doi": "10.3390/molecules25245993", "pmid": "33352838", "labels": [], "xrefs": [{"db": "pmc", "key": "PMC7766840"}, {"db": "pii", "key": "molecules25245993"}], "notes": [], "created": "2026-08-21T13:04:26.638Z", "modified": "2026-08-21T13:04:26.801Z"}