{"entity": "publication", "iuid": "d91eca7d475b4743b8c9c96c0f24ea65", "timestamp": "2026-08-28T00:26:22.812Z", "links": {"self": {"href": "https://publications-affiliated.scilifelab.se/publication/d91eca7d475b4743b8c9c96c0f24ea65.json"}, "display": {"href": "https://publications-affiliated.scilifelab.se/publication/d91eca7d475b4743b8c9c96c0f24ea65"}}, "title": "66Ga-PET-imaging of GRPR-expression in prostate cancer: production and characterization of [66Ga]Ga-NOTA-PEG2-RM26.", "authors": [{"family": "Rinne", "given": "Sara S", "initials": "SS"}, {"family": "Abouzayed", "given": "Ayman", "initials": "A"}, {"family": "Gagnon", "given": "Katherine", "initials": "K", "orcid": "0000-0001-6513-8738", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/b70ba33337344e5aaa8c1fb3a4adad7e.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"}}], "type": "journal article", "published": "2021-02-11", "journal": {"title": "Sci Rep", "issn": "2045-2322", "volume": "11", "issue": "1", "pages": "3631", "issn-l": "2045-2322"}, "abstract": "Molecular imaging of the gastrin-releasing peptide receptor (GRPR) could improve patient management in prostate cancer. This study aimed to produce gallium-66 (T\u00bd = 9.5 h) suitable for radiolabeling, and investigate the imaging properties of gallium-66 labeled GRPR-antagonist NOTA-PEG2-RM26 for later-time point PET-imaging of GRPR expression. Gallium-66 was cyclotron-produced using a liquid target, and enriched [66Zn]Zn(NO3)2. In vitro, [66Ga]Ga-NOTA-PEG2-RM26 was characterized in GRPR-expressing PC-3 prostate cancer cells. In vivo, specificity test and biodistribution studies were performed 3 h and 22 h pi in PC-3 xenografted mice. microPET/MR was performed 3 h and 22 h pi. Biodistribution of [66Ga]Ga-NOTA-PEG2-RM26 was compared with [68Ga]Ga-NOTA-PEG2-RM26 3 h pi. [66Ga]Ga-NOTA-PEG2-RM26 was successfully prepared with preserved binding specificity and high affinity towards GRPR. [66Ga]Ga-NOTA-PEG2-RM26 cleared rapidly from blood via kidneys. Tumor uptake was GRPR-specific and exceeded normal organ uptake. Normal tissue clearance was limited, resulting in no improvement of tumor-to-organ ratios with time. Tumors could be clearly visualized using microPET/MR. Gallium-66 was successfully produced and [66Ga]Ga-NOTA-PEG2-RM26 was able to clearly visualize GRPR-expression both shortly after injection and on the next day using PET. However, delayed imaging did not improve contrast for Ga-labeled NOTA-PEG2-RM26.", "doi": "10.1038/s41598-021-82995-7", "pmid": "33574368", "labels": [], "xrefs": [{"db": "pmc", "key": "PMC7878787"}, {"db": "pii", "key": "10.1038/s41598-021-82995-7"}], "notes": [], "created": "2026-08-21T11:53:32.156Z", "modified": "2026-08-21T11:53:32.263Z"}