{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,13]],"date-time":"2026-06-13T15:40:06Z","timestamp":1781365206903,"version":"3.54.1"},"reference-count":38,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2021,2,9]],"date-time":"2021-02-09T00:00:00Z","timestamp":1612828800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>The cholecystokinin-2 receptor (CCK-2R) is overexpressed in several human cancers but displays limited expression in normal tissues. For this reason, it is a suitable target for developing specific radiotracers. In this study, a nastorazepide-based ligand functionalized with a 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) chelator (IP-001) was synthesized and labelled with indium-111. The radiolabeling process yielded &gt;95% with a molar activity of 10 MBq\/nmol and a radiochemical purity of &gt;98%. Stability studies have shown a remarkable resistance to degradation (&gt;93%) within 120 h of incubation in human blood. The in vitro uptake of [111In]In-IP-001 was assessed for up to 24 h on a high CCK-2R-expressing tumor cell line (A549) showing maximal accumulation after 4 h of incubation. Biodistribution and single photon emission tomography (SPECT)\/CT imaging were evaluated on BALB\/c nude mice bearing A549 xenograft tumors. Implanted tumors could be clearly visualized after only 4 h post injection (2.36 \u00b1 0.26% ID\/cc), although a high amount of radiotracer was also found in the liver, kidneys, and spleen (8.25 \u00b1 2.21%, 6.99 \u00b1 0.97%, and 3.88 \u00b1 0.36% ID\/cc, respectively). Clearance was slow by both hepatobiliary and renal excretion. Tumor retention persisted for up to 24 h, with the tumor to organs ratio increasing over-time and ending with a tumor uptake (1.52 \u00b1 0.71% ID\/cc) comparable to liver and kidneys.<\/jats:p>","DOI":"10.3390\/molecules26040918","type":"journal-article","created":{"date-parts":[[2021,2,14]],"date-time":"2021-02-14T02:08:12Z","timestamp":1613268492000},"page":"918","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Preliminary Study of a 1,5-Benzodiazepine-Derivative Labelled with Indium-111 for CCK-2 Receptor Targeting"],"prefix":"10.3390","volume":"26","author":[{"given":"Marco","family":"Verona","sequence":"first","affiliation":[{"name":"Department of Pharmaceutical Sciences, University of Padova, via Marzolo 5, 35131 Padova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sara","family":"Rubagotti","sequence":"additional","affiliation":[{"name":"Radiopharmaceutical Chemistry Section, Nuclear Medicine Unit, AUSL-IRCCS di Reggio Emilia, Viale Risorgimento 80, 42122 Reggio Emilia, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8622-0439","authenticated-orcid":false,"given":"Stefania","family":"Croci","sequence":"additional","affiliation":[{"name":"Clinical Immunology, Allergy, and Advanced Biotechnologies Unit, Diagnostic Imaging and Laboratory Medicine Department, AUSL-IRCCS di Reggio Emilia, Viale Risorgimento 80, 42122 Reggio Emilia, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4323-3165","authenticated-orcid":false,"given":"Sophia","family":"Sarpaki","sequence":"additional","affiliation":[{"name":"Bioemtech, Lefkippos Attica Technology Park N.C.S.R. \u201cDEMOKRITOS\u201d Patr. Gregoriou E &amp; 27 Neapoleos Str. Ag. Paraskevi, 15341 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Francesca","family":"Borgna","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Sciences, University of Padova, via Marzolo 5, 35131 Padova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3726-6174","authenticated-orcid":false,"given":"Marianna","family":"Tosato","sequence":"additional","affiliation":[{"name":"Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131 Padova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elisa","family":"Vettorato","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Sciences, University of Padova, via Marzolo 5, 35131 Padova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5892-5992","authenticated-orcid":false,"given":"Giovanni","family":"Marzaro","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Sciences, University of Padova, via Marzolo 5, 35131 Padova, Italy"},{"name":"Legnaro National Laboratories, Italian Institute of Nuclear Physics, Viale dell\u2019Universit\u00e0 2, 35020 Legnaro (Padova), Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2499-5490","authenticated-orcid":false,"given":"Francesca","family":"Mastrotto","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Sciences, University of Padova, via Marzolo 5, 35131 Padova, Italy"},{"name":"Legnaro National Laboratories, Italian Institute of Nuclear Physics, Viale dell\u2019Universit\u00e0 2, 35020 Legnaro (Padova), Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mattia","family":"Asti","sequence":"additional","affiliation":[{"name":"Radiopharmaceutical Chemistry Section, Nuclear Medicine Unit, AUSL-IRCCS di Reggio Emilia, Viale Risorgimento 80, 42122 Reggio Emilia, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,2,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Tafreshi, N.K., Doligalski, M.L., Tichacek, C.J., Pandya, D.N., Budzevich, M.M., El-Haddad, G., Khushalani, N.I., Moros, E.G., McLaughlin, M.L., and Wadas, T.J. 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