Alpha melanocyte stimulating hormone (α-MSH) enhances melanogenesis in melanoma malignum by binding to melanocortin-1 receptors (MC1-R). Earlier studies demonstrated that alpha-MSH analog NAPamide molecule specifically binds to MC1-R receptor. Radiolabeled NAPamide is a promising radiotracer for the non-invasive detection of melanin producing melanoma tumors by Positron Emission Tomography (PET). In this present study the MC1-R selectivity of the newly developed Sc-44-labeled DOTA-NAPamide was investigated in vitro and in vivo using melanoma tumors.DOTA-NAPamide was labeled with Ga-68 and Sc-44 radionuclides. The MC1-R specificity of Ga-68- and Sc-44-labeled DOTA-NAPamide was investigated in vitro and in vivo using MC1-R positive (B16-F10) and negative (A375) melanoma cell lines. For in vivo imaging studies B16-F10 and A375 tumor-bearing mice were injected with 44Sc/68Ga-DOTA-NAPamide (in blocking studies with α-MSH) and whole body PET/MRI scans were acquired. Radiotracer uptake was expressed in terms of standardized uptake values (SUVs).44Sc/68Ga-labeled DOTA-NAPamide were produced with high specific activity (approx. 19 GBq/μmol) and with excellent radiochemical purity (99

作者：Gábor, Nagy；Noémi, Dénes；Adrienn, Kis；Judit P, Szabó；Ervin, Berényi；Ildikó, Garai；Péter, Bai；István, Hajdu；Dezs?, Szikra；Gy?rgy, Trencsényi

来源：European journal of pharmaceutical sciences : official journal of the European Federation for Pharmaceutical Sciences 2017 年 106卷