Bodin Sacha, Peuker Lisa C, Jestin Emmanuelle, Alves Isabel D, Velasco Valérie, Ait-Arsa Imade, Schollhammer Romain, Lamare Frédéric, Vimont Delphine, MacGrogan Gaétan, Hindié Elif, Beck-Sickinger Annette G, Morgat Clément
Department of Nuclear Medicine, University Hospital of Bordeaux, F-33076 Bordeaux, France.
CNRS, EPHE, INCIA UMR 5287, University of Bordeaux, F-33400 Talence, France.
Bioconjug Chem. 2023 Nov 15;34(11):2014-2021. doi: 10.1021/acs.bioconjchem.3c00313. Epub 2023 Aug 9.
The neuropeptide-Y (NPY) family acts through four G protein-coupled receptor subtypes in humans, namely, Y, Y, Y, and Y. A growing body of evidence suggest the involvement of the NPY system in several cancers, notably the Y subtype, thus acting as a relevant target for the development of radiopharmaceuticals for imaging or targeted radionuclide therapy (TRT). Here, the [cPP(1-7),NPY(19-23),Ala,Aib,Gln]hPP scaffold, further referred to as sYago, was modified with a DOTA chelator and radiolabeled with Ga and In and investigated and using the MCF-7 model. For studies, MCF-7 cells were orthotopically implanted in female nude mice and imaging with small animal positron emission tomography/computed tomography (μPET/CT) was performed. At the end of imaging, the mice were sacrificed. A scrambled version of sYago, which was also modified with a DOTA chelator, served as a negative control (DOTA-[Nle]sYago_scrambled). sYago and DOTA-sYago showed subnanomolar affinity toward the Y (0.9 ± 0.1 and 0.8 ± 0.1 nM, respectively) and a single binding site at the Y was identified. [Ga]Ga-DOTA-sYago and [In]In-DOTA-sYago were hydrophilic and showed high specific internalization (1.61 ± 0.75%/10 cells at 1 h) and moderate efflux (55% of total binding externalized at 45 min). On μPET/CT images, most of the signal was depicted in the kidneys and the liver. MCF-7 tumors were clearly visualized. On biodistribution studies, [Ga]Ga-DOTA-sYago was eliminated by the kidneys (∼60 %ID/g). The kidney uptake is Y-mediated. A specific uptake was also noted in the liver (5.09 ± 1.15 %ID/g vs 1.13 ± 0.21 %ID/g for [Ga]Ga-DOTA-[Nle]sYago_scrambled, < 0.05), the lungs (1.03 ± 0.34 %ID/g vs 0.20 %ID/g, < 0.05), and the spleen (0.85 ± 0.09%ID/g vs 0.16 ± 0.16%ID/g, < 0.05). In MCF-7 tumors, [Ga]Ga-DOTA-sYago showed 12-fold higher uptake than [Ga]Ga-DOTA-[Nle]sYago_scrambled (3.43 ± 2.32 vs 0.27 ± 0.15 %ID/g, respectively, = 0.0008) at 1 h post-injection. Finally, a proof-of-principle tissular micro-imaging study on a human primary cancer sample showed weak binding of [In]In-DOTA-sYago in prostatic intra-neoplasia and high binding in the ISUP1 lesion while normal prostate was free of signal.
神经肽Y（NPY）家族通过人类的四种G蛋白偶联受体亚型发挥作用，即Y1、Y2、Y4和Y5。越来越多的证据表明NPY系统参与了多种癌症，特别是Y5亚型，因此它成为开发用于成像或靶向放射性核素治疗（TRT）的放射性药物的相关靶点。在此，用DOTA螯合剂修饰了[cPP(1 - 7),NPY(19 - 23),Ala,Aib,Gln]hPP支架（以下简称sYago），并用镓和铟进行放射性标记，并使用MCF - 7模型进行研究。对于体内研究，将MCF - 7细胞原位植入雌性裸鼠体内，并进行小动物正电子发射断层扫描/计算机断层扫描（μPET/CT）成像。成像结束时，处死小鼠。同样用DOTA螯合剂修饰的sYago的乱序版本用作阴性对照（DOTA - [Nle]sYago_scrambled）。sYago和DOTA - sYago对Y5显示出亚纳摩尔亲和力（分别为0.9±0.1和0.8±0.1 nM），并且在Y5上鉴定出一个单一结合位点。[68Ga]Ga - DOTA - sYago和[111In]In - DOTA - sYago具有亲水性，显示出高特异性内化（1小时时为1.61±0.75%/106细胞）和中等程度的外流（45分钟时总结合的55%外化）。在μPET/CT图像上，大部分信号显示在肾脏和肝脏中。MCF - 7肿瘤清晰可见。在生物分布研究中，[68Ga]Ga - DOTA - sYago通过肾脏清除（约60%ID/g）。肾脏摄取是由Y5介导的。在肝脏（[68Ga]Ga - DOTA - sYago为5.09±1.15%ID/g，而[68Ga]Ga - DOTA - [Nle]sYago_scrambled为1.13±0.21%ID/g，P<0.05）、肺（1.03±0.34%ID/g对0.20%ID/g，P<0.05）和脾脏（0.85±0.09%ID/g对0.16±0.16%ID/g，P<0.05）中也观察到特异性摄取。在MCF - 7肿瘤中，注射后1小时，[68Ga]Ga - DOTA - sYago的摄取比[68Ga]Ga - DOTA - [Nle]sYago_scrambled高12倍（分别为3.43±2.32对0.27±0.15%ID/g，P = 0.0008）。最后，一项关于人类原发性癌症样本的原理验证组织显微成像研究表明，[111In]In - DOTA - sYago在前列腺上皮内瘤变中结合较弱，而在ISUP1病变中结合较强，而正常前列腺无信号。
