Medical College of Xiamen University, Xiamen University, Xiamen, China.
Department of Nuclear Medicine & Minnan PET Center, Xiamen Cancer Hospital, The First Affiliated Hospital of Xiamen University, Teaching Hospital of Fujian Medical University, Xiamen, China.
Anticancer Agents Med Chem. 2020;20(13):1548-1557. doi: 10.2174/1871520620666200424101936.
Tumor Necrosis Factor Receptor 1 (TNFR1) and integrin αvβ3 receptor are overexpressed in breast cancer. We hypothesized that a peptide ligand recognizing both receptors in a single receptor-binding probe would be advantageous. Here, we developed a novel 18F-labeled fusion peptide probe [18F]-NOTA-Gly3- E(2PEG4-RGD-WH701) targeting dual receptors (TNFR1 and αvβ3) and evaluated the diagnostic efficacy of this radioactive probe in both MDA-MB-231 and MCF-7 xenograft models in mice.
The NOTA-conjugated RGD-WH701 analog was radiolabeled with 18F using NOTA-AlF chelation method. We used two PEG4 molecules and Glutamic acid (Glu) to covalently link c(RGDyK) with WH701. Gly3 was also added to further improve the water solubility and pharmacokinetic properties of the probe. The expression of TNFR1 and Integrin αvβ3 in MCF-7 and MDA-MB-231 cells was detected by western blot analysis and immunofluorescence staining. The tumor-targeting characteristics of [18F]-NOTA-Gly3-E(2PEG4-RGDWH701) were assessed in nude mice bearing MDA-MB-231 and MCF-7 xenografts.
HPLC analysis of the product NOTA-G3-E (2P4-RGD-WH701) revealed a purity >95%. The yield after attenuation correction was approximately 33.5%±2.8% (n=5), and the radiochemical purity was above 95%. The MDA-MB-231 tumor uptake of [18F]-NOTA-Gly3-E(2PEG4-RGD-WH701) was 1.14±0.14%ID/g, as measured by PET at 40min postinjection (p.i.). In comparison, the tumor uptake of [18F]-NOTA-RGD and [18F]- NOTA-WH701 in MDA-MB-231 xenografts was 0.96±0.13%ID/g and 0.93±0.28%ID/g, respectively. The MCF-7 tumor uptake of [18F]-NOTA-Gly3-E(2PEG4-RGD-WH701) was 1.22±0.11%ID/g, as measured by PET at 40min postinjection (p.i.). In comparison, the tumor uptake of [18F]-NOTA-RGD and [18F]-NOTA-WH701 in MCF-7 xenografts was 0.99±0.18%ID/g and 0.57±0.08%ID/g, respectively.
[18F]AlF-NOTA-Gly3-E(2PEG4-RGD-WH701) was successfully synthesized and labeled with 18F. The results from the microPET/CT and biodistribution studies of [18F]AlF-NOTA-Gly3-E(2PEG4-RGDWH701) showed that the tracer could specifically target TNFR1 and integrin αvβ3 receptors.
肿瘤坏死因子受体 1（TNFR1）和整合素αvβ3 受体在乳腺癌中过度表达。我们假设在单个受体结合探针中识别这两个受体的肽配体将是有利的。在这里，我们开发了一种新型的 18F 标记融合肽探针[18F]-NOTA-Gly3-E（2PEG4-RGD-WH701），靶向双重受体（TNFR1 和αvβ3），并在 MDA-MB-231 和 MCF-7 异种移植模型小鼠中评估了这种放射性探针的诊断效果。
NOTA 缀合的 RGD-WH701 类似物使用 NOTA-AlF 螯合方法用 18F 标记。我们使用两个 PEG4 分子和谷氨酸（Glu）将 c（RGDyK）与 WH701 共价连接。还添加了 Gly3 以进一步提高探针的水溶性和药代动力学特性。通过 Western blot 分析和免疫荧光染色检测 MCF-7 和 MDA-MB-231 细胞中 TNFR1 和整合素αvβ3 的表达。评估 [18F]-NOTA-Gly3-E（2PEG4-RGD-WH701）在携带 MDA-MB-231 和 MCF-7 异种移植物的裸鼠中的肿瘤靶向特性。
产品 NOTA-G3-E（2P4-RGD-WH701）的 HPLC 分析显示纯度>95%。衰减校正后的产率约为 33.5%±2.8%（n=5），放射化学纯度>95%。[18F]-NOTA-Gly3-E（2PEG4-RGD-WH701）在 MDA-MB-231 肿瘤中的摄取率为 1.14±0.14%ID/g，在 40min 注射后（p.i.）通过 PET 测量。相比之下，[18F]-NOTA-RGD 和 [18F]-NOTA-WH701 在 MDA-MB-231 异种移植瘤中的摄取率分别为 0.96±0.13%ID/g 和 0.93±0.28%ID/g。[18F]-NOTA-Gly3-E（2PEG4-RGD-WH701）在 MCF-7 肿瘤中的摄取率为 1.22±0.11%ID/g，在 40min 注射后（p.i.）通过 PET 测量。相比之下，[18F]-NOTA-RGD 和 [18F]-NOTA-WH701 在 MCF-7 异种移植瘤中的摄取率分别为 0.99±0.18%ID/g 和 0.57±0.08%ID/g。
[18F]AlF-NOTA-Gly3-E（2PEG4-RGD-WH701）成功合成并标记了 18F。[18F]AlF-NOTA-Gly3-E（2PEG4-RGD-WH701）的 microPET/CT 和生物分布研究结果表明，示踪剂可以特异性靶向 TNFR1 和整合素αvβ3 受体。
