Aminopeptidase N (CD13) as the malignant cell surface marker is overexpressed on many tumor cells including lung cancer and the neovascular cell membranes. A tripeptide structure, Asn-Gly-Arg (NGR), can specifically bind to CD13. In this study, we successfully labeled various NGR peptides derivatives with FITC or 177Lu at high efficiency. The 177Lu labeling of the NGR peptides was stable in vitro. The cellular uptake of the 177Lu-labeled cyclic NGR peptides was different by varying the structure of peptides.

中文翻译：

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177Lu/FITC 标记的 NGR 肽的制备和细胞相互作用研究

氨肽酶 N (CD13) 作为恶性细胞表面标志物在许多肿瘤细胞上过表达，包括肺癌和新生血管细胞膜。三肽结构 Asn-Gly-Arg (NGR) 可以与 CD13 特异性结合。在这项研究中，我们成功地用 FITC 或 177Lu 高效标记了各种 NGR 肽衍生物。NGR 肽的 177Lu 标记在体外是稳定的。通过改变肽的结构，177Lu 标记的环状 NGR 肽的细胞摄取是不同的。