Dong Lili, Zhou Hongxin, Zhao Menglong, Gao Xinghui, Liu Yang, Liu Dongli, Guo Wei, Hu Hongwei, Xie Qian, Fan Jia, Lin Jiang, Wu Weizhong
Liver Cancer Institute, Zhongshan Hospital, Fudan University, Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Shanghai 200032, China.
Department of Radiology and Shanghai Institute of Medical Imaging, Zhongshan Hospital, Fudan University, Shanghai 200032, China.
Mol Ther Nucleic Acids. 2018 Dec 7;13:376-386. doi: 10.1016/j.omtn.2018.09.013. Epub 2018 Sep 27.
Glypican-3 (GPC3), the cellular membrane proteoglycan, has been established as a tumor biomarker for early diagnosis of hepatocellular carcinoma (HCC). GPC3 is highly expressed in more than 70% HCC tissues detected by antibody-based histopathological systems. Recently, aptamers, a short single-strand DNA or RNA generated from systematic evolution of ligands by exponential enrichment (SELEX), were reported as potential alternatives in tumor-targeted imaging and diagnosis. In this study, a total of 19 GPC3-bound aptamers were successfully screened by capillary electrophoresis (CE)-SELEX technology. After truncated, AP613-1 was confirmed to specifically target GPC3 with a dissociation constant (K) of 59.85 nM. When modified with a phosphorothioate linkage, APS613-1 targeted GPC3 with a K of 15.48 nM and could be used as a specific probe in living Huh7 and PLC/PRF/5 imaging, GPC3-positive cell lines, but not in L02 or A549, two GPC3-negative cell lines. More importantly, Alexa Fluor 750-conjugated APS613-1 could be used as a fluorescent probe to subcutaneous HCC imaging in xenograft nude mice. Our results indicated that modified AP613-1, especially APS613-1, was a potential agent in GPC3-positive tumor imaging for HCC early diagnosis.
磷脂酰肌醇蛋白聚糖-3（GPC3）是一种细胞膜蛋白聚糖，已被确立为肝细胞癌（HCC）早期诊断的肿瘤生物标志物。基于抗体的组织病理学系统检测发现，超过70%的HCC组织中GPC3高表达。最近，适体作为一种通过指数富集的配体系统进化（SELEX）产生的短单链DNA或RNA，被报道为肿瘤靶向成像和诊断的潜在替代物。在本研究中，通过毛细管电泳（CE）-SELEX技术成功筛选出总共19种与GPC3结合的适体。经过截短后，AP613-1被证实能特异性靶向GPC3，解离常数（K）为59.85 nM。当用硫代磷酸酯键修饰后，APS613-1以15.48 nM的K值靶向GPC3，可作为活的Huh7和PLC/PRF/5成像（GPC3阳性细胞系）的特异性探针，但不能用于L02或A549这两种GPC3阴性细胞系。更重要的是，Alexa Fluor 750偶联的APS613-1可作为荧光探针用于异种移植裸鼠皮下HCC成像。我们的结果表明，修饰后的AP613-1，尤其是APS613-1，是用于HCC早期诊断的GPC3阳性肿瘤成像的潜在试剂。
