In vivo NIRF imaging-guided delivery of a novel NGR-VEGI fusion protein for targeting tumor vasculature
In vivo NIRF imaging-guided delivery of a novel NGR-VEGI fusion protein for targeting tumor vasculature
复制标题
体内 NIRF 成像引导递送新型 NGR-VEGI 融合蛋白，用于靶向肿瘤血管系统。
DOI：
10.1007/s00726-014-1828-6
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发表时间：
2014-12-01
期刊：
影响因子：
3.5
通讯作者：
Chen, Kai
中科院分区：
文献类型：
--
作者：
Ma, Wenhui;Li, Guoquan;Chen, Kai
病理性血管生成在肿瘤的生长、侵袭和转移中起着至关重要的作用。血管内皮生长抑制因子（VEGI）是肿瘤坏死因子超家族成员之一，是肿瘤血管生成的内源性抑制因子。含有天冬酰胺-甘氨酸-精氨酸（NGR）序列的分子探针可以特异性结合在新生血管和几种肿瘤细胞上过表达的CD 13受体。近红外荧光（NIRF）光学成像靶向肿瘤血管提供了一种非侵入性的方法，用于早期检测肿瘤血管生成和有效监测抗肿瘤血管治疗的反应。本研究的目的是开发一种新的近红外成像探针的基础上NGR-VEGI蛋白的肿瘤血管可视化。原核表达NGR-VEGI融合蛋白，并对其功能进行体外鉴定。然后用Cy5.5荧光团标记NGR-VEGI蛋白以提供Cy5.5-NGR-VEGI探针。使用NIRF成像技术，我们可视化并定量Cy5.5-NGR-VEGI蛋白向小鼠异种移植物中皮下HT-1080纤维肉瘤肿瘤的特异性递送。Cy5.5-NGR-VEGI探针在注射后8小时（pi）表现出快速的HT-1080肿瘤靶向和最高的肿瘤与背景对比度。Cy5.5-NGR-VEGI的肿瘤特异性通过在未标记的NGR-VEGI（20 mg/kg）存在下有效阻断肿瘤摄取来证实。离体NIRF成像进一步证实了体内成像结果，表明Cy5.5-NGR-VEGI在非阻断组中在8 h pi时显示出优异的肿瘤-肌肉比（18.93 +/-A2.88），而阻断组的肿瘤-肌肉比（4.92 +/-A0.75）显著降低。总之，Cy5.5-NGR-VEGI提供了HT-1080肿瘤的高度灵敏、靶特异性和纵向成像。Cy5.5-NGR-VEGI作为一种新的治疗诊断蛋白，具有通过靶向肿瘤血管系统来改善癌症治疗的潜力。
Pathological angiogenesis is crucial in tumor growth, invasion and metastasis. Previous studies demonstrated that the vascular endothelial growth inhibitor (VEGI), a member of the tumor necrosis factor superfamily, can be used as a potent endogenous inhibitor of tumor angiogenesis. Molecular probes containing the asparagine-glycine-arginine (NGR) sequence can specifically bind to CD13 receptor which is overexpressed on neovasculature and several tumor cells. Near-infrared fluorescence (NIRF) optical imaging for targeting tumor vasculature offers a noninvasive method for early detection of tumor angiogenesis and efficient monitoring of response to anti-tumor vasculature therapy. The aim of this study was to develop a new NIRF imaging probe on the basis of an NGR-VEGI protein for the visualization of tumor vasculature. The NGR-VEGI fusion protein was prepared from prokaryotic expression, and its function was characterized in vitro. The NGR-VEGI protein was then labeled with a Cy5.5 fluorophore to afford Cy5.5-NGR-VEGI probe. Using the NIRF imaging technique, we visualized and quantified the specific delivery of Cy5.5-NGR-VEGI protein to subcutaneous HT-1080 fibrosarcoma tumors in mouse xenografts. The Cy5.5-NGR-VEGI probe exhibited rapid HT-1080 tumor targeting, and highest tumor-to-background contrast at 8 h post-injection (pi). Tumor specificity of Cy5.5-NGR-VEGI was confirmed by effective blocking of tumor uptake in the presence of unlabeled NGR-VEGI (20 mg/kg). Ex vivo NIRF imaging further confirmed in vivo imaging findings, demonstrating that Cy5.5-NGR-VEGI displayed an excellent tumor-to-muscle ratio (18.93 +/- A 2.88) at 8 h pi for the non-blocking group and significantly reduced ratio (4.92 +/- A 0.75) for the blocking group. In conclusion, Cy5.5-NGR-VEGI provided highly sensitive, target-specific, and longitudinal imaging of HT-1080 tumors. As a novel theranostic protein, Cy5.5-NGR-VEGI has the potential to improve cancer treatment by targeting tumor vasculature.