Biological Evaluation of a Novel Doxorubicin-Peptide Conjugate for Targeted Delivery to EGF Receptor-Overexpressing Tumor Cells
Biological Evaluation of a Novel Doxorubicin-Peptide Conjugate for Targeted Delivery to EGF Receptor-Overexpressing Tumor Cells
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用于靶向递送至 EGF 受体过表达肿瘤细胞的新型阿霉素-肽缀合物的生物学评价
DOI：
10.1021/mp100243j
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发表时间：
2011-03-01
影响因子：
4.9
通讯作者：
Huang, Zebo
中科院分区：
文献类型：
--
作者：
Ai, Shibin;Duan, Jianli;Huang, Zebo
表皮生长因子受体（EGFR）在多种上皮恶性肿瘤中过表达，因此可用于EGFR靶向治疗以提高抗肿瘤疗效。因此，我们合成了一种新的缀合物阿霉素（DOX）与EGFR结合肽（NH 2-CMYIEALDKYAC-COOH; EBP）通过酯键在14位的DOX通过戊二酸间隔。为了证实DOX-EBP缀合物能够靶向过表达EGFR的肿瘤细胞，我们比较了DOX-EBP和游离DOX的细胞积累、细胞内分布和体外细胞毒性。用等摩尔浓度的DOX-EBP或游离DOX处理后，缀合物在EGFR过表达细胞中的积累水平显著高于在非EGFR过表达细胞中的积累水平，而游离DOX的细胞内积累在所有细胞中几乎相同。然而，DOX-EBP的细胞内积累显着减少EGFR过表达细胞与抑制性抗EGFR单克隆抗体预孵育，证明EGFR途径参与运输的共轭物。共聚焦荧光显微镜显示，共轭物分布在细胞质和核周区域在第一个30分钟，而游离的DOX积累在细胞质和细胞核。然而，24小时后，用DOX-EBP处理的细胞中的DOX信号也分布在细胞核中，表明DOX从缀合物释放并进入细胞核。生物分布和体内抗肿瘤实验以及体外细胞毒性表明DOX-EBP的治疗能力是由于其在EGFR表达肿瘤细胞中的积累增加。此外，用DOX-EBP治疗的荷瘤小鼠的存活率显著高于用游离DOX治疗的荷瘤小鼠。这些数据证明了具有靶向EGFR过表达肿瘤细胞的能力的DOX-EBP缀合物的增强的抗癌功效和降低的全身毒性。
Epidermal growth factor receptor (EGFR) is overexpressed in a variety of epithelial malignancies and thus can be used for EGFR-targeted therapy to improve antitumor efficacy. Therefore we synthesized a novel conjugate of doxorubicin (DOX) with an EGFR-binding peptide (NH2-CMYIEALDKYAC-COOH; EBP) via an ester bond at position 14 of DOX through a glutarate spacer. To confirm that the DOX-EBP conjugate is capable of targeting tumor cells overexpressing EGFR, we compared the cellular accumulation, intracellular distribution and in vitro cytotoxicity of DOX-EBP and free DOX. After treating with equimolar concentration of DOX-EBP or free DOX, the conjugate accumulated at significantly higher levels in EGFR-overexpressing cells than in non-EGFR-overexpressing cells, while the intracellular accumulation of free DOX was almost the same in all the cells. However, the intracellular accumulation of DOX-EBP was significantly reduced in EGFR-overexpressing cells preincubated with inhibitory anti-EGFR monoclonal antibody, demonstrating the involvement of EGFR pathway in the transport of the conjugate. Confocal fluorescence microscopy reveals that the conjugate was distributed in cytoplasmic and perinuclear areas during the first 30 min, whereas the free DOX was accumulated in both cytoplasm and nuclei. After 24 h, however, the DOX signal in the cells treated with DOX-EBP was also distributed in the nuclei, suggesting the release of DOX from the conjugate and entry into the nuclei, Biodistribution and in vivo antitumor experiments, together with in vitro cytotoxicity, indicate that the therapeutic competence of DOX-EBP was due to its increased accumulation in EGFR-expressing tumor cells. Furthermore, the survival of tumor-bearing mice treated with DOX-EBP was significantly higher than that with free DOX. These data demonstrate the enhanced anticancer efficacy and reduced systemic toxicity of DOX-EBP conjugate with targeting ability to EGFR-overexpressing tumor cells.