Targeted drug delivery using epidermal growth factor peptide-targeted gold nanoparticles (EGFpep-Au NPs) is investigated as a novel approach for delivery of photodynamic therapy (PDT) agents, specifically Pc 4, to cancer. In vitro studies of PDT show that EGFpep-Au NP-Pc 4 is twofold better at killing tumor cells than free Pc 4 after increasing localization in early endosomes. In vivo studies show that targeting with EGFpep-Au NP-Pc 4 improves accumulation of fluorescence of Pc 4 in subcutaneous tumors by greater than threefold compared with untargeted Au NPs. Targeted drug delivery and treatment success can be imaged via the intrinsic fluorescence of the PDT drug Pc 4. Using Pc 4 fluorescence, it is demonstrated in vivo that EGFpep-Au NP-Pc 4 impacts biodistribution of the NPs by decreasing the initial uptake by the reticuloendothelial system (RES) and by increasing the amount of Au NPs circulating in the blood 4 h after IV injection. Interestingly, in vivo PDT with EGFpep-Au NP-Pc 4 results in interrupted tumor growth when compared with EGFpep-Au NP control mice when selectively activated with light. These data demonstrate that EGFpep-Au NP-Pc 4 utilizes cancer-specific biomarkers to improve drug delivery and therapeutic efficacy over untargeted drug delivery.

中文翻译：

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肽靶向金纳米粒子用于脑癌的光动力治疗

使用表皮生长因子肽靶向金纳米粒子 (EGFpep-Au NPs) 进行靶向药物递送作为一种将光动力治疗 (PDT) 药物（特别是 Pc 4）递送至癌症的新方法进行了研究。PDT 的体外研究表明，在增加早期内体定位后，EGFpep-Au NP-Pc 4 在杀死肿瘤细胞方面比游离 Pc 4 好两倍。体内研究表明，与未靶向的 Au NP 相比，EGFpep-Au NP-Pc 4 的靶向可将 Pc 4 在皮下肿瘤中的荧光积累提高三倍以上。靶向药物递送和治疗成功可以通过 PDT 药物 Pc 4 的固有荧光成像。使用 Pc 4 荧光，在体内证明，EGFpep-Au NP-Pc 4 通过减少网状内皮系统 (RES) 的初始摄取和增加静脉注射后 4 小时在血液中循环的 Au NPs 的量来影响 NPs 的生物分布。有趣的是，与 EGFpep-Au NP 对照小鼠相比，当用光选择性激活时，使用 EGFpep-Au NP-Pc 4 的体内 PDT 导致肿瘤生长中断。这些数据表明，EGFpep-Au NP-Pc 4 利用癌症特异性生物标志物来改善药物递送和治疗效果，而不是非靶向药物递送。