TPE-Based Peptide Micelles for Targeted Tumor Therapy and Apoptosis Monitoring
Wenjun Qin, Yu Wu, Yunhong Hu, Yanming Dong, Tonghui Hao, Cheng Zhang
Abstract
A targeted drug delivery system with lessened side effects and real-time monitoring of tumor cell apoptosis is highly desirable for precision therapy. Herein, we developed a traceable self-assembled micelle (TPR@DOX) by grafting Arg-Gly-Asp (RGD) peptide and tetraphenylethene (TPE) fluorophore on both axial positions of amphiphilic polymers. The aggregation-induced emission (AIE) characteristics of TPE makes the micelle visible for high-quality imaging, indicating the loading and release of doxorubicin (DOX) during the delivery process. RGD peptide can specifically bind to αvβ3 integrin on tumor cell surfaces to facilitate cellular uptake. Furthermore, TPE fluorophore was linked by a caspase-responsive Asp-Glu-Val-Asp (DEVD) peptide, which could be cleaved and generated a hydrophobic TPE residue, resulting in aggregation and fluorescence recovery to indicate apoptosis. In vitro experiments, such as smart nanoplatform, showed remarkable tumor cell killing ability, opening an avenue in precise tumor therapy.