A multifunctional theranostic platform based on peptide modified dendrimer for image-guided combination phototherapy

Inhalt:
Theranostics, where both diagnosis and therapy are simultaneously realized, has become a newly emerging field in recent years, and can be used as an individualized approach to tumor patients. Combination of photothermal (PTT) and photodynamic therapy (PDT) offers unique advantages over PDT or PTT alone. The addition of imaging abilities to such a combinatorial modality also allows the identification of microscopic cancer tumors for a more precise and highly efficient treatment. However, to achieve synergistic PDT/PTT effects, one generally needs two lasers with different wavelengths. Therefore, a single agent-based theranostic nanoplatform was developed for concurrent NIR fluorescence imaging and combinatorial phototherapy with dual PDT and PTT therapeutic mechanisms. In this study, a tumor targeting peptide c(cGRDSPC)K was covalently binding with NIR dye cypate and then conjugate to the PAMAM G5 to improve the accuracy of tumor treatment and enhance antitumor efficiency. The results showed that that c(cGRDSPC)K-modified dendrimer could enhance the tumor targeting properties, as well as be capable to generate ROS and performing high temperature response for PTT on cancer cells under NIR irradiation. In vitro antitumor studies demonstrate that, compared with PDT treatment alone, the combined treatment with the local exposure of NIR light exhibited significantly enhanced anti-tumor efficiency. This multifunctional nanoplatform will provide a new way for the diagnosis and treatment of tumors.