An AIE-based theranostic nanoplatform for enhanced colorectal cancer therapy: Real-time tumor-tracking and chemical-enhanced photodynamic therapy

Abstract

The combination of diagnostic and therapeutic agents in the form of theranostic platforms to enhance tumor therapeutic efficacy is receiving increasing attention in recent years. However, simultaneous encapsulation, embedding or conjugation of various agents to traditional theranostic nanocarriers always require intricate synthetic process. Herein, a supramolecular drug-drug self-delivery nanosystem (DSDN) based on a newly developed aggregation-induced emission (AIE) photosensitizer (CBTM) and an anti-tumor tyroservaltide (YSV) was constructed for near-infrared (NIR) fluorescence imaging-guided photodynamic/chemotherapy of tumor. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) confirmed that YSV and CBTM could co-assemble into YSV/CBTM nanoparticles, with regular round-shape morphology and homogeneous size. Inspiringly, YSV/CBTM nanoparticles could effectively overcome the aggregation-caused quenching (ACQ) effect, and enter CT26 tumor cells with a high NIR fluorescence emission, allowing preoperative diagnosis. Meanwhile, the as-prepared YSV/CBTM could efficiently generate reactive oxygen species (ROS) under NIR light irradiation, exhibiting photodynamic ablation of tumor cells. More importantly, the peptide drug of YSV not only improved the availability of CBTM nanoparticles, but also served as a toxic adjuvant to enhance the photodynamic therapy (PDT) efficacy of CBTM. In vitro and in vivo assays revealed that most of colorectal tumor cells and tumor tissues were thoroughly ablated by photodynamic-chemotherapy integrated nanoparticles, resulting in longer survival of tumor-bearing mice. Regarding the advantages of the YSV/CBTM nanosystem, we believe this research could offer valuable guidance for the design of nanodrugs with high performance for cancer theranostics.