Light-assisted gadofullerene nanoparticles disrupt tumor vasculatures for potent melanoma treatment

The traditional photodynamic therapy (PDT) using a photosensitizer and oxygen under light generates reactive oxygen species (ROS) to kill tumor cells. However, its treatment efficiency is limited by insufficient oxygen in tumor cells. Herein, β-alanine modified gadofullerene nanoparticles (GFNPs) were explored to disrupt tumor vasculatures assisted by light for potent melanoma treatment. As tumor vasculatures are oxygen-rich, the yields of photo-induced singlet oxygen (1O2) by GFNPs are not subjected to the hypoxemia of tumor tissues. Different from the small molecule photosensitizer Chlorin e6 (Ce6), GFNPs realize high-efficiency tumor vascular disruption under light observed by using the mice tumor vascular dorsal skin fold chamber (DSFC) model. The tumor vascular disruption efficiency of GFNPs is size-dependent, and the smallest one (hydration diameter of ca. 126 nm) is more efficient. Mechanistically, the high yields of photo-induced 1O2 by GFNPs can lead to the destruction of the tumor vascular endothelial adherent junction protein-VE cadherin and the decrease of tumor vascular endothelial cells-CD31 proteins, inducing rapid tumor necrosis. In conclusion, our work provides an insight into the design of well-sized nanoparticles to powerfully treat melanoma assisted by light, as well as greatly extending the applications of PDT for robust tumor therapy.