Multifunctional Self-Assembly with NIR Light-Activated Cascade Effect for Improving Local Treatment on Solid Tumors

Incomplete local treatment of solid tumors is the main cause of tumor difficult to cure, and easily leads to tumor metastasis and recurrence. The dense external matrix and hypoxic microenvironment of solid tumors severely restrict the therapy efficacy of local tumors. Enhancing the infiltration ability of agents to tumor tissues and adapting the therapy mode favored to hypoxic microenvironments are beneficial to improve the cure rate of tumors. In this work, we designed and developed a self-assembled biomaterial with a cascade effect triggered by near-infrared light. The self-assembly was combined of biotin, phase change material (PNIPAM), photochemical agent (ATT-2), and alkyl radical generator (AIPH). In the assembly, biotin acted as a targeted group. ATT-2 was used to provide heat to synergistically induce the phase change and decompose alkyl radicals. The superficial and deep tumors were ablated by heat and alkyl radicals with white light irradiation of the assembly, respectively. The assay in vivo showed that the self-assembly could effectively eliminate local lesions of solid tumors. This work provides new insights for improving the cure rate of tumors, which not only develops biomaterials adapted to the tumor microenvironment, but also proposes new therapies for complete elimination of solid tumors.