Self-Delivery Nanotherapeutics for Tumor Low-Temperature Photothermal Immunotherapy through Cascade Heat Shock Protein and Inflammation Inhibition
Xiaoliang Deng, Xianquan Feng, Xiaohui Tang, Zhihui Zheng, Da Zheng, Enqin Zheng, Lingjun Zeng, Shiying Xu, Boxin Chen, Qian Zhang, Zhihong Liu, Hongtao Song
Abstract
The clinical efficacy of immunotherapy in triple-negative breast cancer (TNBC) faces dual barriers: poor immunogenicity and a suppressive tumor microenvironment. While low-temperature photothermal therapy (LTPTT) has emerged as a potential immunostimulatory strategy, its efficacy is counteracted by heat shock protein (HSP) induction and COX-2/PGE2-mediated immunosuppression. To address these challenges, we developed a multifunctional immunophotothermal nanoplatform (IAC NPs) through rational engineering of human serum albumin for combinatorial delivery of indocyanine green as a photothermal converter, atovaquone for HSP70-mediated thermoresistance blockade, and celecoxib for COX-2/PGE2 pathway inhibition. The IAC NPs achieved tumor-targeted delivery and NIR-activated immunogenic phototherapy while coinhibiting HSP70 (via atovaquone's mitochondrial complex III blockade) and the COX-2/PGE2 immunosuppressive axis (via celecoxib). The triple medications' synergistic action improved the expression of effector memory T cells, boosted the maturation of dendritic cells, encouraged the infiltration of CD4+ and CD8+ T cells, and reduced regulatory T cells. In vivo, the IAC NPs mediated profound suppression of both primary tumors and metastatic dissemination while exhibiting optimal biocompatibility for clinical translation. Our work validates a nanoenabled self-delivery system that augments the efficacy of LTPTT immunotherapy against TNBC by orchestrating coordinated inhibition of HSPs and inflammatory responses.