Light‐Triggered Retention and Cascaded Therapy of Albumin‐Based Theranostic Nanomedicines to Alleviate Tumor Adaptive Treatment Tolerance

Abstract Tumor adaptive treatment tolerance associated with chemotherapy originates from low tumor accumulation and adverse effects and remains a formidable challenge for cancer therapy. Herein, human serum albumin (HSA)‐based nanomedicines modified with diazirine and loaded with indocyanine green (ICG) and tirapazamine (TPZ), denoted as ICG/TPZ@HSA dNMs are developed. The obtained ICG/TPZ@HSA dNMs can efficiently eradicate the tumors through a cascade of synergistic events triggered by the sequential irradiation of lasers in the tumor area. Upon a 405 nm laser irradiation, the ICG/TPZ@HSA dNMs are able to form aggregates via crosslinking and thus realized enhanced tumor site accumulation and prolonged retention time. The following irradiation at tumor area with an 808 nm laser‐generated local hyperthermia and reactive oxygen species, which results in efficient tumor ablation and increased local hypoxia in the tumor microenvironment. The resulted local hypoxia further activates the initially nontoxic TPZ to a highly cytotoxic derivative, by which precisely bioactivated chemotherapy is achieved following the phototherapy. Thus, upon the laser irradiations, a cascade of aggregation, phototherapy, and bioactivated chemotherapy is successfully triggered, which achieves efficient precise eradication of tumors without detectable side effects in vivo.