Berberine/Verteporfin Nanomicelles Enable O2-Economized Photodynamic Immunotherapy in Esophageal Cancer Via Tumor Metabolic Remodeling

Photodynamic therapy (PDT) can convert oxidative damage into systemic antitumor immunity, but mitochondrial oxygen consumption, lactate accumulation, and aberrant angiogenesis create a hypoxic and immunosuppressive tumor microenvironment that limits treatment. Here, berberine (BBR) and verteporfin (VER) were co-loaded into nanomicelles (BV NMs) through sonication-assisted self-assembly of PEG-g-(PVAc-co-PVCL), creating a “microenvironment remodeling—PDT potentiation—immune activation” strategy. BV NMs had a hydrodynamic diameter of 56.15 ± 0.30 nm. Drug loading lowered the critical micelle concentration from 11.2 μg/mL (blank micelles) to an apparent 1.3 μg/mL (BV NMs), supporting dilution stability. It also enhanced aqueous dispersibility, cellular uptake, and intratumoral accumulation. Mechanistically, BBR reduced mitochondrial complex I-associated activity, intracellular adenosine triphosphate levels, and extracellular lactate accumulation, attenuated cellular hypoxia and hypoxia-inducible factor-1α responses, and increased intracellular oxygen availability. Before irradiation, VER suppressed Yes-associated protein signaling and vascular endothelial growth factor expression, providing light-independent antitumor and antiangiogenic regulation. Under 660 nm irradiation, VER induced reactive oxygen species accumulation, mitochondrial depolarization, tumor-cell death, and immunogenic cell death. In vivo, BV NMs combined with irradiation achieved an approximately 96% inhibition rate based on terminal tumor weight. Proportions of mature dendritic cells in tumor-draining lymph nodes and splenic CD8+ T cells reached 3.33 and 2.73 times the control levels, respectively, alongside expansion of memory CD8+ T-cell populations. Treatment also reduced experimental pulmonary metastatic burden, achieved 50% survival at day 60, and caused no evident short-term systemic toxicity. This platform couples metabolic and angiogenic regulation with oxygen-dependent PDT and antitumor immunity, providing a strategy against primary and metastatic tumors.