A CD44-targeted PDA/ZnO redox-active nanocomposite that couples chemotherapy with mitochondrial stress and tumor immune remodeling

Bladder cancer therapy is frequently limited by inefficient drug retention and adaptive immune resistance within a hypoxic tumor microenvironment. Here, we report a CD44-targeted, fully synthetic nanocomposite (HPPZC) that converts chemotherapy into a mitochondria-associated therapeutic strategy accompanied by tumor immune remodeling. Rapid microwave-assisted assembly integrates hyaluronic acid (HA), polydopamine (PDA), protamine, zinc oxide (ZnO), and camptothecin (CPT) into a structurally integrated hybrid nanocomposite with tumor targeting, while the PDA/ZnO interface functions as a redox-active platform associated with mitochondrial dysfunction and redox modulation. HPPZC induces rapid mitochondrial depolarization, elevates oxidative stress, and is associated with PINK1/Parkin-related mitochondrial quality-control and autophagy-associated turnover signatures. In vivo, HPPZC treatment prolonged local intratumoral retention and produced tumor regression. The combination of chemotherapy with mitochondrial stress and tumor immune remodeling, suppressing CXCL12 and PD-L1, promoting M1-like marker profile, and increasing CD8⁺ T-cell infiltration. This work establishes a reproducibly fabricated redox-active nanotherapeutic associated with mitochondrial stress that couples targeted chemotherapy with immune microenvironment remodeling for antitumor efficacy.