A novel NAD(P)H:quinone oxidoreductase 1-responsive vascular endothelial growth factor-targeted antibody-drug conjugate induces dual apoptosis and ferroptosis in glioblastoma.

Glioblastoma is a highly malignant and refractory brain tumor with limited treatment options and poor prognosis. Although antibody-drug conjugate (ADC) have shown potential in glioblastoma therapy, their clinical utility is hampered by off-target toxicity. This study aimed to develop a novel NAD(P)H:quinone oxidoreductase 1 (NQO1)-responsive ADC, NRBM-25, to enhance targeting specificity and safety, and to investigate its antitumor mechanisms. NRBM-25 was constructed using an NQO1-enzyme-responsive linker to conjugate a vascular endothelial growth factor-targeting antibody with the cytotoxic payload monomethyl auristatin E, enabling tumor-specific activation. The NQO1-dependent activation mechanism was validated in isogenic and native cell models. In vitro and in vivo, NRBM-25 exhibited potent and selective cytotoxicity against NQO1-high glioblastoma cells while sparing NQO1-low normal cells. The conjugate induced dual modes of cell death-apoptosis and ferroptosis-accompanied by mitochondrial dysfunction, oxidative stress, and cell cycle arrest. In animal models, NRBM-25 significantly inhibited tumor growth, prolonged survival with minimal systemic toxicity, and outperformed temozolomide at medium-to-high doses. This approach of using an enzyme-dependent linker to dually induce apoptosis and ferroptosis offers a potential strategy to overcome treatment resistance, representing a new exploration in ADC-based therapy for glioblastoma. SIGNIFICANCE STATEMENT: A novel antibody-drug conjugate targeting glioblastoma was developed, which uses a tumor-specific enzyme activation mechanism and demonstrates favorable safety and antitumor efficacy in preclinical models. This candidate represents a new exploration in antibody-drug conjugate-based therapy for glioblastoma.