Abstract

Amplifying intracellular oxidative stress by organelle-targeted reactive oxygen species (ROS) production combined with tumor cell-specific gene disruption is a promising strategy for tumor treatment. However, due to the vulnerability of CRISPR/Cas9 ribonucleoproteins (RNPs) to ROS, co-delivery of CRISPR/Cas9 RNPs and ROS generators to enhance the sensitivity of tumor cells to oxidative stress remains challenging. Herein, a cascade-responsive “oxidative stress amplifier” (named DR-TAF-pHT/FA) is proposed, which can successively respond to cathepsin B, localized laser irradiation and ATP to generate ROS on the lysosomal membrane of tumor cells and release Cas9/sg Nrf2 RNPs for efficient gene disruption. It is demonstrated that, under near infrared (NIR) irradiation, DR-TAF-pHT/FA achieves targeted rupture of lysosomal membranes, inducing significant intracellular oxidative stress. Meanwhile, due to the protective function of TAF coating (TA-Fe 3+ coordination self-assembled networks), Cas9/sg Nrf2 RNPs can safely escape into the cytoplasm and be released in response to ATP, further amplifying oxidative stress and promoting tumor cell apoptosis through efficient Nrf2 gene disruption. Treatment with DR-TAF-pHT/FA + NIR significantly improves tumor ablation efficiency and extends median survival time (over 70 days) in Hela xenograft models. This “oxidative stress amplifier” provides a new paradigm for multimodal and synergistic tumor therapy through precise lysosomal membrane bursting together with efficient Nrf2 gene disruption.