Programmable Tumor‐Activated NanoCRISPR Platform Synergizes cGAS‐STING Activation With PD‐L1 Blockade for Potentiated Antitumor Immunity

ABSTRACT The cGAS‐STING pathway is an essential element of antitumor immunity. However, its activation triggers immunosuppressive molecules like PD‐L1 to feedback upregulate, which limits therapeutic efficacy. Herein, we develop a programmable tumor‐activated nanoCRISPR platform (PATROL) that co‐delivers CRISPR/Cas13a‐CARM1 plasmid and PD‐L1 blocking peptide to stimulate the cGAS‐STING‐IFN‐I pathway and diminish its immunosuppressive feedback loop, thereby improving antitumor efficacy. PATROL achieves enhanced circulation longevity, tumor‐targeting specificity, and tissue penetration due to surface modifications such as PEGylation, hyaluronic acid, and TAT peptide. At the same time, its PD‐L1 blocking peptide on the surface facilitates drug accumulation with the tumor and inhibits PD‐L1 activity. Following exposure to tumor‐associated hyaluronidase, PATROL undergoes enzyme‐triggered disassembly, surface charge reversal, rapid lysosomal escape, and significant CARM1 knockdown, leading to enhanced cGAS‐STING signaling. This bifunctional approach cooperatively reprograms the immunosuppressive tumor microenvironment, increases cytotoxic T lymphocyte infiltration, and elicits powerful antitumor immunity by simultaneously blocking PD‐1/PD‐L1 signaling and activating the cGAS‐STING‐IFN‐I pathway. PATROL exhibits significant antitumor efficacy in B16‐F10 melanoma models, successfully inhibiting tumor growth and prolonging survival. As consequently, PATROL presents an innovative therapeutic strategy that achieves effective tumor suppression by enhancing antitumor immunity through dual‐pathway activation.