Targeting RRM2 with dual-modal theranostic smart nanoresponder overcomes osimertinib resistance and triggers immune remodeling in NSCLC

Osimertinib (Osi) resistance limits its efficacy in EGFR-mutant non-small cell lung cancer (NSCLC). Here, we developed a pH-responsive cationic nanovesicle (¹²⁴I/Cy5.5-sO@FCLs), equipped with dual-modal positron emission tomography (PET) and fluorescence imaging capabilities, to enable dynamic monitoring of the role of ribonucleotide reductase M2 subunit (RRM2) disruption in overcoming Osi resistance and enhance targeted anticancer efficacy in NSCLC. RRM2 was identified as a critical driver of poor prognosis and Osi resistance in NSCLC. The ¹²⁴I/Cy5.5-sO@FCLs enabled real-time tracking of tumor targeting and biodistribution, and CRISPR-Cas9-mediated RRM2 disruption efficiently reversed Osi resistance and potentiated synergistic anticancer effects, which was attributed to counteracting TGF-β/Smad2/3-mediated epithelial-mesenchymal transition (EMT) and amplifying cGAS/STING-induced ferroptosis. Furthermore, the nanovesicles triggered STING-dependent immunogenic cell death (ICD), stimulating tumor infiltration of dendritic cells (DCs) and T cells; combination with anti-PD-L1 therapy augmented NSCLC regression. Collectively, ¹²⁴I/Cy5.5-sO@FCLs integrate gene editing with targeted therapies while enabling dynamic, quantitative monitoring, providing an approach for precision-targeted treatment in Osi-resistant NSCLC.