Residual Lung Cancer After Incomplete Microwave Ablation Exhibits cGAS–STING–ZEB1-Driven Malignant Progression

Background: Incomplete microwave ablation (iMWA) of lung cancer often leads to rapid recurrence and metastasis, yet the underlying mechanisms remain unclear. This study explored whether iMWA promotes tumor progression by activating the cyclic GMP–AMP synthase–stimulator of interferon genes (cGAS–STING) signaling pathway and its downstream effector ZEB1 in tumor cells. Materials and Methods: An in vivo iMWA model was established in nude mice bearing H1650 lung tumors, and an in vitro sublethal heat treatment model was used to mimic incomplete ablation. Transcriptomic profiling, molecular assays and functional analyses assessed cellular behavior and signaling activity changes post-iMWA; genetic and pharmacologic interventions modulated STING signaling and autophagy. Results: Post-iMWA residual cells exhibited enhanced proliferation and invasion. Thermal injury induced necrosis and inhibited mitophagy, causing cytosolic mtDNA accumulation that activated the intrinsic cGAS–STING pathway. This upregulation of ZEB1 drove epithelial–mesenchymal transition and dissemination. Notably, silencing STING or ZEB1, or pharmacologically restoring autophagy, significantly suppressed tumor growth and metastasis. Conclusions: iMWA drives malignant progression of lung cancer through an mtDNA–cGAS–STING–ZEB1 signaling axis. Targeting this pathway—by inhibiting STING or enhancing autophagy—may represent a promising therapeutic strategy to mitigate recurrence and metastasis following microwave ablation.