Our results indicate the following: (i) STING expression is observed in 90% of PDAC cases, and the overall survival of PDAC patients is higher in cGAS and STING double-expressing tumors; (ii) in the tissues with cGAS-STING double-positive, there is a continuous infiltration of cytotoxic CD8 + cells from stromal to cancerous tissues, and they contain more rCAFs; and (iii) in the co-culture system, cGAS-STING signaling facilitates immune cell infiltration and subsequent cancer cell death by maintaining rCAF properties of CAFs. Here, CGAS is linked to cancer.