Oncogenic KRAS-driven type I interferon signalling primes pancreatic cancer for necroptosis.

Pancreatic ductal adenocarcinoma (PDAC) is projected to become the second leading cause of cancer-related death within this decade. Here, we show that its major driver oncogene KRAS activates the cGAS-STING-TBK1 axis, inducing a type I interferon (IFN) response that primes PDAC cells for necroptosis. Using genetically engineered mouse models, we find that cancer cell-specific deletion of caspase-8 is sufficient to trigger necroptotic cell death, eliminating most pancreatic precursor lesions. Mechanistically, KRAS-driven IFN signalling induces ISGF3-dependent expression of necroptosis-related interferon-stimulated genes, including MLKL. This renders PDAC cells selectively vulnerable to necroptosis upon caspase-8 inhibition. Therapeutically, pharmacologic caspase inhibition reduces tumour burden in aggressive PDAC models and human patient-derived organoids. A pan-cancer transcriptomic analysis links necroptosis gene expression with Ras pathway activity and IFN signatures across multiple tumour types. These findings reveal a KRAS-induced IFN program that sensitises tumour cells to necroptosis, highlighting a therapeutic vulnerability in PDAC with broader relevance across IFN-activated cancers.