STING1 and neoplasm: Activation of the cGAS/STING pathway by PARPi-induced accumulation of double-stranded DNA fragments in the cytosol of tumour cells initiates a type I interferon-like response with the release of the T cell-recruiting chemokines CCL5 and CXCL10, but also the upregulation of PD-L1 [10–12].