| First Author | Shen J | Year | 2019 |
| Journal | Cancer Res | Volume | 79 |
| Issue | 2 | Pages | 311-319 |
| PubMed ID | 30482774 | Mgi Jnum | J:352690 |
| Mgi Id | MGI:6274759 | Doi | 10.1158/0008-5472.CAN-18-1003 |
| Citation | Shen J, et al. (2019) PARPi Triggers the STING-Dependent Immune Response and Enhances the Therapeutic Efficacy of Immune Checkpoint Blockade Independent of BRCAness. Cancer Res 79(2):311-319 |
| abstractText | : PARP inhibitors (PARPi) have shown remarkable therapeutic efficacy against BRCA1/2-mutant cancers through a synthetic lethal interaction. PARPi exert their therapeutic effects mainly through the blockade of ssDNA damage repair, which leads to the accumulation of toxic DNA double-strand breaks specifically in cancer cells with DNA repair deficiency (BCRAness), including those harboring BRCA1/2 mutations. Here we show that PARPi-mediated modulation of the immune response contributes to their therapeutic effects independently of BRCA1/2 mutations. PARPi promoted accumulation of cytosolic DNA fragments because of unresolved DNA lesions, which in turn activated the DNA-sensing cGAS-STING pathway and stimulated production of type I IFNs to induce antitumor immunity independent of BRCAness. These effects of PARPi were further enhanced by immune checkpoint blockade. Overall, these results provide a mechanistic rationale for using PARPi as immunomodulatory agents to harness the therapeutic efficacy of immune checkpoint blockade. SIGNIFICANCE: This work uncovers the mechanism behind the clinical efficacy of PARPi in patients with both BRCA-wild-type and BRCA-mutant tumors and provides a rationale for combining PARPi with immunotherapy in patients with cancer. |
