53BP1 loss elicits cGAS-STING-dependent antitumor immunity in ovarian and pancreatic cancer

Bibliographic Details
Title: 53BP1 loss elicits cGAS-STING-dependent antitumor immunity in ovarian and pancreatic cancer
Authors: Yajie Sun, Jeffrey Patterson-Fortin, Sen Han, Zhe Li, Zuzanna Nowicka, Yuna Hirohashi, Susan Kilgas, Jae Kyo Yi, Alexander Spektor, Wojciech Fendler, Panagiotis A. Konstantinopoulos, Dipanjan Chowdhury
Source: Nature Communications, Vol 15, Iss 1, Pp 1-16 (2024)
Publisher Information: Nature Portfolio, 2024.
Publication Year: 2024
Collection: LCC:Science
Subject Terms: Science
More Details: Abstract 53BP1 nucleates the anti-end resection machinery at DNA double-strand breaks, thereby countering BRCA1 activity. Loss of 53BP1 leads to DNA end processing and homologous recombination in BRCA1-deficient cells. Consequently, BRCA1-mutant tumors, typically sensitive to PARP inhibitors (PARPi), become resistant in the absence of 53BP1. Here, we demonstrate that the ‘leaky’ DNA end resection in the absence of 53BP1 results in increased micronuclei and cytoplasmic double-stranded DNA, leading to activation of the cGAS-STING pathway and pro-inflammatory signaling. This enhances CD8+ T cell infiltration, activates macrophages and natural killer cells, and impedes tumor growth. Loss of 53BP1 correlates with a response to immune checkpoint blockade (ICB) and improved overall survival. Immunohistochemical assessment of 53BP1 in two malignancies, high grade serous ovarian cancer and pancreatic ductal adenocarcinoma, which are refractory to ICBs, reveals that lower 53BP1 levels correlate with an increased adaptive and innate immune response. Finally, BRCA1-deficient tumors that develop resistance to PARPi due to the loss of 53BP1 are susceptible to ICB. Therefore, we conclude that 53BP1 is critical for tumor immunogenicity and underpins the response to ICB. Our results support including 53BP1 expression as an exploratory biomarker in ICB trials for malignancies typically refractory to immunotherapy.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 2041-1723
Relation: https://doaj.org/toc/2041-1723
DOI: 10.1038/s41467-024-50999-2
Access URL: https://doaj.org/article/d04a618cd1684767a7029059b0c86b6d
Accession Number: edsdoj.04a618cd1684767a7029059b0c86b6d
Database: Directory of Open Access Journals
More Details
ISSN:20411723
DOI:10.1038/s41467-024-50999-2
Published in:Nature Communications
Language:English