1. Kinase-dead ATM protein is highly oncogenic and can be preferentially targeted by Topo-isomerase I inhibitors
- Author
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Kenta Yamamoto, Jiguang Wang, Lisa Sprinzen, Jun Xu, Christopher J Haddock, Chen Li, Brian J Lee, Denis G Loredan, Wenxia Jiang, Alessandro Vindigni, Dong Wang, Raul Rabadan, and Shan Zha
- Subjects
ATM ,missense mutation ,replication fork ,Topo-isomerase I ,Medicine ,Science ,Biology (General) ,QH301-705.5 - Abstract
Missense mutations in ATM kinase, a master regulator of DNA damage responses, are found in many cancers, but their impact on ATM function and implications for cancer therapy are largely unknown. Here we report that 72% of cancer-associated ATM mutations are missense mutations that are enriched around the kinase domain. Expression of kinase-dead ATM (AtmKD/-) is more oncogenic than loss of ATM (Atm-/-) in mouse models, leading to earlier and more frequent lymphomas with Pten deletions. Kinase-dead ATM protein (Atm-KD), but not loss of ATM (Atm-null), prevents replication-dependent removal of Topo-isomerase I-DNA adducts at the step of strand cleavage, leading to severe genomic instability and hypersensitivity to Topo-isomerase I inhibitors. Correspondingly, Topo-isomerase I inhibitors effectively and preferentially eliminate AtmKD/-, but not Atm-proficientor Atm-/- leukemia in animal models. These findings identify ATM kinase-domain missense mutations as a potent oncogenic event and a biomarker for Topo-isomerase I inhibitor based therapy.
- Published
- 2016
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