A cell-based screen identifies ATR inhibitors with synthetic lethal properties for cancer-associated mutations.

Oncogene activation has been shown to generate replication-born DNA damage, also known as replicative stress. The primary responder to replicative stress is not Ataxia-Telangiectasia Mutated (ATM) but rather the kinase ATM and Rad3-related (ATR). One limitation for the study of ATR is the lack of po...

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Bibliographic Details
Authors: Toledo, Luis I, Murga, Matilde, Zur, Rafal, Soria, Rebeca, Rodriguez, Antonio, Martinez, Sonia, Oyarzabal, Julen, Pastor, Joaquin, Bischoff, James R, Fernandez-Capetillo, Oscar
Format: article
Publication Date:2011
Country:España
Institution:Instituto de Salud Carlos III (ISCIII)
Repository:Repisalud
Language:English
OAI Identifier:oai:repisalud.isciii.es:20.500.12105/17684
Online Access:http://hdl.handle.net/20.500.12105/17684
Access Level:Open access
Keyword:Animals
Antineoplastic Agents
Ataxia Telangiectasia Mutated Proteins
Cell Cycle Proteins
Cell Survival
Cells, Cultured
Chromosome Breakage
Drug Screening Assays, Antitumor
Enzyme Inhibitors
Fibroblasts
Imidazoles
Mice
Oxazines
Protein Serine-Threonine Kinases
Quinolines
Tumor Suppressor Protein p53
Description
Summary:Oncogene activation has been shown to generate replication-born DNA damage, also known as replicative stress. The primary responder to replicative stress is not Ataxia-Telangiectasia Mutated (ATM) but rather the kinase ATM and Rad3-related (ATR). One limitation for the study of ATR is the lack of potent inhibitors. We here describe a cell-based screening strategy that has allowed us to identify compounds with ATR inhibitory activity in the nanomolar range. Pharmacological inhibition of ATR generates replicative stress, leading to chromosomal breakage in the presence of conditions that stall replication forks. Moreover, ATR inhibition is particularly toxic for p53-deficient cells, this toxicity being exacerbated by replicative stress-generating conditions such as the overexpression of cyclin E. Notably, one of the compounds we identified is NVP-BEZ235, a dual phosphatidylinositol-3-OH kinase (PI3K) and mTOR inhibitor that is being tested for cancer chemotherapy but that we now show is also very potent against ATM, ATR and the catalytic subunit of DNA-dependent protein kinase (DNA-PKcs).