Gemma N. Jones et al has recently published in the British Journal of Cancer an article revealing pRAD50 (Ser635) as a pharmacodynamic biomarker of ATM (AZD0156) and ATR inhibitors (AZD6738) to treat cancers. doi:10.1038/s41416-018-0286-4
Key sensors of DNA damage such as ATM and ATR are targets of choice for drug discovery. A useful screening method is based on synthetic lethality. The pre-screening can be done on convenient HeLa cells.