1. Laboratory of Molecular Pharmacology and Developmental Therapeutics Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
2. DNA Damage Response Biology, Oncology IMED, AstraZeneca, Hodgkin Building, B900 Chesterford Research Park, Little Chesterford, Cambridge CB10 1XL, U.K.
3. Drug Development Unit, Institute of Cancer Research and Royal Marsden National Health Service Foundation Trust, London SM2 5PT, U.K.