1. The Breakthrough Breast Cancer Research Centre, Institute of Cancer Research, London, SW3 6JB, UK
2. Department of Biomedical Sciences and Human Oncology, University of Turin, Italy
3. Centro Nacional de Investigaciones Oncológicas (CNIO), Madrid, Spain
4. Institute of Pathology, Paderborn, Germany
5. Hospital Universitario Virgen del Rocío, Seville, Spain