1. From the Institute of Pathology, Faculty of Biology and Medicine, University of Lausanne and Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland (N.R., I.S.); and the Department of Pathology and Center for Cancer Research, Massachusetts General Hospital and Harvard Medical School, Boston, and the Broad Institute of Harvard University and the Massachusetts Institute of Technology, Cambridge — both in Massachusetts (M.L.S.).