Authors' Affiliations: 1Division of Molecular and Cellular Oncology, Department of Radiation Oncology, and 2Pasarow Mass Spectrometry Laboratory, Department of Psychiatry and Behavioral Science, David Geffen School of Medicine at University of California at Los Angeles, Los Angeles, California; and 3Center of Cancer Systems Biology, Caritas St. Elizabeth's Medical Center, Tufts University School of Medicine, Boston, Massachusetts (At 2010-10-31)