Author Contributions: Drs Gentles and Alizadeh had full access to all the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.
Study concept and design: Gentles, Plevritis, Majeti, Alizadeh.
Acquisition of data: Gentles, Majeti, Alizadeh.
Analysis and interpretation of data: Gentles, Plevritis, Majeti, Alizadeh.
Drafting of the manuscript: Gentles, Plevritis, Majeti, Alizadeh.
Critical revision of the manuscript for important intellectual content: Gentles, Plevritis, Majeti, Alizadeh.
Statistical analysis: Gentles, Plevritis, Alizadeh.
Obtained funding: Plevritis, Majeti.
Administrative, technical or material support: Plevritis, Majeti, Alizadeh.
Study supervision: Majeti, Alizadeh.
Financial Disclosures: A patent application for the development of the leukemic stem cell score as a diagnostic assay has been submitted by Drs Gentles, Majeti, and Alizadeh. Dr Plevritis did not report any financial disclosures.
Funding/Support: This research was supported by the Integrative Cancer Biology Program through National Institutes of Health awards 1U54CA149145 and U56-CA112973 (Dr Plevritis). Dr Majeti holds a Career Award for Medical Scientists from the Burroughs Wellcome Fund. Dr Alizadeh holds a Career Development Award from the Leukemia and Lymphoma Society.
Role of the Sponsors: The funding organizations had no role in the design and conduct of the study; in the collection, analysis, and interpretation of the data; or in the preparation, review, or approval of the manuscript.
Additional Contributions: We thank Irving Weissman, MD, and Ronald Levy, MD, for support and discussion and Rob Tibshirani, PhD, for advice on statistical analyses (all 3 from Stanford University, Palo Alto, California). We also thank the following Stanford University clinicians for critically reading the manuscript: Bruno Medeiros, MD, Jason Gotlib, MD, Linda Boxer, MD, PhD, and Beverly Mitchell, MD. We are indebted to the patients and their physicians, including the Stanford Hematology Tissue Bank, the German AML Cooperative Group, the Haemato-Oncology Foundation for Adults in the Netherlands, the Southwest Oncology Group, the German AML Study Group/Ulm, Washington University School of Medicine, and the Cancer and Leukemia Group B, for sharing raw data and clinical information from their studies. We also thank Fumihiko Ishikawa, MD, PhD, and Atsushi Hijikata, MSc, for providing access to their microarray data from purified AML subsets (RIKEN). No persons or groups acknowledged in this section received compensation.