About the Authors

Grace Ka Yan Chan

Affiliation Department of Biochemical and Cellular Pharmacology, Genentech, Inc. South, San Francisco, California, United States of America

Tracy L. Kleinheinz

Affiliation Department of Biochemical and Cellular Pharmacology, Genentech, Inc. South, San Francisco, California, United States of America

David Peterson

Affiliation Department of Discovery Oncology, Genentech, Inc. South San Francisco, California, United States of America

John G. Moffat

moffat.john@gene.com

Affiliation Department of Biochemical and Cellular Pharmacology, Genentech, Inc. South, San Francisco, California, United States of America

Competing Interests

GKYC, TLK and JGM hold stock in Roche. All authors are employees of Genentech, a member of the Roche Group. There are no patents, products in development or marketed products to declare. This does not alter the authors' adherence to all the PLOS ONE policies on sharing data and materials.

Author Contributions

Conceived and designed the experiments: GKYC TLK DPP JGM. Performed the experiments: GKYC TLK DP. Analyzed the data: GKYC DP JGM. Contributed reagents/materials/analysis tools: JM. Wrote the paper: GKYC JGM.