Many cancer therapeutics, such as EGFR inhibitors, target proteins that are kinases - enzymes that initiate a cascade of signals that tell cells to reproduce. But ERBB3 is a pseudo-kinase; it functions only by binding with other proteins that have kinase activity.

"This study shows that targets that historically hadn't been considered because they don't have the typical activities of a kinase can be equally if not more important in supporting cancer cells," Threadgill said.

Other UNC co-authors are Ming Yu, a former graduate student in the department of genetics and the Program in Oral Biology; Christina Pannicia, former undergraduate student in biology; and Daekee Lee, formerly of the genetics department and now of Ewha Womans University in Seoul, Republic of Korea. Other co-authors are Eunjung Lee, Hyunok Kim and Kyoungmi Kim of Ewha Womans University; and Jonathan M. Kurie and Yanan Yang of the University of Texas M.D. Anderson Cancer Center.

The study was funded by the National Cancer Institute, the National Science Foundation, and the Korea Science and Engineering Foundation.