 Guan currently is a professor of the Department of Pharmacology and the Moores Cancer Center at University of California, San Diego (UCSD).Guan's research focuses on cancer biology and the intracellular signal transduction in cell growth regulation.Guan has made seminal contributions in the fields of protein tyrosine phosphatase, Mitogen-Activated Protein (MAP) kinase, and the mammalian Target of Rapamycin (mTOR) pathways.