11-934 Factor Bldg.
UCLA Med-Hemat & Onc
Los Angeles, CA 90095
Phone: (310) 206-9168
Professor, Biological Chemistry
Signal Transduction and Gene Expression
Cell growth, differentiation, survival, and apoptosis can be regulated by cytokines, growth factors, and cellular stresses that trigger distinct as well as overlapping signaling pathways. Abnormal signaling is associated with human cancer. The overall research interest in my laboratory is to study cellular signal transduction pathways in normal and tumor cells. These studies may provide novel therapeutic targets for cancer treatment.
Our work is currently centered in two areas: 1) To study the role of PIAS (protein inhibitor of activated STAT) proteins in cellular signaling. In studies aimed at the understanding of cytokine-activated JAK-STAT signaling pathway, our laboratory has discovered the PIAS family of proteins, which can inhibit the activity of STATs. In addition, PIAS proteins have also been shown to possess SUMO (small ubiquitin-related modifier) E3 ligase activity and can regulate a number of other transcription factors, including p53 and androgen receptor. We are studying the molecular mechanism, the regulation, and the biological roles of PIAS proteins in cellular signaling using a combined biochemical and genetic approach. 2) To study the regulation of the JAK-STAT signaling pathway. Cytokines bind to their cell surface receptors to activate signal transduction pathways that regulate numerous fundamental cellular processes, including cell growth and differentiation, immune and inflammatory responses. The JAK-STAT pathway is widely utilized by many cytokines and is regulated at multiple steps. The study on the regulation of the JAK-STAT pathway is important since abnormal JAK-STAT signaling is associated with immune diseases and cancers. Our laboratory is studying several regulatory mechanisms in the JAK-STAT pathway, including the dephosphorylation of STATs by protein tyrosine phosphatases and the regulation of the JAK-STAT pathway upon viral infection.