Yuan-Li Tsai, PhD, Postdoctoral Fellow University of California, San Francisco Area of Research: All Cancers While T cells are critically important for controlling cancer, tumors have the ability to engage immune checkpoints—like PD-1/PD-L1—to suppress the activity of these T cells. Checkpoint immunotherapies that block the PD-1/PD-L1 pathway have provided remarkable benefits for patients in several cancer types, but the majority of patients still don’t respond to them. Thus, it’s clear that more needs to be learned when it comes to stimulating effective immune responses against tumors. Numerous enzymes are known to negatively regulate T cell signaling. One of these is STS (suppressors of T-cell receptor signaling). STS is preferentially expressed in immune cells and has a fundamentally distinct mechanism from others, thus providing a promising potential target for drug development. However, how STS functions remains largely unclear. In order to aid the development of improved immunotherapies, Dr. Yuan-Li Tsai is investigating STS and its role in anti-cancer immune activity. Here, Tsai will characterize how STS influences T cell activity in the context of cancer, which could pave the way for STS-targeting strategies in order to enhance T cell activity, against cancer. Projects and Grants Overcoming immunosuppression by selectively targeting suppressor of T-cell receptor signaling (STS) in T cells University of California, San Francisco | All Cancers | 2020 | Arthur Weiss, MD, PhD