Lieping Chen

Biography
Lieping Chen is one of the founding figures of modern cancer immunotherapy, whose work gave oncology both a new class of treatment and a way to identify patients most likely to benefit. In 1999, his laboratory discovered B7-H1, now also known as PD-L1, and established the PD-1/PD-L1 pathway as a mechanism by which tumors evade immune attack. This work helped lay the foundation for checkpoint blockade, part of the cancer immunotherapy revolution named Science’s 2013 Breakthrough of the Year. Chen went on to co-initiate the first-in-human clinical trial of PD-1/PD-L1 blockade in 2006 and pioneered PD-L1 tumor staining as a predictive biomarker, work that informed FDA approvals and helped redefine treatment across multiple cancers. His contributions began even earlier with foundational work showing that B7-CD28/CTLA-4 family molecules could be manipulated to strengthen antitumor immunity. He is a member of the National Academy of Sciences and the National Academy of Medicine.