Used primarily in cancer research, Nutlin-3b acts as a potent inhibitor of the MDM2-p53 protein-protein interaction. By blocking MDM2 from binding to the tumor suppressor p53, it stabilizes and activates p53, leading to cell cycle arrest and apoptosis in cancer cells. It is widely employed in studies involving tumors with wild-type p53, such as certain leukemias, sarcomas, and solid tumors. Its application extends to combination therapies, where it enhances the efficacy of chemotherapeutic agents and radiation. Due to its role in reactivating p53 pathways, Nutlin-3b serves as a valuable tool for probing p53-dependent mechanisms and developing targeted anticancer drugs.