Plogosertib (CYC140) is a selective, potent, and orally active ATP-competitive PLK1 inhibitor (IC50: 3 nM). Plogosertib is an anti-cancer agent with anti-proliferative activity. Plogosertib can be used in the research of several tumors, including esophageal, gastric, leukemia, non–small cell lung cancer, ovarian, and squamous cell cancers.