SERPINE1 and esophageal squamous cell carcinoma: The study cohort consisted of 252 cases from four hospitals in three different districts in China with a high incidence of ESCC (Guangdong, Hebei, and Henan).25,26 Eventually, an immune-related signature based on four genes (SERPINE1, MMP12, PLAUR, and EPS8) with real-time quantitative polymerase chain reaction (qPCR) value was constructed and well-validated in multiple institutions.