NECTIN4 and adenocarcinoma: Given the limited expression of Nectin-4/PVRL4 in normal tissues including the skin, hair follicles, trachea, and lung51,52, but elevated expression in many adenocarcinomas such as breast, lung, bladder, pancreatic, and ovarian cancers8,10,11,53,54, Nectin-4/PVRL4 has emerged as an important tumor marker and therapeutic target.