Trophoblast surface antigen 2 (TROP2/TACSTD2), also known as gastrointestinal tumour‐associated antigen (GA7331), is a type I cell surface receptor glycoprotein composed of an extracellular domain, a single transmembrane helix, and a short cytoplasmic tail with a phosphatidylinositol 4,5‐bisphosphate (PIP2)‐binding motif, which is tightly regulated and limited in normal adult tissues and frequently overexpressed in multiple human carcinomas. This evidence concerns the gene TACSTD2 and carcinoma.