TACSTD2 and neoplasm: Trophoblast surface antigen 2 (Trop2), also known as tumor-associated calcium signal transducer, is a class of cell surface glycoproteins (Lipinski et al. 1981), elevated levels of Trop2 is closely interrelated to poor prognosis and higher risk of metastasis in various tumors, such as in oral, gastric, thyroid and pancreatic cancer (Fong et al. 2008a, b; Mühlmann et al. 2009; Sun et al. 2021).