Human trophoblastic cell surface antigen 2 (Trop-2) is a transmembrane glycoprotein that is expressed at a low level in normal epithelial cells but at a high level in many solid tumours. It regulates tumour growth, invasion and spread by several signalling pathways, and has a role in stem cell biology and other diseases. Furthermore, overexpression of Trop-2 in tumours has been associated with poor prognosis. This mini-review will briefly summarise the available clinical data on treatment with Trop-2-directed antibody-drug conjugates (ADCs) in the field of breast cancer.
