TROP-2

TROP-2, encoded by TACSTD2 and also called tumor-associated calcium signal transducer 2, is a single-pass transmembrane glycoprotein structurally related to EpCAM, with an extracellular region containing cysteine-rich and thyroglobulin type-1 domains. It participates in cell adhesion, cell cycle progression, and calcium signaling, although its full physiological function remains incompletely resolved. Normal epithelia express TROP-2 at low levels, whereas many carcinomas of the breast, lung, bladder, and pancreas overexpress it markedly. The dense tumor expression made TROP-2 the target of the antibody-drug conjugates sacituzumab govitecan and datopotamab deruxtecan, now central agents in solid tumor therapy.