c-erbB-2 is a receptor tyrosine kinase of the c-erbB family. It is closely related instructure to the epidermal growth factor receptor. c-erbB-2 oncoprotein is detectable in a proportion of breast and other adenocarconomas, as well as transitional cell carcinomas. In the case of breast cancer, expression determined by immunohistochemistry has been shown to be associated with poor prognosis Synonyms: Receptor tyrosine-protein kinase erbB-2, EC 2.7.10.1, p185erbB2, C-erbB-2, NEU proto-oncogene, Tyrosine kinase-type cell surface receptor HER2, MLN 19, CD340 antigen, NEU, NGL, HER2, TKR1, HER-2, c-erb B2, HER-2/neu