HER2 [ERBB2/3257]

HER2 is a receptor tyrosine kinase of the c-erbB family. It is closely related in structure 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.HER2 is one of the four members of the ErbB receptor family of transmembrane receptor-like tyrosine kinases. The kinase activity of ErbB2 can be activated without ligand if it is overexpressed, and by association with other ErbB proteins. Overexpression of ErbB2 is detected in almost 40% of human breast cancers. Each laboratory should validate it by its own procedure.