C-erbB-2/HER-2 is a member of the EGFR family. Receptors of this family are located on the plasma membrane and consist of an extracellular ligand-binding domain that is connected to a large intracellular domain by a single transmembrane sequence. c-erbB-2/HER-2 protein is over-expressed in a variety of carcinomas especially those of breast and ovary.
