This non-therapeutic biosimilar antibody uses the same variable regions from the therapeutic antibody Pertuzumab making it ideal for research use. This Pertuzumab biosimilar reacts with the extracellular dimerization domain of human HER2 (human epidermal growth factor receptor 2) also known as neu peptide, CD340, ErbB-2, and p185. HER2 is a 185 kDa transmembrane, receptor-like glycoprotein with intrinsic tyrosine kinase activity that is part of several cell surface receptor complexes. HER2 lacks an identified ligand however, the kinase can be activated in the absence of a ligand when overexpressed. HER2 is a proto-oncoprotein that is commonly overexpressed on a variety of different tumors. Approximately 40% of human breast cancers overexpress HER2. HER2 overexpression is associated with poorer overall survival rates, shorter times to disease progression, and increased resistance to chemotherapy. Because of these clinical characteristics anti-HER2 monoclonal antibody therapy is now a standard for the treatment of advanced breast cancers that overexpress HER2. Pertuzumab is used for the treatment of HER2-positive metastatic breast cancer. By binding to HER2, Pertuzumab inhibits the dimerization of HER2 with other HER receptors, resulting in slowed tumor growth.