A 60 year old female presented with breast carcinoma and she was prescribed herceptin (trastuzumab). Which of the following statement regarding this drug is TRUE?
It is an antibody produced entirely from mouse containing no human component
It is a monoclonal antibody produced by injecting her-2 antigen
Injection of herceptin increases antibody response
The protein HER2/Neu is expressed in increased amount by breast cancer cells
Trastuzumab (HERCEPTIN) is a humanized monoclonal antibody that binds to the external domain of HER2/neu (ErbB2). Trastuzumab was the first monoclonal antibody to be approved for the treatment of a solid tumor. Thiy percent of breast cancers overexpress this receptor due to gene amplification on chromosome 17. Also Know: Trastuzumab exes its antitumor effects through several putative mechanisms of action: inhibition of homo- or heterodimerization of receptor, thereby preventing receptor kinase activation and downstream signaling; initiation of Fc-receptor-mediated antibody-dependent cellular cytotoxicity; and blockade of the angiogenic effects of HER2 signaling. Ref: Chabner B.A., Barnes J., Neal J., Olson E., Mujagic H., Sequist L., Wilson W., Longo D.L., Mitsiades C., Richardson P. (2011). Chapter 62. Targeted Therapies: Tyrosine Kinase Inhibitors, Monoclonal Antibodies, and Cytokines. In L.L. Brunton, B.A. Chabner, B.C. Knollmann (Eds), Goodman & Gilman's The Pharmacological Basis of Therapeutics, 12e.