Trastuzumab use

Several drugs inhibit an epidermal growth factor receptor (EGFR) that is distinct from the HER-2/neu receptor for the epidermal growth factor that is targeted by trastuzumab. The EGFR regulates signaling pathways involved in cellular proliferation, invasion and metastasis, and angiogenesis. It is also implicated in inhibiting the cytotoxic activity of some anticancer drugs and radiation therapy. The drug, usually administered with paclitaxel, can cause regression of breast cancer and metastases in a small percentage of these individuals. [Note: At least 50 tyrosine kinases mediate cell growth or division by phosphorylating signaling proteins. They have been implicated in the development of many neoplasms by an unknown mechanism.]