Challenges and expectations for novel biologics discovery in HER2-negative breast cancer

Approximately half a century after the discovery of the human epidermal growth factor (hEGF) and its receptor type 2 (HER2), biologically targeted agents such as trastuzumab and lapatinib may improve oncological outcomes of breast cancer patients whose tumors cancer cells overexpress HER2. The HER2 status has been a standard prognostic factor and patients with breast cancer are classified into HER2-negative and HER2-positive disease. Although prognosis of patients with HER2-positive cancer, as compared to HER2-negative is poorer, the addition of the monoclonal antibody trastuzumab or the tyrosine kinase inhibitor small molecule lapatinib may alter this poor outcome.