Molecular Analysis and Therapeutic Application. Molecular Targeting for Breast Cancer Treatment.

Abstract

Advanced biotechnologies have provided benefits to detect a variety of cellular molecules for tumor diagnosis, determination of malignancy, and prognosis of cancers. Improved understanding of the molecular basis of cancers will lead to molecular targeted approaches to cancer prevention and treatment. Monoclonal antibody−based therapeutics targeting cell surface receptor such as HER2/neu/c−erbB2 oncoprotein on breast cancer cells has shown efficacy in clinical trials. HER2 pro−oncogene is a member of the epidermal growth factor receptor family, and HER2 oncoprotein is a well−characterized predictor of tumor aggressiveness. The overexpression of HER2 has been found in about 25% to 30% of breast cancers and associated with poor prognosis, resistance to hormonal therapy and lack of sensitivity to some adjuvant chemotherapy. The recombinant anti−HER2 monoclonal antibody, trastsuzumab(Herceptin), was evaluated in clinical trials for treatment of HER2−over−expressing metastatic breast cancers. The administration of the trastuzumab has produced an objective response in patients with metastatic breast cancers, suggesting that the trastuzumab will be a new molecular targeting therapeutic agent for patients with HER2−overexpressing cancer. Thus, a test result of HER2 overexpression will be a valid criterion in determining eligibility for the trastsuzumab therapy, and reliable detection of HER2 overexpression is an important prerequisite for the success of the trastsuzumab therapy.