Emerging targeted therapies for breast cancer.

Overview

Targeted therapies offer a new approach to breast cancer treatment. Rather than eliminating both malignant and normal cells nonspecifically, these so-called "rational" therapies exploit second messenger proteins, ligands, and receptors that are known to be upregulated in neoplastic cells, or are implicated in cancer metastasis. This review will highlight a number of these targets and the mechanisms that have been targeted in drug design. We will also describe recently completed and currently ongoing clinical trials investigating targeted therapies and their potential to augment standard breast cancer therapy.