Chipping away at breast cancer: insights from microarray studies of human and mouse mammary cancer.

Breast cancer is the most prevalent tumor in American woman. Multiple factors, including age, diet, genetics, environment, geographic location, parity, as well as race, influence the development of this heterogeneous disease. As the process of oncogenesis involves the disruption of diverse cellular pathways including cell cycle, growth, survival, and apoptosis, the high throughput technique of microarray analyses provides a powerful insight into multiple cellular processes. These techniques have identified particular expression patterns that can classify tumors into new groups and aid in the prediction of the natural history of the disease and the therapeutic response. This wealth of information may also form the basis for the development of new types of targeted therapies. Studies to identify the earliest molecular events in oncogenesis and progressive changes in the human disease have been difficult to perform within the same patient. The use of transgenic mouse mammary cancer models provides an opportunity to decipher molecular changes that occur at progressive stages of tumor development. This paper reviews microarray technology, and the insights gained from published breast cancer microarray analyses, and considers the contribution of microarray studies in identifying mouse cancer models that may be appropriate for answering particular experimental questions.