Grant: Project Grant

Breast cancer remains a prevalent disease and major cause of morbidity in women. Amongst the most prevalent oncogene drivers in breast cancer is the Estrogen Receptor alpha (ERa), one of the major receptors for estrogens. Treatment of ERa positive breast cancer involves the use of Selective Estrogen Receptor Modulators (SERMs) such as tamoxifen. Despite the successful development of tamoxifen and other SERMs, the emergence of recurrent breast cancers that acquired resistance to these agents remains a major clinical challenge. One common mode of acquired resistance to these anti-estrogen therapies is acquisition of activating mutations within the ERa that render it ligand independent. In this CIHR proposal, we plan to use an recently established mouse model that expresses this ERa mutant in the mammary epithelium to evaluate its role in breast cancer progression and as preclinical model to test the efficacy of novel SERMs.