Young Choi, MD

Currently, ERa is the main therapeutic and prognostic marker for breast cancer but about 30% do not respond to the antiestrogens. Some studies have shown that ERb isoforms are predictive marker to antiestrogens. ERb isoforms also are significantly expressed in ERa negative tumors. Thus, ERb may be the potential targeted therapy in some ERa and ERa negative breast cancers. ERb isoforms mRNA by qPCR and protein expression by immunohistochemistry will be tested in both ERa positive and ERa negative breast cancer tissues, and also breast cancer cell lines (BCC). Then BCC will be subjected to estrogens and different antiestrogens to determine their responses, and their effects and analyzed for their potential therapeutic effects. We hypothesize that ERß will eventually play an important role in controlling growth of breast cancers. We believe that ERb isoforms may be new potential therapeutic targets to the patients with non-responder to the current available ERa targeted antiestrogen therapy, and also ERa negative breast cancers who have not received the benefit of the current antiestrogen therapy.