I am doing early-stage drug discovery for breast cancer. The majority of breast cancer is hormonal receptor (estrogen receptor) driven and is treatable with endocrine therapy; however, at least half of these cancers are refractory or develop resistance to therapy within five years, leaving these patients with only toxic chemo-therapy. I am addressing the problem from three strategic directions - development of selective human estrogen receptor partial agonists (ShERPAs); development of orally bioavailable selective estrogen receptor degraders (SERDs); and development of estrogen-signaling dependent epigenetic vulnerability.