Professor and Division Head of Hematology and Oncology, Department of Medicine
University of Wisconsin School of Medicine and Public Health



MB, BcH, BAO (MD equivalent): University College, Dublin, Ireland
Residency: Mater Hospital, Dublin, Ireland
Residency: Medical College Wisconsin, Milwaukee, WI
Residency: Northwestern University, Chicago, IL
Fellowship: Meath Hospital, Dublin, Ireland
Fellowship: Mater Hospital, Dublin, Ireland
Fellowship: Northwestern University, Chicago, IL

Clinical Expertise:

Dr. O’Regan is a nationally recognized expert in breast cancer and specifically focuses on novel therapeutic approaches for hormone refractory and triple negative breast cancer, with a special emphasis in African-American patients. Her research program focuses on identifying mechanisms of resistance to breast-cancer therapies and development of new therapies. Her research group has made significant discoveries about the role of the PI3 Kinase-mTOR pathway in triple-negative breast cancer, showing that mTOR inhibition can sensitize breast-cancer cells to upstream growth-factor inhibitors. These discoveries resulted in a novel clinical trial for patients with metastatic breast cancer.