Titles and Affiliations

Professor of Pharmacology and Chemical Biology
Professor & Vice Chair for Precision and Translational Pharmacology
Director of Education, Women's Cancer Research Center
Magee Women's Research Institute
University of Pittsburgh Cancer Institute
Pittsburgh, Pennsylvania

Research area

Understanding the biology of invasive lobular carcinoma, a common but understudied form of breast cancer.


Invasive lobular carcinoma (ILC) is the second most common subtype of breast cancer after invasive ductal carcinoma (IDC), yet we have a limited understanding of the disease. Despite recent progress, a major challenge is the tremendous heterogeneity within ILC. This has been observed and described by pathologists for many years but has not been studied at the molecular level. Dr. Oesterreich and her team identified a variety of distinct molecular subtypes and variants among ILC tumors that could be very informative for treatment and prognosis. Her hope is that these studies will inform precision medicine for lobular disease.

Progress Thus Far

The team began a detailed analysis of mixed invasive/ductal (mDLC). Given that mDLC shares features with both ILC and IDC, it is important to understand how this affects its disease progression, resistance to therapy, and metastasis. They hypothesized that mDLC is a mix of ductal and lobular tumor components which may show shared and unique molecular features and disease progression drivers compared to IDC and ILC. Ultimately, they will comprehensively characterize the clinicopathological features of mDLC and determine genomic and molecular drivers of mDLC progression. 

What’s next

In the coming year, the team will continue their research on ILC heterogeneity, specifically studies on mDLC, and will extend the studies to include another unique ILC subtype, called pleomorphic ILC (pILC). This is an ILC variant characterized by more aggressive behaviors and worse outcomes.


The main interest of Dr. Oesterreich’s research is to further our understanding of hormone action in women’s cancer in order to use this knowledge for improved diagnosis and endocrine treatment. Her studies have focused on breast cancer and in receptor action in ovarian cancer. Her lab studies how the estrogen receptor (ER) functions, how its activity is regulated by diverse signaling pathways and through coregulator proteins, and if and how these mechanisms are perturbed in cancer cells. The Oesterreich lab is interested in novel concepts of ER action, such as its role in repression of gene transcription and its role in epigenetic marks in the genome. Dr. Oesterreich’s lab has also a strong interest in situ and invasive lobular disease, with a focus on estrogen and antiestrogen response. In her role as Director of Training in the Women's Cancer Research Center, she is interested in providing outstanding training opportunities to the next generation of women's cancer researchers.