Dr. Kleer received her medical degree from the University of Buenos Aires School of Medicine in Buenos Aires, Argentina in 1993. She began her residency in Anatomic and Clinical Pathology at the Mayo Clinic in Rochester, Minnesota, and completed her training at the University of Michigan in 1999. During her last year of training, she served as a Surgical Pathology Fellow with special interest in breast pathology under the mentorship of Dr. Harold Oberman. In 1999 she joined the faculty as an Assistant Professor, was promoted to Associate Professor with tenure in 2005, and to full Professor with tenure in 2011. In 2007, Dr. Kleer was honored as the first Harold A. Oberman Collegiate Professor in Pathology, a position she currently holds. In addition, she is the chief of the Breast Pathology Program at the University of Michigan. She has been an active member of the Breast Care Center since 1999. Dr. Kleer is the principal investigator of an NIH and DOD-funded research laboratory at the Cancer Center working to understand mechanisms of breast cancer invasion and metastasis, and to develop useful breast tissue-based biomarkers. Her work bridges basic science and clinical application. Dr. Kleer has been participating in NIH and DOD study sections, and was a permanent member of the NIH Study Section Tumor Progression and Metastasis from 2008-2012. In addition to her research and clinical work, Dr. Kleer is a dedicated mentor to medical students, graduate students, and physicians both in the laboratory and in surgical pathology. Many of Dr. Kleer’s trainees have gone on to highly successful academic careers in the US and abroad. In 2013, she was the distinguished recipient of the Ramzi Cotran Young Investigator Award from the United States and Canadian Academy of Pathology. In 2014, Dr. Kleer was inducted into the League of Research Excellence at the University of Michigan Medical School and into the American Society for Clinical Investigation (ASCI).

 Employing pathology, cell and molecular biology, and genetics our laboratory discovered two major events associated with metastasizing breast cancers: overexpression of the epigenetic regulator EZH2 and down-regulation of the matrix protein CCN6 (WISP3). The mechanisms by which these alterations promote breast cancer invasion and metastasis, and their utility as novel tissue biomarkers of prognosis constitute the foundation of our laboratory projects. Our laboratory has identified that EZH2, a repressor of gene transcription, is able to transform mammary epithelial cells. EZH2 overexpression in breast cancer tissue samples is a predictor of metastasis and survival. We have developed the only mouse model of EZH2 overexpression targeted to the mammary gland, which is advancing our understanding on how EZH2 overexpression promotes breast cancer initiation and metastasis. Our recent mechanistic studies led to the discovery of new, non-canonical functions of EZH2 with clinical application. In addition, our laboratory has identified and characterized a novel tumor suppressor gene for aggressive breast carcinomas: CCN6 (WISP3). This secreted extracellular matrix associated protein plays a role in the regulation of growth factor signaling pathways and how they influence breast cancer cells.