Researchers receive grants for breast cancer work

Two groups of Colorado breast cancer researchers have received $1.625 million in grants to better understand the role of stem-like breast cancer cells in treatment resistance and recurrence.

University of Colorado Cancer Center (UCCC) researcher Carol Sartorius, Ph.D., received a $1.25 million grant from the National Cancer Institute to investigate the role of stem-like cells in estrogen receptor-positive (ER+) breast cancer. Sartorius, associate professor of endocrinology at the University of Colorado School of Medicine (SOM), was the first person to show that the hormone progesterone regulates a stem-like cell phenotype in breast cancer.

In a July 28, 2010 paper in Breast Cancer Research Treatment, Sartorius and UCCC breast-cancer researcher and clinician Peter Kabos, M.D., assistant professor of medical oncology at the SOM, identified a pool of cells that lose both estrogen and progesterone receptors and gain expression of the protein cytokeratin 5. They showed that cells expressing cytokeratin 5 tend to survive treatment and endocrine therapy— a hallmark of stem-like cells.

Sartorius says the grant will allow her to figure out how these cytokeratin 5-expressing cells are regulated in ER+ breast cancer and how they make the tumor more drug-resistant. She will collaborate with UCCC researcher Dan LaBarbara, Ph.D., assistant professor of pharmaceutical sciences at the University of Colorado School of Pharmacy, to figure out whether the cells can be targeted with novel drugs.

Sartorius also is working with UCCC researcher Jennifer Richer, Ph.D., associate professor of pathology at the SOM, who is an expert in the role of microRNAs in breast cancer. They received a $375,000 Idea Grant from the Department of Defense to narrow down which of a group of microRNAs are involved in changing cells from being differentiated to being stem-like. Kabos also will collaborate on the DOD grant.