Approximately 26 percent of African-America women with breast cancer are triple-negative, compared to 15 percent of Caucasian women.
“Even though this is one of the least common types of breast cancer, it is among the most aggressive, has a poor prognosis, and there are no targeted treatments against it,” said Dr. Michael Lewis, associate professor in the Smith Breast Center.
The subtype is referred to as “triple negative” because it does not express estrogen or progesterone receptors, or the human epidermal growth factor receptor 2 (HER2) oncogene.
Estrogen-receptor positive (with or without progesterone receptor), and HER2-positive are other subtypes of breast cancer. All have targeted treatments available for their genetic malfunctions.
Currently, triple negative breast cancer is treated with a combination of chemotherapy and surgery.
Lewis and his team hope to contribute to overcoming this problem by collaborating with researchers from the University of Michigan at Ann Arbor, the Karmanos Cancer Institute of Wayne State University, the Henry Ford Cancer Center in Detroit and the Van Andel Research Instutitue (VARI)/Translational Genomics Research Institute (TGEN) on a recent Susan G. Komen for the Cure Promise grant that will investigate treatments that target cancer stem cells in triple negative breast cancer.
Led by Dr. Max S. Wicha at the University of Michigan, the team received $3.5 million to investigate potential treatments that target these tumor-originating cells that fuel the tumor’s growth and spread.
The consortium will test four different experimental drug combinations to see which best targets cancer stem cells specifically (these are thought to be among the cells that remain following chemotherapy).
They will test this using human tumor tissue grown in mice (called xenografts), developed in the Lewis lab.
“This is a unique research tool because tissues seem to behave similarly in mice, as they do in humans,” said Lewis. “It should give us a good glimpse into how we can better treat this subtype.”