More than $1.5 million for breast cancer research has been awarded to Dr. Margot Cleary, leader of the Nutrition and Metabolism section at The Hormel Institute, University of Minnesota and Mayo Clinic.

Funded through 2016, the federal grant will support research to determine whether metformin (Glucophage), a commonly prescribed Type 2 diabetes drug, has cancer-preventive qualities. Studies performed by Cleary and her research team will study if metformin treatment offers similar actions as calorie restriction in preventing mammary tumors.

Research under the grant — approved by the National Cancer Center, part of the National

Institutes of Health — also will help determine if body-weight status affects the anti-cancer actions of metformin and calorie restriction.

“This research is important because there is an increasing awareness

Nutrition and Metabolism that obesity and being overweight increase women’s risk for postmenopausal breast cancer,” Cleary said.

Interest in metformin as an anticancer agent has developed from studies of people with adult onset (Type 2) diabetes mellitus. There seems to be a reduced overall cancer mortality/incidence in diabetic people treated with metformin compared to other diabetes therapies, Cleary said.

Subsequent studies showed a specific effect for breast cancer incidence, she

said, leading her to pursue researching whether metformin could be used

independently of diabetes to prevent cancer.

The number of women potentially at increased risk for developing breast cancer due to their body weight status is quite high, given the high number of obese women worldwide, including about 18 million in the United States, Cleary said. Although the risk created by increased body weight is not as high as that associated with some genetic defects or family history of breast cancer, the overall impact potentially affects many women due to the large number of them who are overweight or obese.

“Identification of a safe and effective compound that women at increased risk could be prescribed would affect many women,” Cleary said. “Presently, there are several other compounds that can be taken but these have potentially serious side effects.”

The work will be done in collaboration with Dr. Adrian Hegeman of the University of Minnesota’s Departments of Horticultural Sciences & Plant Biology, Microbial & Plant Genomics Institute. Hegeman will help with serum measurements as well as the effects of interventions on proliferation of precursor cancer cells. Members of the Cleary lab working on the project include Dr. Christine Seppanen, Dr. Michael Grossmann, Dr. Daqing Wang and Nancy Mizuno.