Researcher has information published
Published 12:00 am Friday, December 6, 2002
Research from Hormel Institute on the role of Leptin, a substance that regulates hunger and obesity and breast cancer on
postmenopausal women, was recently published on the Journal of the National Institute of Cancer.
Dr. Margot Cleary, who has been with the institute for 20 years, became interested in researching obesity as a risk factor for postmenopausal women some years ago.
In 1994, Leptin was discovered. Research showed that it was a protein made directly in the fat tissue. So the heavier the person, the more Leptin they have.
Cleary said one of Leptin's jobs is to travel to the brain where receptors signal if the levels of Leptin are too high, providing feedback for regulation of body weight.
It was later discovered that Leptin receptors are found in other normal tissues of the body and it appears to be involved in the growth of cells. Also, Leptin receptors have been found in malignant lung and gastric cells.
Because obesity is a risk factor for breast cancer in postmenopausal women, Cleary and Dr. Xin Hu decided to investigate if Leptin influences the growth-increase of cancerous cells.
In the study, various methods of experiments were used, including a normal breast tissue cell culture and a breast cancer cell line originally obtained from a 54-year-old woman. When Leptin was added to them, there were increased numbers in both normal and malignant cells. In another aspect of this study it was found that mice that lack Leptin or the Leptin receptor, do not develop normal mammary tissue.
The overall findings correlate with the current hypothesis that high levels of Leptin are associated with obesity may promote breast cancer development,
Results of the study indicated that cell numbers increased in both normal and malignant breast cells.
"It's a complicated issue. There are a number of other factors that may be involved in this relationship that we need to identify," Cleary said.
Ongoing studies collaboration with investigators from the Mayo Clinic will hopefully shed further insights into this relationship, Cleary said.
The research was funded and supported by the Hormel Foundation, the Fraternal Order of Eagles Cancer Research Fund and a Regis Breast Cancer Research Scholarship.
Cleary has submitted the study as a grant application for further funding for the research.
"I thought it was something worth pursuing and the outcome was better than expected," Cleary said.
Roxana Orellana can be reached at 434-2214 or by e-mail at :mailto:roxana.orellana@austindailyherald.com