Menopause combined with obesity and overeating encourages Breast Cancer Tumor Growth
(Best Syndication News) - Using a rat model, researchers investigated breast tumor growth associated with menopause, obesity and overeating. The rat model demonstrated the potential increased risk for breast-cancer tumor growth and progression with post-menopausal women who are obese and overeat. The results were published in the American Association for Cancer Research journal, Cancer Research.
Paul S. MacLean, Ph.D., associate professor of medicine at the University of Colorado Anschutz Health and Wellness Center in Aurora, Colorado explained that obese post-menopausal women are at an increased risk for developing breast cancer and for having less desirable clinical outcomes.
The researchers wanted to identify and understand the increased risk factors using rats. Previously, MacLean and his colleagues used a model demostrating that surgically removing a rat’s ovaries (ovariectomy) was associated with increased breast tumor development. The rats gained weight after the procedure, which they referred to as ovariectomy modeled menopause.
In the most recent study, the researchers confirmed obesity combined with overfeeding after an ovariectomy promoted aggressive breast tumor growth and progression.
Overfed lean rats were able to store extra glucose and dietary fat in their liver, fat, muscle, and healthy breast tissue, which is a normal response. However, the obese rats did not increase glucose and dietary fat uptake in healthy tissues, instead the breast tumors showed a dramatic intake for glucose uptake. Additionally, on the molecular level, the obese rats had showed increased expression of the progesterone receptor (PR). Postmenopausal women also demonstrated a similar expression of genes with PR-positive breast tumors.
MacLean said the obese rats had reduced their tumor burden when given an anti-diabetic drug called metformin after getting their ovaries removed.
During the perimenopausal time - the time just before the menstrual cycle stops completely - women should restrict food intake and increase exercise to help reduce breast cancer risk. Metformin and perimenopausal medications may also help as well.
By: Marsha Quinn