The Breast Cancer-Body Fat Enigma: Paradoxical Changes in Fat and Serum Biomarkers in Response to Fatty Acid Intake.
Robert W Hardy, Ming-Che Shen, Lynda M Evans, Eric C Toline, Renee A Desmond, Gene P Siegal. University of Alabama at Birmingham
Background: Stearate is a long-chain saturated fatty acid (C18:0) that has been shown to decrease breast cancer cell proliferation, migration and invasion in vitro, and reduce tumor growth and metastasis in vivo. Obesity is a risk factor for breast cancer. Our hypothesis was that dietary stearate inhibited breast cancer in part by decreasing body fat. Our goal was to determine whether there was an association between dietary stearate and adipose tissue.
Design: Four groups of 10 athymic mice each were fed 1 of 4 diets for 18 weeks (low fat diet, 5% corn oil; stearate diet, 17% stearate and 3% safflower oil; corn oil diet, 17% corn oil and 3% safflower oil; safflower oil diet, 20% safflower oil). Body composition was assessed by quantitative magnetic resonance (QMR) spectroscopy and dual energy X-ray absorptionmetry (DXA). Serum concentrations of glucose, leptin, adiponectin, insulin, IL-6 and monocyte chemoattractant protein-1 (MCP-1) were also determined.
Results: In a repeated measures model for total body fat (TBF) and total body lean mass (TBLM) the stearate group had significantly reduced TBF compared to the low fat group (p=0.003); mice on the high fat diets (stearate, corn oil and safflower oil) had significantly increased TBLM compared to the low fat group (p<0.001, 0.002 and <0.001, respectively). Mice on the stearate diet had significantly reduced kidney weight compared to the other diet groups (low fat, p=0.025; corn oil, p=0.003; safflower oil, p=0.013); mice on the stearate diet had significantly less abdominal fat compared to the low fat and corn oil groups (p<0.001 and 0.004, respectively). Mice on the stearate diet had significantly reduced level of glucose compared to the low fat and safflower oil groups (p=0.018 and <0.001, respectively). Mice on the high fat diets (stearate, corn oil and safflower oil) had significantly reduced level of leptin compared to the low fat group (p=0.002, 0.031 and 0.002, respectively), and mice on the stearate and safflower oil diets had significantly reduced level of leptin compared to the corn oil group (p=0.023 and 0.003, respectively). Mice on the stearate diet had significantly increased level of MCP-1 compared to the low fat and safflower oil groups (p=0.016 and 0.021, respectively).
Conclusions: Studies have suggested that glucose and leptin have cancer promoting effects, while MCP-1 may promote or inhibit breast cancer. Overall these data have supported our hypothesis that dietary stearate decreases total body fat, and that this decrease in body fat may be related to stearate inhibition of breast cancer.
Tuesday, March 1, 2011 1:00 PM
Poster Session IV # 12, Tuesday Afternoon