Watch Dr. Hursting talk about his latest findings on WJZY/Fox News Charlotte.
Stephen Hursting, PhD, MPH, with the UNC Lineberger Comprehensive Cancer Center, UNC Gillings School of Global Public Health and the UNC Nutrition Research Institute at the NC Research Campus in Kannapolis, leads a team of researchers who explore the link between cancer, obesity and diet. The team’s most recent findings illustrate ways that diet can help reduce the cancer-promoting effects of obesity.
Study Finds Weight Loss Amount is More Important then Diet Type in Reversing Cancer, Obesity and Diet Link
Researchers striving to break the link between obesity and cancer have found in a new preclinical study that significant weight loss through calorie restriction, but not moderate weight loss through a low-fat diet, was linked to reduced breast cancer growth. The preliminary findings (abstract #4321) will be presented from 1-5 p.m. April 19 at the 2016 American Association for Cancer Research Annual Meeting in New Orleans.
In the study, researchers with the UNC Lineberger Comprehensive Cancer Center examined whether weight loss via four different diets was linked to reduced tumor growth in laboratory models of breast cancer. While tumor size did not differ between obese mice and obese mice that returned to a normal weight on a low-fat diet, they did find that obese mice that lost significant amounts of weight on three calorie-restricted diets had smaller tumors.
“Based on our results, it appears that the degree of calorie restriction, and hence the amount of weight lost, matters more than the specific dietary changes used to generate the weight loss,” said Laura Bowers, PhD, a postdoctoral fellow in the UNC Lineberger Cancer Control Education Program. “Our findings are too preliminary to make any kind of recommendation for people. The overall message is that the breast cancer-promoting effects of chronic obesity may not be easily reversible with moderate weight loss, but more severe weight loss diets may be effective regardless of whether carbohydrate or fat is restricted.”
Bowers works in the lab of Stephen Hursting, PhD, MPH, a UNC Lineberger member and professor in the UNC Gillings School of Global Public Health and the UNC Nutrition Research Institute. The study is part of the research effort by Hursting’s laboratory to understand, and potentially reverse, the cancer-promoting effects of obesity.
Anti-Inflammatory Diet May Fight Breast Cancer
Promising work is underway in the laboratory of Dr. Stephen Hursting at the NRI to identify dietary interventions that can reduce the risk of cancer. Omega-3 fatty acids are well known anti-inflammatory dietary supplements. Because inflammation is associated with cancer, Hursting is investigating whether these supplements can reduce risk of developing cancer.
In a recently published report (Ford et al., 2015), Hursting and colleagues asked whether omega-3-fatty acids inhibit tumor growth in a mouse model of breast cancer. This particular study looked at tumors representative of human post-menopausal triple-negative breast cancer (TNBC). TNBC in humans is highly aggressive and associated with higher recurrence and mortality. Notably, the study found that two omega-3 derivatives, EPA and DHA (anti-inflammatories commonly found in fish oil supplements), reduce TNBC tumor growth in obese, but not non-obese, mice. Obesity is a source of systemic inflammation. The finding of differences between obese and non-obese mice suggests it is the anti-inflammatory properties of EPA and DHA that limit tumor growth.
Weight Loss Surgery May Shed Light on New Mechanisms to Slow Breast Cancer Tumor Growth
Weight loss surgery was more effective than a low-fat diet at reversing the cancer-promoting effects of chronic obesity in mice, report UNC Lineberger Comprehensive Cancer Center researchers. The preliminary findings (abstract #2614) will be presented from 1-5 p.m., CST, April 18 at the 2016 American Association of Cancer Research Annual Meeting in New Orleans.
“Our basic finding was that surgical weight loss in obese mice was able to inhibit mammary tumor growth in a mouse model of basal-like breast cancer, while weight loss induced by a low fat, low calorie diet was not,” said Emily Rossi, the paper’s first author and a pre-doctoral trainee with the UNC Lineberger Cancer Control and Education Program. Rossi and her colleagues in the lab of Stephen Hursting, PhD, MPH, a UNC Lineberger member and professor of nutrition in the UNC Gillings School of Global Public Health and the UNC Nutrition Research Institute, are leading research to understand and potentially break the link between obesity and cancer.
“One consequence of the obesity epidemic in the United States and many other countries is increasing rates of obesity-related cancer,” Hursting said. “However, we are not going to solve this growing problem through bariatric surgery, which, despite being effective, is too expensive and too difficult to be done on everyone who is obese. Our goal is to understand what the surgery is doing metabolically to slow tumors, and replicate those protective effects through combinations of diet, exercise and possibly drugs that target some of the same pathways as the bariatric surgery.”
Learn more about cancer prevention research at the NC Research Campus.