Diets high in cholesterol and fat fuel the growth and spread of breast cancer, suggests a mouse study.
Researchers at the Kimmel Cancer Center at Jefferson determined how the American diet that high in fat and cholesterol makes cancer tumors grow and spread faster, in a mouse study.
Philippe G. Frank, Ph.D., Assistant Professor in the Department of Stem Cell Biology and Regenerative Medicine at Thomas Jefferson University found breast cancer tumors use cholesterol as building blocks to grow, making them more aggressive.
He explains how cancerous tumors use cholesterol once it enters the bloodstream: “In a neighborhood, if you want to build more houses, you need more bricks. In tumors, cholesterol provides the bricks that are the foundation for further growth, and this cholesterol comes from the blood. A drop in blood cholesterol may signify that some tumors are growing as cholesterol provides support for breast cancer growth.”
To find the link between diet and breast cancer, Frank’s team used the PyMT mouse model. One group of mice was fed a diet consisting of 21.2 percent fat and 0.2 percent cholesterol, contained in a typical American diet. A control group of the genetically engineered mice was given a diet with 4.5 percent fat and negligible amounts of cholesterol.
The mice used in the study are genetically engineered to be susceptible to breast cancer. The group given a high fat, high cholesterol diet developed breast cancer tumors quickly that were 50 percent larger and double the amount of the mice given a normal diet. The tumors also were more likely to metastasize to the lungs, the researchers found.
Dr. Frank says, “Cholesterol does indeed seem to be an important factor in the regulation of tumor formation in several cancer types.” A study published in December 2010 found the same association between prostate cancer cholesterol and prostate cancer growth, published in the American Journal of Pathology.
The scientists measured several biomarkers showing more advanced stages of cancer in the mice given the typical American diet, confirming that cholesterol and fat in the made breast cancer more aggressive. Studies also link a fatty diet to development of pancreatic cancer.
Cholesterol levels in the bloodstream were significantly lower in the experimental mice compared to “wild” animals, something Dr. Frank says, …"suggests that tumor formation was responsible for the reduction in blood cholesterol levels observed in our animals."
The findings mean measuring blood cholesterol levels could serve as a tool for screening. Dr. Frank also suggests statins that lower cholesterol might protect women from developing breast cancer. The results of the two recent studies show a high cholesterol, high fat diet contributes to breast cancer and prostate cancer, and are important for disease prevention strategies.