Researchers from The University of Texas MD Anderson Cancer Center have found that high amounts of sugar, characteristic of the typical Western diet, could increase the risk of breast cancer.
Studying the effect of dietary sugar on the enzymatic signaling pathway called 12-LOX or 12-lipoxygenase, the researchers said their results suggested that dietary sugar causes a 12-LOX signaling pathway to increase breast cancer risk, induce tumor growth and make it to spread to the lungs.
The researchers conducted a study involving mice that were divided into four groups, each group fed with a specific diet. After six months, 50 to 58 percent of mice that were given sucrose-rich diets grew tumors in the mammary gland.
"We found that sucrose intake in mice comparable to levels of Western diets led to increased tumor growth and metastasis, when compared to a non-sugar starch diet," Peiying Yang, study author and assistant professor of Palliative, Rehabilitation and Integrative Medicine, said in a news release. "This was due, in part, to increased expression of 12-LOX and a related fatty acid called 12-HETE."
The findings also showed that mice fed with a high sucrose or high fructose diet that developed mammary tumors were more likely to experience metastasis to the lungs compared to those fed with starch-control diet.
"We determined that it was specifically fructose, in table sugar and high-fructose corn syrup, ubiquitous within our food system, which was responsible for facilitating lung metastasis and 12-HETE production in breast tumors," study co-author Lorenzo Cohen said.
The researchers said that the effect of dietary sugar on the 12-LOX pathway and breast cancer growth should be investigated further. They also emphasized the importance of moderate sugar consumption, especially with sugar consumption in the U.S. rising to 100 pounds every year and previous studies identifying sugary drinks as a major factor in the growing epidemic obesity.
The study was published in the Jan. 1 online issue of the journal Cancer Research.
