Flaxseed inhibits breast cancer in animal model

Dietary flaxseed and its components inhibit the progression of estrogen receptor-negative human breast cancer xenografts in mice, Canadian researchers report in the September issue of the International Journal of Cancer.

“Although the study still needs confirmation in clinical trials, our findings suggest that a dietary regimen including flaxseed with its lignan and oil components has the potential to improve the survival of women with estrogen receptor-negative breast cancer by reducing the tumor growth and metastasis,” senior investigator Dr. Lilian U. Thompson told Reuters Health.Dr. Thompson and colleagues at the University of Toronto studied athymic nude mice with breast cancer xenografts that were fed a diet supplemented with flaxseed, flaxseed oil alone, lignan alone, or a combination of oil and lignan.Compared with control mice fed a standard diet without these components, tumor growth was significantly reduced. Cell proliferation was inhibited and apoptosis was increased. The researchers note that lipid peroxidation did not appear to be the main mechanism behind tumor growth reduction.Lung metastasis was reduced by all treatments, significantly so in the flaxseed and the lignan with oil groups. Distant lymph node metastases were significantly reduced only in the oil with lignan group. However, the differences across groups were not significant.At a 10% dietary level, flaxseed caused no untoward effects in the mice, “suggesting that it may be safe for the treatment of estrogen-independent breast cancer.”(Source: Int J Cancer 2005;116:793-798: Reuters Health: Oncolink: October 2005.)