Prebiotic/Probiotic Combination Affects Tumor Formation in a Rat Model of Breast Cancer

A combination of Lactobacillus plantarum and a modified inulin derivative reduced expression of T-cells in mammary cancers induced in rats.

Researchers Kassayová and colleagues at the International Institute of Anticancer Research recently published a study in the journal Anticancer Research on the effect of a probiotic bacteria and dietary fiber intake on reducing the risk of breast cancer in a rat model with chemically induced breast cancer.¹

Daily oral administration of probiotic bacteria Lactobacillus plantarum LS/07 840 million colony-forming units daily and a prebiotic (oligofructose-enriched inulin 20 grams daily) was initiated 2 weeks before chemical exposure. After 2 weeks of treatment with the investigational combination, the rats were dosed with 7, 12-dimethylbenz[a]anthracene (DMBA), a compound that is known to induce mammary carcinogenesis.¹

Over the remaining 14 weeks of the experiment, researchers observed immunologic changes in tissue and a significantly lower risk of breast cancer in rats treated with the probiotic/prebiotic combination treatment than in rats receiving a control preparation. T-cell levels were elevated in rats receiving the prebiotic/probiotic combination treatment, which points to a possible mechanism for this protective effect.

With treatment, levels of a proinflammatory cytokine—serum tumor necrosis factor-α—were suppressed, suggesting an immunomodulatory effect of the intervention.¹

Probiotic/probiotic compounds are commonly available in dietary supplements and are used for a variety of conditions, including protection of the gastrointestinal tract from opportunistic infection and as a preventive for traveler's diarrhea.¹

Researchers have been working on immunonutrition as a mechanism for prevention of cancer for many years. In 1998, researchers observed a strong protective effect of prebiotic fibers on gastrointestinal tissues.

Researchers have also posited that Lactobacillus plantarum, which is used in many traditional cultures as a method of preventing food spoilage, may reduce the risk of exposure to immune system-damaging compounds present in foods. Lactobacillus plantarum also aids in nitrate elimination, nitric oxide formation, and augments the integrity of the gastrointestinal mucosa.²

Previous studies have shown the preventive effect of probiotics in rat models of colon cancer. These new data show that the effects of prebiotics and probiotics may extend to other types of cancer, as well.^3-5

These emerging animal data may spur further research into probiotics as a preventive measure in human cancers. However, it is important to remember that these very preliminary data are insufficient to recommend probiotics or prebiotics as a treatment option for any patients with breast cancer, or patients at risk for breast cancer or any other type of cancer.¹

References:

• Kassayová M, Bobrov N, Strojný L, et al. Preventive Effects of Probiotic Bacteria Lactobacillus plantarum and Dietary Fiber in Chemically-induced Mammary Carcinogenesis. Anticancer Res.2014;34(9):4969-4975.
• Bengmark S. Immunonutrition: role of biosurfactants, fiber, and probiotic bacteria. Nutrition. 1998;14(7-8):585-8):585-94.
• Reddy BS. Possible mechanisms by which pro- and prebiotics influence colon carcinogenesis and tumor growth. J Nutr. 1999;129(7 Suppl):1478-182S.
• Femia AP, Luceri C, Dolara P, et al. Antitumorigenic activity of the prebiotic inulin enriched with oligofructose in combination with the probiotics Lactobacillus rhamnosus and Bifidobacterium lactis on azoxymethane-induced colon carcinogenesis in rats. Carcinogenesis. 2002;23(11):1953-1960.
• Bertkova I, Hijova E, Chmelarova A, et al. The effect of probiotic microorganisms and bioactive compounds on chemically induced carcinogenesis in rats. Neoplasma. 2010;57(5):422-428.