(P13-013-23) A Low Carbohydrate Diet High in Soy Protein and Fish Oil Reduces Lung, Breast, Myelodysplastic and Colon Cancer in Mouse Models

Objectives: Based on Otto Warburg's observation that cancer cells typically consume more glucose than normal cells, we hypothesized that a low carbohydrate diet might be effective in slowing tumor growth. Since a diet low in carbohydrate typically contains higher fat and/or protein levels, and the protein or fat types may influence cancer progression, we evaluated the efficacy of different types of low carbohydrate diets in preventing tumor formation in a number of mouse models.

Methods: We first compared the effect of varying the level and type of carbohydrate, protein and fat within mouse chows on lung tumor formation in tobacco carcinogen-injected A/J mice. Since no two cancer types are the same, the diet shown to be most effective in reducing lung tumor nodules was then evaluated against a Western diet in other cancer models. Specifically, we used the  low carbohydrate diet that was most effective at reducing lung cancer to assess its efficacy in reducing breast and prostate cancer in transgenic C3(1)/Tag mice, in reducing colon cancer in azoxymethane/dextran sodium sulfate (AOM/DSS)-treated Balb/C mice and in reducing myelodysplasia in miR-146aKO mice.

Results: A diet containing amylose as a source of carbohydrate (at 15% of total calories), soy protein (at 35%) and fat (at 50%, 30% being fish oil) was the most effective at reducing tobacco carcinogen-induced lung nodules in A/J mice. This low carbohydrate diet (15%Amylose/Soy/FO) also significantly (P < 0.05) reduced colorectal tumor formation in AOM/DSS-treated Balb/C mice when compared to a Western diet. When fed to the C3(1)/Tag transgenic mice, which spontaneously develop prostate and breast cancer, this low carbohydrate diet significantly reduced (P < 0.05) mammary tumor burden in the female mice, but had no impact on the number of prostate lesions in the male mice. Tested in miR-146aKO mice, the 15%Amylose/Soy/FO significantly (P < 0.05) delayed myelomalignancies, which, in turn, extended the lifespan of these mice.

Conclusions: Taken together, this demonstrates that, compared to a Western diet, a low carbohydrate diet composed of 15% of total calories as the resistant starch, amylose, 35% as soy protein and 50% as fish oil-enriched fat was effective in slowing myelodyplasia, as well as lung, breast and colon cancer, but not prostate cancer in mice.

Funding Sources: This work was funded by Hecht Grant #4340 to GK.