Abstract 2877: TRAMP-injected mice fed a no-carbohydrate ketogenic diet demonstrate prolonged survival and decreased tumor volumes compared to mice fed western or low-fat diets

Introduction and Objective: In multiple previous studies, we have shown that mice injected with subcutaneous prostate cancer cells (LNCaP or LAPC-4) and fed a no-carbohydrate ketogenic diet (NCKD, 84% fat, 0% carbohydrate, 16% protein) have significantly decreased tumor volume and significantly prolonged survival, compared to mice fed a western diet (WD, 40% fat, 44% carbohydrate, 16% protein). All previous studies utilized a human prostate cancer cell line, requiring the use of immunodeficient mice. We sought to replicate these previous studies to determine whether diet affected tumor progression and survival in an immunocompetent model.

Methods: In this treatment model, 75 male C57bl/6 mice were initially fed WD ad libitum for a period of 14 days. After this 14 day period, all mice were injected subcutaneously with 2.5×10⁵ TRAMP cells and randomized to one of three diets: WD, NCKD, or low-fat diet (LF, 12% fat, 72% carbohydrate, 16% protein). Mice receiving LF diet were fed ad libitum, and served as the reference group in paired-feeding protocols for mice receiving WD and NCKD. Tumor volumes were assessed twice weekly, and mice were sacrificed when tumor volumes reached 1000mm³. Survival was calculated using a Log-rank test and tumor volumes were compared among dietary groups using Kruskal-Wallis test for significance.

Results: Mice fed a NCKD demonstrated a trend towards decreased tumor volumes compared to mice fed WD and LF. Median tumor volume at study day 66 for mice fed WD, LF, and NCKD were 1091.2 mm³, 1082.9 mm³, and 661.5mm³ respectively. While the tumor volumes were smaller in mice fed NCKD versus LF or WD, these differences did not reach statistical significance (WD vs. NCKD, p=0.06; LF vs. NCKD, p=0.12). There was no significant difference between tumor volumes among mice fed WD compared to LF (p=0.95). Additionally, a trend towards improved survival was seen in mice fed NCKD vs. WD (p=0.09).

Conclusion: This study in an immunocompetent xenograft model supports the findings of multiple previous studies. Mice fed a NCKD demonstrated a trend towards prolonged survival and decreased tumor volume compared to mice fed WD.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2877.