Protective capability of dietary Zizyphus mistol seed oil, rich in 18:3, n-3, on the development of two murine mammary gland adenocarcinomas with high or low metastatic potential.

The modulating effect of dietary Zizyphus mistol seed oil, rich in the n-3 polyunsaturated fatty acid alpha-linolenic acid, on two murine mammary gland adenocarcinomas having low (M2) and high (MM3) metastatic abilities was investigated. Following tumor subcutaneous inoculation, 165 BALB/c mice were fed on a semisynthetic diet containing 5% of mistol oil which has 25% of 18:3, n-3 (mistol group). The other group received a stock diet (C group). Tumor growth parameters such as success of tumor implants (ST), latency time (LT), tumor growth (TG), tumor volume (TV), survival, and number and sites of metastases were recorded. Fatty acid profiles of liver lipids correlated well with dietary fatty acids, with a n-3/n-6 ratio of 0.90:1 in the mistol group against 0.24:1 in the C group. None of the tumor growth parameters were worse in the mistol group with respect to the controls. On the contrary, survival in M2 hosts and tumor weight in MM3-bearing mice were significantly ameliorated. A tendency towards a diminution of total number of metastases in both types of tumor was observed in the mistol group. From these results, it is suggested that Z. mistol seed oil may be of potential value in nutritional oncology.