Differential modulation by dietary n-6 or n-9 unsaturated fatty acids on the developoment of two murine mammary gland tumors having different metastatic capabilities

MUÑOZ, SE; LOPEZ, CB; VALENTICH, MA; EYNARD, AR

CANCER LETTERS

Elsevier Science Ireland.Ltd.

Año: 1998 vol. 126 p. 149 - 155

0304-3835

It is widely known that dietary lipids can modify the ability of different cancers to grow up and metastasize, especially mammary gland tumors. However, it is still unclear whether n-6 fatty acids behave as tumo¡ promoters in this gland cell population. The effect of different nutritional polyunsaturated fatty acids (PUFAs) on tumor growth parameters of two transplantable murine mammary gland adenocarcinomas of low and high metastatic ability was tested on hosts fed diets with corn oil (CO) rich tn 782n-6, evening primrose oil (EPO) containing 18:3n-6 (GLA) and a rhird formula supplemented with olein (O) 18: 1n-9, which induces an essential fatty acid deficiency (EFAD). Tumor growth parameters were not adversely affected in the co¡n oil group with respect to stock-fed controls. Furthermore, metastatic spreading diminished in this group. EPO showed a moderate antitumor activity whereas the n-9-enriched diet showed no clear-cut effects. In both mammary gland tumors, n-6 fatfy acid-rich lipids formulae, containing GLA and iinoleic acid, were not tumor promoters. On the contrary, both exhibited anticancer activity.