Dietary n-6 @entity1474 ( @entity5204 ) promote @entity35 mammary @entity5 while n-3 @entity5204 are inhibitory. The purpose of this study was to determine whether the fats exert their effects by altering the expression of genes that affect @entity5 development. Therefore, we have examined the effect of @entity5204 on the expression of the @entity9773 genes that are involved in @entity3009 biosynthesis. We also investigated the effect of dietary @entity5204 on the expression of the @entity3803 protein and Ha-ras mRNA. @entity35 were fed either low- (7%; LF) or high- (21%; HF) fat diets that were rich in either n-6 @entity5204 (safflower oil, S) or n-3 @entity5204 (menhaden oil, M) for 3 weeks. @entity9774 mRNA levels were approximately the same in groups fed diets containing either level of menhaden oil, but were increased by approximately 30% in the LFS and HFS groups (P < 0.05). Transcripts of the inducible @entity4665 gene were not detectable in the menhaden oil groups, but this gene was expressed in animals fed either level of safflower oil and in the HFS group was associated with increased levels of COX enzymatic activity and production of @entity1421 . Animals fed safflower oil had elevated levels of @entity3803 protein compared to animals fed menhaden oil. Ha-ras mRNA was increased by approximately 35% in animals fed HFS compared to the group fed @entity4802 (P < 0.05). These results demonstrate that dietary n-6 @entity5204 upregulate @entity4665 and, to some extent, @entity9774 expression. There was a concomitant increase in COX enzyme activity and PG synthesis in the mammary glands of @entity35 fed high levels of n-6 @entity5204 . Together with associated changes in @entity3803 expression, these results may explain, at least in part, the promoting effects of dietary n-6 @entity5204 on mammary carcinogenesis.

The effect of dietary n-3 and n-6 @entity1474 on the expression of cyclooxygenase 1 and 2 and levels of @entity3803 in XXXX mammary glands.

@entity5204 :: ('CHEBI:26208', 'Chemical') :: ['PUFAs'] @entity9773 :: ('24693;29527;26195;26198', 'Gene') :: ['cyclooxygenase (COX) 1 and 2'] @entity4802 :: ('MESH:D006053', 'Disease') :: ['HFM'] @entity5 :: ('MESH:D009369', 'Disease') :: ['cancer'] @entity1421 :: ('MESH:D015232', 'Chemical') :: ['PGE2'] @entity1474 :: ('MESH:D005231', 'Chemical') :: ['polyunsaturated fatty acids'] @entity3009 :: ('CHEBI:26333', 'Chemical') :: ['prostaglandin'] @entity9774 :: ('26195(Tax:10116)', 'Gene') :: ['COX-1'] @entity35 :: ('10116', 'Species') :: ['rat', 'Rats', 'rats'] @entity4665 :: ('26198(Tax:10116)', 'Gene') :: ['COX-2'] @entity3803 :: ('293621(Tax:10116)', 'Gene') :: ['p21ras']
@entity35 :: (10116,Species) :: ['rat']
