[R.B.]

A bit complicated but yet more evidence of the involvement of Omega 6 in breast cancers.

D6D is one of the enzymes that convert plant based Omega 6 (LA) and plant based Omega 3 to the longer fats of the same respective families. The amount of Omega 3 or 6 stored in cell membranes ready for conversion by these enzymes is proportional to the dietary intake.

AA is a longer chain Omega 6.

PGE2 is an oxidized from of AA.

So it is possible to change the processes that take place in these pathways though the choice of dietary intakes of fats.

As often discussed in general on a population wide basis we eat far to much plant based Omega 6 (50% to 70% of many vegetable oils), and too little Omega 3 both plant based and long chain including EPA and DHA, which are not found in many food in quantity. etc etc.



Cancer Sci. 2013 Jun;104(6):760-4. doi: 10.1111/cas.12129. Epub 2013 Mar 19.
Delta-6-desaturase activity and arachidonic acid synthesis are increased in human breast cancer tissue.
Pender-Cudlip MC, Krag KJ, Martini D, Yu J, Guidi A, Skinner SS, Zhang Y, Qu X, He C, Xu Y, Qian SY, Kang JX.
Source

Laboratory for Lipid Medicine and Technology, Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
Abstract

Omega-6 (n-6) arachidonic acid (AA) and its pro-inflammatory metabolites, including prostaglandin E2 (PGE(2)), are known to promote tumorigenesis. Delta-6 desaturase (D6D) is the rate-limiting enzyme for converting n-6 linoleic acid (LA) to AA. Our objective was to determine if AA synthesis, specifically D6D activity, and PGE(2) levels are increased in cancerous breast tissue, and whether these variables differ between estrogen receptor positive (ER+) and negative (ER-) breast cancers. Gas chromatography was performed on surgical breast tissue samples collected from 69 women with breast cancer. Fifty-four had ER+ breast cancer, and 15 had ER- breast cancer. Liquid chromatography-mass spectrometry was used to determine PGE(2) levels. Lipid analysis revealed higher levels of LA metabolites (C18:3 n-6, C20:3 n-6, and AA) in cancerous tissue than in adjacent noncancerous tissue (P < 0.01). The ratio of LA metabolites to LA, a measure of D6D activity, was increased in cancerous tissue, suggesting greater conversion of LA to AA (P < 0.001), and was higher in ER- than in ER+ patients, indicating genotype-related trends. Similarly, PGE(2) levels were increased in cancerous tissue, particularly in ER- patients. The results showed that the endogenous AA synthetic pathway, D6D activity, and PGE(2) levels are increased in breast tumors, particularly those of the ER- genotype. These findings suggest that the AA synthetic pathway and the D6D enzyme in particular may be involved in the pathogenesis of breast cancer. The development of drugs and nutritional interventions to alter this pathway may provide new strategies for breast cancer prevention and treatment.

OR eat much less Omega 6 and more Omega 3, a whole food diet that has not been de-mineralised and oxidised in storage and processing etc . . . but to give this advice would not be very helpful if your future career depended on securing future funding for drugs research. . . there has to be a better way of looking at health provision, a market that is more aware that we all share a very small precious planet, and will need to be at our best to have any hope of keeping it that way, that allows researchers to both secure research funding to expand important knowledge and give optimal health advice !