Correction: RE Dietary omega-3 pufas promote colon carcinoma metastasis

[Guest guest]

The 2005 study I posted earlier does *not* contradict the colon

carcinoma metastatis study after all. The 2005 study discusses

primary colon cancer, while the 1998 study that Kayce posted addresses

colon cancer metastasis to the liver.

The only other study I could find that addresses the metastasis/omega

3 issue is one that found that the metastases in the liver for rats

fed a high n-3 diet lacked outer stroma (framework). They hypothesize

that this is due to rapid development of tumors in n-3 fed rats. This

is important and hopefully is being investigated further.

Nevertheless, it was an investigation of the tumor-forming

mechanism, not a validation of the 1995 work:

" Promotion of colon cancer metastases in rat liver by fish oil diet is

not due to reduced stroma formation "

http://snipurl.com/t6mp

Diane

>

> Here's a 2005 study that contradicts the 1998 study:

>

>

> Effects of a flaxseed mixture and plant oils rich in alpha-linolenic

> acid on the adenoma formation in multiple intestinal neoplasia (Min)

mice.

>

> Oikarinen SI, Pajari AM, Salminen I, Heinonen SM, Adlercreutz H,

> Mutanen M.

>

> Department of Applied Chemistry and Microbiology (Nutrition), PO Box

> 66, FIN-00014 University of Helsinki, Finland. seija.oikarinen@...

>

> Flaxseed is a dietary source of possible chemopreventive compounds

> such as lignans and alpha-linolenic acid (ALA). To study the effects

> of a flaxseed mixture on adenoma formation in multiple intestinal

> neoplasia mice, the mice were fed a diet containing 2.7 % flaxseed,

> 4.5 % fibre and 3.7 % ALA. To elucidate the effect of oils of the

> mixture we also composed a diet without flaxseed but with the same oil

> composition. The median number of adenomas in the small intestine was

> fifty-four for the control group, and thirty-seven (P=0.023) and

> forty-two (P=0.095) for flaxseed and oil groups, respectively.

> Compared with controls (1.2 mm), the adenoma size was smaller in the

> flaxseed (0.9 mm; P=0.002) and oil (1.0 mm; P=0.012) groups. Both

> diets changed the proportions of n-3 and n-6 fatty acids in the

> colonic mucosa. Membrane beta-catenin and protein kinase C (PKC)-zeta

> levels were reduced in the adenoma v. mucosa (P<0.05), and an inverse

> association was found between the membrane PKC-zeta in the mucosa and

> the adenoma number (r -0.460, P=0.008, n 32). Only the flaxseed diet

> increased lignan levels in the caecum (P=0.002) and in plasma

> (P=0.002) but they were not associated with tumour formation. The

> results suggest that the preventive effect of flaxseed on colon

> carcinogenesis may be due to the oil part of flaxseed, and the loss of

> beta-catenin and PKC-zeta from the membranes of the mucosal tissue may

> play a permissive role in intestinal tumour development.

>

> PMID: 16197574 [PubMed - indexed for MEDLINE]

>

>

> http://snipurl.com/t6kr

>