Re: Dietary omega-3 polyunsaturated fatty acids promote colon carcinoma metastasis

[Guest guest]

Well, I don't eat much fish, but the test is with rats, not humans, and the rats are bred to get cancer, as I recall. The cancer cells are inserted, suggesting they think human cancer is acquired in that manner. That may be partly true for metastases, but I don't think that's how cancer starts in a human. Certainly later it can metastasize.

Based on the fact that millions of humans that eat a lot of fish are not dying, I'd wouldn't be afraid to eat fish or take fish oil.

Another question is how much fish oil were they fed, and what would that equate to in a human?

Also, looking at the conclusion, it may very well have serious implications for those with cancer. Do we omit fish/oil because we fear there might be a carcinoma cell in there somewhere?

Recognize it is possible to eat a little PUFA for essentials without calling it a diet.

Finally, see if you can find concurrence in a later than 1998 article.

This one PMID: 16771072, May 2006, condemns n-6 and sat fat, promoting n-3.

Regards.

[ ] Dietary omega-3 polyunsaturated fatty acids promote colon carcinoma metastasis

I haven't seen this association before so I was taken aback by this!"Rats were kept on either a low-fat diet or on a fish oil (omega-3PUFAs) or safflower oil (omega-6 PUFAs) diet for 3 weeks before theadministration of colon cancer cells to the portal vein, until theywere sacrificed at 1 or 3 weeks after tumor transplantation. At 1 weekafter transplantation, the fish oil diet had induced 7-fold moremetastases (in terms of number and size) than had the low-fat diet..."What do you "fish advocates" make of this? I don't each much fish, nowi am glad i haven't, my diet is predominately plant-based. Prior tothis discovery, I have considered eating more, but not now.Cancer Res. 1998 Aug 1;58(15):3312-9. Related Articles, LinksDietary omega-3 polyunsaturated fatty acids promote coloncarcinoma metastasis in rat liver.i P, Fehres O, Klieverik L, Vogels IM, Tigchelaar W,Smorenburg SM, Van Noorden CJ.Academic Medical Center, University of Amsterdam, Department ofCell Biology and Histology, The Netherlands.The effects of omega-3 polyunsaturated fatty acids (PUFAs) andomega-6 PUFAs on the development of experimentally induced coloncarcinoma metastasis in rat liver were investigated quantitatively invivo. Rats were kept on either a low-fat diet or on a fish oil(omega-3 PUFAs) or safflower oil (omega-6 PUFAs) diet for 3 weeksbefore the administration of colon cancer cells to the portal vein,until they were sacrificed at 1 or 3 weeks after tumortransplantation. At 1 week after transplantation, the fish oil diethad induced 7-fold more metastases (in terms of number and size) thanhad the low-fat diet, whereas the safflower oil diet had not affectedthe number and total volume of metastases. At 3 weeks after tumortransplantation, the fish oil diet and the safflower oil diet hadinduced, respectively, 10- and 4-fold more metastases (number) andover 1000- and 500-fold more metastases (size) than were found in thelivers of rats on the low-fat diet. These differences were sexindependent. Immunohistochemical analysis revealed that the immunesystem in the liver (Kupffer cells, pit cells, T cells, newlyrecruited macrophages, and the activation state of macrophages) didnot play a significant role in this diet-dependent outgrowth oftumors. In conclusion, omega-3 and omega-6 PUFAs promote colon cancermetastasis in the liver without down-regulating the immune system.This finding has serious implications for the treatment of cancerpatients with fish oil diet to fight cachexia.PMID: 9699661

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[Guest guest]

The age of this article is 1998 or an eternity in terms of nutritional science. There have been dozens of studies since then promoting the health benefits of fish and fish oil. Now if you were to come up with a RECENT study such as this, it might be worth taking note of, but the old age of this one renders it almost meaningless......

on 7/8/2006 3:49 PM, bill4cr at bill4cr@... wrote:

I haven't seen this association before so I was taken aback by this!

" Rats were kept on either a low-fat diet or on a fish oil (omega-3

PUFAs) or safflower oil (omega-6 PUFAs) diet for 3 weeks before the

administration of colon ......(snippped)

Cancer Res. 1998 Aug 1;58(15):3312-9. Related Articles, Links