Soy and colon cancer [Was: Desirable Protein Intake]

[Guest guest]

Compounds found in soy may help protect the colon. These plant

compounds, sphingolipids, in a May 2004, study appeared to inhibit

the formation and growth of colon tumors.

Another item to add your list, Rodney?

http://snipurl.com/7t3h

J Nutr. 2004 May;134(5):1157-61. Related Articles, Links

Dietary soy sphingolipids suppress tumorigenesis and gene expression

in

1,2-dimethylhydrazine-treated CF1 mice and ApcMin/+ mice.

Symolon H, Schmelz EM, Dillehay DL, Merrill AH Jr.

Program in Nutrition and Health Science, Emory University, Atlanta,

GA

30322, USA.

Dietary supplementation with milk sphingolipids inhibits colon

tumorigenesis

in CF1 mice treated with a colon carcinogen [1,2-dimethylhydrazine

(DMH)]

and in multiple intestinal neoplasia (Min) mice, which develop

intestinal

tumors spontaneously. Plant sphingolipids differ structurally from

those of

mammals [soy glucosylceramide (GlcCer) consists predominantly of a

4,8-sphingadiene backbone and alpha-hydroxy-palmitic acid], which

might

affect their bioactivity. Soy GlcCer was added to the AIN-76A diet

(which

contains <0.005% sphingolipid) to investigate whether it would also

suppress

tumorigenesis in these mouse models. Soy GlcCer reduced colonic cell

proliferation in the upper half of the crypts in mice treated with

DMH by 50

and 56% (P < 0.05) at 0.025 and 0.1% of the diet (wt/wt),

respectively, and

reduced the number of aberrant colonic crypt foci (an early marker

of colon

carcinogenesis) by 38 and 52% (P < 0.05). Min mice fed diets

containing

0.025 and 0.1% (wt/wt) soy GlcCer developed 22 and 37% fewer

adenomas (P <

0.05), respectively. The effects of dietary sphingolipids on gene

expression

in the intestinal mucosal cells of Min mice were analyzed using

Affymetrix

GeneChip microarrays. Soy GlcCer affected the expression of 96 genes

by > or

= 2-fold in a dose-dependent manner, increasing 32 and decreasing

64.

Decreases in the mRNA expression of two transcription factors

associated

with cancer, hypoxia-induced factor 1 alpha (HIF1 alpha) and

transcription

factor 4 (TCF4), were confirmed by quantitative RT-PCR. In

conclusion, soy

GlcCer suppressed colon tumorigenesis in two mouse models; hence,

plant

sphingolipids warrant further investigation as inhibitors of colon

cancer.

Because soy contains relatively high amounts of GlcCer,

sphingolipids may

partially account for the anticancer benefits attributed to soy-

based foods.

PMID: 15113963 [PubMed - indexed for MEDLINE]

+++++++++++++++++++++++++++++++++++++++++++++++

> BUT soy ***protein*** does not contain ALA. So if there truly are

> benefits to soybeans perhaps they are from the protein component?

>

> I go out of my way to avoid soybeans, tofu, soybean oil, etc., but

I

> am happy to eat soy protein if it is served to me. fwiw.

>

> Rodney.

===============================================

Take: statins, vitamin E & tocotrienols, calcium (???), coffee,

copper, exercise, cruciferous vegetables, garlic, vitamin D,

turmeric, zinc, tea, selenium, resveratrol (and other COX-2

inhibitors like rosemary and red grapes), CR, vitamin C (?), aspirin,

EPA & DHA, vitamin A, citrus pectin, insoluble fiber, colonoscopy.

Also take folic acid, it reduces incidence by a huge 75% but only

after 15 years of supplementing .............

Avoid: living at a higher latitude, eating red meat, smoking, being

over weight, diabetes, *excessive* alcohol cunsumption.

Rodney.