The rate of APC mutations in the intestine increases in middle-age. At
the same period of life, plant sterol and stanol enriched functional
foods are introduced to diet to lower blood cholesterol. This study
examined the effect of plant stanol enriched diet on intestinal adenoma
formation in the Apc(Min) mouse. Apc(Min) mice were fed 0.8% plant
stanol diet or control diet for nine weeks. Cholesterol, plant sterols
and plant stanols were analyzed from the caecum content and the
intestinal mucosa. Levels of β-catenin, cyclin D1, epidermal growth
factor receptor (EGFR) and extracellular signal-regulated kinase 1/2
(ERK1/2) were measured from the intestinal mucosa by Western blotting.
Gene expression was determined from the intestinal mucosa using
Affymetrix and the data were analyzed for enriched categories and
pathways. Plant stanols induced adenoma formation in the small
intestine, however, the adenoma size was not affected. We saw increased
levels of nuclear β-catenin, phosphorylated β-catenin (Ser675 and
Ser552), nuclear cyclin D1, total and phosphorylated EGFR and
phosphorylated ERK1/2 in the intestinal mucosa after plant stanol
feeding. The Affymetrix data demonstrate that several enzymes of
cholesterol synthesis pathway were up-regulated, although the
cholesterol level in the intestinal mucosa was not altered. We show that
plant stanols induce adenoma formation by activating Wnt and EGFR
signaling. EGFR signaling seems to have promoted β-catenin
phosphorylation and its translocation into the nucleus, where the
expression of cyclin D1 was increased. Up-regulated cholesterol
synthesis may partly explain the increased EGFR signaling in the plant
stanol-fed mice.
Link to the above article here.
An adenoma is a benign tumor (-oma) of glandular origin. Adenomas can grow from many organs including the colon, adrenal glands, pituitary gland, thyroid, prostate, etc. Although these growths are benign, over time they may progress to become malignant, at which point they are called adenocarcinomas. Even while benign, they have the potential to cause serious health complications by compressing other structures (mass effect) and by producing large amounts of hormones in an unregulated, non-feedback-dependent manner (paraneoplastic syndrome).
Wiki link here.
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