Site brasileiro onde você pode comprar qualidade e entrega viagra preço cialis barato em todo o mundo.
Microsoft word - dietnews_feb-2008_flax-inhibitstumo.doc
Flax and Its Mammalian Lignans Inhibit Tumour Angiogenesis in Mice
by Diane H. Morris
In a recent mouse study, flax and its mammalian lignans, enterodiol and
enterolactone, exerted potent antiestrogenic effects on estrogen receptor-positive (ER+) breast cancer by inhibiting tumour growth and angiogenesis.1 Angiogenesis –
the formation of new blood vessels – is an essential step in tumour development and metastasis. A tumour’s ability to form new blood vessels depends on a delicate
balance of factors that promote or inhibit angiogenesis. One potent promoter of angiogenesis is vascular endothelial growth factor (VEGF).2 High tumour levels of VEGF have been associated with a poor prognosis and decreased survival among
Using both in vitro
and in vivo
methods, Jungeström and colleagues at the
University Hospital in Linköpling, Sweden and the University of Toronto in Canada reported that milled flax, enterodiol and enterolactone counteract the tumour
growth-promoting effects of estradiol and decrease both angiogenesis and VEGF secretion.1 The main lignan in flax, secoisolariciresinol diglucoside (SDG), is
converted to the mammalian lignans enterodiol and enterolactone by gut bacteria.3 The
model mimicked breast cancer in premenopausal women by
maintaining a stable background level of estrogen. For the in vivo
study, nude mice
were implanted with estradiol pellets, injected with MCF-7 cells and fed a basal diet until tumours formed. When tumours reached a size of ∼30 mm2, one group
continued the basal diet (control group), one group started a 10% milled flax diet,
one group started with daily injections of enterodiol, and one group started with daily injections of enterolactone. Final tumour weights were significantly lower in the milled flax, enterodiol and enterolactone groups compared with the control group. VEGF secreted by tumours decreased by ∼50% and angiogenesis decreased by ∼60-
80% in the treatment groups compared with the control group.
This study shows that milled flax and its mammalian lignans can inhibit tumour
growth through their actions on estradiol and angiogenesis in ER+ breast cancer in vivo
. The flax and mammalian lignans acted by blocking two actions of estradiol – its
ability to increase the expression (activation) of VEGF receptor 2 and also its ability to increase VEGF secretion. The flax and mammalian lignans reduced VEGF receptor 2 expression and decreased VEGF secretion, while also inhibiting angiogenesis and
tumour growth, all without exhibiting estrogen-like actions themselves. These findings suggest ways in which flax and its lignans may help prevent ER+ breast
cancer in humans. References
1. Jungeström MB, Thompson LU, Dabrosin C. 2007. Flaxseed and its lignans inhibit
estradiol-induced growth, angiogenesis, and secretion of vascular endothelial growth factor in human breast cancer xenografts in vivo. Clin. Cancer Res. 13: 1061-1067.
2. Bockhorn M, Jain RK, Munn LL. 2007. Active versus passive mechanisms in metastasis: do
cancer cells crawl into vessels, or are they pushed? (essay) Lancet Oncol. 8: 444-448.
3. Flax Council of Canada. 2007. Backgrounder on lignans. In: Flax – A Health and Nutrition
, 2nd ed. Available at www.flaxcouncil.ca.
Flax Council of Canada – February 2008
POSTAL ADDRESS HEAD OFFICE IMPORTANT - PLEASE READ CAREFULLY Please list receipts for all medical costs and ALL PRESCRIPTION CHARGES INDIVIDUALLY, below. “Consultation” or “check up” is NOT sufficient for the “Reason for Visit” section (this information is for auditand planning purposes and helps ensure that benefits are kept current). CLAIMS FORM All claims cheques are pa
Lugares donde puedes hacer ecoturismo en lasUna manera de disfrutar las vacacaciones es hacer ecoturismo, pero ésta actividadimplica muchas más cosas que simplemente visitar atracciones naturales. Descubre 12lugares en el mundo donde puedes hacer ecoturismo en las vacaciones. También te puede interesar: El ecoturismo es una tendencia cada vez más fuerte entre los turistas Lugar