“The molecular mechanisms behind the obesity-breast cancer association may be regulated via adipokine secretion by white adipose tissue. Specifically, adiponectin and leptin are altered with adiposity and exert antagonistic effects on cancer cell proliferation.”
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“We set out to determine whether altering adiposity in vivo via high fat diet feeding changed the tumor growth supporting nature of adipose tissue and whether voluntary physical activity could ameliorate these high fat diet-dependent effects.”
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“We show that conditioned media created from the adipose tissue of high fat diet fed animals caused an increase in the proliferation of MCF7 cells compared with cells exposed to conditioned media prepared from the adipose of lean chow diet fed counterparts.”

“This increased proliferation was driven within the MCF7 cells by an high fat diet-dependent antagonism between AMP-activated protein kinase and protein kinase B signaling pathways, decreasing p27 protein levels via reduced phosphorylation at T198 and downregulation of adiponectin receptor 1.”
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“Physical activity can ameliorate these proliferative effects of high fat diet-conditioned media on MCF7 cells, increasing p27T198 by AMPK, reducing pAktT308, and increasing AdipoR1, resulting in cell cycle withdrawal in a manner that depends on the physical activity intensity. High physical activity (>3 km/day) completely abolished the effects of high fat diet feeding.”

“In addition, AdipoR1 overexpression mimics the effects of exercise, abolishing the proliferative effects of the high fat diet-conditioned media on MCF7 cells and further enhancing the antiproliferative effects of physical activity on the high fat diet-conditioned media.”
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“Thus voluntary physical activity represents a means to counteract the proliferative effects of adipose tissue on breast cancers in obese patients.”
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C.F. Theriau, et al
Voluntary physical activity abolishes the proliferative tumor growth microenvironment created by adipose tissue in animals fed a high fat diet
Journal of Applied Physiology — Volume 121 #1 — July 2016 — page 139