Exogenous estrogen protects mice from the consequences of obesity and alcohol.
OBJECTIVE
Breast cancer is the second leading cause of cancer death among American women. Risk factors for breast cancer include obesity, alcohol consumption, and estrogen therapy. In the present studies, we determine the simultaneous effects of these three risk factors on wingless int (Wnt)-1 mammary tumor growth.


METHODS
Ovariectomized female mice were fed diets to induce different body weights (calorie restricted, low fat, high fat), provided water or 20% alcohol, implanted with placebo or estrogen pellets and injected with Wnt-1 mouse mammary cancer cells.


RESULTS
Our results show that obesity promoted the growth of Wnt-1 tumors and induced fatty liver. Tumors tended to be larger in alcohol-consuming mice and alcohol exacerbated fatty liver in obese mice. Estrogen treatment promoted weight loss in obese mice, which was associated with the suppression of tumor growth and fatty liver.


CONCLUSIONS
In summary, we show that estrogen protects against obesity, which is associated with the inhibition of fatty liver and tumor growth.
Department of Nutritional Sciences, School of Human Ecology, College of Natural Sciences, The University of Texas at Austin, Austin, TX 78712, USA.
Valerie B
VB
Holcomb
Jina
J
Hong
Nomelí P
NP
Núñez
D000428:Alcohol Drinking / Q000009:adverse effects; D000818:Animals; D004032:Diet; D004343:Drug Implants; D004967:Estrogens / Q000008:administration & dosage*; D000431:Ethanol / Q000009:adverse effects*; D005234:Fatty Liver / Q000209:etiology / Q000517:prevention & control; D005260:Female; D007334:Insulin-Like Growth Factor I / Q000032:analysis; D008325:Mammary Neoplasms, Experimental / Q000209:etiology* / Q000473:pathology / Q000517:prevention & control*; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009765:Obesity / Q000150:complications*; D010052:Ovariectomy; D012307:Risk Factors; D042461:Vascular Endothelial Growth Factor A / Q000097:blood; D051155:Wnt1 Protein / Q000235:genetics
D004343:Drug Implants; D004967:Estrogens; D042461:Vascular Endothelial Growth Factor A; D051155:Wnt1 Protein; C495246:Wnt1 protein, mouse; D000431:Ethanol; D007334:Insulin-Like Growth Factor I