Primary cultured human breast epithelial cells up-regulate protein disulfide isomerase in response to zeranol.
BACKGROUND
Experimental data at the molecular, cellular and organismal levels have implicated dietary components in cancer. Exposure to numerous growth factors, hormones and environmental agents, that can regulate signaling events, is involved in carcinogenesis. Research targets on gene-nutrient interactions may give useful information for the development of a novel diet-based intervention for the at-risk population.


METHODS
To examine the proteomic effect of a low level dietary compound on potential breast cancer, primary human breast epithelial cells were isolated and cultured in media with or without zeranol, an anabolic, non-estrogenic growth promoter with estrogenic activity, used in beef cattle and naturally found in some fungus in grain. The cells then underwent proteomic analysis.


RESULTS
2-D electrophoresis showed that protein disulfide isomerase (PDI) was up-regulated 5-fold in the breast epithelial cells exposed to zeranol. PDI has been shown to be up-regulated in a variety of cancerous tissues, although this is the first reported up-regulation of PDI in breast tissue.


CONCLUSIONS
PDI may be a useful marker of dietary exposure to zeranol.
Updike
Michael Scott
MS
Department of Animal Sciences, College of Food, Agricultural and Environmental Sciences, College of Medicine and Public Health, The Ohio State University, Columbus, OH 43210, USA.
Sawdy
Joseph C
JC
Wang
Li-Shu
LS
Liu
Suling
S
Huang
Yi-Wen
YW
Ye
Weiping
W
Farrar
William B
WB
Lin
Young C
YC
Wick
Macdonald
M
D000595:Amino Acid Sequence; D001940:Breast / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology*; D015180:Electrophoresis, Gel, Two-Dimensional; D004847:Epithelial Cells / Q000187:drug effects / Q000201:enzymology; D004968:Estrogens, Non-Steroidal / Q000494:pharmacology*; D006801:Humans; D008969:Molecular Sequence Data; D019704:Protein Disulfide-Isomerases / Q000096:biosynthesis*; D015854:Up-Regulation / Q000187:drug effects; D015029:Zeranol / Q000494:pharmacology*
D004968:Estrogens, Non-Steroidal; D015029:Zeranol; D019704:Protein Disulfide-Isomerases