Gene expression profiling reveals novel regulation by bisphenol-A in estrogen receptor-alpha-positive human cells.
Bisphenol-A (BPA) shows proliferative actions in uterus and mammary glands and may influence the development of male and female reproductive tracts in utero or during early postnatal life. Because of its ability to function as an estrogen receptor (ER) agonist, BPA has the potential to disrupt normal endocrine signaling through regulation of ER target genes. Some genes are regulated by both estradiol (E2) and BPA, but those exclusive to either agent have not been described. Using a yeast strain incorporating a vitellogenin A2 ERE-LacZ reporter gene into the genome, we found that BPA induced expression of the reporter in colonies transformed with the ERalpha expression plasmid, illustrating BPA-mediated regulation within a chromatin context. Additionally, a reporter gene transiently transfected into the endometrial cancer (Ishikawa) cell line also showed BPA activity, although at 100-fold less potency than E2. To compare global gene expression in response to BPA and E2, we used a variant of the MCF-7 breast cancer cell line stably expressing HA-tagged ERalpha. Cultures were treated for 3h with an ethanol vehicle, E2 (10(-8)M), or BPA (10(-6)M), followed by isolation of RNA and microarray analysis with the human U95A probe array (Affymetrix, Santa Clara, CA, USA). More than 300 genes were changed 2-fold or more by either or both agents, with roughly half being up-regulated and half down-regulated. A number of growth- and development-related genes, such as HOXC1 and C6, Wnt5A, Frizzled, TGFbeta-2, and STAT inhibitor 2, were found to be affected exclusively by BPA. We used quantitative real-time PCR to verify regulation of the HOXC6 gene, which showed decreased expression of approximately 2.5-fold by BPA. These results reveal novel effects by BPA and E2, raising interesting possibilities regarding the role of endocrine disruptors in sexual development.
Singleton
David W
DW
Department of Cell Biology, Neurobiology, and Anatomy, Vontz Center for Molecular Studies, University of Cincinnati, 3125 Eden Avenue, Cincinnati, OH 45267-0521, USA.
Feng
Yuxin
Y
Yang
Jun
J
Puga
Alvaro
A
Lee
Adrian V
AV
Khan
Sohaib A
SA
D001559:Benzhydryl Compounds; D045744:Cell Line, Tumor; D047108:Embryonic Development; D004785:Environmental Pollutants / Q000633:toxicity*; D047628:Estrogen Receptor alpha / Q000235:genetics / Q000378:metabolism*; D004968:Estrogens, Non-Steroidal / Q000633:toxicity*; D005260:Female; D020869:Gene Expression Profiling; D017930:Genes, Reporter; D005835:Genitalia / Q000187:drug effects / Q000196:embryology; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008297:Male; D018811:Maternal Exposure; D046228:Microarray Analysis; D010636:Phenols / Q000633:toxicity*; D011247:Pregnancy; D020218:Response Elements; D000098826:Bisphenol A Compounds
D001559:Benzhydryl Compounds; D004785:Environmental Pollutants; D047628:Estrogen Receptor alpha; D004968:Estrogens, Non-Steroidal; D018398:Homeodomain Proteins; D010636:Phenols; C094289:HOXC6 protein, human; C006780:bisphenol A; D000098826:Bisphenol A Compounds