Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
2004-3-2
pubmed:abstractText
The soy isoflavones, genistein (5,7,4'-trihydroxyisoflavone) and daidzein (7,4'-dihydroxyisoflavone), are representative phytoestrogens that function as chemopreventive agents against cancers, cardiovascular disease, and osteoporosis. However, recent studies indicated that genistein and/or daidzein induced cancers of reproductive organs in rodents, such as the uterus and vulva. To clarify the molecular mechanisms underlying the induction of carcinogenesis by soy isoflavones, we examined the ability of genistein, daidzein, and their metabolites, 5,7,3',4'-tetrahydroxyisoflavone (orobol), 7,3',4'-trihydroxyisoflavone (7,3',4'-OH-IF), and 6,7,4'-trihydroxyisoflavone (6,7,4'-OH-IF), to cause DNA damage and cell proliferation. An E-screen assay revealed that genistein and daidzein enhanced proliferation of estrogen-sensitive breast cancer MCF-7 cells, while their metabolites had little or no effect. A surface plasmon resonance sensor showed that binding of isoflavone-liganded estrogen receptors (ER) to estrogen response elements (ERE) was largely consistent with cell proliferative activity of isoflavones. Orobol and 7,3',4'-OH-IF significantly increased 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) formation in human mammary epithelial MCF-10A cells, while genistein, daidzein, and 6,7,4'-OH-IF did not. Experiments using isolated DNA revealed a metal-dependent mechanism of oxidative DNA damage induced by orobol and 7,3',4'-OH-IF. DNA damage was enhanced by the addition of endogenous reductant NADH, formed via the redox cycle. These findings suggest that oxidative DNA damage by isoflavone metabolites plays a role in tumor initiation and that cell proliferation by isoflavones via ER-ERE binding induces tumor promotion and/or progression, resulting in cancer of estrogen-sensitive organs.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/8-oxo-7-hydrodeoxyguanosine, http://linkedlifedata.com/resource/pubmed/chemical/Carcinogens, http://linkedlifedata.com/resource/pubmed/chemical/Copper, http://linkedlifedata.com/resource/pubmed/chemical/DNA, http://linkedlifedata.com/resource/pubmed/chemical/Deoxyguanosine, http://linkedlifedata.com/resource/pubmed/chemical/Estrogen Receptor alpha, http://linkedlifedata.com/resource/pubmed/chemical/Estrogen Receptor beta, http://linkedlifedata.com/resource/pubmed/chemical/Estrogens, http://linkedlifedata.com/resource/pubmed/chemical/Genistein, http://linkedlifedata.com/resource/pubmed/chemical/Isoflavones, http://linkedlifedata.com/resource/pubmed/chemical/Ligands, http://linkedlifedata.com/resource/pubmed/chemical/NAD, http://linkedlifedata.com/resource/pubmed/chemical/Phosphorus Isotopes, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Estrogen, http://linkedlifedata.com/resource/pubmed/chemical/calf thymus DNA, http://linkedlifedata.com/resource/pubmed/chemical/daidzein
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
9
pubmed:volume
43
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2569-77
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:14992594-Breast Neoplasms, pubmed-meshheading:14992594-Carcinogens, pubmed-meshheading:14992594-Cell Division, pubmed-meshheading:14992594-Cell Line, pubmed-meshheading:14992594-Cell Line, Tumor, pubmed-meshheading:14992594-Copper, pubmed-meshheading:14992594-DNA, pubmed-meshheading:14992594-DNA Damage, pubmed-meshheading:14992594-DNA Fragmentation, pubmed-meshheading:14992594-Deoxyguanosine, pubmed-meshheading:14992594-Estrogen Receptor alpha, pubmed-meshheading:14992594-Estrogen Receptor beta, pubmed-meshheading:14992594-Estrogens, pubmed-meshheading:14992594-Genistein, pubmed-meshheading:14992594-Humans, pubmed-meshheading:14992594-Isoflavones, pubmed-meshheading:14992594-Ligands, pubmed-meshheading:14992594-NAD, pubmed-meshheading:14992594-Oxidative Stress, pubmed-meshheading:14992594-Phosphorus Isotopes, pubmed-meshheading:14992594-Protein Binding, pubmed-meshheading:14992594-Receptors, Estrogen, pubmed-meshheading:14992594-Response Elements
pubmed:year
2004
pubmed:articleTitle
Genistein and daidzein induce cell proliferation and their metabolites cause oxidative DNA damage in relation to isoflavone-induced cancer of estrogen-sensitive organs.
pubmed:affiliation
Department of Environmental and Molecular Medicine, Mie University School of Medicine, Tsu, Mie 514-8507, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't