A high concentration of genistein down-regulates activin A, Smad3 and other TGF-β pathway genes in human uterine leiomyoma cells.
Previously, we found that high doses of genistein show an inhibitory effect on uterine leiomyoma (UtLM) cell proliferation. In this study, using microarray analysis and Ingenuity Pathways Analysis™, we identified genes (up- or down-regulated, ≥ 1.5 fold, P ≤ 0.001), functions and signaling pathways that were altered following treatment with an inhibitory concentration of genistein (50 μg/ml) in UtLM cells. Downregulation of TGF-β signaling pathway genes, activin A, activin B, Smad3, TGF-β2 and genes related to cell cycle regulation, with the exception of the upregulation of the CDK inhibitor P15, were identified and validated by real- time RT-PCR studies. Western blot analysis further demonstrated decreased protein expression of activin A and Smad3 in genistein-treated UtLM cells. Moreover, we found that activin A stimulated the growth of UtLM cells, and the inhibitory effect of genistein was partially abrogated in the presence of activin A. Overexpression of activin A and Smad3 were found in tissue samples of leiomyoma compared to matched myometrium, supporting the contribution of activin A and Smad3 in promoting the growth of UtLM cells. Taken together, these results suggest that downregulation of activin A and Smad3, both members of the TGF-β pathway, may offer a mechanistic explanation for the inhibitory effect of a high-dose of genistein on UtLM cells, and might be potential therapeutic targets for treatment of clinical cases of uterine leiomyomas.
Molecular Pathogenesis Group, National Toxicology Program (NTP) Laboratories Branch, National Institute of Environmental Health Sciences, National Institutes of Health (NIH), Research Triangle Park, North Carolina 27709, USA.
Xudong
X
Di
Danica M K
DM
Andrews
Charles J
CJ
Tucker
Linda
L
Yu
Alicia B
AB
Moore
Xiaolin
X
Zheng
Lysandra
L
Castro
Tonia
T
Hermon
Hang
H
Xiao
Darlene
D
Dixon
D028341:Activins / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology; D016588:Anticarcinogenic Agents / Q000494:pharmacology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D050762:Cyclin-Dependent Kinase Inhibitor p15 / Q000235:genetics / Q000378:metabolism; D015536:Down-Regulation; D005260:Female; D019833:Genistein / Q000494:pharmacology*; D006801:Humans; D007889:Leiomyoma / Q000378:metabolism*; D020411:Oligonucleotide Array Sequence Analysis; D015398:Signal Transduction / Q000187:drug effects; D051900:Smad3 Protein / Q000235:genetics* / Q000378:metabolism; D016212:Transforming Growth Factor beta / Q000235:genetics* / Q000378:metabolism; D015854:Up-Regulation; D014594:Uterine Neoplasms / Q000378:metabolism*
D016588:Anticarcinogenic Agents; D050762:Cyclin-Dependent Kinase Inhibitor p15; C497790:SMAD3 protein, human; D051900:Smad3 Protein; D016212:Transforming Growth Factor beta; C422405:activin A; C044147:activin B; D028341:Activins; D019833:Genistein