TY - JOUR
T1 - Evaluation of wild yam (Dioscorea villosa) root extract as a potential epigenetic agent in breast cancer cells
AU - Aumsuwan, Pranapda
AU - Khan, Shabana I.
AU - Khan, Ikhlas A.
AU - Avula, Bharathi
AU - Walker, Larry A.
AU - Helferich, William G.
AU - Katzenellenbogen, Benita S.
AU - Dasmahapatra, Asok K.
N1 - Funding Information:
This work was supported in part by the United States Department of Agriculture (USDA), Agriculture Research Service Specific Cooperative Agreement no 58-6408-2009. This project was made possible by Grant Number P50AT006268 (to WGS, IK, and BSK) from the National Center for Complementary and Alternative Medicines (NCCAM), the Office of Dietary Supplements (ODS) and the National Cancer Institute (NCI). Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the NCCAM, ODS, NCI or the National Institutes of Health.
Publisher Copyright:
© 2014, The Society for In Vitro Biology.
PY - 2014/1
Y1 - 2014/1
N2 - The present study was designed to evaluate the efficacy of wild yam root extract (WYRE) as a potential demethylating agent using two breast cancer cell lines, MCF-7 (estrogen receptor positive; ER+) and MDA-MB-231 (Estrogen receptor negative; ER−), and a methylated gene, GATA3, as a potential marker of breast cancer development. The cells were treated with WYRE (0–50 μg/mL) for 72 h and used for viability, mRNA, and methylation analyses. WYRE significantly reduced viability of both cell lines and enhanced mRNA content of GATA3 in a concentration-dependent manner; however, DNMT mRNAs (DNMT1, 3A, 3B) were found to increase significantly only in MDA-MB-231 cells. Global DNA methylation, analyzed as 5′-methyl-2′-deoxycytidine (5-mC) and 5-hydroxymethylcytosine (5-hmC), showed a concentration-dependent enhancement of 5-mC with no alteration in 5-hmC level in MCF-7 cells; however, in MDA-MB-231 cells, in contrast to MCF-7 cells, 5-mC remained unaltered but 5-hmC reduced significantly in all WYRE concentrations (10–50 μg/mL) used in this study. Since 5-hmC is generated from 5-mC by ten-eleven-translocation (TET) enzymes, analysis of TET mRNAs (TET1, TET2, and TET3) in MDA-MB-231 cells indicated a concentration-dependent reduction in TET1 and induction of TET3; however, TET2 remained unaltered. No alterations in any of the TET mRNAs were found in MCF-7 cells. Methylation analysis of GATA3 promoter at specific locus indicates probable demethylating activity of WYRE in MDA-MB-231 cells. We conclude that activation of GATA3 gene in ER− MDA-MB-231 cells may occur by altering DNA methylation pattern on the promoter region which may be different from the mechanisms operated in ER+ MCF-7 cells.
AB - The present study was designed to evaluate the efficacy of wild yam root extract (WYRE) as a potential demethylating agent using two breast cancer cell lines, MCF-7 (estrogen receptor positive; ER+) and MDA-MB-231 (Estrogen receptor negative; ER−), and a methylated gene, GATA3, as a potential marker of breast cancer development. The cells were treated with WYRE (0–50 μg/mL) for 72 h and used for viability, mRNA, and methylation analyses. WYRE significantly reduced viability of both cell lines and enhanced mRNA content of GATA3 in a concentration-dependent manner; however, DNMT mRNAs (DNMT1, 3A, 3B) were found to increase significantly only in MDA-MB-231 cells. Global DNA methylation, analyzed as 5′-methyl-2′-deoxycytidine (5-mC) and 5-hydroxymethylcytosine (5-hmC), showed a concentration-dependent enhancement of 5-mC with no alteration in 5-hmC level in MCF-7 cells; however, in MDA-MB-231 cells, in contrast to MCF-7 cells, 5-mC remained unaltered but 5-hmC reduced significantly in all WYRE concentrations (10–50 μg/mL) used in this study. Since 5-hmC is generated from 5-mC by ten-eleven-translocation (TET) enzymes, analysis of TET mRNAs (TET1, TET2, and TET3) in MDA-MB-231 cells indicated a concentration-dependent reduction in TET1 and induction of TET3; however, TET2 remained unaltered. No alterations in any of the TET mRNAs were found in MCF-7 cells. Methylation analysis of GATA3 promoter at specific locus indicates probable demethylating activity of WYRE in MDA-MB-231 cells. We conclude that activation of GATA3 gene in ER− MDA-MB-231 cells may occur by altering DNA methylation pattern on the promoter region which may be different from the mechanisms operated in ER+ MCF-7 cells.
KW - Breast cancer
KW - DNMT
KW - Epigenetics
KW - Methylation
KW - TET
KW - Wild yam
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UR - http://www.scopus.com/inward/citedby.url?scp=84961290228&partnerID=8YFLogxK
U2 - 10.1007/s11626-014-9807-5
DO - 10.1007/s11626-014-9807-5
M3 - Article
C2 - 25148825
AN - SCOPUS:84961290228
VL - 51
SP - 59
EP - 71
JO - In Vitro
JF - In Vitro
SN - 0073-5655
IS - 1
ER -