Tetrahydro-iso-alpha Acids Antagonize Estrogen Receptor Alpha Activity in MCF-7 Breast Cancer Cells

Tetrahydro-iso-alpha acids commonly called THIAA or Tetra are modified hop acids extracted from hop (Humulus lupulus L.) which are frequently used in brewing industry mainly in order to provide beer bitterness and foam stability. Interestingly, molecular structure of tetrahydro-iso-alpha acids is cl...

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Bibliographic Details
Main Authors: Maëlle Lempereur, Claire Majewska, Amandine Brunquers, Sumalee Wongpramud, Bénédicte Valet, Philippe Janssens, Monique Dillemans, Laurence Van Nedervelde, Dominique Gallo
Format: Article
Language:English
Published: Hindawi Limited 2016-01-01
Series:International Journal of Endocrinology
Online Access:http://dx.doi.org/10.1155/2016/9747863
Description
Summary:Tetrahydro-iso-alpha acids commonly called THIAA or Tetra are modified hop acids extracted from hop (Humulus lupulus L.) which are frequently used in brewing industry mainly in order to provide beer bitterness and foam stability. Interestingly, molecular structure of tetrahydro-iso-alpha acids is close to a new type of estrogen receptor alpha (ERα) antagonists aimed at disrupting the binding of coactivators containing an LxxLL motif (NR-box). In this work we show that THIAA decreases estradiol-stimulated proliferation of MCF-7 (ERα-positive breast cancer cells). Besides, we show that it inhibits ERα transcriptional activity. Interestingly, this extract fails to compete with estradiol for ERα binding and does not significantly impact the receptor turnover rate in MCF-7 cells, suggesting that it does not act like classical antiestrogens. Hence, we demonstrate that THIAA is able to antagonize ERα estradiol-induced recruitment of the LxxLL binding motif.
ISSN:1687-8337
1687-8345