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Aryl hydrocarbon receptor modulation of estrogen receptor α-mediated gene regulation by a multimeric chromatin complex involving the two receptors and the coregulator RIP140.Madak-Erdogan Z, Katzenellenbogen B.S., Toxicological Sciences. 2012 Feb;125(2):401-11

Although crosstalk between aryl hydrocarbon receptor (AhR) and estrogen receptor α (ERα) is well established, the mechanistic basis and involvement of other proteins in this process are not known. Because we observed an enrichment of AhR-binding motifs in ERα-binding sites of many estradiol (E2)-regulated genes, we investigated how AhR might modulate ERα-mediated gene transcription in […]

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Macrophage-elicited loss of estrogen receptor-α in breast cancer cells via involvement of MAPK and c-Jun at the ESR1 genomic locus.Stossi F, Madak-Erdoğan Z, Katzenellenbogen BS.Oncogene. 2012 Apr 5;31(14):1825-34

Estrogen receptor-α (ERα, ESR1) is a pivotal transcriptional regulator of breast cancer physiology and is targeted by endocrine therapies. Loss of ERα activity or expression is an indication of endocrine resistance and is associated with increased risk of tumor recurrence and worse prognosis. In this study, we sought to investigate whether elements of the tumor […]

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Genomic Collaboration of Estrogen Receptor alpha (ERα) and Extracellular Signal-Regulated Kinase 2 in Regulating Gene and Proliferation Programs, Madak-Erdogan Z, Lupien M, Stossi F., Brown M, Katzenellenbogen BS, Molecular and Cellular Biology. 2011, Jan;31(1):226-36

The nuclear hormone receptor, estrogen receptor α (ERα), and mitogen-activated protein kinases (MAPKs) play key roles in hormone-dependent cancers, and yet their interplay and the integration of their signaling inputs remain poorly understood. In these studies, we document that estrogen-occupied ERα activates and interacts with extracellular signal-regulated kinase 2 (ERK2), a downstream effector in the […]

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Estrogen Receptor Alpha Represses Transcription of Early Target Genes via p300 and CtBP1, Stossi F, Madak-Erdogan Z, Katzenellenbogen BS, Molecular and Cellular Biology. 2009 Apr;29(7):1749-59

The regulation of gene expression by nuclear receptors controls the phenotypic properties and diverse biologies of target cells. In breast cancer cells, estrogen receptor alpha (ERalpha) is a master regulator of transcriptional stimulation and repression, yet the mechanisms by which agonist-bound ERalpha elicits repression are poorly understood. We analyzed early estrogen-repressed genes and found that […]

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Nuclear and Extranuclear Pathway Inputs in the Regulation of Global Gene Expression by Estrogen Receptors, Madak-Erdogan Z, Kieser KJ, Kim SH, Komm B, Katzenellenbogen JA, Katzenellenbogen BS,Molecular Endocrinology. 2008; 22 (9): 2116-2127

Whereas estrogens exert their effects by binding to nuclear estrogen receptors (ERs) and directly altering target gene transcription, they can also initiate extranuclear signaling through activation of kinase cascades. We have investigated the impact of estrogen-mediated extranuclear-initiated pathways on global gene expression by using estrogen-dendrimer conjugates (EDCs), which because of their charge and size remain […]

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Estrogen dendrimer conjugates that preferentially activate extranuclear, nongenomic versus genomic pathways of estrogen action, Harrington WR, Kim SH, Funk CC, Madak-Erdogan Z, Schiff R, Katzenellenbogen JA, Katzenellenbogen BS, Molecular Endocrinology. 2006; 20(3):491-502.

Estrogenic hormones are classically thought to exert their effects by binding to nuclear estrogen receptors and altering target gene transcription, but estrogens can also have nongenomic effects through rapid activation of membrane-initiated kinase cascades. The development of ligands that selectively activate only the nongenomic pathways would provide useful tools to investigate the significance of these […]

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