Publications by authors named "Elise F Saunier"

Long-term estrogen deficiency increases the risk of obesity, diabetes and metabolic syndrome in postmenopausal women. Menopausal hormone therapy containing estrogens might prevent these conditions, but its prolonged use increases the risk of breast cancer, as wells as endometrial cancer if used without progestins. Animal studies indicate that beneficial effects of estrogens in adipose tissue and adverse effects on mammary gland and uterus are mediated by estrogen receptor alpha (ERα).

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TGF-β is produced excessively by many solid tumors and can drive malignant progression through multiple effects on the tumor cell and microenvironment. TGF-β signaling pathway inhibitors have shown efficacy in preclinical models of metastatic cancer. Here, we investigated the effect of systemic LY2109761, a TGF-β type I/II receptor (TβRI/TβRII) kinase inhibitor, in both a tumor allograft model and the mouse skin model of de novo chemically induced carcinogenesis in vivo.

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Estrogenic effects are mediated through two estrogen receptor (ER) subtypes, ERα and ERβ. Estrogens are the most commonly prescribed drugs to treat menopausal conditions, but by non-selectively triggering both ERα and ERβ pathways in different tissues they can cause serious adverse effects. The different sizes of the binding pockets and sequences of their activation function domains indicate that ERα and ERβ should have different specificities for ligands and biological responses that can be exploited for designing safer and more selective estrogens.

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Estrogen receptor beta (ERbeta) has potent antiproliferative and anti-inflammatory properties, suggesting that ERbeta-selective agonists might be a new class of therapeutic and chemopreventive agents. To understand how ERbeta regulates genes, we identified genes regulated by the unliganded and liganded forms of ERalpha and ERbeta in U2OS cells. Microarray data demonstrated that virtually no gene regulation occurred with unliganded ERalpha, whereas many genes were regulated by estradiol (E(2)).

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3,3'-Diindolylmethane (DIM) is a natural compound found in cruciferous vegetables that has antiproliferative and estrogenic activity. However, it is not clear whether the estrogenic effects are mediated through estrogen receptor (ER)alpha, ERbeta, or both ER subtypes. We investigated whether DIM has ER subtype selectivity on gene transcription.

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Tamoxifen can stimulate the growth of some breast tumors and others can become resistant to tamoxifen. We previously showed that unliganded ERbeta inhibits ERalpha-mediated proliferation of MCF-7 cells. We investigated if tamoxifen might have a potential negative effect on some breast cancer cells by blocking the effects of unliganded ERbeta on gene regulation.

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Purpose: Nonmelanoma skin cancer incidence is enhanced >50-fold in patients taking antirejection drugs (ARD) following organ transplantation. Preclinical studies suggest that ARD treatment increases transforming growth factor-beta1 (TGF-beta1) levels, which contribute to enhanced tumor susceptibility independent of the immunosuppressive effects of ARDs. This study investigates whether TGF-beta signaling is elevated in transplant patients.

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Post-translational sumoylation, the covalent attachment of a small ubiquitin-like modifier (SUMO), regulates the functions of proteins engaged in diverse processes. Often associated with nuclear and perinuclear proteins, such as transcription factors, it is not known whether SUMO can conjugate to cell-surface receptors for growth factors to regulate their functions. Here we show that the type I transforming growth factor-beta (TGF-beta) receptor, T beta RI, is sumoylated in response to TGF-beta and that its sumoylation requires the kinase activities of both T beta RI and the type II TGF-beta receptor, T beta RII.

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The importance of perturbation in transforming growth factor beta (TGFbeta) signaling for the onset and progression of cancer is well established. Many tumors over express TGFbeta, and high circulating levels of TGFbeta1 in cancer patients are frequently associated with poor prognosis. TGFbeta has context-dependent biphasic action during tumorigenesis.

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The human TGFB1 gene is polymorphic, and genetic variants are associated with altered cancer risk. However, human genetic association studies have had variable outcomes because TGFbeta1 action is context-dependent. We used the murine skin model of chemical carcinogenesis in genetic linkage analysis of three independent Mus musculus NIH/Ola x (Mus spretus x M.

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Expression of the Coxsackie and Adenovirus Receptor (CAR) is frequently reduced in carcinomas, resulting in decreased susceptibility of such tumors to infection with therapeutic adenoviruses. Because CAR participates physiologically in the formation of tight-junction protein complexes, we examined whether molecular mechanisms known to down-regulate cell-cell adhesions cause loss of CAR expression. Transforming growth factor-beta (TGF-beta)-mediated epithelial-mesenchymal transition (EMT) is a phenomenon associated with tumor progression that is characterized by loss of epithelial-type cell-cell adhesion molecules (including E-cadherin and the tight junction protein ZO-1), gain of mesenchymal biochemical markers, such as fibronectin, and acquisition of a spindle cell phenotype.

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