An in vitro test system for the determination of estrogens, xeno- and phytoestrogens, based on the activation of human estrogen receptor-alpha, has been examined for ability in monitoring environmental estrogens. The system consists of an expression plasmid for the human estrogen receptor-alpha and a reporter plasmid containing the lacZ gene under the control of the vitellogenin hormone response element. These plasmids have been transformed into S. cerevisae. Cultivation of yeast in the presence of estrogenic substances leads to activation of the estrogen receptor and induces the expression of the reporter lacZ. beta-Galactosidase activity of the translated gene lacZ is a measure of the estrogenic activity of a compound. First, the selectivity of the system was compared to data available in the literature. Then the sensitivity of the system was checked. The detection limit is 0.1 ng 17-beta estradiol or an equivalent activity per liter, if a sample can be concentrated 1000-fold. The system has been further characterized by selected compounds with known and unknown estrogenic activity.
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http://dx.doi.org/10.1016/s1570-0232(02)00083-1 | DOI Listing |
World J Oncol
February 2025
Breast Surgery, Department of Surgical Oncology, Roswell Park Comprehensive Cancer Center, Buffalo, NY, USA.
Background: Peritumoral lidocaine infiltration prior to excision is associated with better survival in breast cancer (BC), which led us to hypothesize that innervation to the tumor affects its biology and patient survival. Activity-regulated cytoskeleton-associated protein (ARC) gene expression is known to be regulated by neuronal activity. Therefore, we studied the clinical relevance of ARC gene expression as a surrogate of neuronal activity in BC.
View Article and Find Full Text PDFInt J Nanomedicine
January 2025
Department of Medical Chemistry, Faculty of Medicine, Medical University of Gdansk, Gdansk, Poland.
Introduction: This article describes the invention of graphene oxide (GO) or reduced graphene oxide (rGO) functionalised with 2-methoxy estradiol. The presence of polar hydroxyl groups enables the binding of 2-ME to GO/rGO through hydrogen bonds with epoxy and hydroxyl groups located on the surface and carbonyl and carboxyl groups located at the edges of graphene flake sheets.
Methods: The patented method of producing the subject of the invention and the research results regarding its anticancer effectiveness via cytotoxicity in an in vivo model (against A375 melanoma and 143B osteosarcoma cells) are described.
Sci Rep
January 2025
The Second Department of Critical Care Medicine, The Second Affiliated Hospital of Anhui Medical University, Hefei, 230601, Anhui, China.
Although tamoxifen is commonly utilized as adjuvant therapy for Estrogen Receptor alpha (ERα)-positive breast cancer patients, approximately 30-50% of individuals treated with tamoxifen experience relapse. Therefore, it is essential to investigate additional factors besides ERα that influence the estrogen response. In this study, cross-analysis of databases were performed, and the results revealed a significant association between LINC00626 and ERα signaling as well as increased expression levels of this gene in tamoxifen-resistant cells.
View Article and Find Full Text PDFJ Steroid Biochem Mol Biol
January 2025
Laboratory of Experimental Endocrinology, Department of Pharmacology, Escola Paulista de Medicina (EPM), Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, 04039-032, Brazil. Electronic address:
The aims of this study were to investigate the localization of non-phosphorylated β‑catenin and Galectin-3 (GAL-3), the regulation of the expression of both proteins by activation of estrogen receptors (ERs) and their role in tumorigenic characteristics of androgen-independent prostate cancer DU-145 cells. DU-145 cells were cultured in the absence (control), and presence of 17β-estradiol (E2). Cells were also untreated or pre-treated with the inhibitor of GAL‑3, VA03, or with a compound that disrupts the complex β-catenin-TCF/LEF transcription factor, PKF 118-310.
View Article and Find Full Text PDFFood Chem
January 2025
College of Life Science, Shandong Agricultural University, Tai'an 271018, China. Electronic address:
Zearalenone (ZEN) is a widely distributed mycotoxin with potent estrogenic activity. Detecting ZEN is crucial for assessing its potential health risks. This study developed a highly sensitive non-competitive magnetic phage anti-immunocomplex immunoassay (Nc-MPHAIA) for ZEN detection, utilizing the anti-ZEN single-chain variable fragment (ScFv) and anti-immunocomplex peptide (AIcP), both of which were screened using phage display technology.
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