title: Identification of sequence alterations in the upstream regulatory region of the estrogen receptor gene in an ER-negative breast cancer cell line.
abstract: Given the important role of the estrogen receptor (ER) in the development and physiology of the breast, it is essential to delineate the mechanisms responsible for its failed expression in some breast tumors. We have cloned and sequenced a portion of the ER upstream regulatory region from the ER-positive MCF-7 and the ER-negative MDA-MB-231 breast cancer cell lines to determine if sequence alterations in this region account for the ER-negative phenotype of some tumors. From this, we identified a number of variations between the sequences, two of which were determined to be associated with a 50% decrease in CAT activity.
authors.affiliation: Department of Anatomy, Tulane University School of Medicine, New Orleans, LA 70112, USA.
authors.forename: J A
authors.initials: JA
authors.lastname: Sullivan
authors.forename: C S
authors.initials: CS
authors.lastname: Cohn
authors.forename: S M
authors.initials: SM
authors.lastname: Hill
mesh_terms: D001483:Base Sequence; D001943:Breast Neoplasms / Q000201:enzymology / Q000235:genetics*; D015500:Chloramphenicol O-Acetyltransferase / Q000235:genetics / Q000378:metabolism; D003001:Cloning, Molecular; D005260:Female; D014644:Genetic Variation; D006801:Humans; D007962:Leukocytes; D008969:Molecular Sequence Data; D011960:Receptors, Estrogen / Q000235:genetics*; D012045:Regulatory Sequences, Nucleic Acid; D012689:Sequence Homology, Nucleic Acid; D014407:Tumor Cells, Cultured
chemical_list: D011960:Receptors, Estrogen; D015500:Chloramphenicol O-Acetyltransferase