Regulation of the Multidrug Resistance-Associated Protein Gene by Estrogen

Abstract

An observation was made that the mRNAs for two clones, #41 and #44, were rapidly repressed by estrogen in chick oviduct. Clone #44 shared sequence homology with members of the multidrug resistance-associated protein (mrp) gene family. This raised the question of whether the multidrug resistance (mdr) phenotype in breast cancer may be in part due to the loss of repression of MRP expression by estrogen when antiestrogens are administered. The goals of this last year where to complete the identification of clone #41, to ascertain whether human mrp gene expression is repressed by estrogen, and to determine whether estrogen is acting at the transcriptional or post-transcriptional levels. All but the first of these goals has been met, and a manuscript describing the work in chick is in review. These results have considerable significance in light of two recent reports that indicate that MRP mRNA is highly expressed in primary breast cancers, particularly those with poor prognosis. Our observations raise the possibility that one or more of the selective estrogen receptor modulators (SERMs) may be useful in treating those resistant cancers.

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Document Details

Document Type
Technical Report
Publication Date
Oct 01, 1999
Accession Number
ADA381694

Entities

People

  • Michel Sanders

Organizations

  • University of Minnesota

Tags

DTIC Thesaurus Topics

  • Amino Acids
  • Breast Cancer
  • Cell Line
  • Cells
  • Chemistry
  • Gene Expression
  • Genes
  • Genetic Structures
  • Genetics
  • Hormone Antagonists
  • Materials
  • Molecules
  • Neoplasms
  • Observation
  • Phenotypes
  • Polymerase Chain Reaction
  • Tumor Cell Line

Fields of Study

  • Biology

Readers

  • Breast cancer cell signaling and growth regulation.
  • Molecular Genetics
  • Oncology (Cancer Research).