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Updated: Aug 17, 2026

Profiling of Estrogen-regulated MicroRNAs in Breast Cancer Cells
Published on: February 21, 2014
Does tamoxifen change oestrogen and progesterone receptor expression in the endometrium and breast?
1Department of Obstetrics and Gynaecology, University of Freiburg, Hugstetter Strabetae 55, 79106, Freiburg, Germany. ukarck@frk1.ukl.uni-freiburg.de
Abstract:
We studied the expression of oestrogen and progesterone receptors (ER, PR) in postmenopausal women receiving tamoxifen for breast cancer. In addition the literature addressing the question of ER and PR expression in breast tissue during treatment with tamoxifen was reviewed. We demonstrated consistent expression of ER and PR in endometria from patients receiving tamoxifen, with a trend towards a higher proportion of receptor positive specimens during tamoxifen. In breast cancer tissue, the ER content seemed to be reduced following tamoxifen treatment. After short time exposure to tamoxifen, the PR appeared to be increased, longer treatment caused the PR to go down to pretreatment levels or below.
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