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Updated: Apr 20, 2026

Profiling of Estrogen-regulated MicroRNAs in Breast Cancer Cells
Published on: February 21, 2014
Estrogen and progesterone receptors in breast cancer
Cheng-Har Yip1, Anthony Rhodes
1Department of Surgery, University Malaya Medical Centre, Kuala Lumpur, Malaysia.
Abstract:
Breast cancer is the most common cancer in women worldwide. The majority of breast cancers show overexpression of estrogen receptors (ERs) and progesterone receptors (PRs). The development of drugs to target these hormone receptors, such as tamoxifen, has brought about significant improvement in survival for women with hormone receptor-positive breast cancers. Since information about ER and PR is vital for patient management, quality assurance is important to ensure accurate testing. In recent guidelines, the recommended definition of ER and PR positivity is 1% or more of cells that stain positive. Semiquantitative assessment of ER and PR is important for prognosis and, hence, management. Even with the development of genomic tests, hormone receptor status remains the most significant predictive and prognostic biomarker.
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