Down-regulates ESR1 protein levels through the ubiquitination-proteasome pathway, regardless of the presence of 17 beta-estradiol. Also involved in 17 beta-estradiol-induced ESR1 degradation. Controls PGR protein levels through a similar mechanism.
Subcellular locations: Cytoplasm, Nucleus
Significantly up-regulated in breast tumor tissues compared with matched adjacent normal tissues (at protein level). Levels inversely correlate with ESR1 in breast cancers and are lower in low-grade tumors compared to high-grade tumors.