ESR1
ESR1
Overview
ESR1 (Estrogen Receptor 1), also known as estrogen receptor alpha (ERα), is a nuclear receptor encoded by the ESR1 gene located on chromosome 6q25.1 in humans. As a ligand-activated transcription factor, ESR1 mediates the biological effects of estrogen by binding to estrogen response elements (EREs) in the promoters of target genes, thereby regulating cell proliferation, differentiation, and survival across multiple tissue types including the breast, uterus, ovary, bone, and liver. Upon estrogen binding, ESR1 undergoes conformational changes that promote receptor dimerization, coactivator recruitment, and transcriptional activation of downstream targets involved in cell cycle progression and apoptosis suppression. Beyond its canonical genomic signaling, ESR1 also participates in rapid non-genomic signaling cascades intersecting with the PI3K/Akt signaling pathway and JAK2/STAT3 signaling pathway, amplifying its influence over cellular behavior.
ESR1 holds central clinical importance because the majority of breast cancers — approximately 70–80% of diagnoses — are estrogen receptor-positive (ER+), making ESR1 the primary therapeutic target for endocrine therapies such as selective estrogen receptor modulators (SERMs), aromatase inhibitors, and selective estrogen receptor degraders (SERDs). Activating mutations in ESR1, particularly in the ligand-binding domain, frequently emerge under the selective pressure of hormone-based treatments and are a major mechanism of acquired endocrine resistance in advanced breast cancer. Beyond oncology, ESR1 is implicated in reproductive disorders including polycystic ovary syndrome (PCOS) and endometriosis, as well as in metabolic and inflammatory conditions, underscoring its broad physiological relevance.
Recent Publications Focus
Below is a summary of the newest research publications targeting ESR1 (sorted by publication date).
Recent literature continues to emphasize ESR1 as a central node in endocrine-responsive breast cancer and related resistance mechanisms. A review of emerging endocrine-directed therapies highlighted that acquired ESR1 mutations are a major driver of endocrine resistance in metastatic hormone receptor-positive, HER2-negative breast cancer, promoting ligand-independent estrogen receptor activation and reduced sensitivity to standard antiestrogens. The article also summarized clinical and translational evidence for next-generation estrogen receptor-directed agents, including oral selective estrogen receptor degraders (SERDs), and noted encouraging activity in ESR1-mutant disease, particularly when combined with Cdk4/6 inhibitors or agents targeting the PI3K/AKT pathway. The same review discussed the growing role of circulating tumor DNA monitoring for acquired ESR1 mutations to support earlier treatment switching, while also noting unresolved questions about optimal sequencing and comparative efficacy among newer endocrine therapies.
Several recent studies used computational and experimental approaches to place ESR1 within broader disease-associated networks beyond breast cancer. In a network pharmacology and docking analysis of the nutraceutical formula Vernolac, ESR1 emerged among the key hub targets linked to predicted anticancer activity, alongside Akt1, BCL2, CASP3, EGFR, STAT3, SRC, and others. The study suggested that Vernolac phytochemicals may act through multiple cancer-related pathways, with in vitro testing showing selective antiproliferative effects against cancer cell lines. In a separate multi-omics investigation of di-(2-ethylhexyl) terephthalate (DOTP), ESR1 was identified as one of six high-affinity carcinogenic targets in docking analyses, and DOTP exposure was associated with increased ESR1 protein levels in tumor cells in a concentration-dependent manner, supporting a possible role in promoting breast cancer progression through pathways including PI3K-Akt-mTOR signaling.
ESR1 was also implicated in metabolic and toxicologic contexts. In a study of per- and polyfluoroalkyl substances (PFAS) and gestational diabetes mellitus, ESR1 and SIRT1 were identified as critical regulatory hubs connecting PFAS exposure to disrupted hepatic metabolic networks. Molecular docking and simulations supported stable interactions between PFAS and these targets, and mouse exposure to perfluoropentanoic acid was associated with maternal hepatic injury and transcriptomic changes in metabolic signaling pathways. Another network-based study of acute liver injury identified ESR1 among four hub genes, although JUN was the only gene consistently upregulated across transcriptomic datasets and was ultimately emphasized as the main candidate hub. Together, these studies place ESR1 within broader endocrine, metabolic, and toxicologic regulatory networks.
A more direct therapeutic link to ESR1 was reported in a study of traditional Chinese medicine combinations for cyclophosphamide-induced diminished ovarian reserve, where Guilu Erxian Glue plus Wuzi Yanzong Pill was reported to attenuate granulosa cell apoptosis and improve ovarian reserve through the lncRNA NEAT1/miR-204-5p/ESR1 axis. In parallel, a publication on the first approved PROTAC, vepdegestrant, underscored the clinical relevance of ESR1-mutant advanced breast cancer by describing targeted protein degradation as a validated therapeutic strategy and positioning ESR1-mutant disease as a setting in which this new modality may be especially useful.
Result PMIDs
- [PMID 41806689]
- [PMID 42065778]
- [PMID 42132418]
Target PMIDs
- [PMID 41616885]
- [PMID 41780785]
- [PMID 42007886]
- [PMID 42137912]
- [PMID 42208379]
- [PMID 42384725]
- [PMID 42413061]