ESR1 (Ab-104) Antibody
Description
Basic Characteristics
The antibody possesses the following fundamental properties:
| Property | Specification |
|---|---|
| Host Species | Rabbit |
| Species Reactivity | Human, Mouse |
| Antibody Type | Polyclonal |
| Clonality | Polyclonal |
| Isotype | IgG |
| Conjugation | Non-conjugated |
| Target | ESR1 (Estrogen Receptor alpha) |
| Target Aliases | ER, ESR, ESR1, ESTR, ESTRA |
| UniProt ID | P03372 |
The antibody specifically recognizes the estrogen receptor alpha protein, which functions as a nuclear hormone receptor involved in the regulation of eukaryotic gene expression and affects cellular proliferation and differentiation in target tissues .
Physical Properties and Formulation
The antibody is supplied in a stabilized liquid formulation with specific buffer components:
| Property | Specification |
|---|---|
| Concentration | 1.0 mg/mL |
| Buffer Composition | Phosphate buffered saline (without Mg²⁺ and Ca²⁺), pH 7.4, 150mM NaCl, 0.02% sodium azide and 50% glycerol |
| Form | Liquid |
| Size | 100 μL |
| Purification Method | Affinity chromatography using epitope-specific peptide |
This formulation ensures stability during storage and minimizes background interference during experimental applications .
Manufacturing Process and Quality Control
The production of ESR1 (Ab-104) Antibody follows standardized immunological procedures to ensure consistent quality and specificity.
Immunogen and Production
The antibody is generated through a systematic immunization process:
-
Synthetic peptide corresponding to amino acids 102-106 (S-V-S-P-S) of human estrogen receptor alpha is conjugated to KLH (Keyhole Limpet Hemocyanin) carrier protein
-
Rabbits are immunized with this conjugated peptide
-
Serum is collected and processed for antibody isolation
-
The antibodies undergo purification via affinity chromatography using the epitope-specific peptide
This approach yields high-specificity antibodies against the target epitope while minimizing non-specific binding to other cellular proteins.
Validated Applications and Protocols
ESR1 (Ab-104) Antibody has been validated for multiple research applications, each with specific recommended protocols and dilutions.
Application Range
The antibody performs effectively in the following experimental contexts:
| Application | Recommended Dilution |
|---|---|
| Western Blot (WB) | 1:500-1:1000 |
| Immunohistochemistry (IHC) | 1:50-1:200 |
| ELISA | 1:2000-1:10000 |
These applications allow researchers to detect and analyze ESR1 expression across various experimental systems .
Application Examples
Experimental validation of the antibody has been documented in specific research contexts:
-
Western Blot Analysis: The antibody effectively detects ESR1 protein in extracts from MCF-7 breast cancer cell lines, demonstrating specificity for the target protein .
-
Immunohistochemistry: The antibody has been successfully employed for immunohistochemical analysis of paraffin-embedded human breast carcinoma tissue. Specificity has been confirmed through blocking peptide experiments, which showed elimination of staining when the antibody was pre-incubated with the immunizing peptide .
These validated applications highlight the antibody's utility in cancer research, particularly in studies involving estrogen receptor-positive breast cancer models.
ESR1 Biological Context and Research Significance
Understanding the biological context of ESR1 provides valuable perspective on the research significance of ESR1 (Ab-104) Antibody.
ESR1 Biological Function
Estrogen receptor alpha (ESR1) is a member of the nuclear receptor superfamily, functioning primarily as a ligand-activated transcription factor. Upon binding estrogen, ESR1:
-
Undergoes dimerization and intranuclear translocation
-
Binds to estrogen response elements (EREs) on DNA
-
Regulates transcription of downstream genes
ESR1 is expressed in various tissues including mammary gland, uterus, skeleton, and cardiovascular system, playing crucial roles in maintaining physiological functions of these tissues .
ESR1 in Disease Context
ESR1 has significant implications in multiple disease states, particularly:
-
Breast Cancer: ESR1 is a key driver in many breast cancers, with approximately 70% of breast cancers classified as ER-positive
-
Endocrine Resistance: Mutations in ESR1 (especially around amino acids 536-538) are associated with acquired resistance to endocrine therapy in metastatic breast cancer, occurring in up to 40% of ER+, HER2- metastatic cases
-
Subtype Switching: Recent research indicates that ESR1 mutations can induce basal marker expression in luminal breast cancer cells, suggesting a role in subtype plasticity
These contexts highlight the importance of specific antibodies like ESR1 (Ab-104) in studying ESR1 protein modification, localization, and function.
Post-Translational Modifications
ESR1 undergoes multiple post-translational modifications that regulate its activity, including phosphorylation at serine residues 104, 106, 118, and 167. The region targeted by ESR1 (Ab-104) Antibody (amino acids 102-106) contains serine 104, which is a known phosphorylation site that influences AF-1 dependent transcriptional activity .
Research Applications in ESR1 Mutant Breast Cancer
Recent studies examining ESR1 mutations reveal compelling research applications for ESR1 (Ab-104) Antibody.
ESR1 Mutations and Phenotypic Changes
Current research has identified that ESR1 mutant tumors display distinct phenotypic characteristics:
-
Significant enrichment of basal subtype markers, particularly basal cytokeratins (BCKs)
-
Chromatin reprogramming centered around progesterone receptor-orchestrated insulated neighborhoods
-
Enriched immune pathways, with increased expression of immune mediators such as S100A8 and S100A9
The antibody targeting the region around amino acids 102-106 can help detect wild-type ESR1 expression levels in comparison to mutant forms, potentially contributing to research on resistance mechanisms.
Diagnostic and Therapeutic Implications
The application of ESR1 antibodies in research extends to potential diagnostic and therapeutic approaches:
-
Monitoring ESR1 expression levels in response to endocrine therapy
-
Studying the changes in ESR1 localization and function in mutant contexts
-
Evaluating the efficacy of novel therapeutic strategies targeting ESR1-dependent pathways
These applications underscore the importance of well-characterized antibodies in translational research bridging basic science and clinical applications.
Comparative Analysis with Other ESR1 Antibodies
When selecting an appropriate antibody for ESR1 research, it's important to consider how ESR1 (Ab-104) Antibody compares to other available options.
Target Epitope Considerations
Different ESR1 antibodies target distinct epitopes that may be differently accessible depending on:
-
Protein conformation
-
Presence of post-translational modifications
-
Protein-protein interactions
-
Mutation status
ESR1 (Ab-104) Antibody specifically targets the region around amino acids 102-106, which is distinct from the ligand-binding domain (where many clinically relevant mutations occur). This makes it potentially useful for detecting total ESR1 levels regardless of mutation status in the ligand-binding domain .
Product Specs
Target Background
- Estrogen-induced miR-191 has been identified as a direct upstream regulator of DAB2 in ER-positive breast cancer cells. PMID: 29247596
- This research provides comprehensive genome-wide insights that contribute to a deeper understanding of ER1's biological roles in breast cancer. PMID: 30301189
- The study revealed a correlation between rs2046210 and rs3803662, and the risk of developing breast cancer in Vietnamese women. The A allele is identified as the risk allele for both rs2046210 (OR [95% CI] = 1.43 [1.14 - 1.78], P = 0.0015) and rs3803662 (OR [95% CI] = 1.45 [1.16 - 1.83], P = 0.001). The findings indicate that two polymorphisms, rs2046210 in ESR1 and rs3803662 in TNRC9, are associated with breast cancer risk in the Vietnamese population. PMID: 30078824
- The study demonstrated that estrogen receptor alpha can enhance odonto/osteogenic differentiation of stem cells from apical papilla via ERK and JNK MAPK pathways. PMID: 30069950
- No association was found between polymorphisms in genes encoding estrogen receptors (ESR1 and ESR2) and excreted BPA levels in orthodontic patients after bracket bonding. PMID: 29961922
- Analysis of genome-wide ER binding sites revealed mutant ER unique recruitment mediating the allele-specific transcriptional program. PMID: 29438694
- The study identified RNF8 as a co-activator of ERalpha that enhances ERalpha stability via a post-transcriptional pathway. This finding provides a new perspective on the mechanisms by which RNF8 promotes cell growth in ERalpha-positive breast cancer. PMID: 28216286
- Reduced expression of ERbeta1 in female ERalpha-negative papillary thyroid carcinoma patients is associated with greater disease progression. PMID: 29655286
- ERα and ERβ exhibit a heterogeneous distribution in deep infiltrating endometriosis. PMID: 29383962
- The ER-alpha36/EGFR signaling loop promotes the growth of hepatocellular carcinoma cells. PMID: 29481815
- The study investigated the presence and localization of estrogen receptors (ERs), progesterone receptors (PRs), and androgen receptors (ARs) in both healthy and varicose vein wall cells and their relationship with gender. PMID: 30250632
- Estrogen receptor-alpha expression was observed only in women and showed a positive correlation with the amount of fungi in oral paracoccidioidomycosis. Progesterone receptor was present in both genders but exhibited no correlation with estrogen receptor-alpha or fungi counting. PMID: 29796757
- ERalpha upregulates vinculin expression in breast cancer cells, while loss of vinculin promotes amoeboid features of cancer cells. PMID: 28266545
- Polymorphisms in the ERα gene do not predict in vitro fertilization outcome. PMID: 29916276
- High ESR1 expression is associated with metastasis in breast cancer. PMID: 29187405
- The G/G XbaI genotype of the ESR1 gene is associated with breast cancer risk. PMID: 29893332
- miR-221 may impair the protective effect of estrogen in degenerated cartilaginous endplate cells by targeting estrogen receptor alpha. PMID: 29529124
- The study found that NAT1 and ESR1 expression were elevated in primary breast tumor samples compared to normal breast tissue samples, and in ER+ primary breast tumors compared to ER- tumors. The study suggests that NAT1 and ESR1 expression may share overlapping regulation. PMID: 29901116
- All patients without mutations detected by molecular barcode next-generation sequencing (MB-NGS) were confirmed to have no mutations by ddPCR. The study concluded that MB-NGS successfully detected ESR1 mutations in cfDNA with a higher sensitivity (0.1%) than conventional NGS and demonstrated clinical utility comparable to ddPCR. PMID: 28905136
- The study identified an association between specific genotypes at three ESR1 polymorphisms (rs2234693, rs6902771, rs7774230) and one ESR2 polymorphism (rs3020449) and the presence of metabolic syndrome in postmenopausal women. PMID: 30049354
- The study observed a higher frequency of ESR1 and PIK3CA mutations in plasma compared to serum in 33 MBC patients, suggesting that serum samples may not be the preferred source of cfDNA. PMID: 29689710
- The findings suggest that miR-125a-3p may function as a novel tumor suppressor in ER(+) breast cancer by targeting CDK3, potentially offering a therapeutic approach for TamR breast cancer therapy. PMID: 28939591
- A significant finding of the study revealed that 20% of patients with breast cancer bone marrow (BM) exhibited receptor discrepancy between the primary tumor and subsequent BM, with loss of hormone receptors (ER and/or PR) expression and gain of HER2 overexpression being the most common changes. PMID: 28975433
- The research highlights a pivotal role for IGF-IR in regulating ERalpha-positive breast cancer cell aggressiveness and the regulation of expression levels of several extracellular matrix molecules. PMID: 28079144
- The study explored the associations between PvuII (T>C) and XbaI (A>G) polymorphisms of the estrogen receptor alpha (ESR1) gene with type 2 diabetes mellitus (T2DM) or metabolic syndrome (MetS). PMID: 29883973
- The ERalpha gene appears to play a key role in stress urinary incontinence during the premenopausal period. PMID: 29769420
- The study reported the first discovery of naturally occurring ESR1 (Y537C) and ESR1 (Y537S) mutations in MCF7 and SUM44 ESR1-positive cell lines following acquired resistance to long-term estrogen deprivation (LTED) and subsequent resistance to fulvestrant (ICIR). These mutations accumulated over time, impacting ESR1 binding to the genome and altering the ESR1 interactome. PMID: 29192207
- Concomitant high expression of ERalpha36, GRP78, and GRP94 is associated with aggressive papillary thyroid cancer behavior and can serve as a predictor for extrathyroid extension, lymph node metastasis, and distant metastasis. PMID: 29368272
- Estrogen receptor-1 is a key regulator of HIV-1 latency and imparts gender-specific restrictions on the latent reservoir. PMID: 30061382
- Down-regulation of ESR1 gene expression was enhanced by the development of breast cancer. PMID: 29543921
- The study aimed to assess whether fibrosis markers, estrogen receptor (ER)alpha, and the stromal derived factor (SDF)1/CXC chemokine receptor type 4 (CXCR4) axis are abnormally expressed in the endometrium of patients with intrauterine adhesions. PMID: 29568895
- The frequency of alleles and genotypes of polymorphisms FSHR(-29G/A) and ESRI (XbaI A/G) in women with normal to poor response did not show significant correlation. PMID: 29526845
- Each estrogen receptor alpha and estrogen receptor beta gene polymorphism may have a differential impact on postmenopausal osteoporosis risk and bone mineral density across various ethnicities. PMID: 29458346
- The results suggest that the minor allele A of the ESR1 gene is associated with the development of arterial hypertension in men. PMID: 29658078
- The study found that tamoxifen treatment induced a decrease in PRMT2 and an increase in ER-alpha36 as well as ER-alpha36-mediated non-genomic effect in the MDA-MB-231 breast cancer cell line. PMID: 29620287
- ESR1 mutations are not associated with clinical resistance to fulvestrant in breast cancer patients. PMID: 27174596
- Overexpression of COPS5, through its isopeptidase activity, leads to ubiquitination and proteasome-mediated degradation of NCoR, a key corepressor for ERalpha and tamoxifen-mediated suppression of ERalpha target genes. PMID: 27375289
- ESR alpha PvuII and XbaI polymorphisms are not associated with systemic lupus erythematosus. However, the combination of the TC/AA and CC/GG genotypes was associated with SLE susceptibility. PMID: 29356461
- Estrogen receptor (ER) and progesterone receptor (PR) expression in endometrial carcinoma (EC) were significantly higher than those in the paracarcinoma tissue and control. PMID: 29081408
- ESR1 promoter methylation was identified as an independent risk factor and exhibited a high predictive value for 28-day mortality from acute-on-chronic hepatitis B liver failure. PMID: 29082740
- By analyzing different estrogen receptor-alpha(ER-a)-positive and ER-a-negative breast cancer cell lines, the study defined the role of CCN5 in the leptin-mediated regulation of growth and invasive capacity. PMID: 29370782
- This study identified ESR1 as a direct target of miR-301a-3p. PMID: 29763890
- Authors report for the first time the presence of ESR1 methylation in plasma ctDNA of patients with HGSC. The agreement between ESR1 methylation in primary tumors and paired ctDNA was statistically significant. PMID: 29807696
- This study reports the development of a novel class of ERa AF2 inhibitors, which have the potential to effectively inhibit ERa activity by a unique mechanism and to circumvent the issue of mutation-driven resistance in breast cancer. PMID: 29462880
- The P2X7R rs3751143 and ER-alpha PvuII two-locus interaction confers a significantly high susceptibility to osteoporosis in Chinese postmenopausal women. PMID: 28884379
- Alcohol consumption may have differential effects on concordant and discordant receptor subtypes of breast cancer. PMID: 29353824
- ERalpha and ERbeta mRNA expression was significantly higher (p < 0.05) in tumor tissues compared to their paired normal mucosa and correlated inversely with survival outcome. PMID: 29390981
- High ESR1 expression is associated with Papillary Thyroid Carcinoma. PMID: 28124274
- Oral administration of RAD140 substantially inhibited the growth of AR/ER(+) breast cancer patient-derived xenografts (PDX). Activation of the AR and suppression of the ER pathway, including the ESR1 gene, were observed with RAD140 treatment. PMID: 28974548
- Polymorphism in the ERalpha gene is associated with an increased risk for advanced Pelvic Organ Prolapse. However, polymorphism in the LAMC1 gene does not appear to be associated with such risk. PMID: 29241914
