The lability of estrogen receptor: correlation of estrogen binding and immunoreactivity.

Abstract We compared the Abbott enzyme immunoassay method for estrogen receptor with a standard dextran-coated charcoal method, and studied the effects of treatments causing denaturation. Estrogen receptor values were slightly higher by the Abbott method, but the methods agreed with regard to receptors being present or absent in 94-98% of 50 cases. Heat lability of immunoreactivity by the Abbott enzyme immunoassay is comparable to the lability of estrogen binding by the estrogen receptor. Estrogen and molybdate substantially stabilized estrogen receptor during the assay, but improper handling of tissue before the assay may cause similar, substantial decreases in estrogen receptor by either method. The Abbott method is easier to use than the dextrancoated charcoal method, requires less tissue, and measures receptor with or without endogenously bound estrogen, but reagent cost is high.

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Determination of Estrogen Receptors in Human Breast Cancer: Comparison between Enzyme Immunoassay and Dextran-Coated Charcoal Method

Tumori Journal ◽

10.1177/030089168607200511 ◽

1986 ◽

Vol 72 (5) ◽

pp. 511-514 ◽

Cited By ~ 3

Author(s):

Cecilia Bozzetti ◽

Nadia Naldi ◽

Annamaria Guazzi ◽

Rita Nizzoli ◽

Magda Benecchi ◽

...

Keyword(s):

Breast Cancer ◽

Estrogen Receptor ◽

Estrogen Receptors ◽

Enzyme Immunoassay ◽

Strong Correlation ◽

Human Breast Cancer ◽

Human Breast ◽

Dextran Coated Charcoal ◽

The Mean

Estrogen receptor determination was performed on 120 breast cancer cytosols, using the dextran-coated charcoal method (DCC) and an enzyme immunoassay (EIA) to compare the efficiency of the two techniques. A strong correlation was noted between ER concentrations determined by DCC and EIA (P < 0.001). The mean ER-EIA value was significantly higher than the mean ER-DCC value in premenopausal (P < 0.001) as well in postmenopausal (P < 0.001) patients.

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A second estrogen receptor from Japanese lamprey (Lethenteron japonicum) does not have activities for estrogen binding and transcription

General and Comparative Endocrinology ◽

10.1016/j.ygcen.2016.07.014 ◽

2016 ◽

Vol 236 ◽

pp. 105-114 ◽

Cited By ~ 7

Author(s):

Yoshinao Katsu ◽

Paul A. Cziko ◽

Charlie Chandsawangbhuwana ◽

Joseph W. Thornton ◽

Rui Sato ◽

...

Keyword(s):

Estrogen Receptor ◽

Estrogen Binding

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Estrogen Receptor-Independent Catechol Estrogen Binding Activity: Protein Binding Studies in Wild-Type, Estrogen Receptor-α KO, and Aromatase KO Mice Tissues†

Biochemistry ◽

10.1021/bi036154j ◽

2004 ◽

Vol 43 (21) ◽

pp. 6698-6708 ◽

Cited By ~ 17

Author(s):

Brian J. Philips ◽

Pete J. Ansell ◽

Leslie G. Newton ◽

Nobuhiro Harada ◽

Shin-Ichiro Honda ◽

...

Keyword(s):

Estrogen Receptor ◽

Protein Binding ◽

Estrogen Receptor Α ◽

Binding Activity ◽

Wild Type ◽

Binding Studies ◽

Catechol Estrogen ◽

Estrogen Binding

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Estrophilin immunoreactivity versus estrogen receptor binding activity in meningiomas: Evidence for multiple estrogen binding sites

Surgical Neurology ◽

10.1016/0090-3019(87)90131-5 ◽

1987 ◽

Vol 28 (3) ◽

pp. 181-188 ◽

Cited By ~ 6

Author(s):

K.P. Lesch ◽

W. Schott ◽

S. Gross

Keyword(s):

Estrogen Receptor ◽

Receptor Binding ◽

Binding Sites ◽

Binding Activity ◽

Estrogen Receptor Binding ◽

Receptor Binding Activity ◽

Estrogen Binding

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Antioxidants and Gene Regulation: The Effects of Vitamins C and E on Estrogen Receptors

Elements ◽

10.6017/eurj.v2i1.8970 ◽

2006 ◽

Vol 2 (1) ◽

Author(s):

Jeong Ho Nam

Keyword(s):

Breast Cancer ◽

Nitric Oxide ◽

Estrogen Receptor ◽

Breast Cancer Cells ◽

Past Research ◽

Receptor Expression ◽

Cancer Development ◽

Nitric Oxide Release ◽

Gene Level ◽

Estrogen Binding

Research shows that estrogen binding to its receptor plays a role in breast cancer development and that antioxidants possibly mitigate this effect. Past research examined whether various treatments lead to accelerated cell division, but characterization and comparison of the effects of different treatments on gene level expression of the receptor was not accomplished. Initially, the effect of antioxidants on the estrogen receptor expression was investigated, revealing the presence of Vitamins C and E on nitric oxide release (a possible cancer reduction agent) stimulated by estrogen acting on the surface estrogen receptor of breast cancer cells was observed. Generally, Vitamin E was most effective for improving nitric oxide release.

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Evaluation of an enzyme immunoassay kit for estrogen receptor measurement--report II.

Clinical Chemistry ◽

10.1093/clinchem/34.10.2053 ◽

1988 ◽

Vol 34 (10) ◽

pp. 2053-2057 ◽

Cited By ~ 2

Author(s):

S Raam ◽

D M Vrabel

Keyword(s):

Enzyme Immunoassay ◽

Binding Sites ◽

Solid Phase ◽

Functional Characterization ◽

Quantitative Agreement ◽

Type I ◽

Type Ii ◽

Immunoreactive Protein ◽

Estrogen Binding

Abstract We present evidence to show that monoclonal antibodies to estrogen receptors (ER) in solid phase recognize the secondary estrogen binding sites with moderate to low affinity for estradiol (E2). An excellent quantitative agreement was found in five cytosols between the ER values obtained by the enzyme immunoassay (ER-EIA) and the amount of secondary estrogen binding sites measured by the assay involving dextran-coated charcoal (Clin Chem 1986;32:1496). The immunoreactive protein recognized by the antibody-coated beads, when allowed to react with ER(+) cytosols, is shown to bind [3H]estradiol only when the ligand concentration exceeds 8 nmol/L. Further biochemical and functional characterization of the immunoreactive protein is required to establish similarities/dissimilarities between this protein, high-affinity Type I ER sites, and the secondary sites such as Type II sites.

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Involvement of estrogen receptors α and β in the regulation of cervical permeability

AJP Cell Physiology ◽

10.1152/ajpcell.2000.278.4.c689 ◽

2000 ◽

Vol 278 (4) ◽

pp. C689-C696 ◽

Cited By ~ 20

Author(s):

George I. Gorodeski ◽

Dipika Pal

Keyword(s):

Estrogen Receptor ◽

Binding Sites ◽

Estrogen Receptor Α ◽

Binding Activity ◽

Scatchard Analysis ◽

Single Class ◽

Estrogen Receptor Modulators ◽

Transcription Inhibitor ◽

Estrogen Binding ◽

In Cells

Estrogen increases the permeability of cultured human cervical epithelia (Gorodeski, GI. Am J Physiol Cell Physiol 275: C888–C899, 1998), and the effect is blocked by the estrogen receptor modulators ICI-182780 and tamoxifen. The objective of the study was to determine involvement of estrogen receptor(s) in mediating the effects on permeability. In cultured human cervical epithelial cells estradiol binds to high-affinity, low-capacity sites, in a specific and saturable manner. Scatchard analysis revealed a single class of binding sites with a dissociation constant of 1.3 nM and binding activity of ∼0.5 pmol/mg DNA. Estradiol increased the density of estrogen-binding sites in a time- and dose-related manner (half time ≈ 4 h, and EC50≈ 1 nM). RT-PCR assays revealed the expression of mRNA for the estrogen receptor α (αER) and estrogen receptor β (βER). Removal of estrogen from the culture medium decreased and treatment with estrogen increased the expression of αER and βER mRNA. In cells not treated with estrogen, ICI-182780 and tamoxifen increased βER mRNA. In cells treated with estrogen, neither ICI-182780 nor tamoxifen had modulated significantly the increase in αER or βER mRNA. The transcription inhibitor actinomycin D blocked the estrogen-induced increase in permeability, and it abrogated the estradiol-induced increase in estrogen binding sites. These results suggest that the estrogen-dependent increase in cervical permeability is mediated by an αER-dependent increase in transcription.

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Adaptation of "EMIT" technique for serum phenobarbital and diphenylhydantoin assays to the miniature centrifugal analyzer.

Clinical Chemistry ◽

10.1093/clinchem/22.6.905 ◽

1976 ◽

Vol 22 (6) ◽

pp. 905-907 ◽

Cited By ~ 11

Author(s):

S D Brunk ◽

T P Hadjiioannou ◽

S I Hadjiioannou ◽

H V Malmstadt

Keyword(s):

Gas Chromatography ◽

Enzyme Immunoassay ◽

Reaction Rates ◽

Anticonvulsant Drugs ◽

Rate Measurement ◽

Serum Samples ◽

Analytical Recovery ◽

Reagent Cost ◽

Measurement Mode ◽

Multiple Samples

Abstract We used a miniature centrifugal analyzer in a spectrophotometric rate-measurement mode to determine the anticonvulsant drugs phenobarbital and diphenylhydantoin in serum, by use of a modified enzyme immunoassay ("EMIT", Syva Corp.) We decreased reagent cost per determination by at least sixfold by means of microscale techniques. Also, the analysis rate is increased by measuring multiple samples simultaneously. Our method requires only 3 mul of serum for duplicate determinations. Replicate analyses of sera containing phenobarbital and diphenylhydantoin gave reaction rates with a CV of 1.5%. Run-to-run CV was 15%. Analytical recovery for drug-supplemented serum samples was 98%, and results for a series of samples compared well with results obtained by gas chromatography (for phenobarbital, r = 0.95; for diphenylhydantoin, r = 0.91).

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