Sulfhydryl sensitivity and [125I]-16 alpha-IODO-17 beta-estradiol binding of estrogen receptor in ovarian epithelial carcinomas

Prognostic and diagnostic implications of estrogen and progesterone receptor assays in cytology

Scientific evidence suggests that cancer is a consequence of genetic changes that result in uncontrolled cellular growth, tissue invasion, and metastasis. This concept has led to a great deal of excitement in the medical community in the hope that precise identification of genes involved in human cancer could potentially facilitate our understanding of human malignancies. It may also be possible to apply this information directly to different clinical settings. Many technologies are now available which offer opportunities for pathologists to not only expand their diagnostic abilities, but also to assess the prognosis of a given tumor in a specific patient. These include immunocytochemistry, flow cytometry, cell image analysis, and molecular genetic studies. In this review, the role of immunocytochemical hormone receptor assay as an aid in tumor prognosis and in prediction of tumor response to endocrine therapy will be discussed. Emphasis will be placed on the use of hormone receptor assay as an adjunct in diagnostic pathology and in assessment of metastatic tumors of unknown origin. The potential value of assessment of hormone receptors in different cytologic preparations will also be discussed.

Comparison of the quantity of estrogen receptors in human endometrium and myometrium by steroid-binding assay and enzyme immunoassay based on monoclonal antibodies to human estrophilin

The recently developed enzyme immunoassay for estrogen receptors is more simple to perform with quality assurance than conventional steroid-binding assays with radioactive labeled estrogen. However, it is not known how well the results of the two assays agree for normal human uterine samples. We compared enzyme immunoassay (Abbott estrogen receptor enzyme immunoassay) and steroid-binding assay of normal human endometrium and myometrium. Low-salt, "cytosol" estrogen receptor determinations were performed by dextran-coated charcoal assay, and high-salt, "nuclear" estrogen receptors were measured by controlled pore glass bead assay. Results showed excellent correlation (p less than 0.0001) for cytosol estrogen receptor of endometrium (r = 0.95) and myometrium (r = 0.79) and also for a smaller number of nuclear estrogen receptors of myometrium (p less than 0.01, r = 0.69). Good agreement between steroid-binding assay and enzyme immunoassay was seen for estrogen receptors of both proliferative and secretory phase samples. Thus the data indicate that the simpler estrogen receptor enzyme immunoassay is useful to measure estrogen receptor in the normal uterus. Furthermore, with this sandwich assay, there is no evidence for the existence of significant quantities of receptor fragments that do not bind estrogen.

The predictive value of steroid hormone receptor analysis in breast, endometrial and ovarian cancer

The predictive value of female sex steroid, estrogen and progesterone, receptor (ER and PR, respectively) assays in breast, endometrial and ovarian cancer is reviewed with emphasis on comparative aspects of these malignant tumors in relation to their hormone dependency. The endocrine etiology of these three tumor types seems to be at least partly different, and so is the expression of these receptors in normal and malignant tissues of the breast, endometrium and ovary. There is a tendency for decreased receptor concentrations and disappearance of these receptors in association with advancement of these malignancies. There is also a decrease in the presence and concentrations of ER and PR in relation to loss of differentiation in breast and endometrial cancer. Receptor analyses have an established position in the selection of patients with advanced breast cancer for endocrine treatment, and they give promise of a similar application in endometrial cancer and in endometrioid cancer of the ovary. It is not clear whether the disease-free interval is related to the presence or concentrations of ER or PR as such in the tumor tissue. There is better survival in breast cancer patients with receptor-positive tumors, which might be due to a response to endocrine treatment. The same seems to be true for patients with endometrial cancer. Future progress in the application of female sex steroid receptor analyses in breast, endometrial and ovarian cancer needs additional controlled clinical trials and more highly developed receptor assays.

Binding of estrogen receptor from N-nitrosomethylurea-induced rat mammary tumors to nuclei

The binding of the cytoplasmic estrogen receptor (ERc) from N-nitrosomethylurea (NMU)-induced rat mammary tumors to the nucleus using a cell-free system is described. All tumors studied were estrogen-receptor-positive and most of them were hormone-dependent. Sixty-two percent of all tumors investigated (n = 134) decreased in size more than 30% 4-5 days after ovariectomy. Brief heating of the cytosol loaded with tritiated estradiol induced activation of the ERc measured by an increase of nuclear binding activity. Temperature-dependent activation was evident in every case. The optimal time and temperature of activation were 15-60 min at 30 degrees C. After denaturation of the ERc by heating for 20 min at 56 degrees C only small parts of free estradiol could be bound to nuclei. Mg2+ ions and EDTA inhibited the nuclear binding of the receptor. The nuclear binding assay was performed for 1 hr at 0-4 degrees C. After this time the activated ERc was bound nearly maximally to nuclei. Under optimized conditions 50-60% of the ERc could be bound to nuclei maximally. Using the same medium for the preparation of crude and purified nuclei the binding of the receptor to both kinds of nuclei was similar. Na2MoO4 prevented the activation of the ERc from NMU-tumors completely but did not influence the binding of the previously activated receptor to nuclei.

The synthesis of non-steroidal estrogen receptor binding compounds labeled with 80mBr

Estrogen receptor (ER) binding radiopharmaceuticals have potential for use in the diagnosis and treatment of cancers of the female reproductive system. Two triphenylethylene derivatives based on the structure of hydroxytamoxifen 4, a high ER binding metabolite of tamoxifen 5, have been prepared: 1-(4-dimethylaminoethoxy)phenyl]-1-(4-hydroxy)phenyl-2-bromo-2-phenyl ethylene 2 and 1,1-bis (p-hydroxyphenyl)-2-bromo-2-phenylethylene 3. Both 2 and 3 bind strongly to the ER. Compound 3 has been labeled in modest yield by direct bromination with 80mBr, which was produced by the 83Kr (d,n alpha) reaction. Radiolabeled 22, a dimethoxy precursor of 3, has been prepared in yields ranging between 40 and 60% by a bromination destannylation reaction.

A controlled pore glass bead assay for the measurement of cytoplasmic and nuclear glucocorticoid receptors

An assay for the quantitation of cytoplasmic and nuclear glucocorticoid receptors in lymphoid tissue has been developed using controlled pore glass (CPG) beads. Soluble receptor--3H-steroid complex (cytosol or nuclear extract) is adsorbed quantitatively within the crevasses of porous glass beads. Excess labeled steroid as well as most non-specifically bound steroid is easily washed away, leaving the hormone-receptor complex retained by the beads. Bound 3H-steroid is eluted with ethanol and measured for radioactivity. This procedure which is simple, rapid, and highly reproducible is carried out using frozen samples (stable for many months) containing as few as 1 X 10(7) cells. A comparison of the CPG assay to dextran coated charcoal and a whole cell assay demonstrates that CPG and dextran coated charcoal give equivalent measurements of cytosolic receptor concentration, while the CPG and whole cell assays provide equivalent values for total receptor content.

The use of a hydroxylapatite-filter steroid receptor assay method in the study of the modulation of androgen receptor interaction

Receptors for androgen, estrogen, and glucocorticoid can be assayed by hydroxylapatite adsorption of the radioactive steroid-receptor complex and washing of the adducts on membrane filters mounted on a multiple filter holder. The method is economical, very rapid and sensitive. This new receptor assay method was used to study the modulation of androgen receptor of rat ventral prostate by metal ions, thiols, and ligand structure. The interaction of androgen with the naked receptor is inhibited by 10 microM ZnCl2, CdSO4, or CuSO4 but this inhibition is competed by androgen and is reversed by DTT. The androgen-receptor complex is less sensitive to divalent metal ions but Zn2+, at 3 mM, appears to alter the conformation of the receptor and promote the release of androgen. Certain phenanthrene derivatives exhibited striking structural specificities in their ability to compete with radioactive androgen for binding to the prostate receptor. The results suggest that the receptor has binding preference toward individual ring structure in the steroid.

Cytosol and nuclear estrogen and progestin receptors and 17 beta-hydroxysteroid dehydrogenase activity in non-diseased tissue and in benign and malignant tumors of the human ovary

Significant but low concentrations (mean 8 fmol/mg cytosol protein) of cytosol estrogen receptors were found in 57% of non-diseased ovarian tissues, and higher concentrations (mean 211) of cytosol progestin receptors in all these tissues. An approximately similar distribution was found for the presence of nuclear female sex steroid receptors; the mean concentrations were 159 and 1149 sites/cell, for estrogen and progestin receptors, respectively. There were no major differences in these parameters between pre- and postmenopausal non-diseased ovaries. The activities of ovarian 17 beta-hydroxysteroid dehydrogenase (17-HSD) did not display correlations between circulating progesterone concentrations in pre- or postmenopausal women with non-diseased ovaries. The majority of benign epithelial tumors contained significant concentrations of cytosol estrogen receptors, and all showed cytosol progestin receptors. The concentration of estrogen receptors was identical to that seen in non-diseased ovaries (mean 9 fmol/mg cytosol protein), whereas that of progestin receptor was significantly lower (mean 95). Nuclear female sex steroid receptors were measured in all benign tumors, and their concentrations were significantly higher than in normal ovaries (440 and 3218 sites/cell for estrogen and progestin receptors, respectively). No difference in 17-HSD activities were detected between normal ovaries and benign tumors. In malignant ovarian tumors, the picture was different from that found in normal ovarian tissues and benign tumors. Cytosol estrogen receptor was found in 89% of malignant epithelial tumors, and its concentration was significantly higher (mean 64 fmol/mg cytosol protein). Cytosol progestin receptor was found in 91%, and its concentration (mean 75) was significantly lower than in normal ovarian tissue or benign ovarian tumors. Nuclear female sex steroid receptor concentrations were intermediate between those seen in non-diseased ovaries an in benign tumors. 17-HSD activity was significantly lower than in other tissue categories studied. In the small group (16) of non-epithelial ovarian carcinomas cytosol estrogen receptors were not found, whereas the results of other measurements did not display any coherent picture. Breast and endometrial carcinoma metastatic to the ovary showed receptor patterns which were typical of the primary tumors. When the different clinical stages (I-IV) of malignant epithelial ovarian tumors were compared, 17-HSD activity was significantly higher in the least advanced clinical stage (I), whereas no significant differences were found in the other parameters measured.(ABSTRACT TRUNCATED AT 400 WORDS)

Binding of [3H] monohydroxytamoxifen in ovarian carcinoma

A monoclonal antibody (D-547) against human breast cancer oestrogen receptor was used to demonstrate that the oestrogen receptor in ovarian epithelial carcinomata binds [3H]monohydroxytamoxifen. This binding was observed in sedimentation velocity analyses of both cytosol and nuclear compartments. Binding of [3H]monohydroxytamoxifen to the antibody-recognized moiety could be inhibited by diethylstilboestrol or oestradiol, but not by androgen, progestin or corticoid, indicating oestrogen specificity for the binding site. The sedimentation coefficient of the antibody-recognized [3H]monohydroxytamoxifen binding moiety was similar to that when 16 alpha-[125I]iodo-oestradiol was used as the ligand.