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Immunohistochemical analysis of estrogen and progesterone receptors in fallopian tubes during ectopic pregnancy.

OBJECTIVE: To study decidualization, estrogen receptor (ER), and progesterone receptor (PR) expression in fallopian tubes containing an ectopic pregnancy (EP). DESIGN: Assessment of decidual reaction by light microscopy, staining of ER and PR in epithelium and stroma by immunohistochemical methods. SETTING: Academic hospital. PATIENTS: Twelve women with an ampullary located EP. INTERVENTION: A partial or complete tubal resection. RESULTS: Only minimal decidualization was observed in five tubes. Estrogen receptor expression was noted in glandular cells in seven tubes. No correlation was found between decidualization and ER staining. No PR expression was seen in glandular epithelium or in stroma. CONCLUSIONS: It is postulated that absence of PR is correlated to poor decidualization and to failure of treatment of EP with antiprogestins (RU486).

Decidua↗

Insulin-like growth factor I receptors in human corpora lutea.

OBJECTIVE: To determine the presence and binding characteristics of insulin-like growth factor (IGF) receptors in corpora lutea (CL) of spontaneous and clomiphene citrate (CC)-induced cycles and to identify any relationship between IGF receptors and cytosol progesterone (P) and 17 alpha-hydroxyprogesterone (17 alpha-OHP) levels. DESIGN: Women undergoing bilateral tubal ligation were divided into two groups. One group received no medication (controls) and the other took 50 mg of CC. Midluteal phase CL were recovered at tubal ligation for hormone and receptor analysis. SETTING: Patients were recruited from a university hospital setting. PATIENTS: Eleven fertile women 26 to 37 years of age requesting bilateral tubal ligation were studied. INTERVENTIONS: Four women were given 50 mg/d of CC from days 5 through 9 of study cycle. Seven women did not take any medication. Minilaparotomy bilateral tubal ligation and luteectomy were performed 7 to 9 days after midcycle urinary (LH) surge. MAIN OUTCOME MEASURES: Insulin-like growth factor receptor concentrations and binding characteristics and cytosol P and 17 alpha-OHP levels in individual CL. RESULTS: Optimal binding for 125I-IGF-I with membrane fractions of homogenized CL was obtained with incubation at 4 degrees C for 16 hours. Specific binding (mean +/- SEM) was significantly higher in CC-treated (53.6% +/- 4.8%) than in control cycles (25.9% +/- 5.5%, P less than 0.001). Receptor concentrations were also significantly higher in CL from CC-induced (145.6 +/- 21.8 pmol/mg protein) than from control cycles (74.8 +/- 15.2 pmol/mg protein, P less than 0.02). Insulin-like growth factor receptor levels correlated with neither serum nor cytosol P and 17 alpha-OHP in CL from either cycles. CONCLUSION: Specific IGF-I receptors are present in human CL of the menstrual cycle with higher concentrations present in CC-induced cycles. Thus IGF may express its action on luteal function through its receptors in CL.

Adult↗

The immunoendocrinology of estrophilin.

Immunoglobulin from the serum of rabbits immunized with highly purified estradiol-receptor complex from calf uterine nuclei has been shown to contain specific antibodies to estrophilin by five criteria. Antibodies to calf nuclear estrophilin cross react with nuclear estradiol-receptor complexes of rat, rabbit and sheep uterus, rat endometrial and pituitary tumor, and MCF-7 human breast cancer cell line. They also react with extranuclear receptor of calf, rat, mouse, rabbit, guinea pig, monkey and sheep uterus, rat mammary, endometrial and pituitary tumor, and human breast cancer. There is no interaction of the antibody with estradiol itself. The nuclear form of estrophilin appears to bind more immunoglobulin molecules than does the cytosol form. The antibodies do not react with either the nuclear or extranuclear dihydrotestosterone-receptor complexes of rat prostate, with the extranuclear progesterone-receptor complexes of rabbit uterus, chick oviduct or rat endometrial tumor, or with rat and mouse alpha-fetoprotein. These findings indicate an immunochemical similarity among estrophilins from several mammalian species, as well as between nuclear and extranuclear forms of the receptor, but not among receptor proteins for different steroid hormones. Immunoglobulin from the serum of a goat immunized with similar antigen shows a considerably higher titer of antibodies to estrophilin. These react with nuclear and extranuclear estradiol-receptor complexes of calf uterus to produce somewhat larger entities than those formed with the rabbit antibody. Unlike the rabbit antibody, interaction with the goat antibody causes a noticeable decrease in estradiol-binding affinity of the extranuclear estrophilin as well as an apparent decrease in the total hormone-binding capacity. Specific antibodies to estrophilin offer promise as valuable reagents for receptor analysis and purification, as well as for the elucidation of many still unresolved questions concerning receptor synthesis, localization and function.

Animals↗

[The pathogenesis of the "endometritis-pyometra complex" in the female dog].

Based on investigations in 51 bitches (uteri and ovaries after ovariohysterectomy), suffering from "endometritis-pyometra-complex" (without, n = 38; with, n = 13, hormonal pretreatment), morphologic-functional endometrial characteristics (light microscopy, scanning electron microscopy, enzyme histochemistry, immunohistochemical estrogen receptor analysis) are correlated with ovarian findings, plasma estradiol and progesterone levels as well as microbiological results. The estrous phase of all cycling patients was determined as "diestrus". Plasma estradiol and progesterone concentrations fluctuate within physiological variations. In all cases, not including those, pretreated with progestagen, histological signs of irregular hyperproliferation of uterine glands are obvious, closely related with enzyme histochemical aberrations and atypical endometrial estrogen receptor state. This is interpreted as indicative for prolonged periestrous estrogen induced effects, undergoing different stages of secretory transformation due to the species specific long lasting corpus luteum period. A comparable pathogenesis is supposed deriving from estrogen applications (e. a. after mismating) due to intensified hormonal stimulation and sensibilization of the endometrium, predisposing to ascendant infections by facultative pathogenic bacteria (e. a. E. coli, Streptococcus sp.). Patients without ovarian cyclicity, resulting from progestagen application, exhibit findings, that indicate hormonal imbalances: secretory hypertrophy, irregular regeneration, fibrous atrophy and rigid secretion, resembling those possibly occurring in women after long administration of oral contraceptives.

Animals↗

[Use of computer-assisted image analysis for the detection of immunohistochemical receptor status in breast cancer. Immunohistochemical densitometry receptor analysis--IRDA].

A method for the evaluation of the immunohistochemical staining score of steroid receptors in breast cancer using computer-based image analysis is presented. The optical density of tumour cell nuclei was measured using kryostat sections and, using a control section as reference, an objective threshold for specific staining was defined. In intensively stained sections, a good correlation with visual scoring was achieved, but in 9 out of 16 sections, which were regarded as receptor-negative by visual scoring, a specific receptor-positive staining was demonstrated by image analysis. Next to the percentage of positive cells (PP) and the mean staining intensity (SI), a histogram of the receptor concentration in positive nuclei was calculated. The method allows, besides an objective evaluation and documentation, an exact definition of a threshold for specific receptor measurement and furthermore shows the pattern of receptor concentration in the tumour cell nuclei. Hence, the method could contribute towards a more widespread use of immunohistochemical receptor analysis.

Breast↗

Ligand-binding domain of thyroid hormone receptors modulates DNA binding and determines their bifunctional roles.

We report here that the thyroid hormone receptors TR alpha and TR beta, and the retinoic acid receptor, RAR, can bind cooperatively to the thyroid hormone response elements (TRE) in both the presence and absence of ligand. Although the transcriptional synergism induced by such cooperative DNA binding could also be influenced by the position of the DNA-binding site on the promoter, the strength of the receptor-DNA interaction in the absence of the cognate ligand of each receptor was in general correlated with the repression activity. The strong-binding TRs, but not the weaker-binding RAR, allowed repression of a constitutive promoter. In addition, strong-binding receptors could repress transcriptional activation of weaker-binding receptors on the TRE. We also show here that the presence of thyroid hormone affects the cooperative DNA binding of TR beta to a TRE dimer by increasing the dissociation rate and decreasing the association rate of TR beta with the DNA. Hybrid receptor analysis revealed that receptor-DNA interaction and repressor activity are largely influenced by the ligand-binding domain of the receptor. We used deletion analysis to localize the sequences conferring a negative effect of thyroid hormone on TR beta binding to DNA and on receptor dimerization or oligomerization. Our data indicate that the ligand-binding domain of thyroid hormone receptors has an essential role in DNA binding and repressor functions, and that this domain exerts its effects by controlling receptor dimerization and oligomerization in the absence and presence of ligand.

Animals↗

Correlation between clinical response to hormone therapy and steroid receptor content in prostatic cancer.

Hormonal therapy is the dominating form of treatment for prostatic carcinoma. The majority of cases (80%) are well controlled for varying times with this regimen. However, thus far there have been no adequate methods to predict in which cases hormonal therapy is of less benefit. Measurement of cancer tissue content of intracellular hormone receptors constitutes progress toward a more individualized therapy in prostatic carcinoma. In this study biopsies from 16 cancer patients were taken before therapy was given, and the specimens were analyzed with regard to content of specific methyltrienolone-binding sites. A correlation has been made between receptor content and clinical response to hormonal therapy in each case. Twelve specimens contained measurable amounts of steroid receptors. Of these, one patient died during irradiation therapy before onset of hormonal treatment. However, of the remaining 11 patients, 9 responded well to hormones (9/11 approximately 82%). The two receptor-positive nonresponders had the lowest measurable receptor levels in the series. Four specimens contained no detectable amounts of receptors. Three of these patients showed no response to therapy (3/4 = 75%) but one was "false negative." Our data indicate that steroid receptor analysis may become a valuable diagnostic tool in individualizing the therapy for prostatic cancer.

Aged↗

Steroid receptor content in human prostatic carcinoma and response to endocrine therapy.

Biopsy material from primary prostatic carcinoma from 25 patients was analyzed with regard to cytosol content of methyltrienolone (a synthetic androgen) binding sites and the receptor content has been correlated to the clinical response to endocrine therapy. A dextran-coated charcoal technique was used and binding data were calculated from Scatchard plots. In 20 of the tumors detectable levels of methyltrienolone receptor were noted. One of the receptor-positive patients died during radiation therapy before onset of hormonal treatment, and a second patient, who had a highly differentiated carcinoma, so far has not received any endocrine therapy. Of the remaining 18 patients 15 responded well to castration, treatment with estrogens, or Estracyt (approximately 80%). The biopsies from two of the three receptor-positive non-responders contained the lowest measurable receptor levels. Five specimens lacked detectable amounts of methyltrienolone receptor. Four of these patients did not respond to therapy (approximately 80%), but one was "false" negative. Our data indicate that steroid receptor analysis may become an important tool in predicting the value of endocrine therapy in human prostatic carcinoma.

Aged↗

Effects of thyroid hormone on myocardial adrenergic beta-receptor responsiveness and function during late gestation.

To assess the effect of fetal hypothyroidism during late gestation on postnatal cardiovascular responsiveness, we measured heart rate and cardiac output responses to isoproterenol in newborn lambs. To evaluate the effect of such altered thyroid status on the development of beta-adrenergic signaling cascade, we measured myocardial beta-adrenergic receptor concentration and affinity, guanine nucleotide regulatory protein density, and adenylyl cyclase responsiveness. Twenty fetal lambs underwent either thyroidectomy and line placement or line placement alone at 128-130 d gestation. Five thyroidectomized and six control newborns were treated with isoproterenol, five thyroidectomized and four control newborns were killed upon delivery and tissue was obtained for biochemical studies, and four additional animals were delivered and killed at 126 d gestation and tissue was obtained for receptor analysis. Of the newborns treated with isoproterenol, the thyroidectomized lambs showed lower increase in heart rate and cardiac output compared with euthyroid newborns. Compared with the myocardium of normal newborns of similar gestation, the myocardium of the newborns who underwent fetal thyroidectomy failed to show the normal increase in beta-adrenoceptors accompanied by reduction in beta-adrenergic-stimulated adenylate cyclase activity. These results suggest that near term, the normal development of ovine fetus myocardial beta-adrenergic receptor is affected by thyroid hormones.

Adenylyl Cyclases↗

Expression of recombinant human follicle-stimulating hormone receptor: species-specific ligand binding, signal transduction, and identification of multiple ovarian messenger ribonucleic acid transcripts.

The ligand specificity and biochemical properties of the human (h) FSH receptor are poorly characterized due to the low abundance of these receptors and the limited availability of human tissues. Using a fragment of rat FSH receptor cDNA, we screened a human testicular cDNA library and obtained a FSH receptor cDNA covering the entire amino acid-coding region. After transfection of a human fetal kidney cell line (293) with the hFSH receptor cDNA, radioligand receptor analysis revealed the presence of high affinity (Kd, 1.7 x 10(-9) M) FSH-binding sites on the plasma membrane. Both recombinant and wild-type hFSH displaced [125I]hFSH binding, with ED50 values of 25 and 70 ng/ml, respectively, whereas hLH, hCG, and hTSH were ineffective. Although human, rat(r), and ovine FSH as well as equine CG competed for rat testicular FSH receptor binding, only hFSH and rFSH interacted effectively with the recombinant hFSH receptor, suggesting that species-specific ligand recognition exists between human and rodent receptors. After incubation of transfected cells with hFSH, but not recombinant hLH or hCG, a dose-dependent increase (ED50, 10 ng/ml) in extracellular cAMP accumulation was observed, indicating a functional coupling of the expressed human receptor with the endogenous adenyl cyclase. In cells cotransfected with the FSH receptor expression plasmid and a luciferase reporter gene driven by the promoter of a cAMP-responsive gene, treatment with hFSH, but not hCG, resulted in a dose-dependent increase in luciferase activity. Northern blot analysis using a cRNA probe derived from the human receptor cDNA indicated the presence of multiple FSH receptor mRNA transcripts (7.0, 4.2, and 2.5 kilobases) in RNA prepared from human follicular phase ovary, but not from human corpus luteum or placenta. Additionally, two FSH-binding sites of 76 and 112 kilodaltons were detected in transfected 293 cells after ligand/receptor cross-linking and sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis. These results demonstrate the expression of functional hFSH receptor with unique ligand specificity and provide new data on the biochemical properties of the human receptor at the mRNA and protein levels.

Animals↗

Characterization of angiotensin-II receptor subtype on bovine thecal cells and its regulation by luteinizing hormone.

In this study the primary objectives were to localize angiotensin-II (AII) receptors on specific ovarian cells and determine whether these receptors are regulated by LH. AII receptor analysis, carried out using membrane fractions prepared from isolated thecal, granulosa, and luteal cells from bovine ovary, revealed that [125I]AII-binding sites were present only on thecal cells. The Kd and binding capacity were determined to be 0.29 +/- 0.08 nM and 66.9 +/- 8.1 fmol/mg membrane protein (mean +/- SEM from three experiments, each with duplicate determinations), respectively. None of the peptides unrelated to AII affected the binding of [125I]AII. Unlabeled AII, saralasin, and AIII were equipotent (IC50, approximately 5 nM for all three peptides) in competing with the radioligand. However, the binding affinity for AI was less by almost 2 log units. Using AII receptor subtype-specific nonpeptide antagonists, Losartan [a selective antagonist for the type 1 AII (AT1) receptor] and PD 123319 [a selective antagonist for the type 2 AII (AT2) receptor], AII receptors on thecal cells could be classified pharmacologically as AT2-type receptors. The IC50 determined from the competitive binding inhibition experiments for the various unlabeled competing substances were 5 nM, 20 nM, 200 nM, and 200 microM with respect to AII, p-amino-phenylalanine-AII, PD123319, and Losartan, respectively. Thecal cells cultured in a serum-free medium also expressed AII receptors, which could be up-regulated by LH or 8-bromo-cAMP in a dose-dependent manner. The number of AII receptors on thecal cells nearly doubled when the cells were cultured in the presence of 100 ng/ml LH, with little change in their Kd value. This increase in the number of AII receptors was inhibitable by a protein synthesis inhibitor, cycloheximide. In summary, we have demonstrated that in the bovine ovary, AII receptors belonging to AT2 subclass are predominantly expressed on thecal cells, and these receptors can be up-regulated by LH via a cAMP-dependent mechanism. Thus, the bovine thecal cells in primary culture can potentially become a useful in vitro system to study the mechanism of regulation of AII receptor induction as well as the so far unknown function of this class of receptor.

8-Bromo Cyclic Adenosine Monophosphate↗

Design and synthesis of a novel biotinylated photoreactive insulin for receptor analysis.

B1-(4-Azido-salicyloyl)-[B1-biocytin,B2-lysine]insulin was synthesized by double Edman degradation of A1,B29-Msc2-insulin and stepwise acylation at the N-terminus of the B-chain. This derivative is homogeneous in RP-HPLC and has a biological in vitro activity of 20% and receptor binding of 15%, relative to insulin. Radioiodination and HPLC gave the B1-labelled 125I-derivative (I) as well as the 4 isomers with 125I-labelled tyrosine (A14, A19, B16, B26). UV-induced crosslinking of I with insulin receptors led to specific labelling of the alpha-subunit (Mr 130,000). The peptide bond LysB2-AspB3 is completely cleavable by trypsin (EC 3.4.21.4). I is thus a new tool for the analysis of the hormone-binding region by making possible the isolation of tryptic, biotinylated receptor fragments labelled by the dipeptide 125I-4-azidosalicyloyl-biocytinyl-Lys.

Affinity Labels↗

LH-RH receptors in the human pancreas. Basis for antihormonal treatment in ductal carcinoma of the pancreas.

LH-RH-, estrogen-, and progesterone-receptor binding was measured in the human pancreas of patients with ductal pancreatic cancer (n = 23) and chronic pancreatitis (n = 15), and of organ donors (n = 11). Receptor analysis was determined by incubation of the homogenized tissues with estrogen, progesterone, and the LH-RH analog buserelin labeled with iodine-125. Only one biopsy (9%) from normal pancreas had an LH-RH-receptor concentration greater than 3 fmol/mg membrane protein. LH-RH binding levels greater than 3 fmol/mg were detected in 67% of patients with chronic pancreatitis and in 57% of patients with pancreatic cancer. Progesterone levels greater than 15 fmol/mg membrane protein were found in 36% of normal pancreas, in 27% of chronic pancreatitis, and in 17% of pancreatic cancer cases, respectively. The highest concentration of estrogen receptors (greater than 15 fmol/mg membrane protein) was seen in normal pancreas (73%). The increase in LH-RH-receptor concentration in chronic pancreatitis and pancreatic cancer seems to be unspecific, but might be of benefit for antiproliferative treatment in pancreatic cancer.

Adult↗

Estradiol receptor analysis in human breast cancer tissue by isoelectric focusing in polyacrylamide gel.

Isoelectric focusing in polyacrylamide gel combined with limited proteolysis is a simple and specific method for quantitation of estradiol receptors in breast cancer tissue. At least eight different samples can be analyzed simultaneously on one gel, and the whole procedure, including sample preparation, takes less than 7 hr. In comparison with sucrose gradient centrifugation, isoelectric focusing is more sensitive, possibly due to the short time (1.5 to 2 hr) needed for the analysis. Furthermore, only one incubation with tritium-labeled estradiol is needed for an analysis, which means that a smaller amount of tumor tissue is needed than for most other methods. This fact allows analysis of the estrogen receptor content in tumor material obtained from fine-needle biopsy.

Breast Neoplasms↗

The NSILA-s receptor in liver plasma membranes. Characterization and comparison with the insulin receptor.

NSILA-s (nonsuppressible insulin-like activity, soluble in acid ethanol) is a serum peptide that has insulin-like and growth-promoting activities. We have demonstrated previously that liver plasma membranes possess separate receptors for NSILA-s and insulin and have characterized the insulin receptor in detail. In the present study we have characterized the properties and specificity of the NSILA-s receptor and compared them to those of the insulin receptor in the same tissue. Both 125I-NSILA-s and 125I-insulin bind rapidly and reversibly to their receptors in liver membranes; maximal NSILA-s binding occurs at 20 degrees while maximal insulin binding is seen at 1-4 degrees. The pH optimum for NSILA-s binding is broad (6.0 to 8.0), in contrast to the very sharp pH optimum (7.5 to 8.0) for insulin binding. Both receptors exhibit a high degree of specificity. With the insulin receptor, NSILA-s and insulin analogues compete for binding in proportion to their insulin-like potency: insulin greater than proinsulin greater than NSILA-s. With the NSILA-s receptor, NSILA-s is most potent and the order is reversed: NSILA-s greater than proinsulin greater than insulin. Furthermore, six preparations of NSILA-s which varied 70-fold in biological activity competed for 125I-NSILA-s binding in order of their potencies. NSILA-s which had been inactivated biologically by reduction and aminoethylation and growth hormone were less than 1/100,000 as potent as the most purified NSILA-s preparation. Purified preparations of fibroblast growth factor, epidermal growth factor, nerve growth factor, and somatomedins B and C were less than 1% as effective as NSILA-s in competing for the 125I-NSILA-s suggesting that these factors act through other receptors. In contrast, somatomedin A was 10% as active as NSILA-s and multiplication-stimulating activity was fully as active as NSILA-s in competing for the NSILA-s receptor. Analysis of the data suggests that there are approximately 50 times more insulin receptors than NSILA-s receptors per liver cell, while the apparent affinity of NSILA-s receptors is somewhat higher than that of the insulin receptor.

Animals↗