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Results for “Hormone Receptors--analysis”

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PubMed1992

[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↗
PubMed1992

[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↗
PubMed1991

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↗
PubMed1978

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↗
PubMed1979

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↗
PubMed1990

[Steroid receptors and atypical histology as prognostic parameters in meningioma].

Cytosolic oestrogen and progesterone receptors (ER and PR) were determined in 58 primary and 13 recurrent meningiomas and related to their histological and clinical features. ER levels were low or not detectable (range 0-34 fmol/mg prot., median 0 fmol), whereas considerable amounts of PR were found in 69% of primary tumours (range 0-583 fmol/mg prot., median 72 fmol) and in 5/5 long-term recurrences (range 69-505 fmol/mg prot., median 143). Eight tumours recurred within a short-term period (less than 5 years) with a low PR expression (range 0-34 fmol/mg prot., median 0 fmol) and all presented raised cellularity and mitotic rate ("atypical" meningioma) or criteria of definitely malignant meningioma. The primary tumours of the short-term recurrences were not available for receptor analysis; however, they also were either "atypical" or anaplastic meningiomas. Long-term recurrences never displayed other than classical histology. From our results we conclude that polymorphy, as well as a lack of PR are strong indicators for short-term recurrence.

Brain↗
PubMed1990

Male breast cancer--a 20-year review of 16 cases at Yonsei University.

Sixteen cases of male breast cancer seen over a 20-year period were reviewed. The causes of cancer of the male breast are no better understood, but major alterations in hormonal environment could be a significant factor. Some clinical characteristics correspond well with the results of other series. The median age at presentation was 61.7 years. The most frequent initial symptom was a painless mass, and the incidences of nipple discharge, central tumor location, and axillary node involvement were high. Males also had a higher incidence of local advancement which was associated with a longer delay in seeking treatment and small breast tissue. The pathologic type was infiltrating ductal type in all cases except one, and all cases showed favorable nuclear grade. Estrogen receptor analysis was performed from the tumor of 2 patients. Both of them showed a high receptor level. There was no locoregional relapse in 5 patients who received adjuvant radiotherapy in contrast to the 2 relapses in 3 patients who underwent surgery alone. And three of the five patients who received radiotherapy suffered from systemic metastasis which suggested the important role of adjuvant chemotherapy as well as radiotherapy. In light of the encouraging results about adjuvant chemotherapy in the treatment for female breast cancer with axillary lymph node involvement, it would be desirable to extend this policy to male breast cancer.

Adenocarcinoma↗
PubMed1991

The biology of beta-adrenergic receptors: analysis in human epidermoid carcinoma A431 cells.

1. G-protein-linked transmembrane signaling has emerged as a major pathway for information transduction across the cell membrane. 2. In addition to photopigments that propagate the signal from light, cell-surface receptors for hormones, neurotransmitters, and autacoids propagate signals from ligand binding to membrane-bound effector units via G-proteins. 3. Biochemical and molecular features of one prominent member of these receptors, the beta-adrenergic receptor, will be highlighted in the present article. 4. The role of the human epidermoid carcinoma A431 cells as a model for the study of the structure and biology of beta-adrenergic receptors will be emphasized. 5. A model for receptor regulation, gleaned from recent advances in the biochemistry, cell and molecular biology of beta-adrenergic receptors, is discussed.

Amino Acid Sequence↗
PubMed1990

[Long-term study of the significance of hormone receptors as prognostic factors in breast cancer].

To check the question as to the prognostic significance of oestrogen and progesterone receptors in invasive breast cancer, the course of the disease was registered in 660 patients in the context of a retrospective study. These patients had been operated on with the objective of curing breast cancer between 1976 and 1984. A receptor analysis of these patients is available with regard to both receptor types. Positive progesterone receptors could be detected in 38%, positive oestrogen receptors in 70%. Values over 15 fmol/mg tissue protein were rated as positive. The proportion of oestrogen-receptor-positive tumours increased with the age of the patients. On the other hand, the progesterone receptor did not show this dependence. During analysis of the median receptor concentrations as well as of the progesterone combinations, a correlation between the axillary lymph node status and the hormone receptor status of the primary tumour could not be observed for the two receptor types. The survival time in relation to the oestrogen receptor status did not indicate any significant effect on survival time. On the other hand, the improvement of survival time depending on the positive progesterone receptor status was highly significant in statistical terms (p less than 0.001) especially in nodal-positive patients. Both patients with axillary lymph node metastases and positive progesterone status, compared with patients without lymph node invasion and a negative progesterone status, had the same survival rate.

Adult↗
PubMed1991

Regulatory functions of a non-ligand-binding thyroid hormone receptor isoform.

Gene regulation by thyroid hormones is mediated through multiple nuclear receptors. Only some of these thyroid hormone receptor (TR) isoforms become transcriptional enhancers in the presence of the thyroid hormone T3. Here we analyze the regulatory function of the human TR alpha 2 isoform. This protein does not bind T3 and is not a transcriptional activator of thyroid hormone-responsive elements (TRE). Transfected TR alpha 2 functions as a constitutive repressor of the transcriptional activators TR alpha 1 and TR beta 1 but also represses heterologous receptors, including the retinoic acid receptor and the estrogen receptor, which can activate TRE-controlled genes. TR alpha 2 protein showed strongly reduced DNA binding to a palindromic TRE when compared with the active TRs. Hybrid receptor analysis revealed that the special properties of the TR alpha 2 protein, including its repressor function and DNA binding characteristics, are intrinsic properties of its carboxyterminus and can be transferred to other receptors. Although it has been shown that the active TRs can act as repressors and silencers due to their strong DNA binding in the absence of hormone, our data show that TR alpha 2 is unlikely to inhibit TRs and other receptors through a competitive DNA binding mechanism. Antibody gel shift experiments suggest that repression by TR alpha 2 might result from interaction with active receptors. Thus, the receptor-like TR alpha 2 isoform differs from typical nuclear receptors in its DNA-binding and ligand-binding properties and appears to regulate the activity of other receptors via protein-protein interaction.

Base Sequence↗
PubMed1992

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↗
PubMed1992

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↗
PubMed1992

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↗
PubMed1992

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↗
PubMed1991

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↗
PubMed1990

[Endometrial cancer and steroid hormone receptors].

Endometrial carcinoma, now the most frequent female genital tract malignancy in Denmark, is generally accepted as an endocrine-related neoplasm. Like normal endometrium, many endometrial carcinomas contain estrogen receptors as well as progesterone receptors. The receptor content appears to correlate with several histopathological features, in particular with tumour differentiation. Well-differentiated lesions are more frequently estrogen and progesterone receptor "positive" than poorly differentiated lesions. Several studies suggest that a high content of estrogen/progesterone receptors in primary endometrial carcinomas, regardless of other prognostic factors, affects the prognosis favourably. Furthermore, receptor status seems to correlate with response of the tumour to progestin therapy. It may be of particular importance, that nearly half of poorly differentiated endometrial carcinomas contain estrogen/progesterone receptors and thus might benefit from progestin therapy. Immunohistochemical receptor analysis directly on cryostat or formalin-fixed tissue sections increases the possibility to explore the histological and biological features, which are determinative for the receptor profile of endometrial carcinomas.

Carcinoma↗
PubMed1978

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↗