Biodistribution of 123I-labeled 4-hydroxytamoxifen derivatives in rats with dimethylbenzanthracene-induced mammary carcinomas

A 123I-labeled tamoxifen derivative with a high affinity for the antiestrogen-binding site (AEBS) has been prepared. Biodistribution studies in rats showed a good linear correlation between the AEBS contents of tissue in fmol/g and the accumulated amount of radioactivity in percent dose per gram at 24 h.

Plasma insulin-like growth factor-I and high affinity growth hormone-binding protein levels increase after two weeks of strenuous physical training

The high affinity growth hormone-binding protein (GHBP) circulates in human blood and represents the extracellular domain of the growth hormone (GH) receptor. It is well known that repetitive bouts of endurance type exercise result in increased integrated GH secretion. As the effects of chronic exercise on plasma GHBP levels have never been studied systematically, we investigated the effect of 2 weeks of intense endurance training on plasma GHBP as well as on plasma insulin-like growth factor (IGF)-I levels in 10 healthy, young, non-obese men. IGF-I was measured as an indicator of the effects of GH release. We also studied 10 control subjects matched for sex, age and activity, who were instructed not to change their customary activities. GHBP was determined by FPLC size exclusion chromatography and subsequent Scatchard plot analysis of the binding data; IGF-I levels were measured by RIA. The results showed that plasma IGF-I and GHBP levels were increased in the subjects who followed the training program. IGF-I and GHBP changed from 252 +/- 56 ng/ml and 912 +/- 59 pmol/l before training, to 344 +/- 61 ng/ml (p < 0.01) and 1020 +/- 48 pmol/l (p < 0.01), respectively. Another effect of the training was that the aerobic capacity of these subjects was better utilized and endurance was improved. In contrast, plasma IGF-I, GHBP, utilization of aerobic capacity and endurance did not change significantly in the control subjects. We conclude that two weeks of strenuous endurance training lead to increased plasma IGF-I and high affinity GHBP levels.

Visceral adipose tissue is associated with circulating high affinity growth hormone-binding protein

Recent data show that body fat distribution, specifically visceral fat accumulation, is associated with the regulation of GH secretion. To our knowledge no studies have been performed with regard to the relationship between plasma high affinity GH-binding protein (GHBP) levels and fat distribution in humans. To address this question, we measured plasma GHBP and insulin-like growth factor I levels as well as visceral, sc abdominal, and hip adipose tissue (AT) areas by using magnetic resonance imaging scanning in 12 patients with GH deficiency (GHD) and in 12 age- and sex-matched healthy subjects. The GHD patients were subsequently treated with GH replacement therapy. Regardless of the GH status of the subjects, body mass index and visceral AT area were positively correlated to plasma GHBP (r = 0.70; P < 0.01 and r = 0.73; P < 0.01, respectively), whereas the sc AT areas at the abdominal level tended to correlate positively with GHBP levels, but did not reach significance (r = 0.44; P = 0.07). The sc AT areas at the hip level were not correlated with plasma GHBP levels. In the GHD patients the pretreatment visceral and abdominal sc AT areas were positively correlated with the change in GHBP levels after GH replacement (r = 0.82; P < 0.01 and r = 0.75; P < 0.01, respectively). The pretreatment sc AT area at the hip level was not associated with the therapy-induced changes in plasma GHBP (r = 0.28; P > 0.10). In summary, this study shows that visceral fat is associated with circulating GHBP levels, suggesting that visceral fat mass may be involved in the regulation of the plasma GHBP level. Further, the amount of abdominal fat in GHD patients may partially determine the plasma GHBP response to GH replacement therapy.

Urinary sex hormone excretions in premenopausal women and coronary heart disease risk: a nested case-referent study in the DOM-cohort

The low incidence of coronary heart disease (CHD) in premenopausal women is partly ascribed to protection by endogenous estrogen production. As a consequence, we hypothesized that premenopausal women with low endogenous estrogen production or high androgen production might be at increased risk for CHD. We studied the relationship between urinary sex hormone excretions and CHD risk by means of a nested case-referent study within a cohort of premenopausal (ages 40-49 yrs) women (n = 11,284). This cohort was formed at a breast cancer screening project in 1982-1986 (The Diagnostisch Onderzoek Mammacarcinoom [DOM] Project). Baseline data included self-administered questionnaires and anthropometric measurements. At the time of screening the women were instructed to collect an overnight urine sample on day 22 of three separate cycles. These urine samples were stored at -20 degrees C. Up to June 1991, 45 subjects were admitted to local hospitals on diagnosis of CHD (29 with myocardial infarction, and 16 with angiographically confirmed coronary disease). Referents were sampled from the cohort, matched for age and year of screening in a 1:3 ratio. In a follow-up study, menopausal state of the subjects was assessed yearly by mailed questionnaires. Urinary excretions of estrone-glucuronide, pregnanediol-glucuronide, and testosterone-glucuronide adjusted by creatinine were similar for cases and referents. Cases had no earlier menopause than referents, although cases had more anovulatory cycles. The occurrence of CHD in middle-aged women is not preceded by a low premenopausal endogenous estrogen production or high androgen production. Anovulatory cycles appear more frequently in women who develop CHD many years later.

Biologically active human islet amyloid polypeptide/amylin in transgenic mice

OBJECTIVE

Human islet amyloid polypeptide (hIAPP), also named amylin, is a pancreatic beta cell protein implicated in the pathogenesis of pancreatic islet amyloid formation and type 2 diabetes mellitus. To study the (patho)physiological roles of hIAPP, we have generated transgenic mice that overexpress hIAPP mRNA, in relation to endogenous mouse IAPP (mIAPP) mRNA, in pancreatic beta cells. The biological activity of human and mouse IAPP derived from pancreatic extracts was determined.

METHODS

Pancreatic and plasma extracts of transgenic and control mice were analyzed by reversed-phase high-performance liquid chromatography (HPLC) and radioimmunoassay, yielding a separation of hIAPP from mIAPP. Biological activity of immunoreactive human and mouse IAPP components derived from pancreatic extracts was assessed by calcitonin receptor-mediated stimulation of cyclic AMP accumulation in T47D human breast carcinoma cells.

RESULTS

The predominant immunoreactive human and mouse IAPP gene products had the retention times on HPLC analysis of the corresponding synthetic peptides. The ratio of bioactive over immunoreactive hIAPP and mIAPP was 0.93 +/- 0.18 and 1.19 +/- 0.56 respectively. In extracts of two plasma pools from 4 transgenic animals, hIAPP was 4.6- to 7-fold more abundant than mIAPP.

CONCLUSION

This study has shown that correctly processed hIAPP produced in transgenic mouse pancreatic beta cells exhibits full biological activity. The results validate these transgenic mice for the study of (patho)physiological roles of hIAPP in vivo.

Progesterone receptors in arachnoid cysts. An immunocytochemical study in 2 cases

We report 2 cases of arachnoid cysts, one with a retrocerebellar and the other with a left temporal localization, in which immunohistochemical studies had been conducted. The results of the immunohistochemistry on the presence of carcino-embryonic antigen (CEA) and glial fibrillary acidic protein (GFAP), and of the scanning- and transmission electron microscopy revealed the cyst lining to be identical to subdural neurothelium. Progesterone receptors were found in the nuclei of cells lining the cyst, which also suggests the similarity of the cyst lining to arachnoid granulations and meningiomas as derivatives of subdural neurothelium, which also possess progesterone receptors.

Specific binding of 11-ketotestosterone in an androgen target organ, the kidney of the male three-spined stickleback,Gasterosteus aculeatus

The kidney of male three-spined stickleback,Gasterosteus aculeatus, hypertrophies during the breeding season and produces a "glue" which is used in the building of the nest. This hypertrophy is androgen dependent, with 11-ketotestosterone (11KT) being more effective than other tested steroids in stimulating this secondary sexual character. In the present study kidneys were excised from stickleback males that had been castrated two days earlier. The purpose of this gonadectomy was to reduce the endogenous levels of androgens without allowing time for the kidney to regress. Tissue fragments were incubated with tritiated 11KT with and without unlabelled steroids at increasing concentrations. Displaceable specific 11KT binding was found in kidney tissue fragments whereas only non-specific binding was observed when liver and muscle were investigated in a similar way. Unlabelled 11KT displaced specifically bound, tritiated 11KT with an ED50-value (50% of displaceable binding) of 28 nM. Similar ED50 values were found for 17\-hydroxy-5α-androstane-3,11-dione (29 nM) and 5α-dihydrotestosterone (20 nM), whereas higher ED50 concentrations were estimated for testosterone (T; 203 nM) and progesterone (69 nM). No displacement of tritiated 11KT was found for the other investigated substances tested; estradiol, 17α,20β-dihydroxy-4-pregnen-3-one, flutamide or cyproterone acetate. No specific binding to kidney tissue fragments could be detected when labelled T was used instead of labelled 11KT. Specific binding of 11KT or T was not found either in the kidney cytosol or nuclear extracts. However, using the kidney membrane fraction a displacement of tritiated 11KT with unlabelled 11KT (10(-6)M) was observed. In conclusion there is a specific binding of 11KT in the stickleback kidney. The absence of binding in liver and muscle, the ED50 value observed and the displacement with some, but not all steroids are consistent with a receptor function. The presence of binding in membrane fractions, but not in cytosol or nuclear extracts suggests that the binding is not related to classic steroid receptors.

Disrupted co-ordination of Pax-8 and thyroid transcription factor-1 gene expression in a dedifferentiated rat thyroid tumour cell line derived from FRTL-5

The mutant rat thyroid cell line FRTL-5/TA, isolated from a non-functional tumour which originated spontaneously from wild-type FRTL-5 cells, shows autonomous TSH-independent growth and loss of the thyroid-specific phenotype, lacking thyroid-specific expression of thyroglobulin (Tg) and thyroid peroxidase (TPO) genes. To investigate the role of the transcription factors Pax-8 and thyroid transcription factor-1 (TTF-1) in rat thyroid tumorigenesis, RNA expression of these two thyroid-specific nuclear factors was measured in FRTL-5/TA tumour cells and compared with the expression in wild-type FRTL-5 cells. TTF-1 gene expression was similar to that in wild-type FRTL-5, and showed a similar down-regulation after stimulation with TSH. The finding suggested normal TTF-1 mRNA and protein expression in both cell lines. By contrast, Pax-8 mRNA transcript signal was markedly reduced in FRTL-5/TA cells, reaching levels as low as 8% of the normal, basal level in FRTL-5 cells. These data indicated that the loss of thyroid-specific expression of Tg and TPO genes in FRTL-5/TA cells was not related to changes in TTF-1 gene expression but rather to reduced Pax-8 gene expression. It was concluded that a disruption of the co-ordinated expression of TTF-1 and Pax-8 is implicated in the loss of thyroid phenotype of FRTL-5/TA cells in terms of reduced Tg and TPO expression.

Radioresistance and p53 status of T2 laryngeal carcinoma. Analysis by immunohistochemistry and denaturing gradient gel electrophoresis

BACKGROUND

Animal experiments and tumor cell line studies have shown that p53 alterations can cause radioresistance. This has not yet been demonstrated in patient groups.

METHODS

We report p53 status in 20 patients with T2 laryngeal carcinoma and recurrent disease after curative therapy. The control group consisted of 16 patients with T2 laryngeal carcinoma without recurrent disease. The p53 gene (exons 5 to 9) was analyzed by Denaturing Gradient Gel Electrophoresis (DGGE). Expression of p53 in biopsy material was visualized by immunohistochemistry (monoclonal antibody BP 53-12-1).

RESULTS

The group with recurrent disease showed a mutation in 9 cases (45%) and overexpression in 14 cases (70%). In 17 cases (85%) either mutation or overexpression was found. The control group showed a mutation in 7 cases (44%) and overexpression in 14 cases (88%). In 14 cases (88%) either mutation or overexpression was found. Adding up both groups a discordance of 50% was found between both detection techniques. The same mutated exon was found in 6 patients (66%) in both primary and recurrent tumors.

CONCLUSIONS

A discordance between immunohistochemistry and DGGE exists in 50% of the cases. Assuming that both p53 mutation and p53 overexpression are indicative of a disturbed p53 checkpoint system, 31 cases (86%) in both groups show an alteration of the p53 system. No significant difference in p53 status in patients with or without recurrent disease exists. Analysis of the p53 status is not of prognostic significance for irradiation as primary treatment.

Dissociation of thyrotropin receptor function and thyrotropin dependency in rat thyroid tumour cell lines derived from FRTL-5

Spontaneously transformed somatic thyrocyte mutants, FRTL-5/TA and FRTL-5/TP, are thyrotropin (TSH) independent for growth and show loss of the thyroid-specific phenotype, with absent thyroglobulin and thyroid peroxidase gene expression. To investigate the role of TSH-receptor (TSH-R) activation in rat thyroid growth and function, binding of TSH and TSH-induced cAMP production were measured in intact cells under identical assay conditions. TSH binding did not differ in terms of affinity and receptor number and presence of 5.6 kb and 3.3 kb mRNA rat TSH-R transcripts was determined in all variants. By contrast, basal cAMP was 11-fold lower in FRTL-5/TA and 6-fold lower in FRTL-5/TP than in wild-type FRTL-5 (1.1 +/- 0.4; P < 0.01). Maximal cAMP production was similar between wild-type and cell variants and stimulation by bovine, rat and recombinant human TSH revealed normal activation patterns. Therefore, a dissociation was present between the loss of TSH control on growth and function, and the presence of a normally functioning TSH-R. Subsequent to TSH incubation FRTL-5/TP and FRTL-5/TA cells showed a different expression pattern of TSH-R and the proto oncogenes c-myc and fos than FRTL-5 wild-type. The data indicated that the cause of the TSH-independency is located down-stream of the cAMP cascade, influencing genes that control the expression of cell cycle-related proto-oncogenes and thyroid-specific genes.

A comparative study of risk factors for hyperplasia and cancer of the endometrium

A cohort study has been carried out to investigate risk factors for cancer as well as hyperplasia of the endometrium. Over the 13 years for which we followed 25,000 women aged 40-65 (who took part in a population-based screening programme for breast cancer), 111 cases of endometrial cancer and 109 cases of endometrial hyperplasia were diagnosed. A comparison of the outcome between the two disease entities revealed that large body weight among postmenopausal women and the use of oestrogenic drugs at all ages were risk factors for both cancer and hyperplasia of the endometrium. However, reproductive histories and premenopausal steroid profiles differed. Steroid excretion determinations in urine samples collected years before diagnosis provided further evidence in favour of the hypothesis of unopposed action of oestrogens in the aetiology of endometrial cancer. In women who were to develop endometrial hyperplasia or cancer the obesity-oestrogen relationship was stronger than in those who remained free of endometrial disease during the period of follow-up. The possible significance of differences in aromatase activity among the obese is considered.

Large discrepancy between prostate-specific antigen results from different assays during longitudinal follow-up of a prostate cancer patient

A case is presented of a patient with stage D prostatic carcinoma, from whom a serum sample proved to be an outlier in a correlation study performed with a 2nd-generation prostate-specific antigen (PSA) assay on the Immulite system (6.4 micrograms/L) and IMx (101 micrograms/L). Clearly, the PSA result reported by Immulite was falsely low. For nine longitudinal samples, Immulite results were approximately 20-fold lower than the IMx value (range of IMx results 5-275 micrograms/L). A selection of the samples was analyzed with the ACS:180, ES-600, and IMx (all &gt; 180 micrograms/L); Immulite, DPC Coat-A-Count IRMA, Immuno 1, AIA-pack, and Tandem-R (all &lt;70 micrograms/L); and Immulite free PSA assay (41 micrograms/L). Gel filtration demonstrated that apart from the alpha1-antichymotrypsin (ACT) complex, no other complexes were found. However, the sample consisted of 53% free PSA (IMx). Possibly, a change of conformation of the PSA molecule resulted in a decreased binding to ACT and a reduced affinity of the antibodies used in the affected assays.

Large discrepancy between prostate-specific antigen results from different assays during longitudinal follow-up of a prostate cancer patient

A case is presented of a patient with stage D prostatic carcinoma, from whom a serum sample proved to be an outlier in a correlation study performed with a 2nd-generation prostate-specific antigen (PSA) assay on the Immulite system (6.4 micrograms/L) and IMx (101 micrograms/L). Clearly, the PSA result reported by Immulite was falsely low. For nine longitudinal samples, Immulite results were approximately 20-fold lower than the IMx value (range of IMx results 5-275 micrograms/L). A selection of the samples was analyzed with the ACS:180, ES-600, and IMx (all > 180 micrograms/L); Immulite, DPC Coat-A-Count IRMA, Immuno 1, AIA-pack, and Tandem-R (all <70 micrograms/L); and Immulite free PSA assay (41 micrograms/L). Gel filtration demonstrated that apart from the alpha1-antichymotrypsin (ACT) complex, no other complexes were found. However, the sample consisted of 53% free PSA (IMx). Possibly, a change of conformation of the PSA molecule resulted in a decreased binding to ACT and a reduced affinity of the antibodies used in the affected assays.

Expression of the gene encoding growth hormone in the human mammary gland

Progestins cause a syndrome of growth hormone (GH) excess and enhanced mammary tumorigenesis in the dog. This has been regarded as being specific for the dog. Recently we reported that progestin-induced GH excess originates from foci of hyperplastic ductular epithelium of the mammary gland in the dog. In the present report we demonstrate by reverse-transcriptase PCR and immunohistochemistry that a main factor involved in tissue growth, i.e. GH, is also expressed in normal and neoplastic human mammary glands. The gene expressed in the human mammary gland proved to be identical to the gene encoding GH in the pituitary gland. The role of progesterone in the GH expression of the human mammary gland needs, however, to be proven. It is hypothesized that this locally produced hGH may play a pathogenetic role in breast cancer.

A patient with a progesterone-producing adrenal adenoma who presented with primary amenorrhea

A case report is presented of a patient with a primary amenorrhea due to a progesterone-producing adrenocortical adenoma. Clinical and endocrinological abnormalities disappeared after removal of the tumor, and the patient experienced her menarche. To our knowledge, a predominantly progesterone-producing adrenal adenoma--in this patient associated with the clinical picture of primary amenorrhea--has not previously been described.

Oestrogen receptor independent expression of progestin receptors in human meningioma--a review

Human meningiomas are rich in progestin receptors (PR), which are expressed in this tissue in an oestrogen independent fashion. In the search for an explanation of this observation, the existence of a protein in human meningioma cytosol which is capable of binding to a synthetic oestrogen responsive element (ERE) has been demonstrated. Using reverse transcriptase, PCR mRNA encoding for the wild-type oestrogen receptor (ER) was found. In addition, several splice variants of ER mRNA have been identified in human meningioma tissue, including variants lacking exons 4, 5 and 7. We found the ER delta 4 protein to have no transcriptional activity and the ER delta 7 protein reportedly is dominant negative. These mutants therefore probably are not responsible for the autonomous PR synthesis in human meningioma. The ER delta 5 protein, by contrast, has been reported to have oestrogen independent transcriptional activity and it is tempting to speculate that this protein is similar or identical to the ERE binding protein we have found in human meningioma. The role of wild type ER mRNA is presently unclear. Activation of other signal transduction pathways in meningioma does not lead to an increased PR concentration. The promoter area of the meningioma PR gene should be investigated for the possible sensitivity to other transcription factors.

Progestin receptors in meningiomas. Comparison of cytosolic assays with immunocytochemical identification in cryostat and paraffin sections

The results are reported of ligand binding and enzyme immunoassays in tumour cytosols, and of immunoperoxidase assays in cryostat and paraffin sections measuring oestrogen (ER) and progestin receptors (PR) in 22 meningiomas and three non-meningioma tumours (two neurinomas and one haemangiopericytoma). With regard to the meningioma tissues, cytochemical immunoperoxidase PR-staining was present in all cryostat sections and in all but one of the paraffin sections. There was a good degree of qualitative accordance between all assay methods; they revealed the picture of "typical" meningioma: high PR and low ER. In this series, immunoperoxidase staining for the detection of PR-receptors, both in cryostat and paraffin sections, rendered encouraging results, thus offering a method for the detection of progestin receptors, which can compete with cytosolic methods.

Functional analysis of an alternatively spliced estrogen receptor lacking exon 4 isolated from MCF-7 breast cancer cells and meningioma tissue

An alternatively spliced mRNA coding for a variant estrogen receptor (ER) missing exon 4 (ERdelta4) was detected in the breast tumor cell line MCF7 and meningioma tissue by using the reversed transcriptase PCR technique. The trans-activational properties of this mutant ER were assessed in embryo carcinoma P19EC and human choriocarcinoma JEG3 cells by co-transfection of the ERdelta4 expression vector with an oxytocin promoter construct containing an estrogen-responsive element. ERdelta4 did not trans-activate the oxytocin promoter in either a hormone-dependent or -independent manner. Co-transfection of ERdelta4 together with the wtER did not show any interference of ERdelta4 on the stimulation of the oxytocin promoter by the wtER. ERdelta4 was translated in vitro. Its capacity to bind estradiol, and the binding of the variant to a synthetic estrogen-responsive element were compared to those of the wild-type receptor. ERdelta4 did not bind to a synthetic estrogen-responsive element, nor did it bind estradiol. Hence, ERdelta4 appears to be a silent variant and we speculate that it is without any role in tumor progression.

An improved method for the determination of islet amyloid polypeptide levels in plasma

We describe an improved method for the determination of islet amyloid polypeptide (IAPP) levels in plasma. Plasma is first extracted with acid-acetone, followed by a specific and sensitive radioimmunoassay (RIA) for IAPP using rabbit-anti-human-IAPP serum. Recovery of synthetic IAPP from plasma was 82 +/- 6% (n = 16). Standard samples, prepared in 'hormone-free' serum, were also extracted with acid-acetone. Displacement curves of serially diluted acid-acetone extracted plasma samples were parallel to the standard curve. The lower detection limit of the RIA was 2.3 +/- 0.1 fmol/sample (n = 5). Intra-assay variations for IAPP concentrations of 4, 17 and 32 pM were 16.3% (n = 10), 9.2% (n = 10) and 6.2% (n = 10); interassay variations were 35.9% (n = 14), 19.9% (n = 15) and 15.4% (n = 15), respectively. Non-stimulated IAPP levels ranged from 2.4 to 12 pM (mean 6 +/- 4 pM, n = 10) in healthy control subjects. IAPP was not detectable in type 1 (insulin-dependent) diabetic patients before and after glucagon administration. In type 2 (non-insulin-dependent) diabetic patients basal levels ranged from 2.2 to 14.5 pM and glucagon-stimulated levels ranged from 2.2 to 38.9 pM. The increase in IAPP varied from 0 to 24.4 pM. The anti-human-IAPP serum had full cross-reactivity with rat IAPP (= mouse IAPP). Transgenic mice overexpressing the human IAPP gene showed elevated plasma IAPP levels as compared to (non-transgenic) control mice. It is concluded that the method presented for the determination of IAPP in plasma is reliable and easy to perform, yielding reproducible results.(ABSTRACT TRUNCATED AT 250 WORDS)

Expression of epidermal growth factor receptor (EGFR) in non-affected and tumorous mammary tissue of female dogs

Epidermal growth factor (EGFR), oestrogen (ER), and progestin (PR) receptor concentrations were determined by radioligand binding assay in non-affected mammary tissues (n = 13) and benign (n = 11) and primary/locally recurrent malignant proliferative mammary lesions (n = 45) and metastases (n = 19) in 65 female dogs. The number of specimens expressing EGFR was not significantly different among these tissues, but EGFR concentration was lower in metastases (P = 0.02) than in benign or primary/locally recurrent malignant lesions not mixed with non-affected mammary tissue. The presence of non-affected mammary tissue in primary cancer specimens was noticed as a factor that may influence results of receptor measurements. No relation was found between the expression of EGFR and that of ER or PR in non-affected or in tumorous mammary tissues. It was concluded that in the dog mammary gland EGFR expression is not associated with conditions of steroid receptor absence of biological agressiveness of neoplastic growth.

Species specificity of triphenylethylene derivatives and of compounds with a steroidal backbone for human and rat liver antioestrogen binding site (AEBS)

The binding affinity of derivatives of the triphenylethylene (TPE) antioestrogen tamoxifen and of steroidal compounds for human liver antioestrogen binding sites (AEBS) was compared with their binding affinity for rat liver AEBS. Despite the observation of some quantitative differences overall a highly significant correlation between the relative binding affinity (RBA) for human and rat liver AEBS was found for all compounds tested (r = 0.93, N = 19, P < 0.001). This was more pronounced for TPE derivatives (r = 0.83, N = 12, P < 0.01) than for cholesterol derived compounds (r = 0.64, N = 7, not significant). We conclude that AEBS from rat liver can be used instead of human livers as a model to study the interactions of antioestrogens with AEBS.

Influence of disease activity on steroid hormone levels in peripheral blood of patients with rheumatoid arthritis

The steroid hormone status of 27 female patients (15 premenopausal and 12 postmenopausal) and 11 male patients with rheumatoid arthritis (RA) was investigated before and after a clinically significant deterioration in disease activity. In postmenopausal patients the serum level of cortisol decreased significantly with the progression of disease activity. No significant change in the serum levels of oestrone, oestradiol, androstenedione, dehydroepiandrosterone, dehydroepiandrosterone sulfate or prolactin was found within the groups. In premenopausal patients serum cortisol levels also decreased, with progression of disease activity, but this difference did not reach statistical significance. In male patients with RA none of the measured steroid hormone levels changed significantly after exacerbation of disease activity. Our data indicate that the synthesis and/or utilization of cortisol might be abnormal in female patients with active rheumatoid arthritis.

Inhibition of the in vivo conversion of androstenedione to estrone by the aromatase inhibitor vorozole in healthy postmenopausal women

Vorozole is a new, potent, and highly selective nonsteroidal aromatase inhibitor, which in animal and human studies was found to be about 1000-fold more potent than aminoglutethimide. Almost all aromatase-inhibiting activity resides in the dextro-enantiomer currently undergoing clinical trials. A marked decrease in circulating estrogens was found in several studies of healthy premenopausal women and male volunteers treated with the racemate, referred to as vorozole racemate. To further evaluate the aromatase-inhibiting potency of this drug, the in vivo conversion of androstenedione to estrone was studied in 12 healthy postmenopausal women. Four h after a single oral dose of vorozole racemate, [14C]androstenedione and [3H]estrone were infused at a constant rate for 2 h. Women were randomized to receive vorozole racemate orally in one of three different doses, i.e., 1, 2.5, and 5 mg, in a double-blind protocol. Each woman acted as her own control in an identical experiment with a placebo carried out 2-4 weeks either before or after the test with vorozole racemate. In the urine, collected for 4 days after each experiment, estrogens were extracted and purified until a constant 3H/14C ratio of estrone was achieved. The percentage conversion of androstenedione to estrone in the 12 placebo experiments was 2.19 +/- 0.60% (mean +/- SD, n = 12). Following a single administration of vorozole racemate, the conversion decreased to 0.14 +/- 0.04%. The percentage inhibition was 93.0 +/- 2.5 (n = 4) following administration of 1 mg vorozole racemate; administration of 2.5 or 5 mg resulted in an inhibition percentage of 93.2 +/- 1.6 or 94.4 +/- 1.2, respectively. It is concluded that a single oral dose of 1-5 mg vorozole racemate results in an almost complete inhibition of in vivo aromatase activity.

Detection of an oestrogen receptor-like protein in human meningiomas by band shift assay using a synthetic oestrogen responsive element (ERE)

When a ligand binding or enzyme immunoassay is used, meningiomas are found to be rich in progestin receptors (PR) whereas oestrogen receptors (ER) are virtually undetectable. A protein that can bind to an oestrogen responsive element (ERE) was detected in meningiomas, by using the band-shift assay. The binding of ER to the ERE is inhibited by the anti-ER monoclonal antibody ER-P31, which is directed to the A/B domain of the ER, indicating that the binding protein is an ER-like protein.