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Immunocytochemical assays for progesterone receptor (PR) using monoclonal antirabbit PR antibodies (PR-ICA) and for estrogen receptor (ER) (ER-ICA) were compared with radioligand binding (dextran-coated charcoal [DCC]) methods for receptor determination in patients with breast cancer. Immunocytochemical staining for PR was exclusively nuclear in localization. In this regard, PR staining is similar to previous findings for ER; PR-ICA showed a sensitivity of 89% and specificity of 100%. ER-ICA was also 89% sensitive and similarly specific. There was good correlation between the degree and intensity of staining and quantitative binding of radioligand. Receptor-positive tumors, however, show considerable variation of immunocytochemical staining, suggesting heterogeneity of cellular PR content. The availability of an immunocytochemical assay for PR increases the discriminatory potential for these methods of receptor determination.

Patients with unstable angina pectoris (UAP; n = 20) and acute myocardial infarction (AMI; n = 34) were studied in the acute phase of ischaemic heart disease. We found significantly higher levels of thrombin-antithrombin-III (TAT) complexes, lower levels of systemic tissue plasminogen activator (t-PA) activity, and higher levels of plasminogen activator inhibitor (PAI) activity in the AMI patients compared to the UAP patients. In contrast to these specific changes, general acute phase reactants such as C-reactive protein, fibrinogen and von Willebrand factor did not differ significantly between the two groups. Studies of the relationship between coagulation (TAT-complexes) and fibrinolysis data revealed a significant positive correlation between plasma antigen concentrations of TAT-complexes and t-PA (P less than 0.02), and between TAT-complexes and PAI-I (P less than 0.002). These observations indicate a common pathophysiological mechanism underlying the changes in coagulation and fibrinolysis, suggesting that coagulation activity and t-PA-related fibrinolysis are interrelated processes in vivo, and probably take place at the level of the endothelial cell.

In a randomized doubled-blind placebo-controlled study, plasma levels of thrombin-antithrombin-III (TAT) and factor VIII activity (VIII:C) were measured pre-operatively and on days 1, 3, 5 and 7 post-operatively in 70 consecutive patients undergoing total hip replacement. Patients received either a subcutaneous injection of low-molecular-weight heparin (LMWH) or placebo once daily. Post-operative deep vein thrombosis (DVT) was diagnosed by bilateral phlebography. The levels of TAT and VIII:C both increased significantly after operation and were not significantly influenced by LMWH. Thirty-three patients in whom post-operative DVT developed had a significantly lower level of VIII:C on day 7, compared with patients without DVT.

c-erbB-2 gene amplification and protein over-expression were investigated in 89 primary tumours and 24 metastases from Norwegian breast cancer patients. Amplification occurred in 22.5% of the primary tumours and 50% of the metastases. The amplification was negatively correlated to the oestrogen receptor (ER) content in both the primary tumours and the metastases. No significant differences between amplified and non-amplified tumours were observed with regard to node status, clinical stage, tumour size or menopausal status, although correlations of borderline significance were found between node status, clinical stage and high degree of gene amplification. All the amplified tumours were of the invasive ductal type. Follow-up data of patients observed for more than 1 year showed a significantly higher recurrence rate in the c-erbB-2 amplified group. Allele loss of chromosome 17p and of 7q was seen in 55% and 48% of the tumours respectively. No significant correlation was found between these losses and clinico-histological parameters. More than 50% of the tumours with a loss of 17q sequences had an amplification of c-erbB-2 which is located on 17q12-21, indicating that only one of the chromosomes may be involved in the amplification of the c-erbB-2. A trend towards a correlation between loss of 17q and high degree of amplification were found. No correlation was found between positive family history of breast cancer and c-erbB-2 gene amplification, nor loss of 17p or 17q sequences. Our data support the hypothesis that amplification correlates with aggressive tumour behaviour, and thus may be used as a prognostic factor in breast carcinomas. The allele losses on 17p and 17q points to tumour suppressor gene or genes on this chromosome, although not as predisposing genes in families.

The urate oxidase (UO) gene of Drosophila melanogaster is expressed during the third-instar larval and adult stages, exclusively within a subset of cells of the Malpighian tubules. The UO gene contains a 69-base-pair intron and encodes mature mRNAs of 1,224, 1,227, and 1,244 nucleotides, depending on the site of 3' endonucleolytic cleavage prior to polyadenylation. A direct repeat, 5'-AAGTGAGAGTGAT-3', is the proposed cis-regulatory element involved in 20-hydroxyecdysone repression of the UO gene. The deduced amino acid sequences of UO of D. melanogaster, rat, mouse, and pig and uricase II of soybean show 32 to 38% identity, with 22% of amino acid residues identical in all species. With use of P-element-mediated germ line transformation, 826 base pairs 5' and approximately 1,200 base pairs 3' of the D. melanogaster UO transcribed region contain all of the cis elements allowing for appropriate temporal regulation and Malpighian tubule-specific expression of the UO gene.

We have studied the effect of glucocorticoids administered in vivo on the activity and synthesis of the cyclooxygenase enzyme (COX) in mice treated with or without concurrent intravenous administration of LPS. Mouse peritoneal macrophages from LPS-treated animals showed a two to three fold increase in COX activity determined by the production of PGE2 and PGI2 after stimulation of the cells with exogenous arachidonate. Dexamethasone injected simultaneously with LPS, 12 h before killing of the animal and removal of the macrophages, completely blocked the LPS-induced increase COX activity in peritoneal macrophages. The regulation observed in COX activity by LPS and dexamethasone are due primarily to changes in COX mass as determined by immunoprecipitation of [35S]methionine endogenously labeled enzyme. In contrast, the COX present in the nonadherent cells and in renal medullary microsomes obtained from the same animals, showed no significant changes between treatments. These results indicate that LPS in vivo stimulates COX synthesis in the peritoneal macrophages but not in the kidney. The effect of dexamethasone to inhibit COX synthesis is selective to the LPS-induced enzyme.

We have previously identified a protein factor, PEBP2 (polyomavirus enhancer-binding protein), in the nuclear extract from mouse NIH 3T3 cells which binds to the sequence motif, PEA2, located within the polyomavirus enhancer A element. Upon cellular transformation with activated oncogene c-Ha-ras, this factor frequently undergoes drastic molecular modifications into an altered form having a considerably reduced molecular size. In this study, the altered form, PEBP3, was purified to near homogeneity. The purified PEBP3 comprised two sets of families of polypeptides, alpha-1 to alpha-4 and beta-1 to beta-2, which were 30 to 35 kilodaltons and 20 to 25 kilodaltons in size, respectively. Both kinds of polypeptides possessed DNA-binding activities with exactly the same sequence specificity. Individual alpha or beta polypeptides complexed with DNA showed faster gel mobilities than did PEBP3. However, the original gel retardation pattern was restored when alpha and beta polypeptides were mixed together in any arbitrary pair. These observation along with the results of UV- and chemical-cross-linking studies led us to conclude that PEBP3 is a heterodimer of alpha and beta subunits, potentially having a divalent DNA-binding activity. Furthermore, PEBP3 was found to bind a second, hitherto-unnoticed site of the polyomavirus enhancer that is located within the B element and coincides with the sequence previously known as the simian virus 40 enhancer core homology. From comparison of this and the original binding sites, the consensus sequence for PEBP3 was defined to be PuACCPuCA. These findings provided new insights into the biological significance of PEBP3 and PEBP2.

Breast cancer specimens from 600 women were assayed for estrogen receptors (ER) using an immunocytochemical assay (ICA) employing the monoclonal antiestrophilin antibody H222 Sp gamma. Results showed significant correlation with biochemical ER determinations as well as with tumor grade and menopausal status. In 449 cases, results of progesterone receptor assay by ICA using the monoclonal anti-PgR antibody KD 68, also correlated significantly with biochemical PgR measurements. The ERICA/PgRICA positivity was significantly more frequent in postmenopausal white women. Colloid carcinomas were most likely to be ERICA positive and PgRICA positive whereas medullary carcinomas were most often negative. In 47 patients with advanced mammary carcinoma, results of ERICA and PgRICA were more closely related to endocrine response than those of ER and PgR by dextran-coated charcoal assay (DCC). In 339 women with Stage I or Stage II breast cancer, ERICA was significantly associated with disease-free survival. Analysis by Cox's proportional hazard model, however, showed PgRICA to be the best predictor of survival and disease-free survival in 197 women at the same stages of disease. These data indicate that ICA is more predictive of prognosis than biochemical ER and PgR. The ease of ICA performance coupled with these results indicate that the method is an acceptable substitute for DCC in analyzing breast cancers for ER/PgR.

The behavior of sex hormone receptors was studied in the cytosol of thyroid tissue samples in order to clarify the effects of sex hormones on diseases of the thyroid. Androgen receptor (AR), estrogen receptor (ER), and progesterone receptor (PgR) were assayed using the dextran-coated charcoal (DCC) method and analyzed by the method of Scatchard. Androgen receptor, ER, and PgR were negative in all of the cytosol prepared from normal thyroid tissues. However, the positive rates for the receptors in the neoplastic and nonneoplastic tissues were 22% for AR, 29% for ER, and 18% for PgR. Especially, the incidence of ER was significantly higher in neoplastic lesions than normal tissues. These data suggest that sex hormones, especially estrogen, may play a role in diseases of the thyroid.

Hemochromatosis is a rare disorder of iron storage. This report illustrates a case of hypogonadotropic-hypogonadism in a female with biopsy-proven hemochromatosis. Dynamic pituitary and gonadal testing revealed subnormal gonadotropin responses to gonadotropin-releasing hormone (GnRH) but normal ovarian reserve, as shown by normal follicular stimulation with hMG. Thus, abnormalities of ovulation and menstruation in patients with hemochromatosis are most likely because of inadequate pituitary responsiveness to GnRH.

To identify changes in haemostatic balance during continuous oestradiol-progestogen treatment, 60 postmenopausal women with climacteric complaints, mean age 55.4 years (range 44-68) were randomly allocated to receive one of four hormone replacement regimens for one year. All four formulations were administered daily and continuously, each contained 2 mg of 17 beta-oestradiol in combination with either norethisterone acetate, 1 mg (group A) or 0.5 mg (group B) or megestrol acetate, 5 mg (group C) or 2.5 mg (group D). No significant changes occurred during treatment within or between the groups in platelet count, fibrinogen and 2-antiplasmin. Activated partial thromboplastin time was shortened (P less than 0.05) in group D and a decline in factor VII activity and antigen (P less than 0.001) and in ATIII activity (P less than 0.05) was noted in group A. Protein C tended to decline in all treatment groups but statistically significant changes were noted only in groups A and C. Two women developed crural thrombosis during the observation period.

Genetic epidemiology studies have indicated that hereditary hemochromatosis (HH) occurs in caucasians with a frequency of 3 to 13 per thousand. Clinical recognition however occurs far less frequently. The disparity is best resolved by defining HH as homozygosity for the HLA-linked hemochromatosis allele, regardless of the total body iron burden. Variability of clinical expression is explained in part by physiologic iron loss in women but variability in males may be due to environmental factors, gene-gene interactions or polymorphisms in mutated hemochromatosis alleles. Although clinical variability is great, the laboratory phenotype of HH is fairly constant and is marked by elevation of the transferrin saturation. The elevated transferrin saturation occurs early in life, before organ iron loading occurs and can be used as a screening tool to detect HH before organ damage occurs. Cloning and characterizing the HH gene, which is located within 1 centimorgan of the HLA-A locus should resolve some of the issues concerning clinical variability.

17 beta-Estradiol is a potent mitogen for hormone-dependent cell lines (MCF-7, T47D and ZR 75.1). However, the degree of hormone sensitivity is very much influenced by culture conditions. In order to understand which factors modulate estrogenic effects on cell growth, four different culture conditions were used: (a) medium with dextran-coated charcoal-treated fetal calf serum (DCC-FCS); (b) medium with dextran-coated charcoal-treated growth factor-inactivated serum (DCC-FCSd); (c) serum-free medium, after a 24-h incubation with serum to allow cell attachment; and (d) serum-free medium on collagen IV-treated plates. In all cell lines the highest cell growth stimulation was achieved when estradiol was added in the presence of 5% DCC-FCS, whereas reducing or removing serum from the culture medium resulted in a decrease in cell proliferation stimulation. We postulate that serum contains some still unknown components able to modulate the degree of estrogenic action in endocrine-dependent breast cancer cell lines.