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  • 1
    Electronic Resource
    Electronic Resource
    Clomiphene-Induced Changes in Endometrial Receptor Kinetics on the Day of Ovum Collection after Ovarian Stimulation: A Study on Cytosol and Nuclear Estrogen and Progestin Receptors and 17/β-Hydroxysteroid Dehydrogenase (1985)
    Oxford, UK : Blackwell Publishing Ltd
    Annals of the New York Academy of Sciences 442 (1985), S. 0 
    Details
    ISSN: 1749-6632
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Natural Sciences in General
    Notes: Clomiphene citrate (CC) in combination with human menopausal gonadotropin (hMG), human chorionic gonadotropin (hCG), or both (hMG-hCG) has a central role in ovarian stimulation in present in vitro fertilization (IVF) programs. It is thought that the ovarian response to clomiphene citrate is dose-dependent, which has led to the use of high doses of this compound.1,2 However, the success rate in embryo transfer (ET) seems to be lower after high-dose than low-dose stimulation.3,4 The reason for this undesirable effect is unknown. Besides having pituitary-ovarian effects, clomiphene citrate, like other antiestrogens, also has endometrial actions. Antiestrogens bind to cytosolic estrogen receptors, and the estrogen-receptor complex formed is transferred to the nucleus for an extended period of time, with resultant changes in female sex steroid receptor kinetics, as has been observed in animal5–7 and human studies.8,9 It is therefore possible that high doses of clomiphene citrate lead to changes in endometrial function that may be detrimental for the success of embryo transfer. We evaluated this possibility by taking endometrial specimens for determination of female sex steroid receptor and 17β-hydroxysteroid dehydrogenase in patients receiving two different doses of clomiphene citrate for ovarian stimulation and in whom adhesions prevented oocyte collection. The results were compared with those obtained in healthy, untreated, ovulatory women.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1749-6632.1985.tb37547.x
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  • 2
    Electronic Resource
    Electronic Resource
    The gene for 17beta-hydroxysteroid dehydrogenase maps to human chromosome 17, bands q12–q21, and shows an RFLP with ScaI (1990)
    Springer
    Human genetics 〈Berlin〉 85 (1990), S. 473-476 
    Details
    ISSN: 1432-1203
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The gene encoding human 17beta-hydroxy-steroid dehydrogenase (17-HSD; EC 1.1.1.62) is assigned to chromosome 17 by Southern blotting analyses of panels of human x rodent somatic cell hybrids and independently to 17q12–q21 using chromosomal in situ hybridization. A search for physical linkage between 17-HSD and the proto-oncogenes, THRA1 and ERBB2 (both reported to be located in this region of chromosome 17) was performed by pulsed-field gel electrophoresis (PFGE) using several rare-cutting restriction endonucleases. Because all three genes hybridized to DNA fragments of different lengths it seems unlikely that the gene for 17-HSD is located very close to THRA1 and ERBB2. Further evidence for this assumption was obtained from the absence of any coamplification of the 17-HSD gene in 9 breast tumors with amplification of the ERBB2 gene. Analyses of Southern blots of ScaI-digested DNAs from unrelated individuals from Northern Finland revealed a relatively infrequent diallelic restriction fragment length polymorphism, the allele frequencies of which were 0.04 (A1) and 0.96 (A2).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00194219
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  • 3
    Electronic Resource
    Electronic Resource
    Human familial and sporadic breast cancer: analysis of the coding regions of the 17β-hydroxysteroid dehydrogenase 2 gene (EDH17B2) using a single-strand conformation polymorphism assay (1994)
    Springer
    Human genetics 〈Berlin〉 93 (1994), S. 319-324 
    Details
    ISSN: 1432-1203
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract 17β-Hydroxysteroid dehydrogenase (17HSD) is one of the key enzymes in estrogen metabolism, catalyzing the reversible reaction between estradiol and the less active estrogen, estrone. The gene encoding this enzyme, EDH17B2, has been mapped to chromosome 17, region q12–q21, in the vicinity of BRCA1, an as yet unidentified gene that appears to be involved in familial breast cancer and in familial ovarian cancer. The possibility that EDH17B2 gene is the same as BRCA1 was tested by screening for mutations in the coding regions of EDH17B2, using a polymerase chain reaction/single-strand conformation polymorphism method. An A→G transition creating a new BstUI site at exon 6 was the only frequent sequence alteration found in the coding region of the gene. This mutation also led to an amino acid substitution of serine to glycine at position 312 (312S→312G) in the 17HSD protein. Since the nucleotide change was detected both in specimens from patients with familial or sporadic cancer and in control samples, and at similar rates, this mutation appears to be of a polymorphic nature. In addition, a rare polymorphism located at intron 5 was detected. This C→T substitution creates a BbvI site and is not thought to have any effect on 17HSD activity. The results indicate that there are no major alterations in the coding areas of EDH17B2 and thus studies testing the hypothesis that EDH17B2 may be the same as BRCA1 should be extended to the promoter and regulatory elements of EDH17B2.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00212030
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  • 4
    Electronic Resource
    Electronic Resource
    Radiolabelling of monoclonal antibodies: Optimization of conjugation of DTPA to F(ab′) 2-fragments and a novel measurement of the degree of conjugation using Eu(III)-labelling (1989)
    Springer
    European journal of nuclear medicine 15 (1989), S. 157-161 
    Details
    ISSN: 1619-7089
    Keywords: Radioimaging ; Prostatic acid phosphatase ; Immunoreactivity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract F(ab′) 2 fragments (at concentrations of 5–30 mg/ml) derived from monoclonal antibodies raised against human prostate specific acid phosphatase were derivatized with a bicyclic anhydride of diethylenetriaminepentaacetic acid (cDTPAA) in the molar ratios of cDTPAA/F(ab′) 2 of 1:1, 5:1, 10:1 or 50:1. The most optimal product, aimed at radioimaging of prostatic cancer was obtained when the antibody fragment concentration was at least 10 mg/ml and the molar ratio of cDTPAA to F(ab′) 2 was 5:1 cDTPAA was added dissolved in dimethylsulfoxide (DMSO). Under these conditions, 1.8–2.2 DTPA molecules/F(ab′) 2 molecule were bound, giving a coupling efficiency of 37%–44%, and the labelling efficiency with 111In (3 mCi/1 mg protein) was 95%±3% (n=7). The antibody fragment completely retained its immunoreactivity measured by radioimmunoassay and showed no aggregation when studied using sodium dodecyl sulfatepolyacrylamide gel electrophoresis (SDS-PAGE). For evaluation of the degree of conjugation of DTPA to the antibody fragment, a novel technique was developed relying on the use of EuCl3, and the measurement of europium fluorescence employing time resolved fluorometry. Results by EuCl3 labelling were identical to those obtained by the conventional 111InCl3 labelling method.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00254630
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  • 5
    Electronic Resource
    Electronic Resource
    Biodistribution in normal mice of an111in-labelled prostatic acid phosphatase-specific antibody and its F(ab′)2 fragments derivatized site-specifically or via bicyclic diethyl enetriaminepentaacetic acid anhydride (1990)
    Springer
    European journal of nuclear medicine 16 (1990), S. 621-626 
    Details
    ISSN: 1619-7089
    Keywords: Radioimaging ; Radiotherapy ; Conjugation of antibodies
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract In this study we examined optimization of derivatization of monoclonal antibodies and their fragments intended for use as radiopharmaceutical in radioimaging and/or radioimmunotherapy of prostatic cancer. Two different principles were used to conjugate diethylene triaminepentaacetic acid (DTPA) to a monoclonal antibody (Mab, subclass IgG1) raised against human prostatic acid phosphatase (PAP). In addition, the F(ab′)2 fragments of this Mab were also derivatized. We used the cyclic anhydride of DTPA (CA-DTPA) as a chelating agent for these two protein moieties. Furthermore, the Mab and the F(ab′)2 fragments were modified site-specifically by attaching linkers,N-(p-aminobenzyl)diethylenetriaminetetraacetic acid (p-NH2-Bz-DTTA) and 1(p-aminobenzyl)diethylenetriaminepentaacetic acid (p-NH2-Bz-DTPA), to the carbohydrate components of the parent molecules. In this study, biodistribution of the111In-labelled derivatives was investigated in normal mice. All the derivatives of IgG1 demonstrated a slower blood clearance than the corresponding derivatives of the F(ab′)2 fragments. This property was particularly pronounced in the site-specifically conjugated derivatives of IgG1. All the derivatives studied accumulated in the liver, kidney, and spleen. The CA-DTPA derivatives of F(ab′)2 fragments showed the highest kidney-to-blood ratios of radioactivity compared with the other compounds studied. The derivatives of IgG1 showed a higher percentage of the injected dose in liver and spleen tissues than the derivatives of the F(ab′)2 fragments. The F(ab′)2 fragments studied also gave rise to site-specific derivatives, which demonstrated that carbohydrates were also present in this part of the molecule. They behaved similarly to the CA-DTPA F(ab′)2 derivative in other respects, but the kidney accumulation was lower at 72 and 120 h. The F(ab′)2 fragments studied would be better suited for radioimaging than the derivatives of the IgG1 studied due to the rapid blood clearance of the F(ab′)2 derivatives. In contrast, the derivatives of IgG1, especially thep-NH2-Bz-DTPA conjugate, which showed the lowest kidney uptake, might be more suitable candidates for the development of therapeutic agents.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00998159
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  • 6
    Electronic Resource
    Electronic Resource
    Reply (1991)
    Springer
    European journal of nuclear medicine 18 (1991), S. 997-998 
    Details
    ISSN: 1619-7089
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00180425
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  • 7
    Electronic Resource
    Electronic Resource
    Effects of tumour mass and circulating antigen on the biodistribution of111In-labelled F(ab′)2 fragments of human prostatic acid phosphatase monoclonal antibody in nude mice bearing PC-82 human prostatic tumour xenografts (1991)
    Springer
    European journal of nuclear medicine 18 (1991), S. 339-345 
    Details
    ISSN: 1619-7089
    Keywords: Radioimaging ; Radiotherapy ; Prostatic cancer
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We have evaluated the effects of tumour mass and circulating antigen (prostatic acid phosphatase, PAP) on the biodistribution and the incorporation of111In-labelled F(ab′)2 monoclonal antibody (MoAb) fragments directed against human PAP into human prostatic tumours (PC-82; 0.1–8.9 g) growing in nude mice. The radioactivities in the blood, liver, spleen, kidney and tumour were compared at 1, 3, 4 and 6 days after the intravenous administration of the antibody fragments. There was a significant correlation between the tumour size and the serum PAP concentration in the model employed. Even tissue of a small tumour (〈 0.1 g) had a high concentration of PAP, but it was not secreted into the circulation in detectable amounts when measured by radioimmunoassay (the lowest standard was 0.5 μg/l). The percentage uptake by tumours of the injected dose per gram of tissue (%ID/g) was inversely proportional to the tumour size at 24 h after the administration of111In-labelled F(ab′)2 fragments. This relationship had levelled off by 72 h and most likely reflected a better vascularisation of the smaller tumours. Our results show that the increase in tumour size and in the concentration of circulating antigen in the blood led to decreased tumour-to-blood ratios, since there was a tendency for higher blood activities in mice with larger tumours and higher serum PAP concentrations. There was no correlation between tumour size and label uptake by the liver during the follow-up over 144 h, although serum PAP concentrations ranged from 3.1 μg/l to 352 μg/l. On the other hand, when compared with our previous data obtained with non-tumour-bearing mice, there was a significant increase in the uptake by the liver and spleen. These results indicate that even a small concentration of circulating antigen was able to trigger an abnormal change in the biodistribution of MoAbs.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02285462
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  • 8
    Electronic Resource
    Electronic Resource
    17β‐hydroxysteroid dehydrogenases in normal human mammary epithelial cells and breast tissue (1999)
    Springer
    Breast cancer research and treatment 57 (1999), S. 175-182 
    Details
    ISSN: 1573-7217
    Keywords: breast cells ; estrogens ; hydroxysteroid dehydrogenases
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract 17β‐hydroxysteroid dehydrogenase activity represents a group of several isoenzymes (17HSDs) that catalyze the interconversion between highly active 17β‐hydroxy‐ and low activity 17‐ketosteroids and thereby regulate the biological activity of sex steroids. The present study was carried out to characterize the expression of 17HSD isoenzymes in human mammary epithelial cells and breast tissue. In normal breast tissues 17HSD types 1 and 2 mRNAs were both evenly expressed in glandular epithelium. In two human mammary epithelial cell lines, mRNAs for 17HSD types 1, 2 and 4 were detected. In enzyme activity measurements only oxidative 17HSD activity, corresponding to either type 2 or type 4 enzyme, was present. The role of 17HSD type 4 in estrogen metabolism was further investigated, using several cell lines originating from various tissues. No correlation between the presence of 17HSD type 4 mRNA and 17HSD activity in different cultured cell lines was detected. Instead, oxidative 17HSD activity appeared in cell lines where 17HSD type 2 was expressed and reductive 17HSD activity was present in cells expressing 17HSD type 1. These data strongly suggest that in mammary epithelial cell lines the oxidative activity is due to type 2 17HSD and that oxidation of 17β‐hydroxysteroids is not the primary activity of the 17HSD type 4 enzyme.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006217400137
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