Oestrogens assays

Bullock, D.G. and Wilde, C.E. (1985) External quality assessment of urinary pregnancy oestrogen assay further experience in the UK, Ann. Clin. Biochem. 22, 273. 

Vanderperren, E. Demare, W. Blust, R. Cooreman, K. Bossier, P. Oestrogenic activity of CPRG (chlorophenol red- 3-D-galactopyranoside), a 3-galactosidase substrate commonly used in recombinant yeast oestrogenic assays. Biomarkers 2001, 6, 375-380. 

It is not certain that all the effects of DES can be ascribed to its oestrogenic activity (that is to say, directly related to its ability to bind to the oestrogen receptor), but it would appear from experience with this compound that rodent assays are able to detect the relevant toxicological effects. What then was the... 

Oestrogen receptor binding/Reporter gene assay. 

Dodds, E.C. (1937a). The chemistry of oestrogenic compounds and methods of assay. British Medical Journal 1937, 398-399. 

NAGEL s c, VOM SAAL F s, WELSHONS w V (1999) Developmental effects of oestrogenic chemicals are predicted by an in vitro assay incorporating modification of cell uptake by serum. J Steroid Biochem Mol Biol. 69 343-57. 

Besides these toxic effects, many studies showed the potential for oestrogenic activity of several sunscreen agents. These effects can be detected in vivo or at in vitro assays. The last are usually more sensitive than the former, concluding sometimes in an overestimation of the effects. Nevertheless, in vitro assays are faster and cheaper and allow a rapid screening of oestrogenic compounds. Therefore, a combination of different assays is recommended in order to have a wide spectrum of toxicity data that would allow performing a reliable risk assessment. 

Meegan et al. reported the synthesis of a number of [3-lactams and these were evaluated in a series of in vitro assays, which determined their antiproliferative activity in MCF-7 and MDA-MB-231 breast cancer cell lines and also their affinity for the oestrogen receptor (Fig. 6). The cytotoxicity of the [3-lactams was determined in the LDH assay to establish that the antiproliferative effects observed were due to cytostasis rather than cellular necrosis. Most of the compounds demons-treated low cytotoxicity, indicating that their action is cytostatic rather than cytotoxic. Cytotoxicity values considerably below that obtained for tamoxifen (13.4%, 10 pM) were observed with a most potent compound (3%, 10 pM in MCF-7 cell... 

Huang, A., Pettigrew, N. M., and Watson, P. H. 1996. Immunohistochemical assay for oestrogen receptors in paraffin wax sections of breast carcinoma using a new monoclonal antibody. J. Pathol. 180.223-221. 

There are many techniques that can be employed to assess the immuno-genicity of a vaccine candidate, and laboratories interested in pursuing this objective should also explore other assays suited to their purposes. In this model, vaccine immunogenicity is measured by determining levels of anti-LHRH antibodies induced in mice immunized with lipopeptide or a nonlipi-dated peptide control. It is important to correlate vaccine immunogenicity with biological function, and we measure the reproductively capability of vaccinated female mice as an indication of vaccine efficacy. Techniques that determine testosterone and oestrogen levels are also useful. 

Steroid hormones achieve their effects on target tissues through intracellular receptor proteins. According to recent views, oestrogen and progestin receptors are localized in the nuclear compartment of the cells, whereas glucocorticoid receptors may reside in both the cytoplasm and the nucleus. Determination of the intracellular localization of androgen receptors awaits the development of (monoclonal) antibodies which will enable immunohistochemical studies. The molecular aspects of the mechanism of action of steroid hormones will be covered in other chapters [1-3] in this volume. The present chapter deals with the characterization, assay and purification of steroid receptors. 

Jarman M, Leung OT, Leclercq G, Devleeschouwer N, Stoessel S, Coombes RC, Skilton RA (1986) Analogues of tamoxifen the role of the basic side-chain. Applications of a whole-cell oestrogen-receptor binding assay to N-oxides and quaternary salts. Anticancer Dmg Des 1 259-268... 

Hepatotoxicity—enzyme release and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazodium bromide (MTT) assay on fresh or cryopreserved (human) hepatocytes Endocrine disruption—yeast and mammalian reporter gene assay (oestrogenicity and adrogenicity)... 

Pedersen KL, Pedersen SN, Christiansen LB, et al. The preservatives ethyl-, propyl-, and butylparaben are oestrogenic in an in vivo fish assay. Pharmacol Toxicol 2000 86(3) 110-113. 

Studies investigating hormonal activity revealed the oestrogenic activity of short-chain NPE in a number of test systems using either recombinant yeast, oestrogen-sensitive MCF-7 cells [98] or a rodent uterotrophic assay response. None of these assays have yet been validated as an internationally accepted toxicity test method, although the MCF-7 and uterotrophic assays have been established for a number of years as standard assays for oestrogenic activity. 

B6. Beling, C. G., Gel filtration of conjugated urinary oestrogens and its application in clinical assays. Acta Endocrinol. Suppl. 79 (1963). 

H6. Hawkins, R. A., Sangster, K., Tesdale, A., Levack, P. A., Anderson, E. D. C., Chetty, U., and Forrest, A. P. M., The cytochemical detection of oestrogen receptors in fine needle aspirates of breast cancer correlation with biochemical assay and predication of response to endocrine therapy. Br. J. Cancer 58, 77-80 (1988). 

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