Validation of in vitro screening models for progestagenic activities: inter-assay comparison and correlation with in vivo activity in rabbits.

The PR CALUX® cell line is a stably transfected human U2-OS cell line expressing the human PR and a luciferase reporter construct containing three progesterone-responsive elements coupled to a minimal promoter. The validity of this assay has been studied as an alternative to the McPhail assay in rabbits, an in vivo assay to detect progestins. The PR CALUX assay was characterized by its stable expression of PR protein which leads to induction of endogenous PR target genes by progestins. It was found to have a highly selective response to low levels of different progestins, as well as an insignificant response to other nuclear hormone receptor ligands. As an important step in their validation, the PR CALUX bioassay was compared with another earlier described in vitro bioassay, a Chinese Hamster Ovary (CHO) cell-based PR-CHO reporter gene assay as well as with an in vitro PR-binding (PR-BIN) assay, and the in vivo McPhail assay. This was done using 35 (with the most accurate potency determinations in all tests) and 50 (with less reliable potency determinations in some tests) compounds tested in all assays. The correlation scores between PR CALUX and PR-CHO were r(2)=0.77, and 0.93, respectively; between PR CALUX and PR-BIN r(2)=0.69 and 0.80. Comparison between either the PR CALUX or the PR-CHO transactivation assay and the in vivo McPhail assay revealed very good correlations of r(2)=0.68 (n=35), and 0.85 (n=50). The transactivation assays can discriminate very potent, from potent, weak and inactive compounds rather easily. Besides testing the biological activity of pure chemicals and pharmaceuticals in vitro, the PR CALUX and PR-CHO transactivation assays proved to be relatively good predictors of in vivo progestagenic activity, allowing the use of these assays as prescreening methods or in vitro alternatives.

[1]  David Thompson,et al.  Compound Profiling Using a Panel of Steroid Hormone Receptor Cell-Based Assays , 2008, Journal of biomolecular screening.

[2]  Sujata Halder,et al.  Detection of potential (anti)progestagenic endocrine disruptors using a recombinant human progesterone receptor binding and transactivation assay , 2008, Molecular and Cellular Endocrinology.

[3]  A D Vethaak,et al.  Development of a stably transfected estrogen receptor-mediated luciferase reporter gene assay in the human T47D breast cancer cell line. , 1999, Toxicological sciences : an official journal of the Society of Toxicology.

[4]  Timo Hamers,et al.  In vitro profiling of the endocrine-disrupting potency of brominated flame retardants. , 2006, Toxicological sciences : an official journal of the Society of Toxicology.

[5]  G. Vollmer,et al.  Detection of anabolic steroid abuse using a yeast transactivation system , 2008, Steroids.

[6]  M. Breslin,et al.  The novel progesterone receptor antagonists RTI 3021-012 and RTI 3021-022 exhibit complex glucocorticoid receptor antagonist activities: implications for the development of dissociated antiprogestins. , 1999, Endocrinology.

[7]  E. M. de Groene,et al.  Development of an androgen reporter gene assay (AR-LUX) utilizing a human cell line with an endogenously regulated androgen receptor. , 2001, Analytical biochemistry.

[8]  K. Umesono,et al.  The nuclear receptor superfamily: The second decade , 1995, Cell.

[9]  R. Winneker,et al.  Novel 6-aryl-1,4-dihydrobenzo[d]oxazine-2-thiones as potent, selective, and orally active nonsteroidal progesterone receptor agonists. , 2003, Bioorganic & medicinal chemistry letters.

[10]  P. Roy,et al.  Screening of some anti-progestin endocrine disruptors using a recombinant yeast based in vitro bioassay. , 2008, Toxicology in vitro : an international journal published in association with BIBRA.

[11]  W. Fenical,et al.  Nonsteroidal human progesterone receptor modulators from the marine alga Cymopolia barbata. , 1995, Molecular pharmacology.

[12]  C. Lyttle,et al.  Quantitative analysis of gene regulation by seven clinically relevant progestins suggests a highly similar mechanism of action through progesterone receptors in T47D breast cancer cells , 2005, The Journal of Steroid Biochemistry and Molecular Biology.

[13]  R. Dijkema,et al.  Human progesterone receptor A and B isoforms in CHO cells. II. Comparison of binding, transactivation and ed50 values of several synthetic (anti)progestagens in vitro in CHO and MCF-7 cells and in vivo in rabbits and rats , 1998, The Journal of Steroid Biochemistry and Molecular Biology.

[14]  J. Graham,et al.  Physiological action of progesterone in target tissues. , 1997, Endocrine reviews.

[15]  M. Mcphail The assay of progestin , 1934, The Journal of physiology.

[16]  C. Lyttle,et al.  Molecular and Pharmacological Properties of a Potent and Selective Novel Nonsteroidal Progesterone Receptor Agonist Tanaproget* , 2005, Journal of Biological Chemistry.

[17]  W. Schoonen,et al.  High-throughput screening for analysis of in vitro toxicity. , 2009, EXS.

[18]  J. Martial,et al.  Use of reporter cell lines for detection of endocrine-disrupter activity , 2004, Analytical and bioanalytical chemistry.

[19]  R. García-Becerra,et al.  Transactivation of progestin- and estrogen-responsive promoters by 19-nor progestins in african green monkey kidney CV1 cells , 2001, Endocrine.

[20]  Abraham Brouwer,et al.  Glucocorticoid-enhanced expression of dioxin target genes through regulation of the rat aryl hydrocarbon receptor. , 2007, Toxicological sciences : an official journal of the Society of Toxicology.

[21]  B. O’Malley,et al.  Inhibition of the 26S proteasome blocks progesterone receptor-dependent transcription through failed recruitment of RNA polymerase II , 2005, The Journal of Steroid Biochemistry and Molecular Biology.

[22]  F. Stanczyk All progestins are not created equal , 2003, Steroids.

[23]  Saskia S Sterk,et al.  Detection of anabolic androgenic steroid abuse in doping control using mammalian reporter gene bioassays. , 2009, Analytica chimica acta.

[24]  E. Milgrom,et al.  Mechanisms of nuclear localization of the progesterone receptor: Evidence for interaction between monomers , 1989, Cell.

[25]  H. Hamersma,et al.  Contraceptive progestins. Various 11-substituents combined with four 17-substituents: 17α-ethynyl, five- and six-membered spiromethylene ethers or six-membered spiromethylene lactones , 2000, The Journal of Steroid Biochemistry and Molecular Biology.

[26]  K. Chwalisz,et al.  Progesterone receptor modulators and progesterone antagonists in women’s health , 2000, Steroids.

[27]  Bart van der Burg,et al.  Interaction of polycyclic musks and UV filters with the estrogen receptor (ER), androgen receptor (AR), and progesterone receptor (PR) in reporter gene bioassays. , 2004, Toxicological sciences : an official journal of the Society of Toxicology.

[28]  Y. Kurata,et al.  In vitro and in vivo characterization of novel nonsteroidal progesterone receptor antagonists derived from the fungal metabolite PF1092C , 2002, The Journal of Steroid Biochemistry and Molecular Biology.

[29]  David J. Handelsman,et al.  Tetrahydrogestrinone is a potent androgen and progestin. , 2004, The Journal of clinical endocrinology and metabolism.

[30]  R. Dijkema,et al.  Human progesterone receptor A and B isoforms in CHO cells. I. Stable transfection of receptor and receptor-responsive reporter genes: transcription modulation by (anti)progestagens , 1998, The Journal of Steroid Biochemistry and Molecular Biology.

[31]  Willem G Schoonen,et al.  Comparison of in vitro and in vivo screening models for androgenic and estrogenic activities. , 2006, Toxicological sciences : an official journal of the Society of Toxicology.

[32]  Thomas D. Schmittgen,et al.  Analysis of relative gene expression data using real-time quantitative PCR and the 2(-Delta Delta C(T)) Method. , 2001, Methods.

[33]  Bart Van der Burg,et al.  Detection of multiple hormonal activities in wastewater effluents and surface water, using a panel of steroid receptor CALUX bioassays. , 2008, Environmental science & technology.

[34]  Abraham Brouwer,et al.  Development of androgen- and estrogen-responsive bioassays, members of a panel of human cell line-based highly selective steroid-responsive bioassays. , 2004, Toxicological sciences : an official journal of the Society of Toxicology.

[35]  B. van der Burg,et al.  Human retinoic acid (RA) 4-hydroxylase (CYP26) is highly specific for all-trans-RA and can be induced through RA receptors in human breast and colon carcinoma cells. , 1998, Cell growth & differentiation : the molecular biology journal of the American Association for Cancer Research.

[36]  W. Schoonen,et al.  Development of a high-throughput in vitro bioassay to assess potencies of progestagenic compounds using chinese hamster ovary cells stably transfected with the human progesterone receptor and a luciferase reporter system. , 1998, Analytical biochemistry.

[37]  F. Orio,et al.  A stable prostatic bioluminescent cell line to investigate androgen and antiandrogen effects , 2000, Molecular and Cellular Endocrinology.

[38]  D. New,et al.  Reporter gene assays and their applications to bioassays of natural products , 2003, Phytotherapy research : PTR.

[39]  J. Y. Roberge,et al.  Characterization of a new class of selective nonsteroidal progesterone receptor agonists , 2004, Steroids.