An Italian Committee for the quality assessment of steroid receptor assay was instituted in 1979; the number of laboratories participating in this program increased from 7 in 1979 to 43 in 1989. The Italian program in collaboration with EORTC (European Organization Research and Treatment of Cancer) initiatives, utilizes as working standards lyophilized samples that tolerate prolonged storage at 4 degrees C. The national representatives agreed, according to EORTC, that all laboratories would perform, for measurement of steroid receptors, the dextran coated charcoal (DCC) method using the same concentration of radioactive ligands (3-H-estradiol, 3-H-ORG-2058) and would determine the non-specific binding with the same compounds (diethylstilbestrol and ORG-2058). The computation method is a potential source of interlaboratory variation; the multipoint Scatchard analysis, though difficult to apply for receptor problems, is the most widely used approach at present. The standardized DCC method is the most common and recognized (Food and Drug Administration) procedure for quantifying hormone receptor in human cancer. Since new technologies are being introduced (receptor enzyme immunoassay, EIA), adequate programs of quality assessment are required; in general, it has demonstrated an excellent correlation between radioligand binding assay (DCC) and immunochemical assay (EIA). Other prognostic factors, such as proteins produced by oncogenes and growth factors of the malignant cells have become more important. Some of these factors, as well as estrogen receptor status, seem the major determinants of recurrence after the first treatment.

1986-02-01·Journal of Steroid Biochemistry

Evidence that a non-aromatizable metabolite of norethisterone induces estrogen-dependent pituitary progestin receptors

Article

作者: Ana E. Pèrez ; Gregorio Pérez-Palacios ; Gustavo A. García ; Bertha Ch́avez ; Arturo Angeles ; Felipe Vilchis

Neutral reduced metabolites of norethisterone (NET) specifically interact with intracellular estrogen receptors in target organs. To determine if this interaction can effectively initiate estrogen-dependent cellular responses, the effects of an A-ring-reduced NET derivative upon the induction of cytosol-located pituitary progestin receptors (PR) and uterine growth were studied in adult castrated female rats. Different doses of 17 alpha-ethynyl-5 alpha-estran-3 beta, 17 beta-diol (3 beta, 5 alpha-NET) were s.c. administered to ovariectomized animals for 6 days. 17 beta-Estradiol (E2) and oil-treated rats served as experimental controls. Pituitary PR were labeled in vitro by a post-gradient technique using [3H]ORG-2058 as the ligand. PR binding specificity was determined by the use of an excess of radioinert steroids. The results demonstrated that administration of 3 beta, 5 alpha-NET induced specific 8-9S pituitary cytosol PR in a dose-dependent manner. Binding properties of the 3 beta, 5 alpha-NET-induced progestin binding sites (Kd = 1.0 X 10(-9) M; NBS = 1.2 X 10(-9) M) appear indistinguishable from those induced by E2. In addition, 3 beta, 5 alpha-NET administration resulted in a significant increase in uterine weight at the expense of myometrium and endometrium growth in a similar fashion to that observed in the E2-treated group. When 3 alpha, 5 alpha-epimeric alcohol (3 alpha, 5 alpha-NET) was administered, induction of pituitary PR and uterine growth were also observed although to a lesser extent. Inasmuch as the results demonstrate that neutral non-aromatizable NET metabolites induce biochemical and morphological estrogenic responses, they offer an alternative explanation for the mechanism of estrogen-like action of this synthetic contraceptive progestin.

100 项与盐酸丁丙诺啡/格拉司琼相关的药物交易

登录后查看更多信息

研发状态

10 条进展最快的记录,

后查看更多信息

适应症	最高研发状态	国家/地区	公司	日期
术后疼痛	临床1期	-	Braeburn, Inc.	-
术后疼痛	临床1期	瑞典	Camurus AB	-
术后恶心呕吐	临床1期	-	Braeburn, Inc.	-
术后恶心呕吐	临床1期	瑞典	Camurus AB	-