Chalbos D, Rochefort H
J Biol Chem. 1984 Jan 25;259(2):1231-8.
R5020, a synthetic progestin, regulates the production of [35S]methionine-labeled proteins released into the medium by T47D human breast cancer cells in culture, as measured by trichloroacetic acid precipitation and dodecyl hydrogen sulfate sodium salt-polyacrylamide gel electrophoresis. Two contrasting responses were observed: (a) a rapid and specific accumulation in the medium of a newly synthesized protein of molecular weight 48,000 and (b) a subsequent general inhibition of the release of proteins within the first 6 days of treatment while the cell number was not altered. These responses were triggered by physiologically active concentrations of progestins (progesterone, R5020, medroxyprogesterone acetate) but not by other classes of steroids, and were not observed in a progesterone receptor negative cell line (BT20), indicating that they were mediated by the progesterone receptor. A progestin antagonist, RU38,486, inhibited the production of the 48-kilodalton released protein. The production of androgen-regulated proteins (43 kilodaltons, 18 kilodaltons) was also increased by dihydrotestosterone and higher concentrations of R5020. These results show that progestins specifically regulate the production of proteins in cell culture. Subsequently, R5020 also inhibit the growth of T47D cells in the presence of estradiol (Vignon, F., Bardon, S., Chalbos, D., and Rochefort, H. (1983) J. Clin. Endocrinol. Metab. 56, 1124-1130), suggesting that the proteins released into the medium may be related to the control of cell proliferation.
R5020是一种合成孕激素，通过三氯乙酸沉淀法和十二烷基硫酸钠-聚丙烯酰胺凝胶电泳法测定，它可调节培养的T47D人乳腺癌细胞释放到培养基中的[35S]甲硫氨酸标记蛋白的产生。观察到两种截然不同的反应：（a）一种分子量为48,000的新合成蛋白在培养基中迅速且特异性地积累；（b）在处理的前6天内，随后对蛋白质的释放产生普遍抑制，而细胞数量未改变。这些反应由生理活性浓度的孕激素（孕酮、R5020、醋酸甲羟孕酮）触发，而非其他类别的类固醇，并且在孕酮受体阴性细胞系（BT20）中未观察到，表明它们是由孕酮受体介导的。一种孕激素拮抗剂RU38,486抑制了48千道尔顿释放蛋白的产生。二氢睾酮和更高浓度的R5020也增加了雄激素调节蛋白（43千道尔顿、18千道尔顿）的产生。这些结果表明，孕激素在细胞培养中特异性地调节蛋白质的产生。随后，R5020在存在雌二醇的情况下也抑制T47D细胞的生长（维尼奥，F.，巴尔东，S.，沙尔博斯，D.，和罗什福尔，H.（1983年）《临床内分泌与代谢杂志》56，1124 - 1130），表明释放到培养基中的蛋白质可能与细胞增殖的控制有关。
