title: Effect of the antiprogesterone RU-38486 on meningioma implanted into nude mice.
abstract: Meningiomas have been shown to have steroid-binding proteins. In vitro, estradiol, progesterone, and the antiestrogen tamoxifen stimulate tumor growth. However, incubation of tumor cells with an antiprogesterone agent results in tumor inhibition. In this investigation, a human meningioma was implanted subcutaneously in athymic nude mice. Two treatment groups were established, one receiving the antiprogesterone agent RU-38486 (10 mg/kg/day in suspension) and the other receiving only vehicle. After 3 months, the tumor growth index (defined as the tumor volume at 3 months divided by the initial tumor volume) was 0.25 +/- 0.46 (mean +/- standard deviation) in the group receiving antiprogesterone and was 1.54 +/- 0.58 in the control group (p = 0.041). Further investigation of the effect of antiprogestational agents on the growth and hormone-binding proteins of other meningiomas will better define the mechanism of their effects.
mesh_terms: D000818:Animals; D004963:Estrenes / Q000627:therapeutic use*; D006801:Humans; D008577:Meningeal Neoplasms / Q000188:drug therapy*; D008579:Meningioma / Q000188:drug therapy*; D051379:Mice; D008819:Mice, Nude; D015735:Mifepristone; D009368:Neoplasm Transplantation; D011374:Progesterone / Q000037:antagonists & inhibitors*; D013997:Time Factors
chemical_list: D004963:Estrenes; D015735:Mifepristone; D011374:Progesterone