onapristone has been researched along with Leiomyoma* in 2 studies
2 other study(ies) available for onapristone and Leiomyoma
Article | Year |
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Effects of GnRH analogues, 'add-back' steroid therapy, antiestrogen and antiprogestins on leiomyoma and myometrial smooth muscle cell growth and transforming growth factor-beta expression.
The objective of this study was to elucidate the biological significance of GnRH and antiprogestins and antiestrogen in leiomyoma and their interactions with ovarian steroid 'add-back' therapy. Leiomyoma and myometrial smooth muscle cells (LSMC and MSMC) were isolated and exposed to GnRH agonist (leuprolide acetate, LA), 17beta-estradiol (E2), medroxyprogesterone acetate (MPA), GnRH antagonist (Antide), estrogen antagonist, ICI182780 (Fulvestrant) and progesterone antagonists RU486 (Mifepristone) and ZK98299 (Onapristone) and combinations thereof. The rate of DNA synthesis, cell proliferation and transforming growth factor-beta (TGF-beta) expression were then determined. In both cell types, we found that in a dose-dependent manner, LA inhibited, whereas E2, MPA and the combination of E2 + MPA stimulated, the rate of DNA synthesis in these cells. Antide reversed the inhibitory effect of LA, while LA partly inhibited the stimulatory effect of the steroids. In addition, RU486, ICI182780 and ZK98299 at 0.1 micro mol/l or higher doses inhibited the rate of DNA synthesis and partly reversed the effects of E2 and/or MPA. We also found that LSMC expressed elevated levels of TGF-beta1 compared with MSMC. In both cell types, the effects of LA, E2, MPA, RU, ZK and ICI and combinations thereof on TGF-beta1 production were reflective of their effects on DNA synthesis. In line with this, TGF-beta1 was found to stimulate DNA synthesis and the E2-, TGF-beta1- or E2 + TGF-beta1-induced DNA synthesis was found to be inhibited by TGF-beta1 neutralizing antibodies and/or LA. In conclusion, the results provide further evidence that GnRH agonist- and RU486-induced leiomyoma regression is mediated in part through an interactive mechanism that results in altered cell growth and suppression of TGF-beta production. Topics: Estradiol; Estrogen Receptor Modulators; Female; Gonadotropin-Releasing Hormone; Gonanes; Humans; Leiomyoma; Leuprolide; Medroxyprogesterone Acetate; Mifepristone; Muscle Development; Myocytes, Smooth Muscle; Myometrium; Oligopeptides; Progestins; Steroids; Transforming Growth Factors | 2002 |
Onapristone suppresses prolactin production in explant cultures of leiomyoma.
To assess the action of onapristone, a type I antiprogestin, on prolactin (PRL) production by explant cultures of leiomyoma and myometrium.. Explant cultures of myometrium and leiomyomas from 3 premenopausal women undergoing hysterectomy in the proliferative phase of the menstrual cycle.. PRL secretion measured by radioimmunoassay.. PRL secretion was decreased in leiomyomas by onapristone. There was no effect in the myometrium. There was no additional effect with the addition of the type II antiprogestin mifepristone (RU 486).. PRL production is suppressed in leiomyomas but not in myometrium after treatment with onapristone in vitro. This suppression may serve as a marker for the clinical effectiveness of agents used in the treatment of leiomyomas. Topics: Culture Techniques; Dose-Response Relationship, Drug; Female; Gonanes; Hormone Antagonists; Humans; Hysterectomy; Leiomyoma; Myometrium; Premenopause; Progestins; Prolactin; Uterine Neoplasms | 1999 |