Selective Progesterone Receptor Modulator Asoprisnil Research Articles

A 12-month extension study to evaluate the safety and efficacy of asoprisnil in women with heavy menstrual bleeding and uterine fibroids.

A 12-month extension study to evaluate the safety and efficacy of asoprisnil in women with heavy menstrual bleeding and uterine fibroids.

Effect of asoprisnil on uterine proliferation markers and endometrial expression of the tumour suppressor gene, PTEN

The selective progesterone receptor modulator asoprisnil suppresses uterine bleeding and decreases leiomyoma volume while maintaining follicular phase estrogen concentrations. For safety of potential clinical applications, any proliferative effect of asoprisnil on uterine tissues, particularly endometrium, needs to be established. In a double-blind, randomized, placebo-controlled study (continuation of previously published trial No. NCT00150644 (Williams et al., 2007 and Wilkens et al., 2008)), 33 patients with symptomatic uterine leiomyomata received placebo, 10 or 25 mg asoprisnil daily for 12 weeks before hysterectomy. Proliferation markers Ki-67 and anti-phospho-histone H3 (PH3) were immunolocalized in endometrium, myometrium and leiomyoma tissue. Endometrial PTEN (phosphatase and tensin homologue, a tumour suppressor gene) expression was also assessed by immunohistochemistry. PH3-positive glandular and stromal cells were counted per measured endometrial area. Endometrial Ki-67 expression was assessed using stereological methods. Stained myometrial and leiomyoma cells were counted per 10 fields (x250). PTEN immunostaining was quantified using a histoscore. Each asoprisnil group was compared with placebo (secretory phase) with significance at 0.05 level. Endometrial epithelial proliferation and PTEN expression were not significantly different between placebo and asoprisnil groups. Decreased stromal Ki-67 expression (P < 0.05) suggested any effect of asoprisnil on endometrial proliferation to be inhibitory. Immunolocalization of PTEN expression was not different between treatment groups in any tissue compartments. Myometrial Ki-67 expression decreased following asoprisnil 25 mg (P < 0.05). Asoprisnil does not induce proliferation of uterine tissues and does not suppress endometrial PTEN expression.

Effects of the Selective Progesterone Receptor Modulator Asoprisnil on Uterine Artery Blood Flow, Ovarian Activity, and Clinical Symptoms in Patients with Uterine Leiomyomata Scheduled for Hysterectomy

Asoprisnil, a novel orally active selective progesterone receptor modulator, is being studied for the management of symptomatic uterine leiomyomata. The exact mechanism of action is not yet discerned. The primary objectives of this double-blind, randomized, placebo-controlled study included evaluation of the effect of asoprisnil on uterine artery blood flow. Furthermore, we assessed effects of asoprisnil on leiomyoma symptoms. Thirty-three premenopausal patients scheduled for hysterectomy due to symptomatic uterine leiomyomata were recruited in four centers and treated with 10 or 25 mg asoprisnil or placebo for 12 wk before surgery. At baseline and before hysterectomy, all patients underwent sonographic assessment to measure impedance to uterine artery blood flow, determined by resistance index and pulsatility index, as well as volumes of largest leiomyoma and uterus. In addition, patients recorded intensity and frequency of menstrual bleeding on a menstrual pictogram. Each asoprisnil treatment was compared with placebo. The increased pulsatility index in both asoprisnil groups and the statistically significantly increased resistance index within the 25-mg asoprisnil group suggest a moderately decreased uterine artery blood flow. Analysis of menstrual pictogram scores showed a statistically significant larger decrease in frequency and intensity of bleeding for both asoprisnil groups compared with placebo. Bleeding was suppressed by asoprisnil 25mg in 91% of patients. Asoprisnil treatment was well tolerated when administered daily for a 12-wk period, and no serious adverse events occurred. Asoprisnil moderately reduced uterine artery blood flow. This effect may contribute in part to the clinical effects of asoprisnil.

Selective progesterone receptor modulator asoprisnil down-regulates collagen synthesis in cultured human uterine leiomyoma cells through up-regulating extracellular matrix metalloproteinase inducer

A recent clinical trial demonstrated that selective progesterone receptor modulator asoprisnil is effective in reducing uterine leiomyoma volume. We investigated the effects of asoprisnil in vitro on the expression of the extracellular matrix (ECM)-remodeling enzymes and collagens in cultured leiomyoma and matching normal myometrial cells. The expression of extracellular matrix metalloproteinase inducer (EMMPRIN), matrix metalloproteinases (MMPs), tissue inhibitors of MMP (TIMPs) and collagens were assessed by western blot analysis. Untreated cultured leiomyoma cells had significantly lower EMMPRIN (P < 0.05), MMP-1 (P < 0.05) and membrane type 1-MMP (MT1-MMP) (P < 0.01) protein contents, but significantly higher TIMP-1 (P < 0.05), TIMP-2 (P < 0.01), type I (P < 0.05) and type III (P < 0.01) collagen protein contents compared with untreated cultured myometrial cells. Treatment with asoprisnil at concentrations > or =10(-7) M for 48 h significantly (P < 0.05) increased EMMPRIN, MMP-1 and MT1-MMP protein contents, and decreased TIMP-1 (P < 0.05), TIMP-2 (P < 0.01), type I (P < 0.01) and type III (P < 0.05 at 10(-7) M; P < 0.01 at 10(-6) M) collagen protein contents in cultured leiomyoma cells compared with control cultures. However, asoprisnil treatment did not affect the protein contents of ECM-remodeling enzymes and collagens in cultured myometrial cells. These results suggest that asoprisnil may reduce collagen deposit in the ECM of cultured leiomyoma cells through decreasing collagen synthesis and enhancing the expression of EMMPRIN, MMPs and TIMPs without comparable effects on cultured myometrial cells.

Selective progesterone receptor modulator asoprisnil induces endoplasmic reticulum stress in cultured human uterine leiomyoma cells

A recent clinical trial (Chwalisz K, Larsen L, Mattia-Goldberg C, Edmonds A, Elger W, Winkel CA. Fertil Steril 87: 1399-1412, 2007) has demonstrated that the selective progesterone receptor modulator asoprisnil efficiently causes the shrinkage of uterine leiomyoma. The present study was conducted to examine whether asoprisnil elicits endoplasmic reticulum (ER) stress-induced apoptosis in cultured human uterine leiomyoma cells. After subculture in phenol red-free DMEM supplemented with 10% FBS for 120 h, cultured cells were stepped down to serum-free conditions with or without graded concentrations of asoprisnil. ER stress-associated and apoptosis-related proteins were assessed by reverse transcription-PCR analysis or Western blot analysis. RNA interference of growth-arrest- and DNA-damage-inducible gene 153 (GADD153) was performed using small interfering RNA. Terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-triphosphate nick end labeling (TUNEL)-positive rates were assessed by TUNEL assay. Compared with untreated control cultures, treatment with 10(-7) M asoprisnil significantly (P < 0.05) increased the protein contents of ubiquitin at 2 h and phospho-double-stranded RNA-activated protein kinase-like ER kinase, phospho-eukaryotic initiation factor 2alpha, activating transcription factor 4, and glucose-regulated protein 78 kDa at 4 h, followed by the significant (P < 0.05) increase in GADD153 protein content at 6 h and cleaved poly(adenosine 5'-diphosphate ribose)polymerase (PARP) at 8 h. RNA interference of GADD153 suppressed protein contents of asoprisnil-induced cleaved PARP, Bax, Bak, GADD34, and tribbles-related protein 3 (TRB3) and TUNEL-positive rate but attenuated asoprisnil-induced reduction in Bcl-2 protein content in cultured leiomyoma cells. These results suggest that asoprisnil elicits ER stress-induced apoptosis in cultured leiomyoma cells and that GADD153 plays a role in asoprisnil-induced apoptosis by modulating the Bcl-2 family of proteins, GADD34, and TRB3.

The effects of the selective progesterone receptor modulator asoprisnil on the morphology of uterine tissues after 3 months treatment in patients with symptomatic uterine leiomyomata

Asoprisnil is a selective progesterone receptor modulator with mixed progesterone agonist/antagonist activity which controls uterine bleeding via an endometrial effect. This study examined full-thickness endometrial, leiomyoma and myometrial morphology in hysterectomy specimens from patients with uterine leiomyomata, after treatment with asoprisnil for 3 months. In this double-blind, randomized, placebo-controlled study, 33 subjects with uterine leiomyomata were randomized to receive asoprisnil 10, 25 mg or placebo for an average of 95 days prior to hysterectomy. Samples of endometrium, myometrium and leiomyoma tissue were subjected to systematic morphological assessment with quantification of mitotic activity. In patients treated with 10 or 25 mg asoprisnil, a unique pattern called 'non-physiologic secretory effect' was evident in endometrium, recognizable through partially developed secretory glandular appearances and stromal changes. Endometrial thickness was decreased, and there were low levels of mitotic activity in endometrial glands and stroma. Unusual thick-walled muscular arterioles and prominent aggregations of thin-walled vessels were present in endometrial stroma, but not in myometrium or non-endometrial vascular beds. Mitotic activity was decreased in leiomyomata. Asoprisnil induces unique morphological changes and is associated with low levels of glandular and stromal proliferation in endometrium, and in leiomyomata. These changes are likely to contribute to the amenorrhoea experienced after exposure to the medication.

A Novel Selective Progesterone Receptor Modulator Asoprisnil (J867) Inhibits Proliferation and Induces Apoptosis in Cultured Human Uterine Leiomyoma Cells in the Absence of Comparable Effects on Myometrial Cells

A Novel Selective Progesterone Receptor Modulator Asoprisnil (J867) Inhibits Proliferation and Induces Apoptosis in Cultured Human Uterine Leiomyoma Cells in the Absence of Comparable Effects on Myometrial Cells

A Novel Selective Progesterone Receptor Modulator Asoprisnil Activates Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand (TRAIL)-Mediated Signaling Pathway in Cultured Human Uterine Leiomyoma Cells in the Absence of Comparable Effects on Myometrial Cells

We previously demonstrated that asoprisnil, a selective progesterone receptor modulator, induces apoptosis of cultured uterine leiomyoma cells. This study was conducted to evaluate whether asoprisnil activates TNF-related apoptosis-inducing ligand (TRAIL)-mediated apoptotic pathway in cultured uterine leiomyoma and matching myometrial cells. After subculture in phenol red-free DMEM supplemented with 10% fetal bovine serum for 120 h, cultured cells were stepped down to serum-free conditions for 24 h in the absence or presence of graded concentrations of asoprisnil. The levels of TRAIL signaling molecules and cellular inhibitors of apoptosis protein were assessed by Western blot analysis. TRAIL contents in untreated cultured leiomyoma cells were significantly (P < 0.01) lower compared with those in untreated cultured myometrial cells. There was no difference in death receptor (DR)4 and DR5 contents between the two types of cells. Asoprisnil treatment significantly (P < 0.05) increased TRAIL, DR4, and DR5 contents in cultured leiomyoma cells in a dose-dependent manner with a cleavage of caspase-8, -7, and -3, and decreased X-linked chromosome-linked inhibitor of apoptosis protein contents. In cultured myometrial cells, however, asoprisnil treatment did not affect either TRAIL signaling molecule or cellular inhibitors of apoptosis protein contents. The concomitant treatment with 100 ng/ml P4 significantly (P < 0.05) reversed asoprisnil-induced increase in DR4 and cleaved poly(adenosine 5'-diphosphate-ribose) polymerase contents in cultured leiomyoma cells. These results suggest that asoprisnil induces apoptosis of cultured leiomyoma cells by activating TRAIL-mediated apoptotic pathway and down-regulating X-linked chromosome-linked inhibitor of apoptosis protein levels in the absence of comparable effects on myometrial cells.

A novel selective progesterone receptor modulator asoprisnil (J867) down-regulates the expression of EGF, IGF-I, TGFβ3 and their receptors in cultured uterine leiomyoma cells

This study was conducted to evaluate the effects of a novel selective progesterone receptor modulator (SPRM) asoprisnil on the expression of growth factors and their receptors and on growth factor-induced proliferation of cultured uterine leiomyoma and matching myometrial cells. The expression of epidermal growth factor (EGF), insulin-like growth factor-I (IGF-I) and transforming growth factor (TGFbeta3) was assessed by immunocytochemistry and semi-quantitative RT-PCR. The expression of phosphorylated EGF receptor (p-EGFR), IGF-I receptor alpha subunit (IGF-IRalpha) and phosphorylated TGFbeta receptor type II (p-TGFbeta RII) was assessed by Western blot analysis. Cell proliferation was assessed by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium assay. Treatment with 10(-7) M asoprisnil decreased EGF, IGF-I and TGFbeta3 mRNA and protein expression as well as p-EGFR, IGF-IRalpha and p-TGFbeta RII protein expression in leiomyoma cells cultured for 72 h. EGF (100 ng/ml), IGF-I (100 ng/ml) and TGFbeta3 (10 ng/ml) increased the number of viable leiomyoma cells cultured for 72 h, whereas the concomitant treatment with 10(-7) M asoprisnil antagonized the growth factor-induced increase in leiomyoma cell proliferation. In cultured myometrial cells, however, asoprisnil affected neither the growth factor and their receptor expression nor the cell proliferation. Asoprisnil inhibits the expression of EGF, IGF-I, TGFbeta3 and their receptors in cultured leiomyoma cells without affecting their expressions in myometrial cells.

A Novel Selective Progesterone Receptor Modulator Asoprisnil (J867) Inhibits Proliferation and Induces Apoptosis in Cultured Human Uterine Leiomyoma Cells in the Absence of Comparable Effects on Myometrial Cells

Asoprisnil, a selective progesterone (P4) receptor (PR) modulator (SPRM) with mixed P4 agonist/antagonist activities, reduces uterine leiomyoma volume in a dose-dependent manner in the presence of follicular phase estrogen concentrations. The evidence from clinical studies suggests that asoprisnil may directly target the uterine leiomyomata. The present study evaluated the effects of asoprisnil on cell proliferation, the expression of apoptosis-related proteins, and apoptosis in cultured human uterine leiomyoma cells and matched normal myometrial cells. PR-A and PR-B expression in the two types of cells was comparatively evaluated. Cell proliferation, proliferating cell nuclear antigen (PCNA)-positive rate, and TUNEL-positive rate were assessed by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium assay, immunocytochemistry, and terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-triphosphate nick end labeling (TUNEL) assay, respectively. The expression of apoptosis-related proteins and PR was assessed by Western blot analysis. Compared with untreated cultures, asoprisnil decreased the number of viable cultured cells, the PCNA-positive rate, and PCNA protein expression in cultured leiomyoma cells. Asoprisnil increased the TUNEL-positive rate, cleaved caspase-3, and cleaved poly(adenosine 5'-diphosphate-ribose) polymerase expression and decreased Bcl-2 protein expression in cultured leiomyoma cells. These effects were dose and time dependent. In cultured myometrial cells, however, asoprisnil did not affect cell proliferation and apoptosis. PR-B expression was elevated in cultured leiomyoma cells compared with cultured myometrial cells, whereas no differences in PR-A expression were noted between the two cell types. These results show that asoprisnil inhibits proliferation and induces apoptosis in cultured uterine leiomyoma cells in the absence of comparable effects on cultured normal myometrial cells, suggesting a cell type-specific effect.

Selective Progesterone Receptor Modulator Asoprisnil (J867) Inhibits Proliferation and Induces Apoptosis in Cultured Uterine Leiomyoma Cells But Not in Cultured Normal Myometrial Cells

It has been demonstrated that progesterone takes a vital role in regulating uterine leiomyoma cell proliferation and apoptosis through up-regulating PCNA and Bcl-2 protein expression and down-regulating TNFα expression in those cells (J Clin Endocrinol Metab 82: 293-299, 83: 2192-2198, 86: 2275-2280). Thus, the present study was conducted to evaluate the effects of the selective progesterone receptor modulator asoprisnil on proliferative activity and apoptosis in cultured uterine leiomyoma cells in comparison with the effects in cultured normal myometrial cells.

Therapeutic potential for the selective progesterone receptor modulator asoprisnil in the treatment of leiomyomata.

Asoprisnil is a novel selective progesterone receptor modulator that exhibits partial agonist and antagonist activities in animals and humans. It demonstrates a high degree of progesterone receptor specificity and tissue selectivity. Although asoprisnil at high doses exhibited some antiglucocorticoid activity in animal models, no antiglucocorticoid effects were observed at therapeutic doses in humans. In male rats, asoprisnil showed mixed androgenic and antiandrogenic properties. Unlike antiprogestins, asoprisnil at high doses exhibited only marginal labor-inducing activity in guinea pigs during midpregnancy and was completely ineffective in inducing preterm parturition. In nonhuman primates, asoprisnil completely eliminated menstrual cyclicity and induced endometrial atrophy. Early clinical studies of asoprisnil in healthy volunteers demonstrated a dose-dependent suppression of menstruation, irrespective of the effects on ovulation, with no change in basal estrogen concentrations and no breakthrough bleeding. Phase 2 studies in subjects with uterine fibroids demonstrated that asoprisnil induced amenorrhea and reduced the volume of the dominant leiomyoma in a dose-dependent manner without altered basal estrogen and with virtually no clinical symptoms of estrogen deprivation. Asoprisnil seems to exhibit a direct inhibitory effect on both the endometrium and leiomyoma. In all studies to date, asoprisnil has maintained a favorable safety and tolerability profile. Thus, asoprisnil has the potential to target the major clinical symptoms of leiomyomata related to both menorrhagia and the size of the tumors and may, therefore, reduce or eliminate the need for surgery.