HE4 is a novel tissue marker for therapy response and progestin resistance in medium- and low-risk endometrial hyperplasia.

BACKGROUND: The aim of the present study was to investigate whether changes in the tissue expression of human epididymis-specific protein 4 (HE4) could predict therapy resistance and relapse after progestin hormone therapy for medium- and low-risk endometrial hyperplasia. METHODS: Endometrial biopsies were obtained from women participating in a multicentre RCT performed according to the CONSORT guidelines; the women were randomly assigned to either LNG-IUS; 10 mg of oral medroxyprogesterone acetate (MPA) administered for 10 days per cycle; or 10 mg of oral MPA administered daily for 6 months. Of the 153 women who completed therapy, 141 had adequate material for immunohistochemistry in pre- and post-treatment biopsies. An antibody to HE4 (clone 12A2 monoclonal IgG1 antibody, Fujirebio Diagnostics, Inc.) was used for the immunohistochemical staining of the pre- and post-treatment biopsies from each participant. The expression of HE4 staining was evaluated by the histological score (H-score) using light microscopy. RESULTS: Changes in the expression of HE4 (H-score) during therapy were related to the therapy group (P<0.001) and therapy response (P<0.001) of the individuals but could not predict relapse (P>0.05). Changes in the intracellular bodies were shown to predict both the therapy response (P=0.038) and relapse (P=0.014). CONCLUSIONS: Changes in the expression of HE4 during progestin therapy regimens can predict therapy response or indicate progestin resistance for medium- and low-risk endometrial hyperplasia.

Down-regulated progesterone receptor A and B coinciding with successful treatment of endometrial hyperplasia by the levonorgestrel impregnated intrauterine system.

OBJECTIVE: To investigate whether regression of endometrial hyperplasia observed after 3 months of treatment with levonorgestrel impregnated intrauterine system device (LNG-IUS) was sustained after 6 months and whether these effects were still occurring synchronously with extinguished expression of progesterone receptors and increased apoptosis. DESIGN: Retrospective population-based observational study. SETTING: Six local hospitals and one university hospital in northern Norway. POPULATION: Patients (n = 41) with low and medium risk endometrial hyperplasia. METHODS: Histopathological treatment response comparing LNG-IUS (n = 25) and standard per oral medroxyprogesterone (n = 16). Expression of progesterone receptor A (PR-A), progesterone receptor B (PR-B), ER-alpha, ER-beta, Bcl-2, BAX, Caspase-3 and metallothionein (MT) were investigated by immunohistochemistry; results were evaluated by a semi-quantitative H-score. MAIN OUTCOME MEASURES: Response to progestin treatment. RESULTS: All the LNG-IUS treated patients had therapy response after 6 months. PR-A and PR-B in glands were almost extinguished for IUD users compared to the oral group. Estrogen receptors were also reduced. Co-existent changes in apoptosis were differently modulated in glands and stroma in the two treatment groups. Bcl-2 was different in glands and stroma in responders and non-responders to oral therapy. CONCLUSION: The study confirms that LNG-IUS can be safely used for 6 months as treatment for endometrial hyperplasia. The clinical effect is accompanied by almost extinguished PR-receptors in glands coinciding with modulation of apoptosis. The results strongly indicate that progestins activate non-classical initiated signaling pathways.

Data on RT-qPCR assay of nuclear progesterone receptors (nPR), membrane progesterone receptors (mPR) and progesterone receptor membrane components (PGRMC) from human uterine endometrial tissue and cancer cells of the Uterine Cervix.

A previous investigation showed that the endometrium normalized in women with endometrial hyperplasia after three months treatment with high dose levonorgestrel IUS (intrauterine system) [1] . The effect was maintained even if immunohistochemical analyses of the endometrium showed that nuclear progesterone receptors (nPRs) were completely downregulated. These observations indicated that some type of non-genomic effect existed [2]. We conducted new investigations of endometrial hyperplasia, now with 6 months low dose levonorgestrel IUS treatment. Again, the growth disturbances were reversed with normalization of the endometrium [3,4]. In the context of these studies, RT-qPCR analyses of the endometrium were performed before and after treatment, to determine expression of nuclear progesterone receptors (nPRA+B and nPRB), membrane progesterone receptors (mPR, α-, ß- and γ-subtypes) and progesterone receptor membrane components (PGRMC1and PGRMC2). The human cervical cell line (C-4 I) [5] with no detectable nPRs [6,7] , was included in the investigation as biological control .The gene expression of nPRs, mPRs and PGRMCs was determined in the logarithmic growth phase. Tissue and cellular mRNA was determined with RT-qPCR and used as a surrogate marker for receptor (protein) expression. The present data are connected to the related article entitled "Expression of nuclear progesterone receptors (nPRs), membrane progesterone receptors (mPRs) and progesterone receptor membrane components (PGRMCs) in the human endometrium after 6 months levonorgestrel low dose intrauterine therapy" [8].

Expression of nuclear progesterone receptors (nPRs), membrane progesterone receptors (mPRs) and progesterone receptor membrane components (PGRMCs) in the human endometrium after 6 months levonorgestrel low dose intrauterine therapy.

The classical steroid receptors (nuclear receptors), including those for progesterone (nPRs), are thoroughly characterized. The knowledge about so-called non-genomic effects, which are mediated by extra-nuclear initiated signals, has increased immensely the last decades. In a previous clinical study of endometrial hyperplasia, we observed that the antiproliferative progestin effect persisted after 3 months treatment with levonorgestrel (LNG) intrauterine system (IUS) even with a complete downregulation of nPRs. This raised the question of what other mechanisms than signaling through nPRs could explain such an observation. In the present study, RT-qPCR was employed to characterize mRNA expression for nPRs, membrane progesterone receptors (mPRs) and progesterone receptor membrane components (PGRMCs) in women (n = 42) with endometrial hyperplasia that received intrauterine low dose LNG for 6 months. At the end of this period endometrial tissue showed that nPRs were virtually completely downregulated (≈ 10 % of baseline) whereas the levels of remaining mPRs, subtype-α, -ß and -γ were 76 %, 59 % and 73 % of baseline, respectively. PGRMC1 was downregulated to 15 % of baseline, in contrast to PGRMC2, which was upregulated to about 30 % above baseline. We used human cancer cells from uterine cervix (C-4I cells) as control. Progesterone caused a concentration-dependent antiproliferative effect but in several and separate studies, we were unable to detect nPRs (immunocytochemistry) in the C-4I cells. The use of RT-qPCR showed that nPRs were undetectable in C-4I cells, in contrast to mPRs and PGRMCs with a distinct mRNA expression. The present study suggests that mPRs and/or PGRMCs preserve the antiproliferative effect of LNG in the human endometrium and are responsible for the concentration-dependent antiproliferative effect of progesterone in C-4I cells.

Early effects of high concentrations of progesterone and mifepristone A gene expression study of endometrial cancer cells (Ishikawa).

Patients with endometrial hyperplasia representing preliminary stages of endometrial cancer have shown to respond to therapy in 100% of the cases when treated with levonorgestrel-impregnated intrauterine device. Anti-proliferative effect has also been reported after application of an anti-progestin impregnated intrauterine device which showed to induce endometrial atrophy. The intention of the present study was to obtain more information of novel therapeutic targets for hormonal treatment in endometrial hyperplasia and endometrial cancers. Gene expression of signaling pathways after stimulation of Ishikawa cells with high doses of progesterone (32 microM) or Mifepristone (32 microM) was performed. After using an oligo microarrays representing 24,650 human genes and 37,580 gene transcripts, 6154 genes remained after pre-processing and filtering. This resulted in a total of 993 up-regulated genes with 189 genes for progesterone and 255 genes for Mifepristone. The 550 down-regulated genes were distributed with 256 genes for progesterone, 127 genes for RU 486. The results showed that genes presenting the epidermal growth factor (EGF)/MAP-kinase pathway were significantly over-represented by progesterone treatment, whereas, by Mifepristone treatment genes involved in the p53 pathway were also up-regulated (data not shown). These genes may be interesting as potential new therapeutic targets in endometrial hyperplasia and endometrial cancer, as candidate genes for therapy response or as candidate markers for tumor progression.

High concentrations of progesterone and mifepristone mutually reinforce cell cycle retardation and induction of apoptosis.

High concentrations of progesterone (PG) and mifepristone (MF) reinforce the effect of each other, reducing the endometrial cancer (Ishikawa) cell densities in vitro. Whether this effect is caused by cell cycle retardation, induction of apoptosis, or a combination of both was questioned. During a 5 days period in the absence of PG, the G(1)/G(0) fraction increased from 60% to 82% . After the first day of exposure with 32 and 95 muM PG the respective G(1)/G(0) fractions increased to 79% and 82% . A similar pattern was evident after exposure to MF. After the first day, MF caused a clear increase in the G(1)/G(0) fraction from 53% (control) to 72% (70 microM MF). In a third series of experiments, PG and MF were combined. After the first day, the G(1)/G(0) fractions were 50% in absence of active agents, 67% in presence of 32 microM PG, 66% in presence of 23 microM MF and 76% when PG (32 microM) and MF (23 microM) were combined. Both PG and MF induced apoptosis, which showed a time- and concentration-dependent pattern. In the control series the % apoptotic Ishikawa cells increased 2 to 3-fold during the experimental period and the effect of PG on apoptosis developed to a maximum after 4-5 days. On the fifth day, the trend was identical in three different assays commonly used to quantify different stages of apoptosis. The fractions of apoptotic cells, in the presence of 70 microM PG, increased from 2.5% to 28.2% (JC-1), from 1.4% to 13.2% (Annexin-FITC) and from 2.8% to 27.7% (DNA fragmentation assay), respectively. After five days, in a separate experiment, the fraction of apoptotic cells, as determined by JC-1 assay was 3.2% in the absence of active agents, 5.0% in the presence of 32 microM PG, 7.3% in the presence of 23 muM MF, and 12.4% in the presence of both PG (32 microM) and MF (23 microM). The present study shows that supraphysiological PG concentrations and high pharmacological concentrations of MF cause cell cycle retardation and induce apoptosis. In combination, PG and MF mutually reinforce these effects.

Levonorgestrel, medroxyprogesterone and progesterone cause a concentration-dependent reduction in endometrial cancer (Ishikawa) cell density, and high concentrations of progesterone and mifepristone act in synergy.

Endometrial hyperplasia is a precursor lesion of endometrial carcinoma. Clinical studies of endometrial hyperplasia have shown that levonorgestrel (LNG) is more therapeutically effective than medroxyprogesterone acetate (MPA). The present pharmacological in vitro study was performed to compare progestin effects on human endometrial cancer (Ishikawa) cells. Supraphysiological concentrations of progesterone (PG) and high concentrations of LNG and MPA were employed to determine the order of potency in reducing cell density. The order of potency was LNG>MPA>PG with respective 50% inhibitory concentrations (IC(50)) of 3.9+/-0.4, 30.4+/-3.4 and 45.3+/-2.7 microM. Mifepristone (MF) is a potent antiprogestin, but was unable to antagonize the PG-induced cell density reduction. For MF concentrations from 0.2 to 70 microM alone, a PG-mimetic effect was observed with an IC(50) value of 19.0+/-1.7 muM. When PG and MF were combined, a marked reinforcement of the effect was seen. These observations indicate that extranuclear initiated signaling pathways are involved in the reduction of endometrial cancer cells exposed to high concentrations of PG and MF.

Prognostic markers for coexistent carcinoma in high-risk endometrial hyperplasia with negative D-score: significance of morphometry, hormone receptors and apoptosis for outcome prediction.

OBJECTIVES: Hysterectomy represents the current routine therapy for high-risk endometrial precancers. More sophisticated methods are needed for treatment decision among women who want to preserve fertility and seriously ill patients. Among women diagnosed with high-risk hyperplasia, approximately 40% show signs of endometrial cancer in the hysterectomy specimen. Thus, more sophisticated methods are needed to select the women at risk. SETTING: University Hospital of Tromsø, Regional Center for Gynecological Oncology in northern Norway. POPULATION: From 1999 to 2004, 258 consecutive patients had endometrial hyperplasia diagnosed by D-score; 57 among these were high-risk cases (D-score < 0) and 10 had coexisting endometrial carcinoma. No further cancers were detected after long-term follow-up (4-10 years). DESIGN: From the initial histological specimens, material from the 10 patients with cancer and from the 13 cases without cancer (high-risk D-score < 0) was analyzed with selected histomorphometric (architectural and nuclear) and immunohistochemical (hormone receptors and apoptotic) features blinded to the investigator. METHOD: Original slides were used for computerized histomorphometry (4-class rule and related procedures). Serial sections from the paraffin embedded material were used for immunohistochemical investigations. Immunohistochemical expression in glands and stroma was evaluated by the semi-quantitative H-score (ER-alpha, ER-beta, PR-A, PR-B, RCAS-1, Bcl-2, BAX, and Caspase-3). RESULTS: The histomorphometric 4-class rule differentiates between presence and absence of cancers with a sensitivity of 80% and specificity of 77%. Several morphometric and immunohistochemical features were significantly different in cases with cancer and hyperplasia. CONCLUSIONS: Histomorphometry seems superior in predicting coexistent carcinoma in high-risk endometrial hyperplasia and should be considered for clinical use.

Intrauterine Progestin Therapy as a New Approach to Premalignant Endometrial Polyps: A Prospective Observational Study.

BACKGROUND/AIM: Endometrial hyperplastic polyps (EHP) may progress to endometrial carcinoma (EC) if left untreated. We aimed to prospectively investigate the efficacy of the low-dose levonorgestrel intrauterine system (LNG-IUS) as therapy for EHP with malignant potential. PATIENTS AND METHODS: In total, 37 women with EHP underwent therapy with LNG-IUS containing 13.5 mg levonorgestrel for six months or 4-10 weeks depending on whether the EHP was characterized (by D-score analysis) as low- to medium-risk (n=33) or high-risk (n=4) of coexistent or future EC. Therapy response was defined as complete clearance of hyperplastic glands in post-therapy endometrial biopsy. RESULTS: All women with low- to medium-risk EHP obtained therapy response, whereas only 1 out of 4 with high-risk EHP responded to therapy. None of the women were diagnosed with EC during the study and no serious adverse events occurred. CONCLUSION: Low-dose LNG-IUS represents a promising therapy for selected women with EHP.

Treatment results of endometrial hyperplasia after prospective D-score classification: a follow-up study comparing effect of LNG-IUD and oral progestins versus observation only.

OBJECTIVES: Three different treatment options for endometrial hyperplasia were evaluated in a prospective long-time follow-up study, comparing effects of intrauterine levonorgestrel impregnated device (LNG-IUD), low oral dose of medroxyprogesterone acetate (MPA) and no treatment (observation only). To select patients with high probability for co-existing or future carcinoma we used the objective morphometric algorithm, D-score, stratifying patients into three different risk groups. As far as we know, this is the first prospective long-time follow-up study in which treatment recommendation and outcome is based on the D-score assessment. METHODS: From a total of 370 patients initially diagnosed with endometrial hyperplasia from eight different hospitals in North Norway, 258 were available for long-time follow-up. After D-score classification, one of three different treatment options was chosen: LNG-IUD, low oral dose of MPA or observation only. Follow-up controls were performed and biopsies taken in the local hospitals. RESULTS: Among the 370 investigated cases with endometrial hyperplasia, only ten endometrial cancers were detected at the entrance of the study, all belonging to the high risk group (D-score <0). No further cancers were detected during follow-up, irrespective of risk group. After 6 months treatment with LNG-IUD proved significantly superior to oral treatment (p=0.001 for D-score >1 and p=0.003 for D-score 0-1 groups) and observation only (p=0.001 for D-score >1 and p=0.001 for D-score 0-1 groups). After 56 to 108 months the LNG-IUD proved significantly superior to oral treatment and to the observation group. Comparison of oral therapy to observation only showed no significant differences, neither after 6 months nor after long-time observation. CONCLUSIONS: LNG-IUD is the optimal treatment for endometrial hyperplasia. Outcome after oral low-dose MPA regimen is comparable to expectation.

Gene expression in endometrial cancer cells (Ishikawa) after short time high dose exposure to progesterone.

The potent antiproliferative effect of progestins has been utilized in clinical regimens for treatment of endometrial proliferative disorders. The progestin infiltrated intrauterine device used as therapy for endometrial carcinoma as well as endometrial hyperplasia yields a hundred-fold increase of local progestin concentration in the endometrium compared to that of oral treatment. The genetic basis for the complex effects of high dose progestins and the different signalling pathways regulated by these genes have never been accurately surveyed. The aim of the present study was to determine the gene expression pattern in highly differentiated endometrial cancer cells (Ishikawa) after short time exposure to high progesterone doses. In eight independent experiments, cells were treated with progesterone (30microg/ml) for 4h and gene expression was compared to that of untreated cells, which served as controls. Microarray analysis revealed 247 differentially expressed genes of which 126 were up-regulated and 121 were down-regulated. Of these, 135 genes are known to be involved in biological processes like cell cycle, cell proliferation and differentiation, developmental processes, immune responses, intracellular protein traffic and transport. Our study shows that microarray analysis can detect relevant gene expression changes in endometrial cells treated with progestin, including those involved in several alternative transcriptional factors and signalling pathways. Many of the differentially expressed genes were not previously known to be affected by progesterone or have unknown biological functions. Characterization of these genes may give new insights into molecular responses to treatment with high progesterone doses. Alternative signalling pathways for progesterone, rather than the classical steroid receptors pathways are also suggested.

Regression of latent endometrial precancers by progestin infiltrated intrauterine device.

PTEN tumor suppressor inactivation is the earliest step in endometrial carcinogenesis, occurring in morphologically unremarkable endometrial glands in half of normal women. We test the hypothesis that sex hormones positively or negatively select for these "latent precancers" by examining their emergence, persistence, and regression rates under differing hormonal conditions. Perimenopausal and postmenopausal women had an intake endometrial biopsy and underwent hormonal therapy with progestin-impregnated intrauterine device (IUD; n = 21), cyclic oral progestins (n = 28), or surveillance only (n = 22) with follow-up biopsies. For comparison, premenopausal naturally cycling endometrial biopsies were studied as single time points in 87 patients and multiple surveillance time points in 34 patients. Biopsies in which any PTEN protein-null glands were found by immunohistochemistry were scored as containing a latent endometrial precancer. All groups had a similar proportion of latent precancers at intake but differed after therapy. Emergence rates were highest (21%) for the naturally cycling premenopausal group compared with just 9% for untreated perimenopausal women. The IUD group had the highest rate of regression, with a 62% pretherapy and 5% post-therapy rate of latent precancers. This contrasted to nonsignificant changes for the oral progestin and untreated control groups. Delivery of high doses of progestins locally to the endometrium by IUD leads to ablation of preexisting PTEN-inactivated endometrial latent precancers and is a possible mechanism for reduction of long-term endometrial cancer risk known to occur in response to this hormone.

Low-dose LNG-IUS as Therapy for Endometrial Hyperplasia. A Prospective Cohort Pilot Study.

BACKGROUND/AIM: Progestin therapy has been accepted as therapy for low- and medium-risk endometrial hyperplasia. The aim of this study was to investigate the efficacy of the low-dose levonorgestrel-impregnated intrauterine system (LNG-IUS) 13.5 mg (Jaydess®, Bayer Pharmaceuticals, Berlin, Germany) as therapy for endometrial hyperplasia. PATIENTS AND METHODS: A total of 21 women with histologically-verified endometrial hyperplasia were prospectively treated with LNG-IUS Jaydess. Therapy duration was 6 months (n=16) or 3-6 weeks (n=5) depending on individual risk (low- and medium-risk versus high-risk) for co-existent or future endometrial carcinoma. Paired endometrial biopsies were sampled prior to and after therapy and classified according to the WHO94 classification system and D-score. RESULTS: All women with low- and medium risk endometrial hyperplasia had-therapy response. In the group of women with high-risk endometrial hyperplasia only 40% (two out of five) obtained a therapy response. CONCLUSION: Low-dose LNG-IUS Jaydess was proven to be an excellent therapy option for low- and medium-risk endometrial hyperplasia. For patients with high-risk endometrial hyperplasia hysterectomy or LNG-IUS therapy under close surveillance is advised.

Urinary cyclic GMP after treatment of gynecological cancer. A prognostic marker of clinical outcome.

BACKGROUND: The search for biological markers to predict malignant disease and its recurrence, or to monitor the effectiveness of treatment is a continuous process in medicine. Several years ago, urinary excretion of cGMP in urine was found to be a sensitive predictor in the follow-up of ovarian cancer and of monitoring treatment of cancer of the uterine cervix. PATIENTS AND METHODS: In the present study, 27 patients with gynecological cancer, including cancer of the uterine cervix (n=13), cancer of the uterine corpus (n=8) and cancer of the ovaries (n=6), were monitored for 10 years. Blood and urinary samples were taken before primary treatment (baseline sample) and three months thereafter (three-month sample). The serum levels of CEA, CA-125 and PIIINP and urine excretion of cGMP and cAMP were determined. Creatinine levels in serum and urine were employed to determine renal clearance. RESULTS: After 10 years' observation of women with cancer of the uterine cervix, seven patients showed no relapse and cGMP levels in baseline samples and three-month samples were 36.8+/-4.1 and 24.9+/-4.4 nmol cGMP/micromol creatinine (mean+/-SEM, p<0.01), respectively. The levels in patients (n=6) with relapse after 10 years' observation were 32.8+/-4.0 (baseline sample) and 43.5+/-4.2 (three-month sample) nmol cGMP/micromol creatinine (mean+/-SEM, p<0.02). Among the patients treated for cancer of the uterine corpus (n=9), none showed recurrent disease within the observation period of 10 years. The cGMP levels fell from 37.9+/-6.3 (baseline sample) to 22.3+/-2.3 (three-month sample) nmol cGMP/micromol creatinine (p<0.005). In the patients with ovarian cancer (n=6), 4 patients relapsed during the observation period of 10 years. In these women the cGMP levels increased from 34.5+/-2.7 (baseline sample) to 46.3+/-4.7 nmol cGMP/micromol creatinine whilst in both patients without relapse the levels decreased from 31.8 (range: 26.5-37.1) to 27.3 (range: 25.7-28.8) nmol cGMP/micromol creatinine, respectively. The changes in levels of cAMP, CEA, CA-125 and PIINP did not show statistically significant differences. Early changes in cGMP levels appear to predict long-term prognosis in gynecological cancers.

Prediction of Relapse After Therapy Withdrawal in Women with Endometrial Hyperplasia: A Long-term Follow-up Study.

AIM: To investigate whether risk of relapse of endometrial hyperplasia persists many years after successful primary therapy and whether clinical or biological markers observed at primary diagnosis may predict relapse. MATERIALS AND METHODS: A series of 57 women with endometrial hyperplasia received levonorgestrel-impregnated intrauterine system or oral progestin for three months during 1998-2000. Index biopsies were classified according to WHO1994 and D-score systems, and immunohistochemical staining for estrogen receptor α (ERα), estrogen receptor ß (ERß), progesterone receptor A (PRA), progesterone receptor B (PRB), B-cell lymphoma 2/apoptosis regulator (BCL2), BCL2-associated X protein/apoptosis regulator (BAX), paired box 2 (PAX2), and phosphatase and tensin homolog (PTEN) reported as H-scores. RESULTS: Over a follow-up of 157.8 months, 23% (10/43) of patients experienced relapse. No correlation with age, body mass index, parity, WHO94 classification, or D-score was found. Only PRA (p=0.004) and PRB (p=0.038) showed certain correlation with relapse. CONCLUSION: Endometrial hyperplasia recurs many years after successful progestin therapy. Increased expression of PRB and reduced expression of PRA significantly correlated with relapse. Our results support the importance of continuous endometrial protection and the need for new clinical surveillance guidelines.

Expression of PAX2 and PTEN Correlates to Therapy Response in Endometrial Hyperplasia.

AIM: To investigate if a levonorgestrel-impregnated intrauterine system (LNG-IUS) was more efficient compared to oral progestin in the clearance of the paired box 2 gene (PAX2) - and phosphatase and tensin homolog (PTEN)-null endometrial glands and assess the significance of PAX2- and PTEN-null glands as markers for therapy response in endometrial hyperplasia. PATIENTS AND METHODS: Immunohistochemical staining using antibodies against PAX2 and PTEN was performed in 141 pre- and post-treatment endometrial biopsies comparing the effect of LNG-IUS, 10 mg medroxyprogesterone acetate (MPA) taken continuously, or 10 mg MPA taken 10 days per cycle for six months. PAX2- and PTEN-null glands were investigated by light microscopy in pre-and post-treatment biopsies. RESULTS: Clearance of PAX2- and PTEN-null glands was significantly more efficient by LNG-IUS compared to oral MPA (p<0.000 and p=0.008, respectively) and significantly related to therapy response (p<0.000 and p=0.002, respectively).

Non-genomic effects of progestins--inhibition of cell growth and increased intracellular levels of cyclic nucleotides.

The anti-proliferative effect of progestins was studied in human transformed cell lines from the uterine cervix (C-4I, C33A and Me-180). Progestins caused a concentration-dependent inhibition of proliferation. The maximum tested concentration (2.6-3.2 microM) inhibited C-4I cell growth by the following order of potency: progesterone (56%) > medroxyprogesterone (38%) > megestrol acetate (25%). The sensitivity, expressed as I(25) (the concentration that caused 25% inhibition of growth), showed the same order: progesterone (7.7 nM) > medroxyprogesterone (78 nM) > megestrol acetate (570 nM). The intracellular levels of cGMP and cAMP were elevated and the cellular export of these cyclic nucleotides was inhibited by a similar order of potency. The C-4I cell line was devoid of progesterone-, estrogen-, androgen- and glucocorticoid-receptors. In addition, the antiprogestins mifepristone, onapristone and ZK-112993 did not block the anti-proliferative effect of progesterone. On the other hand, antiprogestins (2.3 nM) appeared to have some progesterone-like ("mimetic") activity with inhibition of C-4I cell growth; mifepristone (11%), onapristone (12%) and ZK-112993 (16%). The observed effects of progestins and antiprogestins on C-4I cells were also presented in C33A cells (16% androgen receptor positive) and Me-180 cells (22% progesterone receptor positive, 9% androgen receptor positive and 17% glucocorticoid receptor positive). This study suggests that a non-genomic mechanism contributes to the anti-proliferative effect of progestins.

Non-genomic cell growth inhibition by progesterone. cell cycle retardation and induction of cell death.

BACKGROUND: Non-genomic mechanisms have been proposed to play a role in progesterone-dependent cell growth inhibition. MATERIALS AND METHODS: The human cell line C-4I, derived from a squamous carcinoma of the uterine cervix, was progesterone receptor-negative. The culture medium contained 10% (v/v) fetal calf serum and the cells, growing in monolayer, were exposed to various progesterone concentrations. Flow cytometry and morphometry were employed to assess the effects. RESULTS: Progesterone caused a concentration-dependent growth inhibition with an IC50 value of 2.06 +/- 0.46 microM (mean value +/- SEM, n = 4). At 320 microM no viable and attached cells were left. Two mechanisms appeared to be responsible for the effect. Firstly, the cells accumulated in the G1/G0-phase indicating a cell cycle-specific arrest. Secondly, progesterone induced cell death with apoptosis and necrosis. Morphometric analysis showed that progesterone caused a marked reduction in the nuclear size, compatible with apoptosis. CONCLUSION: The present results show that progesterone exerts non-genomic effect(s) by reducing the input of and accelerating the exit of cells from the C-4I cell population.

Levonorgestrel-impregnated Intrauterine device reduces occurrence of hyperplastic polyps: a population-based follow-up cohort study.

BACKGROUND: The main objective was to investigate if occurrence of hyperplastic polyps was reduced by use of the levonorgestrel-impregnated intrauterine system (LNG-IUS, Mirena®; Bayer) and if the LNG-IUS was more effective compared to oral medroxyprogesterone acetate (MPA) or observation-only. PATIENTS AND METHODS: Patients (N=59) with hyperplastic polyps were given LNG-IUS, 10 mg oral MPA taken 10 days per cycle, or had observation-only for six months. Diagnosis of histological specimens was performed by light microscopy according to the WHO classification and D-score prior to and after six months therapy. RESULTS: No polyps were found in women treated with LNG-IUS (18/18). Five women treated with cyclic MPA (5/20, 25%) and two (2/21, 9%) with observation had normal endometrium without polyps after six months. CONCLUSION: No former study has shown that LNG-IUS is effective at reducing the occurrence of hyperplastic endometrial polyps. The effect is superior to that of oral progestin and observation-only.