Progesterone Receptor A Expression Research Articles

Expression of oestrogen and progesterone receptor and intermediate filament proteins in the oviduct of mares with endometrosis

Equine endometrosis is one of the major causes of equine infertility, in the course of which periglandular fibrosis signs occur in the endometrium. As an oviduct is a key place of early embryo development, we hypothesized that loss of contact between mucosal cells and perturbation in hormonal action may coexist in the uterus and oviducts. Thus, this study aimed to investigate the expression of the intermediate filaments (vimentin and desmin) as well as the estrogen receptor alpha (ERα) and progesterone receptor A (PRA) in the stroma and epithelia of endometrium and oviduct in healthy mares and these with endometrosis. Out of 56 culled-in slaughterhouse mare endometrium samples were annotated in two groups (i) healthy endometrium (n=26) and endometrium with signs of moderate and severe endometrosis (n=20). The expression of vimentin, desmin, ERα, and PRA was investigated immunohistochemically and compared between the above groups as well as between the phase of the estrous cycle. The expression of both vimentin and desmin was higher in the endometrial stroma of endometrosis group compared to healthy endometrium. The expression of ERα was higher in the healthy endometrial stroma and luminal epithelium during the follicular phase than luteal, however, no differences were noted in endometrium of mares with endometrosis. Moreover, PRA expression was significantly higher in the stoma oviduct during the follicular phase than luteal. It seems possible that mucosal cells through their altered interactions may support the occurrence of moderate and severe endometrosis. In addition, the oviduct appears to be less sensitive to hormonal changes than the uterus. The changed expression of intermediate filaments and steroid hormones may be some of the leading factors which can contribute to the oviduct functional status in endometrosis.

E. coli Nissle 1917 ameliorates mitochondrial injury of granulosa cells in polycystic ovary syndrome through promoting gut immune factor IL-22 via gut microbiota and microbial metabolism.

Gut microbiota and its metabolites have regulatory effects on PCOS related ovarian dysfunction and insulin resistance. Escherichia coli Nissle 1917 (EcN) is a genetically controlled probiotic with an excellent human safety record for improving gut microbiome metabolic disorders and immune system disorders. Here we focused to explore the application and effect of probiotic EcN on the gut microbiota-metabolism-IL-22-mitochondrial damage axis in PCOS. PCOS mice were constructed with dehydroepiandrosterone (DHEA) and treated with EcN, FMT or IL-22 inhibitors. Clinically control and PCOS subjects were included for further analysis. Serum and follicular fluid supernatant levels of sex hormones, insulin, glucose, cholesterol, and inflammatory factors were detected by ELISA and biochemical reagents. The pathological changes of ovarian tissues were observed by HE staining. The JC-1 level and COX4 gene expression in granulosa cells was detected by ELISA and RT-qPCR. The expressions of progesterone receptor A (PR-A), LC3II/I, Beclin1, p62 and CytC were detected by western blot. The number of autophagosomes in granulosa cells was observed by electron microscopy. 16S rRNA and LC-MS/MS were used to analyze the changes of gut microbiota and metabolism. EcN promoted the recovery of sex hormone levels and ovarian tissue morphology, promoted the expression of IL-22, COX4 and PR-A in granulosa cells, and inhibited mitophagy in PCOS mice. EcN decreased the number of gut microbiota, and significantly increased the abundance of Adlercreutzia, Allobaculum, Escherichia-Shigella and Ileibacterium in PCOS mice. EcN improved metabolic disorders in PCOS mice by improving Amino sugar and nucleotide sugar metabolism pathways. IL-22 was positively associated with Ileibacterium, Adlercreutzia and Progesterone, negatively associated with RF39, Luteinizing hormone, Testosterone, N-Acetylglucosamin, L-Fucose and N-Acetylmannosamin. FMT reconfirmed that EcN ameliorated mitochondrial damage in granulosa cells of PCOS mice by gut microbiota, but this process was blocked by IL-22 inhibitor. Clinical trials have further demonstrated reduced IL-22 levels and mitochondrial damage in granulosa cells in PCOS patients. EcN improved IL-22 level and mitochondrial damage of granulosa cells in PCOS mice by promoting the recovery of sex hormone levels and ovarian tissue morphology, inhibiting the amount of gut microbiota, and promoting amino sugar and nucleotide sugar metabolism.

Expression of Progesterone Receptor A as an Independent Negative Prognosticator for Cervical Cancer.

The role of progesterone receptor A (PRA) for the survival outcome of cervical cancer patients is ambiguous. In mouse models, it has been shown that PRA plays a rather protective role in cancer development. The aim of this study was to assess its expression by immunohistochemistry in 250 cervical cancer tissue samples and to correlate the results with clinicopathological parameters including patient survival. PRA expression was positively correlated with the International Federation of Gynecology and Obstetrics (FIGO) classification scores. PRA was significantly overexpressed in adenocarcinomas compared to squamous epithelial carcinoma subtypes. Correlation analyses revealed a trend association with the HPV virus protein E6, a negative correlation with p16 and a positive correlation with EP3. PRA expression was also associated with the expression of RIP140, a transcriptional coregulator that we previously identified as a negative prognostic factor for survival in cervical cancer patients. Univariate survival analyses revealed PRA as a negative prognosticator for survival in patients with cervical adenocarcinoma. Multivariate analyses showed that simultaneous expression of RIP140 and PRA was associated with the worst survival, whereas with negative RIP140, PRA expression alone was associated with the best survival. We can therefore assume that the effect of nuclear PRA on overall survival is dependent upon nuclear RIP140 expression.

Fetal Exosomal Platelet-activating Factor Triggers Functional Progesterone Withdrawal in Human Placenta.

In most mammals, labor is heralded by the withdrawal of progesterone. In humans, circulating progesterone levels increase as gestation advances while placental expression of progesterone receptor A (PR-A) declines. As a result of PR-A downregulation, the non-canonical NF-κB pathway is activated, an event implicated in triggering labor. Here, we sought to identify fetal-derived mediator(s) that represses placental PR-A in human placenta leading to activation of pro-labor signaling. Lipidomic profiling demonstrated enrichment of platelet-activating factor (PAF) in exosomes originating from the human fetus. Exposure of primary cytotrophoblasts to fetal exosomes from term pregnancies reduced PR-A expression by > 50%, and PAF also reduced PR-A message levels in a dose-dependent manner. Notably, fetal exosomes from preterm pregnancies had lower PAF levels and no effect on PR-A expression. Synthetic PAF-induced DNA methylation increases by 20% at the PR-A promoter, leading to recruitment of corepressors and downregulation of PR-A in cytotrophoblast. Furthermore, suppression of PR-A by PAF-stimulated expression of the pro-labor genes, corticotropin-releasing hormone (CRH) and cyclooxygenase-2 (COX-2), which was reversed by disruption of the DNA methyltransferases 3B and 3L. Taken together, PAF represents a novel fetal-derived candidate for initiation of labor by stimulating methylation and repression of PR-A and activating pro-labor signaling in trophoblast.

Effects of hormone replacement therapy on endometrial hormone concentrations and progesterone receptor expression in recurrent pregnancy loss: a self-controlled study

Aim To investigate the differential effects of endometrial preparation approaches, natural cycle (NC) and hormone replacement therapy (HRT), on the endometrial hormone conditions in patients with recurrent pregnancy loss (RPL). Methods 42 RPL patients were recruited, and a self-controlled trial was conducted to compare the effectiveness of NC to HRT on the same patient. The estradiol (E2) and progesterone (P) levels in both serum and endometrial tissue were measured in NC and HRT, respectively. Meanwhile, the expression levels of endometrial progesterone receptor A (PRA) and progesterone receptor B (PRB) were also compared between NC and HRT cycles during the window of receptivity. All statistical analyses were performed using GraphPad Prism 5, and data were averaged across subjects and tested for significance by pair-samples t-test. Results Hormone replacement slightly decreased serum E2 and P levels (0.9- and 0.8-fold in average, respectively), significantly elevated endometrial E2 and P (2.1- and 14.5-fold in average, respectively), and reduced endometrial E2/P ratio (0.34-fold in average) compared to the NC condition. However, no correlation was found between serum and endometrial hormone concentrations. Further, the PRA/PRB ratios of both stromal and glandular cells were comparable between HRT and NC conditions, even though stromal PRA expression was slightly elevated by HRT compared to NC (1.63±0.96 vs 1.18±0.99, p =.0173). Conclusion The effects of HRT for endometrial preparation are similar or slightly superior to NC in RPL patients.

Correlation of NRF2 and progesterone receptor and its effects on ovarian cancer biology.

PurposeThis study aimed to investigate the potential prognostic impact of nuclear factor erythroid 2-related factor 2 (NRF2) and progesterone receptor A (PRA)/progesterone receptor B (PRB) in ovarian cancer patients which might be the rationale for putative new treatment strategies.Patients and methodsThe presence of NRF2 and PRA/PRB was investigated in 156 ovarian cancer samples using immunohistochemistry (IHC). Staining of NRF2 and PRA/PRB was rated using the semi-quantitative immunoreactive score (IR score, Remmele’s score) and correlated to clinical and pathological data. NRF2 and PRA/PRB expression were compared with respect to the overall survival (OS).ResultsNRF2 staining was different in both, the cytoplasm and nucleus between the histological subtypes (p=0.001 and p=0.02, respectively). There was a significant difference in the PRA expression comparing all histological subtypes (p=0.02). Histological subtypes showed no significant differences in the PRB expression. A strong correlation of cytoplasmic NRF2 and PRA expression was detected (cc=0.247, p=0.003) as well as of cytoplasmic NRF2 and PRB expression (cc=0.25, p=0.003), confirmed by immunofluorescence double staining. Cytoplasmic NRF2 expression was associated with a longer OS (median 50.6 vs 32.5 months; p=0.1) as it was seen for PRA expression (median 63.4 vs 33.1 months; p=0.08), although not statistically significant. In addition, high PRB expression (median 80.4 vs 32.5 months; p=0.04) and concurrent expression of cytoplasmic NRF2 and PRA were associated with a significantly longer OS (median 109.7 vs 30.6 months; p=0.02). The same relationship was also noted for NRF2 and PRB with improved OS for patients expressing both cytoplasmic NRF2 and PRB (median 153.5 vs 30.6 months; p=0.009). Silencing of NFE2L2 induced higher mRNA expression of PGR in the cancer cell line OVCAR3 (p>0.05) confirming genetic interactions of NRF2 and PR.ConclusionIn this study, the combination of cytoplasmic NRF2 and high PRA/PRB expression was demonstrated to be associated with improved overall survival in ovarian cancer patients. Further understanding of interactions within the NRF2/AKR1C1/PR pathway could open new additional therapeutic approaches.

Progesterone receptor A promotes invasiveness and metastasis of luminal breast cancer by suppressing regulation of critical microRNAs by estrogen

Distal metastasis of luminal breast cancer is frequent and incurable, yet the metastasis mechanisms are poorly understood. Estrogen, even at postmenopausal concentrations, suppresses invasiveness of luminal breast cancer cells through the estrogen receptor (ER). Invasive tumors overexpress the short progesterone receptor A (PR-A) isoform. Even at postmenopausal concentrations, progesterone activates PR-A, inducing invasiveness by counteracting estrogen's effects, particularly when cells are hypersensitized to progesterone by PR-A overexpression. To interrogate the role of this cross-talk in metastasis, we investigated selective cross-talk mechanisms of PR-A with ER. We developed a quantitative PCR-based lymph node infiltration assay to address the slowness of metastasis of tumor xenografts. We found that 15 microRNAs (miRNAs) are regulated by progesterone via PR-A, but not the longer PR-B isoform, with increased progesterone sensitivity when PR-A was overexpressed. Two of these miRNAs whose induction (miR-92a-3p) or repression (miR-26b-5p) by estrogen was suppressed by progesterone plus PR-A were critical for the PR-A-ER cross-talk causing a gene-regulatory pattern of invasiveness and metastasis and complete rescue of invasiveness in vitro Constitutive expression of miR-92a-3p or inhibition of miR-26b-5p profoundly suppressed metastasis. Finally, in primary breast tumors, PR-A expression was correlated negatively with miR-92a-3p expression and positively with miR-26b-5p expression. Therefore, hormonal cross-talk of PR-A with ER is probably a fundamental mechanism that enables metastasis of luminal breast cancer. Moreover, miRNA biomarkers of hyperactive PR-A may help predict metastatic potential of luminal breast tumors. Further, miR-92a-3p and miR-26b-5p may reveal target pathways for selective intervention to suppress hormone-regulated metastasis, both pre- and postmenopause.

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

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. 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 β (ERβ), 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. 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. 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.

Effect of menopause on hormonal receptors in ampullae of the fallopian tube with a special reference to the p53 signature.

ObjectivesAge-related changes in the expression of hormonal receptors have not been well examined in the fallopian tube (FT). We herein report the effect of menopause on the hormone receptors in ampullae of the FTs (AFTs), in comparison with cortical inclusion cysts (CICs) of the ovary.MethodsA total of 84 AFTs and 16 fimbriae of FTs, which were obtained from 26 premenopausal and 58 postmenopausal women; and 27 postmenopausal CICs were immunohistochemically studied for the expression of p53, Ki-67, estrogen receptor-alpha (ER-α), and progesterone receptor A (PRA). Apoptotic cells were identified using a TUNEL assay.ResultsPostmenopausal AFTs showed a significantly lower labeling index (LI) for Ki-67 (P<0.001), apoptosis (P=0.03), and PRA (P<0.001) than premenopausal AFTs. No significant correlation with immunohistochemical markers was found in premenopausal AFTs, but the LI for PRA was positively correlated with that for Ki-67 (P=0.004) and inversely with that for p53 (P=0.023) in postmenopausal AFTs. The expression of immunohistochemical markers was closely correlated between ampullae and fimbriae of the FT. The p53 signature (p53S) was detected in five postmenopausal AFTs (mean age: 70.2 years) and was not detected in any CICs. The immunohistochemical profile of p53S was low expression of Ki-67, apoptosis, and PRA, and high expression of ER-α. The expression of PRA in CICs was significantly higher than that in AFTs (P=0.001).ConclusionThe expression of PRA was significantly lower in postmenopausal AFTs than in premenopausal AFTs, whereas the expression of PRA was well preserved in postmenopausal CICs.

Decreased epithelial progesterone receptor A at the window of receptivity is required for preparation of the endometrium for embryo attachment.

The precise timing of progesterone signaling through its cognate receptor, the progesterone receptor (PGR), is critical for the establishment and maintenance of pregnancy. Loss of PGR expression in the murine uterine epithelium during the preimplantation period is a marker for uterine receptivity and embryo attachment. We hypothesized that the decrease in progesterone receptor A (PGRA) expression is necessary for successful embryo implantation. To test this hypothesis, a mouse model constitutively expressing PGRA (mPgrALsL/+) was generated. Expression of PGRA in all uterine compartments (Pgrcre) or uterine epithelium (Wnt7acre) resulted in infertility with defects in embryo attachment and stromal decidualization. Expression of critical PGRA target genes, indian hedgehog, and amphiregulin (Areg), was maintained through the window of receptivity while the estrogen receptor target gene, the leukemia inhibitory factor (Lif), a key regulator of embryo receptivity, was decreased. Transcriptomic and cistromic analyses of the mouse uterus at day 4.5 of pregnancy identified an altered group of genes regulating molecular transport in the control of fluid and ion levels within the uterine interstitial space. Additionally, LIF and its cognate receptor, the leukemia inhibitory factor receptor (LIFR), exhibited PGR-binding events in regions upstream of the transcriptional start sites, suggesting PGRA is inhibiting transcription at these loci. Therefore, downregulation of the PGRA isoform at the window of receptivity is necessary for the attenuation of hedgehog signaling, transcriptional activation of LIF signaling, and modulation of solutes and fluid, producing a receptive environment for the attaching embryo.

Progesterone Receptor A Stability Is Mediated by Glycogen Synthase Kinase-3β in the Brca1-deficient Mammary Gland

Germ line mutations of the BRCA1 gene increase the risk of breast and ovarian cancer, but the basis of this tissue-specific tumor predisposition is not fully understood. Previously, we reported that the progesterone receptors are stabilized in Brca1-deficient mammary epithelial cells, and treating with anti-progesterone delays mammary tumorigenesis in Brca1/p53 conditional knock-out mice, suggesting that the progesterone has a critical role in breast carcinogenesis. To further explore how the stability of progesterone receptor is modulated, here, we have found that glycogen synthase kinase (GSK)-3β phosphorylation of progesterone receptor-A (PR-A) facilitates its ubiquitination. GSK-3β-mediated phosphorylation of serine 390 in PR-A regulates its subsequent ubiquitination and protein stability. Expression of PR-A(S390A) mutant in the human breast epithelial cells, MCF-10A, results in enhanced proliferation and formation of aberrant acini structure in the three-dimensional culture. Consistently, reduction of phosphorylation of serine 390 of PR-A and GSK-3β activity is observed in the Brca1-deficient mammary gland. Taken together, these results provide important aspects of tissue specificity of BRCA1-mediated suppression of breast carcinogenesis.

Expression of PRB, FKBP52 and HB-EGF Relating with Ultrasonic Evaluation of Endometrial Receptivity

BackgroundTo explore the molecular basis of the different ultrasonic patterns of the human endometrium, and the molecular marker basis of local injury.Methodology/Principal FindingsThe mRNA and protein expression of FKBP52, progesterone receptor A (PRA), progesterone receptor B (PRB), and HB-EGF were detected in different patterns of the endometrium by real-time RTPCR and immunohistochemistry. There were differences in the mRNA and protein expression of FKBP52, PRB, and HB-EGF in the triple line (Pattern A) and homogeneous (Pattern C) endometrium in the window of implantation. No difference was detected in PRA expression. After local injury, the mRNA expression of HB-EGF significantly increased. In contrast, there was no difference in the mRNA expression of FKBP52, PRB, or PRA. The protein expression of FKBP52, PRB, and HB-EGF increased after local injury. There was no difference in the PRA expression after local injury.ConclusionsPRB, FKBP52, and HB-EGF may be the molecular basis for the classification of the ultrasonic patterns. HB-EGF may be the molecular basis of local injury. Ultrasonic evaluation on the day of ovulation can be effective in predicting the outcome of implantation.

The expression of immunohistochemical markers estrogen receptor, progesterone receptor, Her-2-neu, p53 and Ki-67 in epithelial ovarian tumors and its correlation with clinicopathologic variables

This study aims to evaluate the expression of estrogen receptor alpha (ER α), progesterone receptor A (PRA), Her-2-neu, p53, and Ki-67 in epithelial ovarian tumors and their correlation with various clinicopathologic variables. This study included 60 consecutive cases of epithelial ovarian tumors. Sections of 4 μm were taken from paraffin embedded tissue blocks for immunohistochemistry (IHC). Statistical analysis was done using Chi square test, ANOVA. ER α had lower expression in benign (29%) and PRA higher expression in malignant (63.6%) tumors. ERα, PRA had higher expression in serous (72.72%, 57.14%), postmenopausal (81.8%, 71.42%), advanced stage (63.63%, 52.38%), grade 3 (45.45%, 38.09%), and tumors with ascites (90.90%, 85.7%). Her-2-neu, p53 were negative in benign and higher in malignant (21%, 57.6%), serous (71.42%, 57.89%), grade 3 (57.14%, 31.57%), and tumors with ascites (85.7%, 84.21%). Ki-67 had a significant higher expression in malignant (48.6 ± 26.76), serous (55.43 ± 27.85), and grade 3 tumors (68 ± 22). CA-125 levels were significantly higher in malignant, serous, advanced stage, grade 3 and ER α, Her-2-neu and p53 positive tumors. ERα, PRA expression in tumors with adverse prognostic factors support the mitogenic role of estrogen and estrogenic regulation of PR. Her-2-neu and p53 expression only in malignant tumors suggest their carcinogenic role and aid in the differentiation of borderline and malignant tumors. Higher Ki-67 in tumors with adverse prognostic factors would help in prognostication and differentiation. Lack of co-expression of markers proves the extreme heterogeneity of ovarian tumors. These markers may aid in differentiation and prognostication of ovarian tumors.

Compartmentalized secretory leukocyte protease inhibitor expression and hormone responses along the reproductive tract of postmenopausal women

Immunity and hormonal responses in the reproductive tissues of postmenopausal women are poorly understood. Secretory leukocyte protease inhibitor (SLPI), a multifunctional antimicrobial protein expressed at mucosal surfaces, is thought to play a key role in infectious and inflammatory contexts. The aim of this study was to measure SLPI production along the female reproductive tract in postmenopausal women with and without hormonal treatment. We additionally quantified estrogen receptor alpha (ERα) and progesterone receptor A (PRA) in these tissues. Expression of SLPI was decreased in the vagina and ectocervix of women under hormonal treatment. Endocervical ERα mRNA expression was increased while this did not reach significance at the protein level. SLPI expression in the endometrium was not influenced by hormonal treatment. We observed attenuated ERα expression in the cervix and endometrium of hormonally treated women, whereas vaginal expression was increased. PRA expression was augmented in the cervix and endometrium and unchanged in the vagina. Taken together, our results indicate that hormonal responses and receptor expression are differentially regulated in vaginal tissue compared with the cervix and endometrium.

Abstract 1315: DNMT and HDAC inhibitors resensitize resistant tumors to antiprogestin therapy in a mouse breast cancer model

Abstract Mouse mammary carcinomas induced by medroxyprogesterone acetate (MPA) are maintained by syngeneic transplantation and tumor variants with different hormone responsiveness have been generated. Tumors which grow without the MPA supply were defined as hormone independent (HI). Most of these tumors regress after antiprogestin (mifepristone, MIF) administration, while others show constitutive resistance to hormone therapy. We have previously demonstrated that responsive tumors show higher levels of progesterone receptor A (PRA) than PRB, while the opposite occurs in resistant tumors, indicating that the PR isoform ratio might be a predictor of antiprogestin responsiveness. We have also demonstrated that in constitutive resistant tumors PRA is silenced by methylation of its promoter, and that treatment with 5azadC (demethylating agent) induces PRA expression and tumors partially recover antiprogestin responsiveness. The aim of this study was to investigate whether the co-treatment with DNA methyltransferase (DNMT) and histone deacetylase (HDAC) inhibitors would enhance even more the responsiveness to MIF. For this purpose we investigated the expression of HDAC1 in constitutive resistant tumors and whether treatment of these tumors with 5azadC and trichostatin A (TSA; HDAC inhibitor) restored MIF responsiveness better than 5azadC alone. The constitutive resistant tumor 59-HI showed a higher expression of HDAC1 as compared to the antiprogestin sensititive tumor 59-2-HI as determined by Western blot (p&amp;lt;0,001) and immunohistochemistry, suggesting that these tumors might be candidates to respond to an HDAC inhibitor. 59-HI tumors were implanted sc in BALB/c mice and when tumors were palpable they were treated with a) 5azadC (1 mg/kg/every other day; ip), b) MIF (12 mg/kg/daily; sc), c) 5azadC plus MIF or d) TSA (1 mg/kg/every other day; sc), e) TSA plus 5azadC, f) TSA, 5azadC and MIF, or g) vehicle. Interestingly the co-treatment of 5azadC, TSA and MIF induced a significant inhibitory effect that was even greater than the one induced by 5azadC plus MIF (p&amp;lt;0.001). No inhibitory effects were observed when each compound was used alone or with TSA and MIF. The expression of PR was evaluated in control, 5azadC- and TSA plus 5azadC- treated tumors. An increase in PRA expression was observed by western blot and immunohistochemistry. The increase of PRA was higher with TSA plus 5azadC than with 5azadC alone (p&amp;lt;0,001). In conclusion, we report for the first time that a) constitutive resistant mammary carcinomas show high levels of HDAC1 which might be responsible for histone acetylation within the methylated PRA promoter, b) the combined treatment of demethylating agents and HDAC inhibitors increases the efficiency in both, PR re-expression and antiprogestin sensitivity. These results support our hypothesis that tumors with high levels of PRA are those which respond to antiprogestin treatment. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1315. doi:10.1158/1538-7445.AM2011-1315

Estrogen and progesterone receptor isoform distribution through the menstrual cycle in uteri with and without adenomyosis

To test the hypothesis that the expression of the different isoforms of the estrogen receptor alpha (ER-α) and beta (ER-β) and the progesterone receptor A (PR-A) and B (PR-B) would be differentially modulated in uteri with adenomyosis compared with controls and that modulation would be related to the menstrual cycle. Case control, blinded comparison. University department. 54 premenopausal women with and 35 without uterine adenomyosis as the sole pathology. Multiple samples studied using immunohistochemistry for estrogen and progesterone receptors. Histomorphometric analysis of receptor expression. The ER-α expression in the adenomyotic endometrium was different from that of the normal endometrium and the foci in the midsecretory phase of the cycle, but expression of ER-α in the inner and outer myometrium was not statistically significantly different. The ER-β expression was statistically significantly elevated in the adenomyotic functionalis gland during the proliferative phase and throughout the myometrium across the entire menstrual cycle. Expression of PR-A was similar to that of PR-B, with reduced expression in the basalis stroma, and inner and outer myometrium in the adenomyotic samples. The pattern of ER-β, PR-A, and PR-B expression was similar in the endometrial basalis and adenomyotic foci. These data suggest ER-β expression and the lack of PR expression are related to the development and/or progression of adenomyosis and might explain the poor response of adenomyosis-associated menstrual symptoms to progestational agents.

Immunohistochemical studies on uterine carcinosarcoma, leiomyosarcoma, and endometrial stromal sarcoma: expression and prognostic importance of ten different markers

Uterine sarcomas are rare and aggressive gynecologic malignancies. In this immunohistochemical (IHC) study, expression of Ki-67, p53, CD10, CD44, desmin, smooth muscle actin, estrogen receptor α (ERα), androgen receptor (AR), progesterone receptor A (PRA), and c-kit and their influence on survival in cases of uterine carcinosarcoma (CS), leiomyosarcoma (LMS), and endometrial stromal sarcoma (ESS) were evaluated. Medical records were reviewed and data collected concerning all uterine sarcomas treated during a 12-year period at Helsinki University Central Hospital. There was sufficient histological material for IHC analysis and slide review in 67 cases. Survival analysis was performed using the Kaplan-Meier method, and median survival times with 95% confidence intervals are given. Survival in cases of LMS was statistically significantly affected by the expression of p53, ERα, and PRA. Striking differences in expression of IHC markers when comparing results with those in earlier studies were the absence of AR immunoreactivity in all uterine sarcomas and low incidence of c-kit (15%; in endometrial stromal sarcoma). None of the markers was statistically significantly associated with survival of ESS and CS patients. The expression of p53, ERα, and PRA in uterine LMS may give prognostic information concerning the behavior of the disease. Hormonal therapy could be recommended as a treatment option in cases of hormone receptor-positive LMS.

BRCA1 selectively regulates the expression of progesterone receptor A in sporadic invasive ductal breast carcinoma

To investigate the expression level of BRCA1, progesterone receptor A (PRA) and B (PRB) in tissue of sporadic invasive ductal breast carcinoma and further statistically analyze the BRCA1 effects on the expression rates of PRA and PRB. Sixty-eight cases of adenosis of breast and sporadic invasive ductal breast carcinoma were selected. The corresponding paraffin-embodied tissues were collected from the archive of Department of Pathology, Nanfang Hospital. The expressions level of BRCA1, PRA and PRB were detected by immunohistochemistry. Wilcoxon two-sample test was used to analyze the differential expression of BRCA1 between adenosis and sporadic invasive ductal breast carcinoma. Chi-square test was used to analyze the effects of BRCA1 on the PRA or PRB expression rate. P value < 0.05 was considered statistically significant. (1) In invasive sporadic ductal breast carcinoma, the positive rate of BRCA1 expression of 60.29% (41/68) was lower than the positive rate of BRCA1 expression at 85.30% (58/68) in adenosis of breast. And the difference of BRCA1 expression between two groups was statistically significant (P < 0.01); (2) In invasive sporadic ductal breast carcinoma, the positive rate of PRA expression for negative BRCA1 expression samples was 81.48% (22/27) and it was higher than the positive rate of PRA expression at 53.66% (22/47) for positive BRCA1 expression samples. And the difference of PRA expression rates between two groups was statistically significant (P < 0.05). It indicated that the expression of BRCA1 affected the expression rate of PRA; In invasive sporadic ductal breast carcinoma, the PRB expression rates between positive and negative BRCA1 expression samples were not statistically significant (P > 0.05). It indicated that BRCA1 had no effect upon the expression rate of PRB. In sporadic breast carcinoma, a negative expression of BRCA1 is selectively associated with a higher expression rate of PRA rather than PRB. Thus BRCA1 selectively regulates the expression of PRA in sporadic breast carcinoma.

Effects of Progesterone and Its Antagonist Mifepristone on Progesterone Receptor A Expression in Human Umbilical Vein Endothelial Cells

Effects of female steroid hormones on endothelial cells are gaining increased importance due to several studies on the effects of hormonal treatment on cardiovascular risk. Recent data argue for an improvement of endothelium-derived relaxation and impaired vascular contraction by estradiol, whereas progesterone and testosterone might entail contrary effects. So far, gestagenic influence on endothelial cell physiology is poorly understood. Human umbilical vein endothelial cells (HUVECs) exposed to the female sex hormones estradiol and progesterone show expression of estrogen receptor-β (ERβ) and progesterone receptor A (PR-A), and are negative for ERα and PR-B. The aim of this study was to analyze the expression and stimulation of PR-A and -B in HUVECs after stimulation with progesterone and PR antagonists that are commercially available. PR-B expression or upregulation was abrogated after application of progesterone or antagonists to HUVECs. Expression of PR-A could be significantly upregulated with progesterone and mifepristone. Unexpectedly, stimulation with the progesterone antagonist RU486 (mifepristone) was accomplished by an upregulation of PR-A expression in our study. We conclude that gestagenic effects on HUVECs independent of modulators are mediated via the PR-A.

Human umbilical vascular endothelial cells express estrogen receptor beta (ERβ) and progesterone receptor A (PR-A), but not ERα and PR-B

Several reports deal with possible effects of female sex hormones on human umbilical vein endothelial cells (HUVEC) including elasticity, activation of plasma membrane Na+/H+ exchange, VEGF receptor Flk-1/KDR and many others. In contrast to those findings, some publications pointed out that HUVEC lack expression of both the estrogen receptor (ER) and/or the progesterone receptor (PR). Because the majority of these investigations were carried out at a time period, when only one ER and one PR was known, the aim of this study was the systematic analysis of ERalpha and ERbeta as well as PR-A and PR-B expression in HUVEC with specific monoclonal antibodies by immunocytochemistry and quantitative RT-PCR (TaqMan). As a result, we could show that HUVEC lack ERalpha but express ERbeta. The expression of ERbeta could be significantly upregulated with 17beta-estradiol on mRNA and protein level. In addition, HUVEC express PR-A but not PR-B. PR-A expression could be significantly upregulated with progesterone, again on mRNA and protein level. We conclude that estrogenic effects on HUVEC are mediated via the ERbeta and gestagens act via the PR-A pathway.