Progesterone-regulated Genes Research Articles

High concentrations of progesterone inhibit the expression of genes related to steroid metabolism in MA-10 Leydig cells

Leydig cells are the main testosterone-producing cells in males. During androgen synthesis, cholesterol enters the mitochondria via the STAR protein and is converted into pregnenolone by the CYP11A1 enzyme. This steroid is then exported from the mitochondria to be metabolized to progesterone by the HSD3B1 enzyme in the endoplasmic reticulum. In this study, we used 3′Tag-RNA-Seq to identify progesterone-regulated genes in MA-10 Leydig cells. Our results indicate that high concentrations of progesterone (30 μM) are involved in a negative feedback loop that inhibits cAMP/PKA-dependent activation of Star and Cyp11a1 expression and participate in cAMP/PKA-dependent down-regulation of genes related to the metabolism of steroid hormones. Linked to activation of the MAPK signaling pathway, endoplasmic reticulum stress and apoptosis, most of the genes encoding bZIP transcription factors are upregulated by progesterone in MA-10 Leydig cells. However, only DDIT3 protein levels are increased in response to progesterone in MA-10 Leydig cells. Like normal Leydig cells, MA-10 cells very weakly express the classical nuclear receptor for progesterone, suggesting that gene regulation by progesterone is rather mediated by one of the non-classical membrane receptors for progesterone However, current findings suggest that the inhibitory effect of progesterone on STAR protein increase in response to forskolin is not dependent on PGRMC1/2 or PAQR9. Furthermore, the increase in progesterone synthesis in response to activation of the cAMP/PKA pathway is rather inhibited by siRNA-mediated knockdown of PAQR9. Overall, this study shows that progesterone produced by Leydig cells participates in the regulation of steroidogenesis through autocrine action involving negative feedback upon activation of the cAMP/PKA pathway.

Chromatin architectural factor CTCF is essential for progesterone-dependent uterine maturation.

Receptors for estrogen and progesterone frequently interact, via Cohesin/CTCF loop extrusion, at enhancers distal from regulated genes. Loss-of-function CTCF mutation in >20% of human endometrial tumors indicates its importance in uterine homeostasis. To better understand how CTCF-mediated enhancer-gene interactions impact endometrial development and function, the Ctcf gene was selectively deleted in female reproductive tissues of mice. Prepubertal Ctcfd/d uterine tissue exhibited a marked reduction in the number of uterine glands compared to those without Ctcf deletion (Ctcff/f mice). Post-pubertal Ctcfd/d uteri were hypoplastic with significant reduction in both the amount of the endometrial stroma and number of glands. Transcriptional profiling revealed increased expression of stem cell molecules Lif, EOMES, and Lgr5, and enhanced inflammation pathways following Ctcf deletion. Analysis of the response of the uterus to steroid hormone stimulation showed that CTCF deletion affects a subset of progesterone-responsive genes. This finding indicates (1) Progesterone-mediated signaling remains functional following Ctcf deletion and (2) certain progesterone-regulated genes are sensitive to Ctcf deletion, suggesting they depend on gene-enhancer interactions that require CTCF. The progesterone-responsive genes altered by CTCF ablation included Ihh, Fst, and Errfi1. CTCF-dependent progesterone-responsive uterine genes enhance critical processes including anti-tumorigenesis, which is relevant to the known effectiveness of progesterone in inhibiting progression of early-stage endometrial tumors. Overall, our findings reveal that uterine Ctcf plays a key role in progesterone-dependent expression of uterine genes underlying optimal post-pubertal uterine development.

Abstract PS18-10: Intratumoural heterogeneity in PgR expression: Molecular and prognostic significance

Abstract Background: PgR is only expressed significantly in ER+ breast cancers and is generally considered a classical estrogen-sensitive protein, however, while ER+ cells are almost always expressed in a non-clustered pattern across the tumour bed, PgR+ cells form clusters or clumps with surrounding areas of PgR- cells when assessed by IHC in about 20-25% of PgR+ tumours. This is an ill-described and unexplained feature of intratumoural heterogeneity of a widely measured biomarker. The prognostic significance of the PgR clumpiness is also unknown. Aims: to determine the (i) biologic and (ii) prognostic significance of PgR clumpiness in ER+ primary breast cancer. Methods: (i) Biologic study: 40 primary ER+PgR+ tumours were identified with distinct PgR clumpiness by IHC. Areas of PgR+ and PgR- cells (PgR-rich and PgR-poor areas, respectively) were needle microdissected from unstained sections by juxtaposing them with PgR-stained sections from the same tumour. Areas were also dissected from 8 homogeneous PgR+ and 8 PgR- tumours for reference. NanoString gene expression analysis using a 50-gene code set (45 oestrogen-responsive or proliferation genes + 5 housekeeping genes) was performed on RNA extracts from the samples. (ii) Prognostic study: we developed a PgR heterogeneity score (PgR Het-score, range 0-18) as the product of (A) the number of PgR+ clumps/cm2 of tumour area (range 0 to 6) and (B) the level of overall PgR-positivity (0-4% or 96-100%, score 0; 5-19% or 80-95%, score 1; 20-39 or 60-79%, score 2; 40-59%, score 3). PgR Het-scores were derived from images (Hamamatsu NanoZoomer-XR) of PgR-stained sections from two sets of tumour biopsies taken at diagnosis after which all patients received adjuvant endocrine therapy: 322 tumours from the Royal Marsden and from Southern Sweden collected for a case:control study of risk of recurrence (recurrence:no recurrence, 1:1) and 591 patients from the TransATAC cohort study with time to recurrence as the end-point. Results: (i) Biologic study: In unsupervised hierarchical clustering of RNA expression from all samples, 33/40 pairs of PgR-rich and PgR-poor areas from a single tumour paired together and all 8 positive and negative control samples were grouped separately. Eight genes were differentially expressed between the PgR-rich and -poor areas (FDR<0.05: PGR, SERPINA3, AURKA, MSMB, PDZK1, IGSF1, FKBP5, SLC2A3). PGR had a 35-fold difference indicating that transcriptional differences explained the PgR IHC differences. The progesterone-regulated genes FKBP3 and SERPINA3 both showed significantly higher expression in PgR-rich areas consistent with the PgR differences having functional impact. AURKA was also more highly expressed in the PgR-rich areas indicating that the PgR-rich areas may also be more proliferative. ER and most of known estrogen-regulated genes were not differentially expressed and therefore show an unexpected divergence from PgR expression and regulation downstream of ER. (ii) Prognostic study: The PgR Het-score showed no consistent association with clinical factors including tumour size, nodal status, grade, age. Each of the individual components as well as the composite PgR Het score were significantly associated with risk of recurrence in POLAR: (A) p=0.02; (B) p=0.002; (PgR Het score) p=0.008. However, there was no association of the PgR Het score with risk of recurrence in TransATAC. Conclusion: Major, functionally significant differences in PgR expression occur within some ER+ tumours that are not explained by differences in ER expression and are not associated with differences in expression of most other estrogen-dependent genes. Further work is on-going to provide a mechanistic explanation for the PgR heterogeneity. Given the discordance in results from the two clinical studies its prognostic significance is uncertain. This work was funded by BCRF. Citation Format: Lila Zabaglo, Richard Buus, Eugene Schuster, Belinda Yeo, Marie Klintman, Ivana Sestak, Jack Cuzick, Ian Smith, Mitch Dowsett. Intratumoural heterogeneity in PgR expression: Molecular and prognostic significance [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS18-10.

Uterine Patterning, Endometrial Gland Development, and Implantation Failure in Mice Exposed Neonatally to Genistein.

Background:Embryo implantation relies on precise hormonal regulation, associated gene expression changes, and appropriate female reproductive tract tissue architecture. Female mice exposed neonatally to the phytoestrogen genistein (GEN) at doses similar to those in infants consuming soy-based infant formulas are infertile due in part to uterine implantation defects.Objectives:Our goal was to determine the mechanisms by which neonatal GEN exposure causes implantation defects.Methods:Female mice were exposed to GEN on postnatal days (PND)1–5 and uterine tissues collected on PND5, PND22–26, and during pregnancy. Analysis of tissue weights, morphology, and gene expression was performed using standard histology, confocal imaging with three-dimensional analysis, real-time reverse transcription polymerase chain reaction (real-time RT-PCR), and microarrays. The response of ovariectomized adults to (E2) and artificial decidualization were measured. Leukemia inhibitory factor (LIF) injections were given intraperitoneally and implantation sites visualized. Gene expression patterns were compared with curated data sets to identify upstream regulators.Results:GEN-exposed mice exhibited reduced uterine weight gain in response to E2 treatment or artificial decidualization compared with controls; however, expression of select hormone responsive genes remained similar between the two groups. Uteri from pregnant GEN-exposed mice were posteriorized and had reduced glandular epithelium. Implantation failure was not rescued by LIF administration. Microarray analysis of GEN-exposed uteri during early pregnancy revealed significant overlap with several conditional uterine knockout mouse models, including Foxa2, Wnt4, and Sox17. These models exhibit reduced endometrial glands, features of posteriorization and implantation failure. Expression of Foxa2, Wnt4, and Sox17, as well as genes important for neonatal uterine differentiation (Wnt7a, Hoxa10, and Msx2), were severely disrupted on PND5 in GEN-exposed mice.Discussion:Our findings suggest that neonatal GEN exposure in mice disrupts expression of genes important for uterine development, causing posteriorization and diminished gland function during pregnancy that contribute to implantation failure. These findings could have implications for women who consumed soy-based formulas as infants. https://doi.org/10.1289/EHP6336

Menstrual cycle associated changes in hormone-related gene expression in oestrogen receptor positive breast cancer

The major changes in hormone levels that occur through the menstrual cycle have been postulated to affect the expression of hormone-regulated and proliferation-associated genes (PAGs) in premenopausal ER+ breast cancer. Whilst previous studies have demonstrated differences in gene expression, here, we investigated if there are within patient changes in the expression of oestrogen- and progesterone-regulated genes (ERGs and PRGs) and PAGs in ER+ breast cancer during the menstrual cycle. Samples from 96 patients in two independent prospective studies of the effect of menstrual cycle on ER+ breast cancer were used. Plasma hormone measurements were used to assign tumours to one of three pre-defined menstrual cycle windows: W1 (days 27–35 and 1–6; low oestradiol and low progesterone), W2 (days 7–16; high oestradiol and low progesterone) and W3 (days 17–26; intermediate oestradiol and high progesterone). RNA expression of 50 genes, including 27 ERGs, 11 putative PRGs and seven PAGs was measured. The AvERG (geomean of PGR, GREB1, TFF1 and PDZK1) was used as a composite measure of ERG expression and showed significant changes between the three windows of the menstrual cycle increasing over 2.2-fold between W1 and W2 and decreasing between W2 and W3 and between W3 and W1. Proliferation gene expression also varied significantly, following the same pattern of changes as ERG expression, but the changes were of lower magnitude (1.4-fold increase between W1 and W2). Significant changes in the expression of eight individual ERGs, including GREB1, PGR and TFF1, and two PAGs were observed between W1 and either W2 or W3 with all genes showing higher levels in W2 or W3 (1.3–2.4-fold; FDR 0.016–0.05). The AvProg, a composite measure of PRG expression, increased significantly (1.5-fold) in W3 compared to W1 or W2 but no significant changes were observed for individual PRGs. In conclusion, we observed significant changes in ERG, PRG and PAG expression in ER+ breast tumours during the menstrual cycle that may affect the assessment and interpretation of prominent biomarkers (e.g. PgR) and commonly used multigene prognostic signatures in premenopausal ER+ breast cancer.

Myometrial progesterone hyper-responsiveness associated with increased risk of human uterine fibroids

BackgroundUterine Fibroids (UFs) growth is ovarian steroid-dependent. Previous studies have shown that estrogen and progesterone play an important role in UF development. However, the mechanism underlying progesterone induced UF pathogenesis is largely unknown. In this study, we determined the expression of progesterone receptor and compared the expression level of progesterone-regulated genes (PRGs) in human myometrial cells from normal uteri (MyoN) versus uteri with UFs (MyoF) in response to progesterone.MethodsPrimary human myometrial cells were isolated from premenopausal patients with structurally normal uteri (PrMyoN). Primary human myometrial cells were also isolated from uterus with UFs (PrMyoF). Isolated tissues were excised at least 2 cm from the closest UFs lesion(s). Progesterone receptor (PR) expression was assessed using Western blot (WB). Expression levels of 15 PRGs were measured by qRT-PCR in PrMyoN and PrMyoF cells in the presence or absence of progesterone.ResultsWB analysis revealed higher expression levels of PR in PrMyoF cells as compared to PrMyoN cells. Furthermore, we compared the expression patterns of 15 UF-related PRGs in PrMyoN and PrMyoF primary cells in response to progesterone hormone treatment. Our studies demonstrated that five PRGs including Bcl2, FOXO1A, SCGB2A2, CYP26a1 and MMP11 exhibited significant progesterone-hyper-responsiveness in human PrMyoF cells as compared to PrMyoN cells (P < 0.05). Another seven PRGs, including CIDEC, CANP6, ADHL5, ALDHA1, MT1E, KIK6, HHI showed gain in repression in response to progesterone treatment (P > 0.05). Importantly, these genes play crucial roles in cell proliferation, apoptosis, cell cycle, tissue remodeling and tumorigenesis in the development of UFs.ConclusionThese data support the idea that progesterone acts as contributing mechanism in the origin of UFs. Identification and analysis of these PRGs will help to further understand the role of progesterone in UF development.

The involvement of the progesterone receptor in PIBF and Gal-1 expression in the mouse endometrium.

The progesterone-regulated genes, PIBF and Gal-1, are key players in the feto-maternal immunological interaction. This study aims to investigate the expression of PIBF and Gal-1 in WT and progesterone receptor KO models as well as subsequent effects of PIBF on decidualization of stromal cells. PRAKO, PRBKO and PRKO BALB/c mice were used for assessing the role of PR isoforms in PIBF induction. PIBF- and Gal-1 mRNA expression in the uterus was tested by real-time PCR. The effect of PIBF on decidualization of endometrial stromal cells was verified by anti-desmin immunofluorescence. Immunohistochemistry was used for testing PIBF expression in the uterus. Gal-1, ERα and PR positive decidual NK cells were detected by immunofluorescence. PIBF mRNA was significantly increased in progesterone-treated WT mice, but not in PRKO and PRAKO mice. PIBF protein expression was reduced in the endometria of PRKO and PRAKO, but not in PRBKO mice. During a 6-day culture, PIBF induced decidual transformation of endometrial stromal cells. PIBF expression in the mouse uterus was highest during the implantation window, while Gal-1 mRNA expression continuously increased between day 2.5 and day 11.5 of gestation. Decidual NK cells express Gal-1 and ERα, but not PR at day 7.5 murine pregnancy. PIBF produced via engagement of PRA, is highly expressed in the endometrium during the implantation window, and plays a role in decidualization. The concerted action of PIBF and Gal-1 might contribute to the low cytotoxic activity of decidual NK cells.

Effects of serum estradiol and progesterone on estrogen-regulated gene expression in breast cancers of premenopausal patients.

Expression of estrogen receptor α in breast cancer is essential for estrogen-dependent growth and partially determines the breast cancer subtype. In premenopausal women, expression of estrogen-regulated genes in estrogen receptor-positive breast cancer tissues are reportedly influenced by the menstrual cycle. We investigated correlations between serum estradiol (E2; tested on the day of surgery) and expression of estrogen-regulated genes and proliferation genes in strongly estrogen receptor α-positive breast cancer tissues from 91 premenopausal women by quantitative reverse transcription-polymerase chain reaction. We also investigated correlations between serum progesterone levels on the day of surgery and mRNA expression of progesterone-regulated genes and proliferation genes. The serum E2 level affected expression of estrogen-regulated genes, including progesterone receptor (P = 0.016, Rs = 0.07) but showed no correlation with expression of genes associated with proliferation. We also observed strong positive correlations between mRNA expression of ESR1 and that of estrogen-regulated genes (P < 0.0001, Rs = 0.329-0.756) and proliferation genes (P < 0.0001, Rs = 0.753-0.843). The serum progesterone level affected expression of RANKL mRNA. However, we observed no correlations between serum progesterone and expression of Wnt-4 or proliferation genes. The serum E2 level on the day of surgery influences estrogen-regulated gene expression moderately in patients found to be strongly positive for estrogen receptor α by immunohistochemistry. Changes in serum E2 levels might influence the results of molecular profiling tests in premenopausal women with breast cancer.

Endometrial transcript profile of progesterone-regulated genes during early pregnancy of Water Buffalo (Bubalus bubalis).

Progesterone (P4 ) plays a key role in the establishment and maintenance of pregnancy in most mammals. Unravelling the expression of progesterone-regulated genes can expand the understanding of the embryonic mortality. Accordingly, we studied the relative mRNA expression of the P4 -regulated genes in the buffalo. Uteri were collected from the abattoir and categorized into nonpregnant late luteal phase, stage I (28-38th days of gestation) and stage II (48-56th days of gestation) of pregnancy (n=6/group). After extraction of total RNA from the endometrial tissues, we carried out qRT-PCR for determining the relative mRNA expression of the P4 -regulated genes using nonpregnant late luteal phase as calibrator group. The expression of LGALS3BP (essential for maternal recognition of pregnancy) gene was found to be significantly upregulated (p<0.05), while MUC1 (important for embryo attachment) gene was downregulated in stage I and II of pregnancy. We observed no significant change in the expression of LGALS1, LGALS9 and CTSL genes. The SLC5A11 and SLC2A1 genes (involved in the transport of glucose to endometrium) in early pregnancy were upregulated in the pregnancy stage I (p<0.05) relative to nonpregnant late luteal phase. The CST3 gene was significantly upregulated in pregnancy stage II (p<0.01). These results provide molecular insights into the specific pathways involved in foeto-maternal communication during early pregnancy in buffaloes.

Molecular changes in premenopausal oestrogen receptor-positive primary breast cancer in Vietnamese women after oophorectomy

For premenopausal women with primary ER + breast cancer, oophorectomy (OvX) is an evidence-based cost-effective option and is standard treatment in many countries. However, there is virtually no data describing the effects of OvX on breast tumour biology. We therefore, characterised the endocrine and genome-wide transcriptional impact of OvX in 56 premenopausal women with ER + breast cancer for 2 weeks prior to mastectomy. Plasma estradiol concentrations decreased from 406 ± 41 to 20.7 ± 2.6 pmol/l (mean ± sem) 24 h after OvX, and to 8.1 ± 0.8 pmol/l 2 weeks later at mastectomy. Ki67 decreased in 33/36 (91.7%) tumours. The expression of 655 genes changed significantly (FDR < 1%) with an absolute mean fold-change (FC) ≥ 1.25 (257 up, 398 down). Archetypal oestrogen-regulated genes (TFF1, GREB1, PGR and PDZK1) showed large decreases in expression (FC = 0.20–0.69; p < 1e-6-1e-7). Proliferation-associated genes (e.g. TOP2A, AURKA and UBE2C) were also strongly downregulated (FC = 0.38–0.56; p < 1e-7) along with putative progesterone-regulated genes (e.g. FKBP4, MYB; FC = 0.64–0.68; p < 1e-4-1e-7). The gene expression changes did not differ according to HER2 status and correlated strongly with the changes reported previously after aromatase inhibitor (AI) treatment in postmenopausal women (rho = 0.55, p < 1e-04). However, after OvX the mean FC was significantly higher compared to AI (p < 1e-04). In conclusion, changes in tumoural gene expression after OvX were largely similar, but of a greater magnitude to those observed after AI in postmenopausal patients; however, OvX appeared to have a greater effect on progesterone-regulated genes than AI.

A Role for Progesterone-Regulated sFRP4 Expression in Uterine Leiomyomas.

Context:Despite progesterone’s key role in uterine smooth muscle tumorigenesis, the mechanisms by which it promotes the growth of uterine leiomyomas remain poorly understood.Objective:The aim of this study was to identify gene products mediating the effects of progesterone in uterine leiomyomas.Design:Gene expression profiling was used to identify putative progesterone-regulated genes differentially expressed in uterine leiomyomas, which were then studied in vitro.Methods:Gene expression was comprehensively profiled with the Illumina WG BeadChip (version 2.6) and analyzed with a bioinformatic algorithm that integrates known protein–protein interactions. Genomic binding sites for progesterone receptor (PR) were interrogated by chromatin immunoprecipitation—quantitative polymerase chain reaction (ChIP-qPCR). Small interfering RNA was used to study gene function in primary cell lines.Results:Our analyses identified secreted Frizzled-related protein 4 (sFRP4) as a key gene product functionally linked to PR activation whose expression was 2.6 times higher in leiomyomas than myometrium (n = 26, P < 0.01) and 2.5 times higher during the proliferative phase of the menstrual cycle (n = 26, P < 0.01). Direct binding between PR and sFRP4 promoter was observed by ChIP-qPCR. Robust overexpression of sFRP4 was also observed in primary cultures derived from leiomyoma. Progesterone preferentially inhibited sFRP4 expression and secretion in leiomyoma cultures in a dose-dependent manner sensitized by estradiol. Knockdown of sFRP4 inhibited proliferation and apoptosis in primary cultures of both myometrium and leiomyoma.Conclusions:Overexpression of sFRP4 is a robust, progesterone-regulated feature of leiomyomas that increases smooth muscle proliferation. More work is needed to elucidate how progesterone’s ability to modulate sFRP4 expression contributes to uterine smooth muscle tumorigenesis.

Selective progesterone receptor modulator (SPRM) ulipristal acetate (UPA) and its effects on the human endometrium.

STUDY QUESTIONWhat is the impact of administration of the selective progesterone receptor modulator (SPRM), ulipristal acetate (UPA) on the endometrium of women with fibroids?SUMMARY ANSWERUPA administration altered expression of sex-steroid receptors and progesterone-regulated genes and was associated with low levels of glandular and stromal cell proliferation.WHAT IS KNOWN ALREADYAdministration of all SPRM class members results in PAEC (progesterone receptor modulator associated endometrial changes). Data on the impact of the SPRM UPA administration on endometrial sex-steroid receptor expression, progesterone (P)-regulated genes and cell proliferation are currently lacking.STUDY DESIGN SIZE, DURATIONObservational study with histological and molecular analyses to delineate impact of treatment with UPA on endometrium. Endometrial samples (n = 9) were collected at hysterectomy from women aged 39 to 49 with uterine fibroids treated with UPA (oral 5 mg daily) for 9–12 weeks. Control proliferative (n = 9) and secretory (n = 9) endometrium from women aged 38–52 with fibroids were derived from institutional tissue archives.PARTICIPANTS/MATERIALS, SETTING, METHODSStudy setting was a University Research Institute. Endometrial biopsies were collected with institutional ethical approval and written informed consent. Concentrations of mRNAs encoded by steroid receptors, P-regulated genes and factors in decidualised endometrium were quantified with qRT-PCR. Immunohistochemistry was employed for localization of progesterone (PR, PRB), androgen (AR), estrogen (ERα) receptors and expression of FOXO1, HAND2, HOXA10, PTEN homologue. Endometrial glandular and stromal cell proliferation was objectively quantified using Ki67.MAIN RESULTS AND THE ROLE OF CHANCEUPA induced morphological changes in endometrial tissue consistent with PAEC. A striking change in expression patterns of PR and AR was detected compared with either proliferative or secretory phase samples. There were significant changes in pattern of expression of mRNAs encoded by IGFBP-1, FOXO1, IL-15, HAND2, IHH and HOXA10 compared with secretory phase samples consistent with low agonist activity in endometrium. Expression of mRNA encoded by FOXM1, a transcription factor implicated in cell cycle progression, was low in UPA-treated samples. Cell proliferation (Ki67 positive nuclei) was lower in samples from women treated with UPA compared with those in the proliferative phase.LARGE SCALE DATAN/A.LIMITATIONS REASONS FOR CAUTIONA small number of well-characterized patients were studied in-depth. The impacts on morphology, molecular and cellular changes with SPRM, UPA administration on symptom control remains to be determined.WIDER IMPLICATIONS OF THE FINDINGSP plays a pivotal role in endometrial function. P-action is mediated through interaction with the PR. These data provide support for onward development of the SPRM class of compounds as effective long-term medical therapy for heavy menstrual bleeding.STUDY FUNDING/COMPETING INTEREST(S)H.O.D.C. received has clinical research support for laboratory consumables and staff from Bayer Pharma Ag and provides consultancy advice (no personal remuneration) for Bayer Pharma Ag, PregLem SA, Gedeon Richter, Vifor Pharma UK Ltd, AbbVie Inc.; A.R.W.W. has received consultancy payments from Bayer, Gedeon Richter, Preglem SA, HRA Pharma; L.H.R.W., A.A.M., R.M., G.S. and P.T.K.S. have no conflicts of interest. Study funded in part from each of: Medical Research Council (G1002033; G1100356/1; MR/N022556/1); National Health Institute for Health Research (12/206/520) and TENOVUS Scotland.

Myeloid decidual dendritic cells and immunoregulation of pregnancy: defective responsiveness to Coxiella burnetii and Brucella abortus

Dendritic cells (DCs) are a component of the placental immune system, but their role in pregnancy is still poorly understood. Decidual DCs (dDCs) were selected from at-term pregnancy on the basis of CD14 and CD11c expression. A phenotypic analysis revealed that dDCs are characterized by the expression of monocyte-derived DC (moDCs) markers and specific markers such as HLA-G and its ligand ILT4. As demonstrated by whole-genome microarray, dDCs expressed a specific gene program markedly distinct from that of moDCs; it included estrogen- and progesterone-regulated genes and genes encoding immunoregulatory cytokines, which is consistent with the context of foeto-maternal tolerance. A functional analysis of dDCs showed that they were unable to mature in response to bacterial ligands such as lipopolysaccharide or peptidoglycan, as assessed by the expression of HLA-DR, CD80, CD83, and CD86. When dDCs were incubated with bacteria known for their placenta tropism, Coxiella burnetii and Brucella abortus, they were also unable to mature and to produce inflammatory cytokines. It is likely that the defective maturation of dDCs and their inability to produce inflammatory cytokines is related to the spontaneous release of IL-10 by these cells. Taken together, these results suggest that dDCs exhibit an immunoregulatory program, which may favor the pathogenicity of C. burnetii or B. abortus.

Abstract P5-05-04: Relationship between plasma estradiol levels and estrogen-regulated gene expressions in premenopausal estrogen receptor-positive breast cancers

Abstract Background: Estrogen receptor (ER) and progesterone receptor (PgR) expression status in breast cancer are important factors in determining the use of adjuvant therapy. Plasma estradiol (E2) and progesterone vary markedly through the menstrual cycle. Recently, the levels of PgR expression were reported to be correlated with E2 at the time of surgery in Caucasian premenopausal breast cancer patients. Materials and methods: In this study, plasma E2 levels at surgery were examined for correlations with expressions of estrogen-regulated genes (ERGs), including PgR, and proliferation genes in 147 Japanese premenopausal ER-positive breast cancers. Plasma E2 and progesterone, FSH, and LH were measured on the day of surgery by ECLIA and mRNA expressions were analyzed for 4 ERGs (PgR, GREB1, TFF1, PDZK1), 2 progesterone-regulated (RANKL, cyclin D1) and 2 proliferation genes (MKI67, BIRC5) by RT-PCR using the TaqMan system. ER and PgR protein expression levels were estimated by immunohistochemistry. Results: Our results revealed that expressions of PgR mRNA and protein in breast cancer tissues were significantly correlated with plasma E2 levels at surgery (p = 0.005, p = 0.0165, respectively). Other ERGs were also significantly correlated with plasma E2 levels. However, there were no correlations between mRNA expressions of proliferation genes, MKI67 and BIRC5, and plasma E2 levels. Furthermore, mRNA expressions of the progesterone-regulated genes, RANKL and cyclin D1, were significantly correlated with PgR mRNA expression (p&amp;lt;0.0001, p&amp;lt;0.0001, respectively). Discussion: Significant correlations were seen in the expression of ERGs in Japanese ER-positive breast cancers according to the plasma E2 levels, which vary markedly through the menstrual cycle. Our results supported the previous report in Caucasian patients by other group. This variability may affect the interpretation of gene expression profiles incorporating ERGs such as the 21-gene recurrence score. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-05-04.

The human oviduct transcriptome reveals an anti-inflammatory, anti-angiogenic, secretory and matrix-stable environment during embryo transit

The human oviduct serves as a conduit for spermatozoa in the peri-ovulatory phase and nurtures and facilitates transport of the developing embryo for nidation during the luteal phase. Interactions between the embryo and oviductal epithelial surface proteins and secreted products during embryo transit are largely undefined. This study investigated gene expression in the human oviduct in the early luteal versus follicular phases to identify candidate genes and biomolecular processes that may participate in maturation and transport of the embryo as it traverses this tissue. Oviductal RNA was hybridized to oligonucleotide arrays and resulting data were analysed by bioinformatic approaches. There were 650 genes significantly down-regulated and 683 genes significantly up-regulated (P<0.05) in the luteal versus follicular phase. Quantitative real-time PCR, immunoblot analysis and immunohistochemistry confirmed selected gene expression and cellular protein localization. Down-regulated genes involved macrophage recruitment, immunomodulation and matrix-degeneration, and up-regulated genes involved anti-inflammatory, ion transport, anti-angiogenic and early pregnancy recognition. The oviduct displayed some similarities and differences in progesterone-regulated genes compared with the human endometrium. Together, these data suggest a unique hormonally regulated environment during embryo development, maturation and transport through human oviduct and some conservation of progesterone signalling in tissues of common embryological origin.The oviduct serves as a conduit for spermatozoa in the peri-ovulatory phase and it nurtures and facilitates transport of the developing embryo during the luteal phase of the menstrual cycle, although precise interactions between the embryo and oviductal epithelium and secreted products are largely undefined. Herein, we investigated gene expression in human oviduct to identify candidate genes and processes that may participate in maturation and transport of the embryo as it develops implantation competence. Total RNA from human ampullary oviducts in the early luteal versus follicular phases was isolated and hybridized to oligonucleotide arrays. The data, analysed by bioinformatic approaches, revealed that 650 genes were significantly down- and 683 genes were significantly up-regulated in the luteal phase. Quantitative real-time PCR, immunoblot analysis and immunohistochemistry confirmed selected gene expression and cellular protein localization. The data demonstrated down-regulation of genes involved in macrophage recruitment, immunomodulation and matrix degeneration and up-regulation of ion transport and secretions, as well as anti-angiogenic and early pregnancy recognition. Together, these data suggest a unique hormonally regulated environment during embryo development, maturation and transport through the human oviduct and provide insight into mechanisms influencing acquisition of implantation competence of the human embryo during its passage through the oviduct en route to the uterine endometrium.

Progesterone Resistance in PCOS Endometrium: A Microarray Analysis in Clomiphene Citrate-Treated and Artificial Menstrual Cycles

Polycystic ovary syndrome (PCOS), the most common endocrinopathy of reproductive-aged women, is characterized by ovulatory dysfunction and hyperandrogenism. The aim was to compare gene expression between endometrial samples of normal fertile controls and women with PCOS. We conducted a case control study at university teaching hospitals. Normal fertile controls and women with PCOS participated in the study. Endometrial samples were obtained from normal fertile controls and from women with PCOS, either induced to ovulate with clomiphene citrate or from a modeled secretory phase using daily administration of progesterone. Total RNA was isolated from samples and processed for array hybridization with Affymetrix HG U133 Plus 2 arrays. Data were analyzed using GeneSpring GX11 and Ingenuity Pathways Analysis. Selected gene expression differences were validated using RT-PCR and/or immunohistochemistry in separately obtained PCOS and normal endometrium. ANOVA analysis revealed 5160 significantly different genes among the three conditions. Of these, 466 were differentially regulated between fertile controls and PCOS. Progesterone-regulated genes, including mitogen-inducible gene 6 (MIG6), leukemia inhibitory factor (LIF), GRB2-associated binding protein 1 (GAB1), S100P, and claudin-4 were significantly lower in PCOS endometrium; whereas cell proliferation genes, such as Anillin and cyclin B1, were up-regulated. Differences in gene expression provide evidence of progesterone resistance in midsecretory PCOS endometrium, independent of clomiphene citrate and corresponding to the observed phenotypes of hyperplasia, cancer, and poor reproductive outcomes in this group of women.

Effect of Elevated Circulating Progesterone Concentration on Bovine Blastocyst Development and Global Transcriptome Following Endoscopic Transfer of In Vitro Produced Embryos to the Bovine Oviduct1

Elevated concentrations of circulating progesterone in the immediate postconception period have been associated with an increase in embryonic growth rate, interferon-tau production, and pregnancy rate in cattle and sheep. Much of this effect is likely mediated via downstream effects of progesterone-induced changes in gene expression in the uterine tissues. Using state-of-the-art endoscopic techniques, this study examined the effect of elevated progesterone on the development of in vitro produced bovine zygotes transferred to the oviducts of heifers with high or normal circulating progesterone concentrations and on the transcriptome of blastocysts developing under such conditions. Simmental heifers (n = 34) were synchronized using a controlled internal drug release (CIDR) device for 8 days, with a prostaglandin F(2 alpha) analogue administered 3 days before removal of the CIDR device. Only animals exhibiting a clear standing estrus (Day 0) were used. To produce animals with divergent progesterone concentrations, half of the animals received a progesterone-releasing intravaginal device (PRID) on Day 3 of the estrous cycle; the PRID was left in place until embryo recovery. All animals were sampled for blood daily from Day 0 to Day 7. Cleaved embryos were transferred by endoscopy to the ipsilateral oviduct of each recipient on Day 2 and then recovered by nonsurgically flushing the oviduct and the uterus on Day 7. The number of embryos developing to the blastocyst stage was recorded at recovery and following overnight culture in vitro. Potential effects of elevated progesterone on transcript abundance were examined using the Affymetrix GeneChip Bovine Genome Array. Insertion of a PRID on Day 3 resulted in a significant elevation of progesterone concentration (P < 0.05) from Day 3.5 until Day 6. Elevated progesterone did not affect the proportion of embryos developing to the blastocyst stage. Genomewide gene expression analysis identified 194 differentially expressed genes between embryos collected from heifers with normal or elevated progesterone, and quantitative real-time PCR validation with a subset of selected genes and an independent sample confirmed the microarray results. Interaction network analysis indicated a significant interaction between progesterone-regulated genes in the blastocyst and in the maternal endometrium. These results suggest that elevated concentrations of progesterone do not affect the ability of the early embryo to reach the blastocyst stage in vivo but do result in subtle changes to the transcriptome of the embryo that may be associated with advanced elongation posthatching.

Altered Gene Expression Profiling in Endometrium: Evidence for Progesterone Resistance

Progesterone plays an important role in regulating multiple events in the uterus. It controls endometrial proliferation and differentiation, which are important for uterine function. Dysregulation of progesterone signaling leads to impaired physiological functions. Indeed, aberrant expression of progesterone-regulated genes in the endometrium has been implicated in several gynecologic disorders, including endometriosis, polycystic ovarian syndrome (PCOS), and endometrial hyperplasia. Although several investigators have analyzed eutopic endometrial expression of progesterone-target genes, the genesis and consequences of progesterone resistance remain unclear. We review evidence for progesterone resistance in endometrium of women with endometriosis, PCOS, and endometrial hyperplasia, and we identify possible mechanisms associated with reduced progesterone activity in endometrium of (some) women with these gynecologic disorders that have a significant impact on women's health and well-being.

Progesterone Resistance in a Baboon Model of Endometriosis

The development of a baboon model of induced endometriosis, which recapitulates the retrograde menstruation hypothesis, has greatly facilitated our understanding of the early events associated with the disease process. Sequential analysis of the eutopic endometrium following the establishment of disease suggests that the development of progesterone resistance is a gradual process and becomes evident after 6 months of disease induction. This resistance is manifested by a decreased responsiveness of the progesterone receptor and its chaperone immunophilins as well as epigenetic modifications of progesterone-regulated genes. In comparative studies, the time-dependent changes observed in the baboon eutopic endometrium are similar to those that have been reported to be altered in women with endometriosis. The baboon model therefore provides insight into the potential mechanisms by which genes in the eutopic endometrium are dysregulated and how this alteration results in infertility that is associated with endometriosis.

Progesterone-Mediated Immunomodulation in Pregnancy: its Relevance to Leukocyte Immunotherapy of Recurrent Miscarriage

Progesterone is crucial for the establishment and maintenance of pregnancy. Progesterone-regulated genes in the pregnant uterus control the development of endometrial receptivity as well as recruitment and differentiation of decidual NK cells, which in turn act on angiogenesis and trophoblast invasion. The link between progesterone and the immune system is established by lymphocyte progesterone receptors expressed in peripheral blood gammadelta T cells of pregnant women and in peripheral NK cells. Regulation of lymphocyte progesterone receptors is activation related, thus efficient recognition of fetal antigens is a requirement for the initiation of progesterone-dependent immunoregulatory mechanisms. Several immunological effects of progesterone are mediated by progesterone-induced blocking factor--the product of a progesterone-induced gene in lymphocytes. One part of unexplained recurrent miscarriages might have an immunological etiology. Immunization of the mothers with paternal or third-party leukocytes aims to correct the misregulated antifetal immune response. There are, however, serious concerns about this treatment, including the lack of information about the mode of action and possible adverse effects of the treatment, the failure to detect a significant effect of immunotherapy and the lack of a reliable generally accepted marker for patient selection. These concerns will be discussed in this review.