Endometrial stromal beta-catenin is required for steroid-dependent mesenchymal-epithelial cross talk and decidualization
© Zhang et al.; licensee BioMed Central Ltd. 2012
Received: 16 April 2012
Accepted: 4 September 2012
Published: 7 September 2012
Beta-catenin is part of a protein complex associated with adherens junctions. When allowed to accumulate to sufficient levels in its dephosphorylated form, beta-catenin serves as a transcriptional co-activator associated with a number of signaling pathways, including steroid hormone signaling pathways.
To investigate the role of beta-catenin in progesterone (P4) signaling and female reproductive physiology, conditional ablation of Ctnnb1 from the endometrial mesenchymal (i.e. stromal and myometrial), but not epithelial, compartment was accomplished using the Amhr2-Cre mice. Experiments were conducted to assess the ability of mutant female mice to undergo pregnancy and pseudopregnancy by or through oil-induced decidualization. The ability of uteri from mutant female mice to respond to estrogen (E2) and P4 was also determined.
Conditional deletion of Ctnnb1 from the mesenchymal compartment of the uterus resulted in infertility stemming, in part, from complete failure of the uterus to decidualize. E2-stimulated epithelial cell mitosis and edematization were not altered in mutant uteri indicating that the mesenchyme is capable of responding to E2. However, exposure of ovariectomized mutant female mice to a combined E2 and P4 hormone regimen consistent with early pregnancy revealed that mesenchymal beta-catenin is essential for indirectly opposing E2-induced epithelial proliferation by P4 and in some mice resulted in development of endometrial metaplasia. Lastly, beta-catenin is also required for the induced expression of genes that are known to play a fundamental role in decidualization such as Ihh, Ptch1, Gli1 and Muc1
Three salient points derive from these studies. First, the findings demonstrate a mechanistic linkage between the P4 and beta-catenin signaling pathways. Second, they highlight an under appreciated role for the mesenchymal compartment in indirectly mediating P4 signaling to the epithelium, a process that intimately involves mesenchymal beta-catenin. Third, the technical feasibility of deleting genes in the mesenchymal compartment of the uterus in an effort to understand decidualization and post-natal interactions with the overlying epithelium has been demonstrated. It is concluded that beta-catenin plays an integral role in selective P4-directed epithelial-mesenchymal communication in both the estrous cycling and gravid uterus.
KeywordsBeta-catenin Decidualization Endometrium Implantation Pregnancy Progesterone Uterus
The stromal/mesenchymal compartment of the endometrium performs a variety of tasks important for uterine physiology, including relaying specific aspects of steroid hormone signaling to the overlying epithelium. An example of such mesenchymal-to-epithelial signaling occurs in response to estradiol (E2) binding to and activating estrogen receptor (ESR1), inducing the expression of stromal-derived growth factors that stimulate epithelial cell cycle progression, hypertrophy, and initiating secretory functions (reviewed in ). In invasively implanting species, the stroma also undergoes decidualization during early pregnancy following embryo apposition and attachment to the uterine luminal epithelium, a process inherently regulated by progesterone (P4) following E2 priming. Here, stromal cells terminally differentiate and contribute to pregnancy by performing placenta-like functions until such time that the embryo develops its own nutrient and gas exchange apparatus, the placenta . Stromal decidualization is regulated, in part, by cues derived from the epithelium such as Indian hedgehog.
It is thought that ESR1 mediates E2-initiated signaling in the uterus. However, it is generally understood that E2-initiated transcriptional and physiological changes occur in two phases . The first occurs within 2–6 hours, and the second takes place between 24–72 hours. Although many E2-initiated transcriptional events require binding of ESR1 to estrogen response elements (ERE), many other genes are regulated in an ER-dependent, but ERE-independent fashion . This suggests that ESR1 interacts with other transcriptional modulators that in turn interact with DNA to regulate gene expression at promoter sites distinct from EREs. Within the uterine epithelium, one such ESR1 interacting molecule is the transcriptional co-activator β-catenin [5, 6]. The late transcriptional response to E2 is thought to be mediated, in part, by the ESR1:β-catenin interaction. Equally complex signaling mechanisms likely coordinate P4 responses, but such pathways are less clearly understood.
β-catenin is best known for its central role in the canonical wingless-type MMTV integration site family member (Wnt) signaling pathways and β-catenin is essential for development, transcription, cell adhesion and tumorigenesis . In the absence of Wnt signaling, β-catenin is found in the cytoplasm either as a component that binds cadherins to α-catenin and the cytoskeleton at adherens junctions or in a complex with adenomatous polyposis coli (APC), axin, and glycogen synthase kinase 3β (GSK-3β), wherein it is phosphorylated and subject to ubiquitination and proteasomal degradation. Activation of frizzled receptors by Wnt ligands disrupts the APC complex and inhibits GSK-3β activity causing an accumulation of unphosphorylated (i.e., activated) β-catenin, which promotes its nuclear localization and subsequent regulation of target gene expression . β-catenin is therefore uniquely situated at a bottleneck in the Wnt signaling pathway.
Much of the focus of steroid hormone signaling studies in the uterus has been directed at the epithelial compartment. In the present study, the function of β-catenin in the stromal compartment was investigated in the contexts of steroid hormone action and stromal cell decidualization. Our findings reveal that conditional inactivation of β-catenin in endometrial stroma results in disrupted progesterone signaling and complete loss of stromal cell decidua-lization, indicating that steroid-dependent and β-catenin signaling pathways intersect to regulate postnatal uterine functions.
Animal protocols were approved by either the Massachusetts General Hospital or the Washington State University Institutional Care and Use Committee. For histology, mature (6–8 weeks old) ICR female mice were placed with intact ICR males of proven breeding capacity or with vasectomized ICR males. Female mice were considered day of pregnancy (DOP) or day of pseudopregnancy (DOPP) 0.5 upon observation of a vaginal seminal plug. Whole implantation sites (pregnancy) or mechanically decidualized uterine tissue (pseudopregnancy) were collected on days 4.5, 6.5 and 7.5 and prepared for RNA isolation or paraffin sectioning as described below. Decidualization was induced in pseudopregnant female mice by infusing 10 μl of sesame oil into the uterine lumen on DOPP 4.
The utility of the anti-Müllerian hormone type II receptor (Amhr2) promoter to drive Cre recombinase expression in mice during uterine decidualization was first established by crossing Amhr2 Cre transgenic mice (Amhr2tm3(cre)Bhr/+), kindly provided by Dr. Richard Behringer or purchased from the Mutant Mouse Regional Resource Center, with Rosa-EYFP reporter mice containing a yellow fluorescent protein gene downstream of a loxP-flanked stop sequence (Gt(ROSA)26Sor tm1(EYFP)Cos ) . To study β-catenin function in endometrial stromal tissue Amhr2 Cre mice were mated with mice harboring a Ctnnb1 gene with exons 2–6 flanked by loxP sites (Ctnnb1 tm2Kem/KnwJ ; The Jackson Laboratories, Bar Harbor, ME; ). Double transgenic Amhr2 Cre/+ ;Ctnnb1 flox/+ offspring derived from this first mating were then crossed to generate conditional mutant (Amhr2Cre/+;Ctnnb1 d/d ) and control (Amhr2 Cre/+ ;Ctnnb1 d/+ or Ctnnb1 flox/flox ) littermates. Attempts were made to induce decidualization using both natural (pregnancy) and artificial (intrauterine sesame oil injections during pseudopregnancy; ) means in control mice expressing β-catenin in the stromal compartment, as well as in mutant Amhr2 Cre/+ ;Ctnnb1 d/d mice. To study the proliferative/mitotic effects of steroids on endometrial tissue from control and conditionally mutant female mice, ovariectomies were performed between three and five weeks of age. One week later, female mice were treated subcutaneously with steroid hormones as indicated in the legend of each figure. Tissues were collected at specified times, prepared for paraffin sectioning and analyzed for proliferation (BrdU labeling) and/or mitosis (phospho-histone H3 expression) as described below.
Messenger RNA and protein expression analyses
5’CCTCCTTTACGGTGGACAAA 3’ 5’ GCCACATCAAGAGGTTTGGT 3’
For immunohistochemical and immunofluorescent analyses, whole implantation sites and mechanically decidualized uterine tissues were prepared from paraffin or frozen sections as previously described [11, 12]. Frozen uterine tissue sections from Rosa-EYFP transgenic mice were counterstained with DAPI and viewed directly using fluorescence microscopy. Sections processed for immunofluorescence were incubated with anti-total β-catenin antibodies at a dilution of 1:200 (Abcam) followed by incubation with an Alexafluor 546 conjugated secondary antibody (Invitrogen) and mounting medium containing DAPI.
For immunohistochemical detection of the active form of β-catenin, phospho-histone H3, ESR1 and progesterone receptor (PGR), paraffin embedded uterine sections were prepared as described elsewhere . Sections were incubated with primary antibody diluted [(1:100 for anti-active β-catenin (Millipore), 1:2000 for anti-phospho-histone H3 (Upstate Biotechnologies), 1:300 for anti-ESR1 (Santa Cruz) and 1:300 for anti-PGR (Dako)], then incubated with biotinylated secondary antibody (1:500; Santa Cruz Biotechnologies) and horseradish peroxidase-conjugated streptavidin (Vector Laboratories; Burlingame, CA). Sections were exposed to 3,3’-diaminobenzidine (DAB) substrate, counterstained with hematoxylin, dehydrated, and mounted for light microscopy. The mean ratio of mitotic epithelial cells in endometrial tissue sections was established by counting the number of phospho-histone H3-positive cells and dividing by the total number of cells (mean of three tissue sections obtained from three different regions of the uterus) following standard immunohistochemical detection. β-catenin expression was also assessed by immunofluorescence in primary human endometrial stromal cells (kindly provided by Dr. Bo Rueda, Massachusetts General Hospital) induced to undergo decidualization in vitro by provision of 100 μM cAMP, 36 nM 17β-estradiol benzoate, and 1 μM P4 for 12 days.
BrdU labeling and analysis of cellular proliferation
To assess cell proliferation in the individual epithelial and stromal compartments, control and mutant female mice were first ovariectomized at three to five weeks of age and allowed to clear endogenous ovarian-derived sex steroids for at least one week. Female mice then received E2 (100 ng s.c. in 100 μl sesame oil) on two consecutive days to prime the uterus and six days later began one of the following steroid hormone treatments. For epithelial cell proliferation, female mice received a single s.c. injection of E2 (50 ng in 50 μl of sesame oil) (n = 5 controls, n = 3 mutants). For stromal cell proliferation, female mice were injected with P4 (1 mg s.c. in 100 μl sesame oil) for three consecutive days and the following day with E2 + P4 (50 ng and 1 mg respectively in 100 μl sesame oil)] (n = 8 controls and mutants). Then 16 hrs after the final steroid hormone injection, female mice were treated with 50 mg/kg body weight 5-bromo-2’-deoxyuridine (BrdU; i.p. in 250 μl saline) for 2 hours prior to euthanasia and uterine dissection. Tissues were prepared for paraffin embedding and one section (6 μm thick) from three different regions of each uterus were used to assess BrdU incorporation immunohistochemically using a BrdU staining kit (Invitrogen Corporation, Camarillo, CA) per manufacturer’s instructions. The mean percentages of BrdU positive cells in the luminal epithelium (LE) and stroma were calculated by establishing a ratio of BrdU positive cells divided by the total number of cells within the luminal epithelium or subluminal stromal compartment.
Experimental replication and statistical analysis
Each experiment was independently replicated a minimum of three times with different mice in each experiment. Data in graphs represent the mean ± SEM from replicated experiments. Assignment of mice to each experiment was made randomly. Raw data were analyzed with GraphPad PRISM software (version 4.0) for simple comparisons. Mean values were considered significantly different when p < 0.05.
β-catenin expression during uterine receptivity and stromal decidualization
Stromal β-catenin is necessary for establishing pregnancy
A role for stromal β-catenin in steroid hormone signaling
Adult endometrial functions are temporally regulated by sex steroid hormones that require interplay between the epithelial and underlying stromal compartments. Ovarian-derived E2 generated during each estrous/menstrual cycle stimulates epithelial cell proliferation. The proliferative epithelial response to E2 is largely an indirect event that involves stromal release of epithelial mitogens such as IGF-1 [22, 23]. It was recently established through conditional mutagenesis studies that stromal-derived ESR1 is fundamental for directing epithelial cell proliferation, while epithelial ESR1 is dispensable . In turn, ovarian P4 completely abolishes E2-induced epithelial cell proliferation in vivo. Clinically, P4 is applied prophylactically in some settings to treat estrogen-dependent endometrial cancer and to alleviate potential complications during hormone replacement therapies that can arise due to the unopposed actions of estrogens. These fundamental actions of E2 and P4 within the endometrium are further validated in pharmacological studies where steroid hormone actions are attenuated, as well as through the use of mutant mice deficient in expression of ESR1 and PGR.
Amhr2 Cre/+ ;Ctnnb1 d/d mice are infertile, which engenders two previously unappreciated points for consideration. First, that deletion of Ctnnb1 from the stromal, but not epithelial, compartment results in failed decidualization, suggests that this transcriptional co-activator mediates steroid hormone actions in the endometrium that are critical for fertility. Further investigation is needed to determine if β-catenin interacts in parallel with PGR, forming a complex that in turn regulates expression of genes in stromal tissue whose encoded products contribute to decidualization. Precedence for the convergence of β-catenin and steroid hormone signaling pathways has been established in the uterus. Alternatively, the PGR and β-catenin signaling pathways may work in series where PGR results in activation of another pathway, such as WNTs that in turn utilize β-catenin function. This scenario is supported by recent findings where WNT4 was shown to be a key regulator of normal postnatal uterine development and progesterone signaling during embryo implantation and decidualization . Additional evidence for a PGR-β-catenin interaction comes from in vitro decidualization studies using human stromal cells where PGR expression was shown to be essential for nuclear translocation of β-catenin .
The second point for consideration is that stromal β-catenin is necessary for transcriptional regulation of both stromal and epithelial factors that are important for initiating decidualization and embryo attachment. Stromal β-catenin-deficiency results in failed up-regulation of Ihh in the epithelium, as well as Ptch1 and Gli1 in the stroma suggesting that stromal P4 signaling mediates events not only in the stromal compartment, but also in the overlying epithelium. It is concluded from this investigation that stromal β-catenin is a component of the signaling conduit through which P4 coordinates events in the overlying epithelium. Recent tissue recombination studies involving the use of wild type and Pgr-null stroma and/or epithelia support this concept . Here, Simon et al. established that neonatal tissue recombinants containing wild type epithelium and PGR-deficient stroma were unable to show elevated levels if Ihh in the epithelium in response to P4 treatment .
Some studies have suggested direct inhibitory actions of P4 on E2-induced epithelial cell proliferation. During the time of embryo implantation on day 4 of pregnancy in mice the epithelium does not express PGR despite observation of clear progestational response on the epithelium [29, 30]. How then does P4 signal in the epithelium in the absence of PGRs? The “progestamedin hypothesis” suggests that P4-induced paracrine factors secreted from the stromal compartment indirectly regulate P4 actions on the epithelium . It was recently established that E2-induced epithelial proliferation is suppressed by P4 actions in the stromal compartment involving a HAND2-dependent mechanism . Progesterone induces the transcriptional inhibitor HAND2, which in turn suppresses specific members of the fibroblast growth factors family in the stromal compartment . Our study places β-catenin squarely in the middle of P4-dependent mesenchymal-to-epithelial signaling during the initiation of maternal:embryo interaction.
A number of signaling factors and down-stream transcription factors have been identified through mutant mouse studies as critical components coordinating decidualization. Some of these include IHH, WNT4, HOXA10, HOXA11, Src-kinase, BMP2 and COUP-TFII reviewed in . Indian hedgehog localizes to the epithelium in response to P4 at the time of embryo implantation, and tissue restricted deletion of the gene using the PgrR-Cre mouse model results in failed decidualization [33–35]. From our study it is clear that transcription of members of the IHH pathway is reduced in Amhr2 Cre/+ ;Ctnnb1 d/d uteri in response to steroid hormones; however, additional functional studies are necessary to determine exactly how β-catenin is linked to the IHH signaling pathway.
Uteri from Amhr2 Cre/+ ;Ctnnb1 d/d mice are smaller in size than control uteri, which could confound the interpretation of these results. However, four lines of evidence suggest that the failure of Amhr2 Cre/+ ;Ctnnb1 d/d uteri to decidualize stems from disruption of steroid hormone receptor signaling rather than from altered prenatal or early postnatal uterine development. First, expression studies reveal that uteri from Amhr2 Cre/+ ;Ctnnb1 d/d mice have the potential to respond normally to E2 and P4 in that uterine mRNA and protein levels of ESR1 and PGR do not differ between control and mutant female mice. Second, uteri from control and mutant female mice display a normal response to E2, at least in terms of epithelial proliferation and stromal imbibition. Since the stromal compartment mediates the proliferative response in the epithelium, our findings indicate that the uterine stromal compartment of Amhr2 Cre/+ ;Ctnnb1 d/d mice is fully capable of disseminating proliferative signals to the epithelium. Third, the actions of P4 are not completely ablated in the uteri of Amhr2 Cre/+ ;Ctnnb1 d/d mice, since several genes previously shown to be targets of P4 action show the expected pattern of expression. For instance, Hmga2 (high mobility group AT-hook 2), Cdkl1 (cyclin-dependent kinase-like 1), and Ldb2 (LIM domain binding 2) were shown to be down-regulated by P4 treatment in vivo. Based on our microarray analysis each of these genes was down-regulated similarly in control Ctnnb1 flox/flox and mutant Amhr2 Cre/+ ;Ctnnb1 d/d uteri in vivo (data not shown). Conversely, S100a6 (calcyclin), Irg-1 (immune responsive gene-1) and Fst (follistatin), three genes shown to be up-regulated by P4, were equitably up-regulated in Ctnnb1 flox/flox and Amhr2 Cre/+ ;Ctnnb1 d/d uteri (data not shown). Fourth, indifferent stromal cell proliferation was observed in response to a hormone regimen consistent with early pregnancy. This suggests that the proliferative stromal cell response to P4 is not dependent upon β-catenin. In sum, these findings indicate that β-catenin deficiency in the stromal compartment of Amhr2 Cre/+ ;Ctnnb1 d/d uteri results in aberrant gene expression of a specific cassette of P4-dependent genes, several of which belong to the IHH signaling cascade, but that other P4 responses are normal.
Two functional studies were previously published on β-catenin in the uterus. In the first, β-catenin activity was indirectly assessed through the use of Tcf/Lef-LacZ transgenic mice . Here, β-galactosidase activity was used to identify coupling of β-catenin with the TCF/LEF transcriptional complex in situ. Based on this model, β-catenin activity was observed in the luminal epithelium and circular smooth muscle, an event that required the presence of an embryo. It was concluded that β-catenin was no longer active by late DOP5. However, β-catenin activity was defined by its ability to activate the Tcf/Lef-LacZ transgene, and β-catenin function was not addressed using deletional analysis (e.g., gene knockdown or mutant mice deficient in β-catenin). Additionally, while we and others  have since demonstrated the presence of active (i.e., dephosphorylated and nuclear) β-catenin in decidualizing stromal cells, Mohamed et al. were unable to detect transcriptional activity for the TCF/LEF complex in the stromal compartment, suggesting β-catenin may regulate gene expression within the stromal compartment by a TCF/LEF-independent mechanism.
More recently, Jeong et al. used the Pgr-Cre transgenic mouse line to delete β-catenin from PGR-expressing tissues, including all compartments of the uterus . Using this model system, β-catenin deficiency in the entire uterus resulted in pleiotropic effects leading to infertility, most likely because of the inability of stromal cells to terminally differentiate and E2-induced morphological defects. The design, and therefore the conclusion, of our study differ to some extent from this previous report. First, while uteri from Amhr2 Cre/+ ;Ctnnb1 d/d female mice lack expression of β-catenin in the myometrial and stromal compartments, as with the Pgr-Cre model, expression of β-catenin was retained in luminal and glandular epithelia using the Amhr2 Cre mouse line. Second, deletion of β-catenin in all compartments of the uterus resulted in metaplastic formation of the luminal epithelium in the intact mouse . Analysis of the ovaries indicated that ovarian function was preserved. Jeong et al., concluded that β-catenin deficiency in the epithelium was the source of the metaplastic phenotype. This conclusion is well justified in that mutations in the human Ctnnb1 gene are commonly associated with endometrial hyperplasia. Although our data does not rule out control of epithelial metaplasia by epithelial β-catenin, they indicate that, since Amhr2 Cre/+ ;Ctnnb1 d/d mutant uteri also develop metaplasia, albeit with reduced severity and incidence, the lack of β-catenin in stroma alone can dictate formation of epithelial metaplasia. As with β-catenin, deletion of APC, a component of the β-catenin signaling pathway, from the uterine stromal compartment results in a more severe phenotype where endometrial hyperplasia and carcinogenesis are observed .
Because β-catenin is connected to a multitude of cellular processes, we investigated the functional requirement of β-catenin in the stromal compartment of the endometrium for decidualization and responsiveness to steroid hormones. Our findings indicate that β-catenin is essential for early events in the terminal differentiation of uterine stromal cells. While it is well established that the stromal compartment indirectly coordinates epithelial cell proliferation through production of paracrine growth factors, deletion of stromal β-catenin did not alter E2-stimulated epithelial cell mitosis. Our study also provides evidence that the stromal compartment, through activation of β-catenin, mediates as least some of the actions of P4 on the epithelium. It will now be important to delineate upstream signaling pathways that activate stromal β-catenin and to identify β-catenin target genes that are necessary for disseminating steroid hormone actions on the epithelium, in addition to its role in decidualization within the stromal compartment.
This work was supported in part by NIH HD052701 and HD066297.
- Kurita T, Cooke PS, Cunha GR: Epithelial-stromal tissue interaction in paramesonephric (Mullerian) epithelial differentiation. Dev Biol. 2001, 240: 194-211. 10.1006/dbio.2001.0458.View ArticlePubMed
- Abrahamsohn PA, Zorn TM: Implantation and decidualization in rodents. J Exp Zool. 1993, 266: 603-628. 10.1002/jez.1402660610.View ArticlePubMed
- Hewitt SC, Harrell JC, Korach KS: Lessons in estrogen biology from knockout and transgenic animals. Annu Rev Physiol. 2005, 67: 285-308. 10.1146/annurev.physiol.67.040403.115914.View ArticlePubMed
- O'Brien JE, Peterson TJ, Tong MH, Lee EJ, Pfaff LE, Hewitt SC, Korach KS, Weiss J, Jameson JL: Estrogen-induced proliferation of uterine epithelial cells is independent of estrogen receptor alpha binding to classical estrogen response elements. J Biol Chem. 2006, 281: 26683-26692. 10.1074/jbc.M601522200.View ArticlePubMed
- Hou X, Tan Y, Li M, Dey SK, Das SK: Canonical Wnt signaling is critical to estrogen-mediated uterine growth. Mol Endocrinol. 2004, 18: 3035-3049. 10.1210/me.2004-0259.PubMed CentralView ArticlePubMed
- Ray S, Xu F, Wang H, Das SK: Cooperative control via lymphoid enhancer factor 1/T cell factor 3 and estrogen receptor-alpha for uterine gene regulation by estrogen. Mol Endocrinol. 2008, 22: 1125-1140. 10.1210/me.2007-0445.PubMed CentralView ArticlePubMed
- Grigoryan T, Wend P, Klaus A, Birchmeier W: Deciphering the function of canonical Wnt signals in development and disease: conditional loss- and gain-of-function mutations of beta-catenin in mice. Genes Dev. 2008, 22: 2308-2341. 10.1101/gad.1686208.PubMed CentralView ArticlePubMed
- Mikels AJ, Nusse R: Wnts as ligands: processing, secretion and reception. Oncogene. 2006, 25: 7461-7468. 10.1038/sj.onc.1210053.View ArticlePubMed
- Srinivas S, Watanabe T, Lin CS, William CM, Tanabe Y, Jessell TM, Costantini F: Cre reporter strains produced by targeted insertion of EYFP and ECFP into the ROSA26 locus. BMC Dev Biol. 2001, 1: 4-10.1186/1471-213X-1-4.PubMed CentralView ArticlePubMed
- Brault V, Moore R, Kutsch S, Ishibashi M, Rowitch DH, McMahon AP, Sommer L, Boussadia O, Kemler R: Inactivation of the beta-catenin gene by Wnt1-Cre-mediated deletion results in dramatic brain malformation and failure of craniofacial development. Development. 2001, 128: 1253-1264.PubMed
- Kashiwagi A, DiGirolamo CM, Kanda Y, Niikura Y, Esmon CT, Hansen TR, Shioda T, Pru JK: The postimplantation embryo differentially regulates endometrial gene expression and decidualization. Endocrinology. 2007, 148: 4173-4184. 10.1210/en.2007-0268.View ArticlePubMed
- Szotek PP, Chang HL, Zhang L, Preffer F, Dombkowski D, Donahoe PK, Teixeira J: Adult mouse myometrial label-retaining cells divide in response to gonadotropin stimulation. Stem Cells. 2007, 25: 1317-1325. 10.1634/stemcells.2006-0204.View ArticlePubMed
- Gavert N, Ben-Ze'ev A: Beta-catenin signaling in biological control and cancer. J Cell Biochem. 2007, 102: 820-828. 10.1002/jcb.21505.View ArticlePubMed
- Herington JL, Bi J, Martin JD, Bany BM: Beta-catenin (CTNNB1) in the mouse uterus during decidualization and the potential role of two pathways in regulating its degradation. J Histochem Cytochem. 2007, 55: 963-974. 10.1369/jhc.7A7199.2007.View ArticlePubMed
- Rider V, Isuzugawa K, Twarog M, Jones S, Cameron B, Imakawa K, Fang J: Progesterone initiates Wnt-beta-catenin signaling but estradiol is required for nuclear activation and synchronous proliferation of rat uterine stromal cells. J Endocrinol. 2006, 191: 537-548. 10.1677/joe.1.07030.View ArticlePubMed
- Haegel H, Larue L, Ohsugi M, Fedorov L, Herrenknecht K, Kemler R: Lack of beta-catenin affects mouse development at gastrulation. Development. 1995, 121: 3529-3537.PubMed
- Jamin SP, Arango NA, Mishina Y, Hanks MC, Behringer RR: Requirement of Bmpr1a for Mullerian duct regression during male sexual development. Nat Genet. 2002, 32: 408-410. 10.1038/ng1003.View ArticlePubMed
- Arango NA, Szotek PP, Manganaro TF, Oliva E, Donahoe PK, Teixeira J: Conditional deletion of beta-catenin in the mesenchyme of the developing mouse uterus results in a switch to adipogenesis in the myometrium. Dev Biol. 2005, 288: 276-283. 10.1016/j.ydbio.2005.09.045.View ArticlePubMed
- Deutscher E, Hung-Chang Yao H: Essential roles of mesenchyme-derived beta-catenin in mouse Mullerian duct morphogenesis. Dev Biol. 2007, 307: 227-236. 10.1016/j.ydbio.2007.04.036.PubMed CentralView ArticlePubMed
- Martin L, Finn CA: Duration of progesterone treatment required for a stromal response to oestradiol-17-beta in the uterus of the mouse. J Endocrinol. 1969, 44: 279-280. 10.1677/joe.0.0440279.View ArticlePubMed
- Jeong JW, Lee HS, Franco HL, Broaddus RR, Taketo MM, Tsai SY, Lydon JP, Demayo FJ: Beta-catenin mediates glandular formation and dysregulation of beta-catenin induces hyperplasia formation in the murine uterus. Oncogene. 2009, 28: 31-40. 10.1038/onc.2008.363.PubMed CentralView ArticlePubMed
- Zhu L, Pollard JW: Estradiol-17beta regulates mouse uterine epithelial cell proliferation through insulin-like growth factor 1 signaling. Proc Natl Acad Sci. 2007, 104: 15847-15851. 10.1073/pnas.0705749104.PubMed CentralView ArticlePubMed
- Chen B, Pan H, Zhu L, Deng Y, Pollard JW: Progesterone inhibits the estrogen-induced phosphoinositide 3-kinase–>AKT–>GSK-3beta–>cyclin D1–>pRB pathway to block uterine epithelial cell proliferation. Mol Endocrinol. 2005, 19: 1978-1990. 10.1210/me.2004-0274.View ArticlePubMed
- Winuthayanon W, Hewitt SC, Orvis GD, Behringer RR, Korach KS: Uterine epithelial estrogen receptor alpha is dispensable for proliferation but essential for complete biological and biochemical responses. Proc Natl Acad Sci. 2010, 107: 19272-19275. 10.1073/pnas.1013226107.PubMed CentralView ArticlePubMed
- Martin L, Finn CA: Hormonal regulation of cell division in epithelial and connective tissues of the mouse uterus. J Endocrinol. 1968, 41: 363-371. 10.1677/joe.0.0410363.View ArticlePubMed
- Franco HL, Dai D, Lee KY, Rubel CA, Roop D, Boerboom D, Jeong JW, Lyson JP, Bagchi IC, Bagchi MK, Demayo FJ: WNT4 is a key regulator of normal postnatal uterine development and progesterone signaling during embryo implanation and decidualization in the mouse. FASEB J. 2011, 25: 1176-1187. 10.1096/fj.10-175349.PubMed CentralView ArticlePubMed
- Cloke B, Huhtinen K, Fusi L, Kajihara T, Yliheikkilä M, Ho KK, Teklenburg G, Lavery S, Jones MC, Trew G, Kim JJ, Lam EW, Cartwright JE, Poutanen M, Brosens JJ: The androgen and progesterone receptors regulate distinct gene networks and cellular functions in decidualizing endometrium. Endocrinology. 2008, 149: 4462-4474. 10.1210/en.2008-0356.View ArticlePubMed
- Simon L, Speiwak KA, Ekman GC, Kim J, Lydon JP, Bagchi MK, Bagchi IC, DeMayo FJ, Cooke PS: Stromal progesterone receptors mediate induction of Indian Hedgehog (IHH) in uterine epithelium and its downstream targets in uterine stroma. Endocrinology. 2009, 150: 3871-3876. 10.1210/en.2008-1691.PubMed CentralView ArticlePubMed
- Tan J, Paria BC, Dey SK, Das SK: Differential uterine expression of estrogen and progesterone receptors correlates with uterine preparation for implantation and decidualization in the mouse. Endocrinology. 1999, 140: 5310-5321. 10.1210/en.140.11.5310.PubMed CentralPubMed
- Bazer FW, Slayden OD: Progesterone-induced gene expression in uterine epithelia; a myth perpetuated by conventional wisdom. Biol Reprod. 2008, 79: 1008-1009. 10.1095/biolreprod.108.072702.View ArticlePubMed
- Li Q, Kannan A, DeMayo FJ, Lyson JP, Cooke PS, Yamagishi H, Srivastava D, Bagchi MK, Bagchi IC: The antiproliferative action of progesterone in uterine epithelium is mediated by Hand2. Science. 2011, 331: 912-916. 10.1126/science.1197454.PubMed CentralView ArticlePubMed
- Franco HL, Jeong JW, Tsai SY, Lydon JP, DeMayo FJ: In vivo analysis of progesterone receptor action in the uterus during embryo implantation. Semin Cell Dev Biol. 2008, 19: 178-186. 10.1016/j.semcdb.2007.12.001.View ArticlePubMed
- Khatua A, Wang X, Ding T, Zhang Q, Reese J, DeMayo FJ, Paria BC: Indian hedgehog, but not histidine decarboxylase or amphiregulin, is a progesterone-regulated uterine gene in hamsters. Endocrinology. 2006, 147: 4079-4092. 10.1210/en.2006-0231.View ArticlePubMed
- Lee K, Jeong J, Kwak I, Yu CT, Lanske B, Soegiarto DW, Toftgard R, Tsai MJ, Tsai S, Lydon JP, DeMayo FJ: Indian hedgehog is a major mediator of progesterone signaling in the mouse uterus. Nat Genet. 2006, 38: 1204-1209. 10.1038/ng1874.View ArticlePubMed
- Matsumoto H, Zhao X, Das SK, Hogan BL, Dey SK: Indian hedgehog as a progesterone-responsive factor meditating epithelial-mesenchymal interactions in the mouse uterus. Dev Biol. 2002, 245: 280-290. 10.1006/dbio.2002.0645.View ArticlePubMed
- Jeong JW, Lee KY, Han SJ, Aronow BJ, Lydon JP, O'Malley BW, DeMayo FJ: The p160 steroid receptor coactivator 2, SRC-2, regulates murine endometrial function and regulates progesterone-independent and -dependent gene expression. Endocrinology. 2007, 148: 4238-4250. 10.1210/en.2007-0122.View ArticlePubMed
- Cheon YP, Li Q, Xu X, DeMayo FJ, Bagchi IC, Bagchi MK: A genomic approach to identify novel progesterone receptor regulated pathways in the uterus during implantation. Mol Endocrinol. 2002, 16: 2853-2871. 10.1210/me.2002-0270.View ArticlePubMed
- Mohamed OA, Jonnaert M, Labelle-Dumais C, Kuroda K, Clarke HJ, Dufort D: Uterine Wnt/beta-catenin signaling is required for implantation. Proc Natl Acad Sci. 2005, 102: 8579-8584. 10.1073/pnas.0500612102.PubMed CentralView ArticlePubMed
- Tanwar PS, Zhang L, Roberts DJ, Teixeira JM: Stromal deletion of the APC tumor suppressor in mice triggers development of endometrial cancer. Cancer Res. 2011, 71: 1-13. 10.1158/1538-7445.AM2011-1.View Article
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.