Endometrial epithelial Arid1a is essential in early pregnancy
Ontology highlight
ABSTRACT: Endometrial epithelial Arid1a is necessary for normal gene expression and maintenance of a receptive endometrium at pre-implantation stage in mice. We used RNA-sequencing to determine the differences in uterine gene expression resulting from deletion of endometrial epithelial Arid1a.
Project description:TP53 and ARID1A are frequently mutated across cancer but rarely in the same primary tumor. Endometrial cancer has the highest TP53-ARID1A mutual exclusivity rate. However, the functional relationship between TP53 and ARID1A mutations in the endometrium has not been elucidated. We used genetically engineered mice and in vivo genomic approaches to discern both unique and overlapping roles of TP53 and ARID1A in the endometrium. TP53 loss with oncogenic PIK3CA*H1047R in the endometrial epithelium results in features of endometrial hyperplasia, adenocarcinoma, and intraepithelial carcinoma. Mutant endometrial epithelial cells were transcriptome profiled and compared to control cells and ARID1A/PIK3CA mutant endometrium. In the context of either TP53 or ARID1A loss, PIK3CA mutant endometrium exhibited inflammatory pathway activation, but other gene expression programs differed based on TP53 or ARID1A status, such as epithelial-to-mesenchymal transition. Gene expression patterns observed in the genetic mouse models are reflective of human tumors with each respective genetic alteration. Consistent with TP53-ARID1A mutual exclusivity, the p53 pathway is activated following ARID1A loss in the endometrial epithelium, where ARID1A normally directly represses p53 pathway genes in vivo, including the stress-inducible transcription factor, ATF3. However, co-existing TP53-ARID1A mutations led to invasive adenocarcinoma associated with mutant ARID1A-driven ATF3 induction, reduced apoptosis, TP63+ squamous differentiation and invasion. These data suggest TP53 and ARID1A mutations drive shared and distinct tumorigenic programs in the endometrium and promote invasive endometrial cancer when existing simultaneously. Hence, TP53 and ARID1A mutations may co-occur in a subset of aggressive or metastatic endometrial cancers, with ARID1A loss promoting squamous differentiation and the acquisition of invasive properties.
Project description:TP53 and ARID1A are frequently mutated across cancer but rarely in the same primary tumor. Endometrial cancer has the highest TP53-ARID1A mutual exclusivity rate. However, the functional relationship between TP53 and ARID1A mutations in the endometrium has not been elucidated. We used genetically engineered mice and in vivo genomic approaches to discern both unique and overlapping roles of TP53 and ARID1A in the endometrium. TP53 loss with oncogenic PIK3CA*H1047R in the endometrial epithelium results in features of endometrial hyperplasia, adenocarcinoma, and intraepithelial carcinoma. Mutant endometrial epithelial cells were transcriptome profiled and compared to control cells and ARID1A/PIK3CA mutant endometrium. In the context of either TP53 or ARID1A loss, PIK3CA mutant endometrium exhibited inflammatory pathway activation, but other gene expression programs differed based on TP53 or ARID1A status, such as epithelial-to-mesenchymal transition. Gene expression patterns observed in the genetic mouse models are reflective of human tumors with each respective genetic alteration. Consistent with TP53-ARID1A mutual exclusivity, the p53 pathway is activated following ARID1A loss in the endometrial epithelium, where ARID1A normally directly represses p53 pathway genes in vivo, including the stress-inducible transcription factor, ATF3. However, co-existing TP53-ARID1A mutations led to invasive adenocarcinoma associated with mutant ARID1A-driven ATF3 induction, reduced apoptosis, TP63+ squamous differentiation and invasion. These data suggest TP53 and ARID1A mutations drive shared and distinct tumorigenic programs in the endometrium and promote invasive endometrial cancer when existing simultaneously. Hence, TP53 and ARID1A mutations may co-occur in a subset of aggressive or metastatic endometrial cancers, with ARID1A loss promoting squamous differentiation and the acquisition of invasive properties.
Project description:Successful embryo implantation into a receptive endometrium requires mutual endometrial-embryo communication. Recently, the function of extracellular vehicles (EVs) in cell-to-cell interaction in embryo-maternal interactions has been investigated. We explored isolated endometrial derived EVs, using RL95-2 cells as a model of a receptive endometrium, influenced by menstrual cycle hormones estrogen (E2; proliferative phase) progesterone (P4; secretory phase) and estrogen plus progesterone (E2P4; the receptive phase). EV sized particles were isolated by differential centrifugation and size exclusion chromatography. Nanoparticle tracking analysis was used to examine the different concentration and size of particles and EV proteomic analysis per-formed using shotgun label-free mass spectrometry. Our results showed that although endome-trial derived EVs were secreted in numbers independent of hormonal stimulation, EVs sizes were statistically modified by it. Proteomics analysis showed that hormone treatment changes affect the endometrial EVs proteome, with proteins enhanced within the EV E2P4 group shown to be in-volved in different processes such as embryo implantation, endometrial receptivity, and embryo development, supporting the concept of a communication system between the embryo and the maternal endometrium via EVs.
Project description:The fate of the human endometrium is determined during the mid-luteal window of implantation, coinciding with differentiation of endometrial stromal cells (EnSCs) into specialized decidual cells. Upon embryo implantation, differentiating EnSCs transform the endometrium into the decidua of pregnancy; whereas falling progesterone levels in the absence of pregnancy lead to tissue breakdown and menstruation. We used single-cell RNA sequencing to map the transcriptomic changes in primary EnSCs along a decidual time-course and in response to withdrawal of differentiation signals. We demonstrate that decidual transformation starts with a precipitous transcriptional response, which is followed by synchronous transition of EnSCs through intermediate states before emerging as divergent subpopulations, representing decidual cells and senescent decidual cells. Single-cell analysis of timed luteal phase biopsies identified multiple endometrial epithelial subpopulations and immune cells, most prominently uterine NK cells. In the stroma, transition from receptive to post-receptive endometrial state was marked by progression of EnSCs along diverging transcriptional trajectories, involving genes with conserved branching dynamics in vivo and in vitro. Our findings indicate that specification of EnSCs into distinct decidual subpopulations underpins endometrial fate decisions during the window of implantation.
Project description:The majority of pregnancy losses result from implantation failure. Successful embryo implantation involves a delicate interaction between the receptive uterus and an implantation-competent blastocyst. Understanding the mechanisms regulating the endometrial receptivity during preimplantation are essential for improving pregnancy outcomes. Mitogen-inducible gene 6 (MIG-6) is a key mediator of progesterone signaling in the endometrium.MIG-6 loss results in implantation failure due to non-receptive endometrium. We applied single cell RNA sequencing to determine the composition of different cell types and functions within non-receptive endometrium from uterine specific Mig-6 knock-out (Pgrcre/+Mig-6f/f; Mig-6d/d) mice. Mig-6d/d mice revealed altered gene expression in the epithelial and stromal cells. We identified key gene expression changes in the non-receptive endometrium of Mig-6d/d mice, providing valuable insights into the role of progesterone signaling in implantation.
Project description:Receptivity of the uterus is essential for embryo implantation and progression of pregnancy. Acquisition of receptivity involves major molecular and cellular changes in the endometrial lining of the uterus from its non-receptive state at ovulation, to its receptive state four days later. The precise molecular mechanisms underlying this transition remain to be fully characterized. Here, we aimed to generate a comprehensive profile of the uterine transcriptome in the peri-ovulatory and peri-implantation states, and to define the differences between them, in the mouse. High throughput RNA-sequencing was utilized to identify genes and pathways expressed in the endometrium of C57Bl/6 female mice on day 3.5 post-coitum after mating with BALB/c males, compared to the endometrium of unmated estrous females (n=3-4 biological replicates). RNA-sequencing and analysis using Ingenuity Pathway Analysis software revealed that, compared to the endometrium at estrus, 388 genes were differentially expressed in the endometrium on day 3.5 post-coitum (FDR ≤ 0.05). Several upstream regulators are implicated in the transition to receptivity including several cytokines, steroid hormones, prostaglandin E2, and vascular endothelial growth factor A. The transcriptional changes indicate substantial changes in the uterine immune and vascular systems during the pre-implantation phase, with the functional terms Angiogenesis, Chemotaxis, and Lymphangiogenesis predominating. This analysis confirms that the transcriptome of a receptive uterus is vastly different to the non-receptive uterus and identifies several genes and regulatory pathways not previously associated with implantation. This dataset will serve as a valuable tool and resource for future research on the molecular mechanisms of uterine receptivity.
Project description:Embryo implantation is a key step in establishing pregnancy and a major limiting factor in IVF. Implantation requires the endometrium, the inner lining of the uterus, to transform from a non-receptive to a receptive state, to allow embryos to attach to the surface and enter into the tissue. However, the fundamental mechanisms governing receptivity are not well understood. Here we show that transmembrane protein podocalyxin is a major and clinically significant factor regulating human endometrial receptivity. Podocalyxin is expressed in all endometrial epithelial cells in the non-receptive state but is selectively down-regulated in the luminal epithelium at receptivity. We present evidence that podocalyxin critically governs the barrier function of the endometrial epithelium, likely as an intrinsic protective mechanism, rendering it non-receptive to an embryo. In addition, podocalyxin suppresses genes promoting receptivity (eg LIF, CSF1) but stimulates those inhibiting implantation (eg WNT7A, LEFTY2). Down-regulation of podocalyxin in the luminal epithelium, likely mediated by progesterone, selectively converts the endometrial surface to a more adhesive state that facilitates embryo attachment and penetration. Furthermore, inadequate down-regulation of podocalyxin in the endometrial luminal epithelium is associated with poorer implantation rates in IVF. We thus propose that podocalyxin promotes the barrier function of human endometrial epithelial cells and critically regulates receptivity for embryo implantation.
Project description:The inner uterine lining (endometrium) has been shown to have a distinct methylation pattern that changes throughout the menstrual cycle. However, not much is known about how the endometrial methylome affects endometrial receptivity to implanting embryo in the second half of the menstrual cycle. The aim of the present study was to use genome-wide technologies and a paired study design to characterize the endometrial methylome in pre-receptive and receptive endometrium sampled from 17 healthy women within the same menstrual cycle.
Project description:Arid1a has a critical role for modulating endometrial gland develop that is required for normal uterine function and fertility after maturity. We used microarrays to detail the mechanism underlying Arid1a loss during postnatal development.
Project description:Implantation is the attachment of embryo in the endometrium. Failure in implantation is a major cause of early pregnancy loss. During implantation, the temporal uterine lumen closure can help embryo attach to the uterus. In pigs, extending of endometrial folds to form interlocking finger-like projections is a main cause leads to uterine lumen closure during attachment time, but the underlying mechanisms are largely unknown. Our data reveal that pig uterine luminal epithelium (LE) migrate in coordinated groups during extending of endometrial folds. Moreover, the MALDI-TOF MS based N-glycomic characterization of porcine endometrium revealed α2,6-linked sialic acid are highly expressed in pig uterine LE during extending of endometrial folds. To investigated the mechanisms by which α2,6-sialylated proteins in formation of the endometrial folding during implantation in pigs, the α2,6-sialylated proteins in pig uterine LE were characterized by proteomic analysis and those proteins that are involved in cell adhesion, such as E-cadherin, were detected. Finally, our in vivo and in vitro data show that α2,6-sialylation of E-cadherin occurs in accompany with collective epithelial migration. The results provide new insight into the mechanism of pig implantation by identifying that α2,6-sialylation of cell adhesion molecules may participate in formation of extending of endometrial folds through promoting of collective migration of uterine LE.