The mouse Gene Expression Database (GXD): 2021 update.

The Gene Expression Database (GXD; www.informatics.jax.org/expression.shtml) is an extensive and well-curated community resource of mouse developmental gene expression information. For many years, GXD has collected and integrated data from RNA in situ hybridization, immunohistochemistry, RT-PCR, northern blot, and western blot experiments through curation of the scientific literature and by collaborations with large-scale expression projects. Since our last report in 2019, we have continued to acquire these classical types of expression data; developed a searchable index of RNA-Seq and microarray experiments that allows users to quickly and reliably find specific mouse expression studies in ArrayExpress (https://www.ebi.ac.uk/arrayexpress/) and GEO (https://www.ncbi.nlm.nih.gov/geo/); and expanded GXD to include RNA-Seq data. Uniformly processed RNA-Seq data are imported from the EBI Expression Atlas and then integrated with the other types of expression data in GXD, and with the genetic, functional, phenotypic and disease-related information in Mouse Genome Informatics (MGI). This integration has made the RNA-Seq data accessible via GXD's enhanced searching and filtering capabilities. Further, we have embedded the Morpheus heat map utility into the GXD user interface to provide additional tools for display and analysis of RNA-Seq data, including heat map visualization, sorting, filtering, hierarchical clustering, nearest neighbors analysis and visual enrichment.

The mouse Gene Expression Database (GXD): 2019 update.

The mouse Gene Expression Database (GXD) is an extensive, well-curated community resource freely available at www.informatics.jax.org/expression.shtml. Covering all developmental stages, GXD includes data from RNA in situ hybridization, immunohistochemistry, RT-PCR, northern blot and western blot experiments in wild-type and mutant mice. GXD's gene expression information is integrated with the other data in Mouse Genome Informatics and interconnected with other databases, placing these data in the larger biological and biomedical context. Since the last report, the ability of GXD to provide insights into the molecular mechanisms of development and disease has been greatly enhanced by the addition of new data and by the implementation of new web features. These include: improvements to the Differential Gene Expression Data Search, facilitating searches for genes that have been shown to be exclusively expressed in a specified structure and/or developmental stage; an enhanced anatomy browser that now provides access to expression data and phenotype data for a given anatomical structure; direct access to the wild-type gene expression data for the tissues affected in a specific mutant; and a comparison matrix that juxtaposes tissues where a gene is normally expressed against tissues, where mutations in that gene cause abnormalities.

The mouse Gene Expression Database (GXD): 2017 update.

The Gene Expression Database (GXD; www.informatics.jax.org/expression.shtml) is an extensive and well-curated community resource of mouse developmental expression information. Through curation of the scientific literature and by collaborations with large-scale expression projects, GXD collects and integrates data from RNA in situ hybridization, immunohistochemistry, RT-PCR, northern blot and western blot experiments. Expression data from both wild-type and mutant mice are included. The expression data are combined with genetic and phenotypic data in Mouse Genome Informatics (MGI) and made readily accessible to many types of database searches. At present, GXD includes over 1.5 million expression results and more than 300 000 images, all annotated with detailed and standardized metadata. Since our last report in 2014, we have added a large amount of data, we have enhanced data and database infrastructure, and we have implemented many new search and display features. Interface enhancements include: a new Mouse Developmental Anatomy Browser; interactive tissue-by-developmental stage and tissue-by-gene matrix views; capabilities to filter and sort expression data summaries; a batch search utility; gene-based expression overviews; and links to expression data from other species.

The mouse Gene Expression Database (GXD): 2014 update.

The Gene Expression Database (GXD; http://www.informatics.jax.org/expression.shtml) is an extensive and well-curated community resource of mouse developmental expression information. GXD collects different types of expression data from studies of wild-type and mutant mice, covering all developmental stages and including data from RNA in situ hybridization, immunohistochemistry, RT-PCR, northern blot and western blot experiments. The data are acquired from the scientific literature and from researchers, including groups doing large-scale expression studies. Integration with the other data in Mouse Genome Informatics (MGI) and interconnections with other databases places GXD's gene expression information in the larger biological and biomedical context. Since the last report, the utility of GXD has been greatly enhanced by the addition of new data and by the implementation of more powerful and versatile search and display features. Web interface enhancements include the capability to search for expression data for genes associated with specific phenotypes and/or human diseases; new, more interactive data summaries; easy downloading of data; direct searches of expression images via associated metadata; and new displays that combine image data and their associated annotations. At present, GXD includes >1.4 million expression results and 250,000 images that are accessible to our search tools.

The mouse gene expression database: New features and how to use them effectively.

The Gene Expression Database (GXD) is an extensive and freely available community resource of mouse developmental expression data. GXD curates and integrates expression data from the literature, via electronic data submissions, and by collaborations with large-scale projects. As an integral component of the Mouse Genome Informatics Resource, GXD combines expression data with genetic, functional, phenotypic, and disease-related data, and provides tools for the research community to search for and analyze expression data in this larger context. Recent enhancements include: an interactive browser to navigate the mouse developmental anatomy and find expression data for specific anatomical structures; the capability to search for expression data of genes located in specific genomic regions, supporting the identification of disease candidate genes; a summary displaying all the expression images that meet specified search criteria; interactive matrix views that provide overviews of spatio-temporal expression patterns (Tissue × Stage Matrix) and enable the comparison of expression patterns between genes (Tissue × Gene Matrix); data zoom and filter utilities to iteratively refine summary displays and data sets; and gene-based links to expression data from other model organisms, such as chicken, Xenopus, and zebrafish, fostering comparative expression analysis for species that are highly relevant for developmental research.

GXD: a community resource of mouse Gene Expression Data.

The Gene Expression Database (GXD) is an extensive, easily searchable, and freely available database of mouse gene expression information (www.informatics.jax.org/expression.shtml). GXD was developed to foster progress toward understanding the molecular basis of human development and disease. GXD contains information about when and where genes are expressed in different tissues in the mouse, especially during the embryonic period. GXD collects different types of expression data from wild-type and mutant mice, including RNA in situ hybridization, immunohistochemistry, RT-PCR, and northern and western blot results. The GXD curators read the scientific literature and enter the expression data from those papers into the database. GXD also acquires expression data directly from researchers, including groups doing large-scale expression studies. GXD currently contains nearly 1.5 million expression results for over 13,900 genes. In addition, it has over 265,000 images of expression data, allowing users to retrieve the primary data and interpret it themselves. By being an integral part of the larger Mouse Genome Informatics (MGI) resource, GXD's expression data are combined with other genetic, functional, phenotypic, and disease-oriented data. This allows GXD to provide tools for researchers to evaluate expression data in the larger context, search by a wide variety of biologically and biomedically relevant parameters, and discover new data connections to help in the design of new experiments. Thus, GXD can provide researchers with critical insights into the functions of genes and the molecular mechanisms of development, differentiation, and disease.

Benzocyclobutene (BCB) Polymer as Amphibious Buffer Layer for Graphene Field-Effect Transistor.

Owing to the scattering and trapping effects, the interfaces of dielectric/graphene or substrate/graphene can tailor the performance of field-effect transistor (FET). In this letter, the polymer of benzocyclobutene (BCB) was used as an amphibious buffer layer and located at between the layers of substrate and graphene and between the layers of dielectric and graphene. Interestingly, with the help of nonpolar and hydrophobic BCB buffer layer, the large-scale top-gated, chemical vapor deposited (CVD) graphene transistors was prepared on Si/SiO2 substrate, its cutoff frequency (fT) and the maximum cutoff frequency (fmax) of the graphene field-effect transistor (GFET) can be reached at 12 GHz and 11 GHz, respectively.

Notch2 is required in somatic cells for breakdown of ovarian germ-cell nests and formation of primordial follicles.

BACKGROUND: In the mouse ovary, oocytes initially develop in clusters termed germ-cell nests. Shortly after birth, these germ-cell nests break apart, and the oocytes individually become surrounded by somatic granulosa cells to form primordial follicles. Notch signaling plays essential roles during oogenesis in Drosophila, and recent studies have suggested that Notch signaling also plays an essential role during oogenesis and ovary development in mammals. However, no in vivo loss-of-function studies have been performed to establish whether Notch family receptors have an essential physiological role during normal ovarian development in mutant mice. RESULTS: Female mice with conditional deletion of the Notch2 gene in somatic granulosa cells of the ovary exhibited reduced fertility, accompanied by the formation of multi-oocyte follicles, which became hemorrhagic by 7 weeks of age. Formation of multi-oocyte follicles resulted from defects in breakdown of the primordial germ-cell nests. The ovaries of the Notch2 conditional mutant mice had increased numbers of oocytes, but decreased numbers of primordial follicles. Oocyte numbers in the Notch2 conditional mutants were increased not by excess or extended cellular proliferation, but as a result of decreased oocyte apoptosis. CONCLUSIONS: Our work demonstrates that Notch2-mediated signaling in the somatic-cell lineage of the mouse ovary regulates oocyte apoptosis non-cell autonomously, and is essential for regulating breakdown of germ-cell nests and formation of primordial follicles. This model provides a new resource for studying the developmental and physiological roles of Notch signaling during mammalian reproductive biology.

Survey and clinical considerations of gender identity in lower primary school children.

BACKGROUND: Gender consciousness directly affects the development of gender identity, which is a continuous and lifelong process. Meanwhile, hospitalization is a part of many children's lives and has an impact on their gender development. AIM: To investigate the current situation of gender identity in lower primary school children by conducting a survey of 202 hospitalized children in the lower grades and to provide a theoretical basis and foundation for the cultivation of gender identity and medical treatment of children based on the results. This study aims to inspire clinical medical staff to scientifically and reasonably arrange hospital wards for lower primary school children and pay attention to gender protection during the medical treatment process and to help children shape a unified and clear gender identity, which will enable them to better integrate into society and promote their personality development. METHODS: The gender consciousness scale for elementary and middle school students was used for the survey. RESULTS: Gender identity was already present in lower primary school children. The children's gender roles and gender equality consciousness were strong, exceeding the critical value, but their gender characteristics, gender identity, and gender ideal consciousness were weak. Children aged 6 had the weakest gender identity, and girls had significantly stronger gender identity than boys. CONCLUSION: Gender identity is already present in lower primary school children, providing a basis and inspiration for the cultivation of gender identity and medical treatment of lower primary school children. Clinical medical staff should be aware of and understand these results and should scientifically and reasonably arrange hospital wards for lower primary school children.

The Role of Signaling Pathways in Pancreatic Cancer Targeted Therapy.

Signaling pathways play significant roles in the occurrence, development, and treatment of pancreatic cancer (PC). The main treatment options are surgery, chemotherapy, radiotherapy, arterial infusion chemotherapy in interventional therapy, and immunotherapy. Many studies have shown that signaling pathways perform a function in the occurrence and development of PC, for instance, phosphoinositide 3-kinase (PI3K)/AKT, nuclear factor-κB, Ras, interleukin (IL)-17B/IL-17RB, Wnt, and hepatocyte growth factor/c-MET, which play roles in the proliferation, metastasis, invasion, inhibition of apoptosis, promotion of angiogenesis, and drug resistance of PC. Interaction of signaling pathways has an impact on the biological behavior of PC; for example, activation of the neurotensin/NTSR1 pathway, which can activate mitogen-activated protein kinase, nuclear factor-κB, and other pathways related to PC stem cells, play an important role in PC, and an increase in their number is associated with the Wnt/ß-catenin and PI3K pathways. Chemotherapy is the main method for the treatment of PC, but drug resistance limits its use. In addition, abnormal activation of IL-17B/IL-17RB signaling pathway is associated with drug resistance. This article discusses the signaling pathways that play different roles in the occurrence and development of PC, as well as current research on signaling pathways in PC treatment.

Bortezomib-loaded mixed micelles realize a "three-in-one" effect for enhanced breast cancer treatment.

Comprehensively regulating the TME is now regarded as a promising approach for cancer treatment. Herein, a novel "three-in-one" effect is presented for simultaneously killing tumor cells, inhibiting the EMT of CAFs, and improving immune responses. In this study, bortezomib (BTZ) is selected for the treatment of breast cancer; it has multiple pharmacological mechanisms for killing tumor cells through the NF-κB signaling pathway, inhibiting the activity of CAFs by activating caspase-3, and enhancing the function of CD8+ T cells by regulating the expression of immune-stimulating factors. To improve the druggability of BTZ in solid tumors, BTZ-loaded lipid/glycocholic acid mixed micelles (BTZ-LGs) were prepared to verify the "three-in-one" effect in killing tumor cells, inhibiting CAFs, and improving immune responses. In the present work, BTZ-LGs were verified to show enhanced in vitro cytotoxicity in both 4T1 cells and 4T1/NIH3T3 co-cultured cells, as well as a superior in vivo treatment effect in different tumor-bearing mouse models. Additionally, BTZ-LGs could regulate the expression of α-SMA, caspase-3, E-cadherin, and N-cadherin, indicating their good inhibiting ability on both tumor cells and CAFs. More importantly, immunological analysis revealed that BTZ-LGs promoted the expression of the immunostimulatory factor IL-2 in tumor tissues, activated anti-tumor T cells, and overcame tumor-induced CD8+ T cell dysfunction. All these findings suggest that BTZ-LGs can achieve a "three-in-one" effect in terms of killing tumor cells, suppressing CAFs, and improving immune responses. This simple and multi-effective therapeutic strategy offers a promising approach for cancer therapy.

The Notch-regulated ankyrin repeat protein is required for proper anterior-posterior somite patterning in mice.

The Notch-regulated ankyrin repeat protein (Nrarp) is a component of a negative feedback system that attenuates Notch pathway-mediated signaling. In vertebrates, the timing and spacing of formation of the mesodermal somites are controlled by a molecular oscillator termed the segmentation clock. Somites are also patterned along the rostral-caudal axis of the embryo. Here, we demonstrate that Nrarp-deficient embryos and mice exhibit genetic background-dependent defects of the axial skeleton. While progression of the segmentation clock occurred in Nrarp-deficient embryos, they exhibited altered rostrocaudal patterning of the somites. In Nrarp mutant embryos, the posterior somite compartment was expanded. These studies confirm an anticipated, but previously undocumented role for the Nrarp gene in vertebrate somite patterning and provide an example of the strong influence that genetic background plays on the phenotypes exhibited by mutant mice.

Generation of mice with a conditional null allele of the Jagged2 gene.

The Notch signaling pathway is an evolutionarily-conserved intercellular signaling mechanism, and mutations in its components disrupt embryonic development in many organisms and cause inherited diseases in humans. The Jagged2 (Jag2) gene, which encodes a ligand for Notch pathway receptors, is required for craniofacial, limb, and T cell development. Mice homozygous for a Jag2 null allele die at birth from cleft palate, precluding study of Jag2 function in postnatal and adult mice. We have generated a Jag2 conditional null allele by flanking the first two exons of the Jag2 gene with loxP sites. Cre-mediated deletion of the Jag2(flox) allele generates the Jag2(del2) allele, which behaves genetically as a Jag2 null allele. This Jag2 conditional null allele will enable investigation of Jag2 function in a variety of tissue-specific contexts.

The Notch ligand JAG1 is required for sensory progenitor development in the mammalian inner ear.

In mammals, six separate sensory regions in the inner ear are essential for hearing and balance function. Each sensory region is made up of hair cells, which are the sensory cells, and their associated supporting cells, both arising from a common progenitor. Little is known about the molecular mechanisms that govern the development of these sensory organs. Notch signaling plays a pivotal role in the differentiation of hair cells and supporting cells by mediating lateral inhibition via the ligands Delta-like 1 and Jagged (JAG) 2. However, another Notch ligand, JAG1, is expressed early in the sensory patches prior to cell differentiation, indicating that there may be an earlier role for Notch signaling in sensory development in the ear. Here, using conditional gene targeting, we show that the Jag1 gene is required for the normal development of all six sensory organs within the inner ear. Cristae are completely lacking in Jag1-conditional knockout (cko) mutant inner ears, whereas the cochlea and utricle show partial sensory development. The saccular macula is present but malformed. Using SOX2 and p27kip1 as molecular markers of the prosensory domain, we show that JAG1 is initially expressed in all the prosensory regions of the ear, but becomes down-regulated in the nascent organ of Corti by embryonic day 14.5, when the cells exit the cell cycle and differentiate. We also show that both SOX2 and p27kip1 are down-regulated in Jag1-cko inner ears. Taken together, these data demonstrate that JAG1 is expressed early in the prosensory domains of both the cochlear and vestibular regions, and is required to maintain the normal expression levels of both SOX2 and p27kip1. These data demonstrate that JAG1-mediated Notch signaling is essential during early development for establishing the prosensory regions of the inner ear.

Allogeneic Hematopoietic Stem Cell Transplant for Severe Aplastic Anemia: Current State and Future Directions.

Acquired severe aplastic anemia (SAA) is a rare and life-threatening bone marrow failure syndrome characterized by cytotoxic T-cells excessive activity, hematopoietic precursors decrease and peripheral blood (PB) pancytopenia. Patients with severe aplastic anemia (SAA) die 1 to 2 years after diagnosis due to fatal infections and/or hemorrhagic complications if they do not undergo any effective treatment. Nowadays, Immunosuppressive therapy (IST) and allogeneic hematopoietic stem cell transplantation (HSCT) are still the standard treatment for SAA. For patients younger than 40 years old, allogeneic HSCT is often the best choice. Recently, outcomes of matched unrelated donor and haploidentical donor transplantation have significantly improved, notably in some cases which are comparable to the result of matched related donor transplantation. Mixed chimerism status is more common in SAA post-transplantation patients, which is effected by conditioning regimen used in transplantation and is closely relevant to donor cells rejection and secondary graft failure. In this article, we briefly have reviewed the current state and future directions for SAA HSCT, and have shared our SAA data and transplant experience of the recent decade. We have analyzed the impact of conditioning regimen on engraftment and chimerism status in SAA transplantation, and have compiled our findings in this report.

Ghrelin Protects the Thymic Epithelium From Conditioning-Regimen-Induced Damage and Promotes the Restoration of CD4+ T Cells in Mice After Bone Marrow Transplantation.

BACKGROUND: The delay in immune reconstitution after hematopoietic stem cell transplantation (HSCT), especially a delay in central immune reconstitution, leads to opportunistic infections and disease relapse after transplantation and affects the long-term outcome of HSCT. This delay is mainly attributable to thymic damage after myeloablative chemotherapy and radiotherapy. METHODS: We established a model of allogeneic bone marrow transplantation (BMT) in mice and administered ghrelin (GRL) 7 days before the conditioning regimen or the day after BMT to explore the effect of GRL on thymus. RESULTS: All the GRL-treated mice, especially those administered GRL before the conditioning regimen, exhibited more intact thymic architecture and a more rapid restoration of CD4 T lymphocytes after BMT than those of the corresponding control mice. Moreover, the levels of T cell receptor excision circles were significantly higher in the mice treated with GRL before the conditioning regimen than in the control mice at 28 days after BMT. CONCLUSIONS: Our findings suggest that GRL may be a novel potential therapeutic approach to protecting the thymic epithelium from conditioning regimen-induced damage and promoting rapid and durable thymic and peripheral CD4 T cell recovery after HSCT.

Gene expression profiling of leiomyoma and myometrial smooth muscle cells in response to transforming growth factor-beta.

Altered expression of the TGF-beta system is recognized to play a central role in various fibrotic disorders, including leiomyoma. In this study we performed microarray analysis to characterize the gene expression profile of leiomyoma and matched myometrial smooth muscle cells (LSMC and MSMC, respectively) in response to the time-dependent action of TGF-beta and, after pretreatment with TGF-beta type II receptor (TGF-beta RII) antisense oligomer-blocking/reducing TGF-beta autocrine/paracrine actions. Unsupervised and supervised assessments of the gene expression values with a false discovery rate selected at P < or = 0.001 identified 310 genes as differentially expressed and regulated in LSMC and MSMC in a cell- and time-dependent manner by TGF-beta. Pretreatment with TGF-beta RII antisense resulted in changes in the expression of many of the 310 genes regulated by TGF-beta, with 54 genes displaying a response to TGF-beta treatment. Comparative analysis of the gene expression profile in TGF-beta RII antisense- and GnRH analog-treated cells indicated that these treatments target the expression of 222 genes in a cell-specific manner. Gene ontology assigned these genes functions as cell cycle regulators, transcription factors, signal transducers, tissue turnover, and apoptosis. We validated the expression and TGF-beta time-dependent regulation of IL-11, TGF-beta-induced factor, TGF-beta-inducible early gene response, early growth response 3, CITED2 (cAMP response element binding protein-binding protein/p300-interacting transactivator with ED-rich tail), Nur77, Runx1, Runx2, p27, p57, growth arrest-specific 1, and G protein-coupled receptor kinase 5 in LSMC and MSMC using real-time PCR. Together, the results provide the first comprehensive assessment of the LSMC and MSMC molecular environment targeted by autocrine/paracrine action of TGF-beta, highlighting potential involvement of specific genes whose products may influence the outcome of leiomyoma growth and fibrotic characteristics by regulating inflammatory response, cell growth, apoptosis, and tissue remodeling.

Leiomyoma and myometrial gene expression profiles and their responses to gonadotropin-releasing hormone analog therapy.

Gene microarray was used to characterize the molecular environment of leiomyoma and matched myometrium during growth and in response to GnRH analog (GnRHa) therapy as well as GnRHa direct action on primary cultures of leiomyoma and myometrial smooth muscle cells (LSMC and MSMC). Unsupervised and supervised analysis of gene expression values and statistical analysis in R programming with a false discovery rate of P < or = 0.02 resulted in identification of 153 and 122 differentially expressed genes in leiomyoma and myometrium in untreated and GnRHa-treated cohorts, respectively. The expression of 170 and 164 genes was affected by GnRHa therapy in these tissues compared with their respective untreated group. GnRHa (0.1 microm), in a time-dependent manner (2, 6, and 12 h), targeted the expression of 281 genes (P < or = 0.005) in LSMC and MSMC, 48 of which genes were found in common with GnRHa-treated tissues. Functional annotations assigned these genes as key regulators of processes involving transcription, translational, signal transduction, structural activities, and apoptosis. We validated the expression of IL-11, early growth response 3, TGF-beta-induced factor, TGF-beta-inducible early gene response, CITED2 (cAMP response element binding protein-binding protein/p300-interacting transactivator with ED-rich tail), Nur77, growth arrest-specific 1, p27, p57, and G protein-coupled receptor kinase 5, representing cytokine, common transcription factors, cell cycle regulators, and signal transduction, at tissue levels and in LSMC and MSMC in response to GnRHa time-dependent action using real-time PCR, Western blotting, and immunohistochemistry. In conclusion, using different, complementary approaches, we characterized leiomyoma and myometrium molecular fingerprints and identified several previously unrecognized genes as targets of GnRHa action, implying that local expression and activation of these genes may represent features differentiating leiomyoma and myometrial environments during growth and GnRHa-induced regression.

Differential expression, regulation, and induction of Smads, transforming growth factor-beta signal transduction pathway in leiomyoma, and myometrial smooth muscle cells and alteration by gonadotropin-releasing hormone analog.

The objective of this study was to further elucidate the role of TGFbeta and GnRH analog (GnRHa) in leiomyoma growth and regression. We examined the expression of Smads, TGFbeta receptor intracellular signaling molecules, in leiomyoma and myometrial smooth muscle cells (LSMC and MSMC), and determined whether TGFbeta and GnRHa differentially regulate their expression and induction in these cells. Using semiquantitative RT-PCR, Western blot analysis, and immunohistochemistry, we demonstrated that leiomyoma, myometrium, LSMC, and MSMC express receptor-activated Smad3, common Smad4, and the inhibitory Smad7 mRNA and protein and showed that TGFbeta1, in a time-dependent manner, transiently induced Smad7 expression, with Smad3 and Smad4 remaining largely unchanged. TGFbeta1 increased the rate of Smad and phosphorylated Smad3 (pSmad3) induction in both cell types. Pretreatment with TGFbeta type II receptor antisense oligonucleotide resulted in a trend toward a lower TGFbeta-induced pSmad3. GnRHa, in a dose- and time-dependent manner, increased the expression of Smad7 mRNA and the rapid induction of Smad3, Smad4, and Smad7 as well as pSmad3, which declined to control values at doses above 1 micro M in MSMC, but not in LSMC. GnRHa-induced pSamd3 was partly inhibited by a GnRH antagonist (antide). We concluded that leiomyoma, myometrium, LSMC, and MSMC express Smads, which are differentially expressed, induced, and activated by TGFbeta and are altered as a result of GnRHa treatment. These results suggest that TGFbeta and GnRHa mediate their actions through cross-talk involving Smads and most likely other signaling pathways that result in leiomyoma growth and regression.

The expression of Smads in human endometrium and regulation and induction in endometrial epithelial and stromal cells by transforming growth factor-beta.

Human endometrium expresses TGF-beta and TGF-beta receptors where they regulate several endometrial biological activities implicated in embryo implantation, irregular bleeding, endometriosis, and cancer. In the present study, we determined the expression of Smads, intracellular signals that mediate TGF-beta receptors signals from the cell surface to the nucleus, in the endometrium as well as isolated endometrial epithelial (EEC) and stromal (ESC) cells. We also determined whether TGF-beta regulates the expression Smads and activates Smad3 in these cells and endometrial surface epithelial cell line (HES). Using semiquantitative RT-PCR, Western blot analysis, and immunohistochemistry, we found that endometrium, EEC, ESC, and HES express Smad3, -4, and -7 mRNA and protein and contain phosphorylated Smad3 (pSmad3). Smads and pSmad3 were localized in the epithelial and stromal cells with cytoplasmic/nuclear localization. TGF-beta in a dose- and time-dependent manner increased the expression of Smads mRNA and protein, the rate of pSmad3 activation, and Smad3 translocation into the nucleus in ESC and HES. The effect of TGF-beta on pSmad3 induction was, in part, abrogated by the pretreatment of HES and ESC with TGF-beta type II receptor antisense oligonucleotides. We conclude that human endometrium expresses the necessary components of Smad signaling pathway, whose expression and induction in endometrial epithelial and stromal cells are regulated by TGF-beta.