Primordial follicle assembly is a process that occurs in the embryonic or early post natal ovary in which oocyte nests break down to form individual primordial follicles. The size of this initial pool of primordial follicles in part determines the reproductive lifespan of the female. Connective tissue growth factor (CTGF) was identified as a potential regulatory candidate for this process in a previous microarray analysis of follicle development. The current study examines the effects of CTGF and associated transforming growth factor beta 1 (TGFbeta-1) on follicle assembly. Ovaries were removed from newborn rat pups and placed in an organ culture system for two days to measure the effect of these factors on follicle assembly. In addition, ovaries were cultured and treated for ten days to determine the potential of CTGF and TGFbeta-1 to manipulate the primordial follicle pool size over a longer developmental time period. The ovaries treated with CTGF for two days were found to have an increased proportion of assembled follicles. TGFbeta-1 had no effect on primordial follicle assembly and in combination with CTGF decreased oocyte number in the ovary after two days of culture. Over ten days of treatment only the combined treatment of CTGF and TGFbeta-1 was found to cause an increase in the proportion of assembled follicles. Interestingly, treatment with TGFbeta-1 alone resulted in fewer total oocytes in the ovary and decreased the primordial follicle pool size after ten days of culture. Observations indicate that CTGF alone or in combination with TGFbeta-1 stimulates primordial follicle assembly and TGFbeta-1 can decrease the primordial follicle pool size. CTGF was found to regulate the ovarian transcriptome during primordial follicle assembly and an integrative network of genes was identified. CTGF is one of the first growth factors shown to promote primordial follicle assembly, while TGFbeta-1 is one of the first factors shown to decrease the primordial follicle pool size. These observations suggest the possibility of manipulating primordial follicle pool size and influencing female reproductive lifespan.
Induction of ovarian primordial follicle assembly by connective tissue growth factor CTGF.
Sex, Specimen part
View SamplesOvarian primordial follicles are critical for female reproduction and comprise a finite pool of gametes arrested in development. A systems biology approach was used to identify regulatory gene networks essential for primordial follicle development. Transcriptional responses to eight different growth factors known to influence primordial follicles were used to construct a bionetwork of regulatory genes involved in primordial follicle development. Over 1500 genes were found to be regulated by the various growth factors and a network analysis identified critical gene modules involved in a number of signaling pathways and cellular processes. A set of 55 genes was identified as potential critical regulators of these gene modules, and a subnetwork associated with development was determined. Within the network two previously identified regulatory genes were confirmed (i.e. Pdgfa and Fgfr2) and a new factor was identified, connective tissue growth factor (CTGF). CTGF was tested in ovarian organ cultures and found to stimulate primordial follicle development. Therefore, the relevant gene network associated with primordial follicle development was validated and the critical genes and pathways involved in this process were identified. This is one of the first applications of network analysis to a normal developmental process. These observations provide insights into potential therapeutic targets for preventing ovarian disease and promoting female reproduction.
Gene bionetwork analysis of ovarian primordial follicle development.
Sex, Specimen part, Treatment
View SamplesThe current study was designed to investigate the actions of Anti-Mllerian Hormone (AMH) on primordial follicle assembly. Ovarian primordial follicles develop from the breakdown of oocyte nests during fetal development for the human and immediately after birth in rodents. AMH was found to inhibit primordial follicle assembly, decrease the initial primordial follicle pool size and promote the persistence of small oocyte nests in a rat ovarian organ culture. The AMH expression was found to be primarily in the stromal tissue of the ovaries at this period of development, suggesting a stromal-epithelial cell interaction for primordial follicle assembly. AMH was found to promote alterations in the ovarian transcriptome during primordial follicle assembly with over 200 genes with altered expression. A gene network was identified suggesting a potential central role for the Fgf2/Nudt6 antisense transcript in the follicle assembly process. A number of signal transduction pathways are regulated by AMH actions on the ovarian transcriptome, in particular the transforming growth factor beta (TGF) signaling process. AMH is the first hormone/protein shown to have an inhibitory action on primordial follicle assembly. Due to the critical role of the primordial follicle pool size for female reproduction, elucidation of the factors, such as AMH, that regulate the assembly process will provide insights into potential therapeutics to manipulate the pool size and female reproduction.
Inhibitory actions of Anti-Müllerian Hormone (AMH) on ovarian primordial follicle assembly.
Sex, Specimen part
View SamplesFanconi anemia (FA) is a genetic disorder characterized by congenital abnormalities, bone marrow failure and increased susceptibility to cancer. Of the fifteen FA proteins, Fanconi anemia group C (FANCC) is one of eight FA core complex components of the FA pathway. Unlike other FA core complex proteins, FANCC is mainly localized in the cytoplasm, where it is thought to function in apoptosis, redox regulation, cytokine signaling and other processes. Previously, we showed that regulation of FANCC involved proteolytic processing during apoptosis. To elucidate the biological significance of this proteolytic modification, we searched for molecular interacting partners of proteolytic FANCC fragments. Among the candidates obtained, the transcriptional corepressor protein C-terminal binding protein-1 (CtBP1) interacted directly with FANCC and other FA core complex proteins. Although not required for stability of the FA core complex or ubiquitin ligase activity, CtBP1 is essential for proliferation, cell survival and maintenance of chromosomal integrity. Expression profiling of CtBP1-depleted and FA-depleted cells revealed that several genes were commonly up- and down-regulated, including the Wnt antagonist Dickkopf-1 (DKK1). These findings suggest that FA and Wnt signaling via CtBP1 could share common effectors.
Fanconi anemia proteins interact with CtBP1 and modulate the expression of the Wnt antagonist Dickkopf-1.
Cell line
View SamplesEmbryonal Tumors with Multilayered Rosettes (ETMRs) have recently been described as a new entity of rare pediatric brain tumors with fatal outcome. We show here that ETMRs are characterized by a parallel activation of Shh- and Wnt-signaling. Co-activation of these pathways in murine neural precursors is sufficient to induce ETMR-like tumors in vivo that resemble their human counterparts based on histology and global gene expression analyses, and point to apical radial glia cells as the possible tumor cell-of-origin. Overexpression of LIN28A, which is a hallmark of human ETMRs, augments Sonic Hedgehog (Shh)- and Wnt-signaling in these precursor cells through downregulation of let7-miRNA, and LIN28A/let7a interaction with the Shh-pathway was detected at the level of Gli mRNA. Finally, human ETMR cells that were transplanted into immunocompromised host mice were responsive to the Shh-inhibitor Arsenic trioxide (ATO). Our findings provide a novel mouse model to study this tumor type, demonstrate the driving role of Wnt- and Shh-activation in the growth of ETMRs and propose downstream inhibition of Shh-signaling as a therapeutic option for patients with ETMRs.
A mouse model for embryonal tumors with multilayered rosettes uncovers the therapeutic potential of Sonic-hedgehog inhibitors.
Specimen part
View SamplesThe objective of this experiment was to test the effect, at a transcrptomic level, of lymphotoxin-beta receptor activation in HBV-infected differentiated HepaRG cells
Specific and nonhepatotoxic degradation of nuclear hepatitis B virus cccDNA.
No sample metadata fields
View SamplesThe aim of this study was to investigate correlations between early subclinical findings (10 and 90 day histology and gene expression data) and late outcomes (transplant glomerulopathy and graft loss) in positive crossmatch kidney transplants (+XMKTx).
Early subclinical inflammation correlates with outcomes in positive crossmatch kidney allografts.
Specimen part
View SamplesEpithelial-mesenchymal transition (EMT) and mesenchymal-epithelial transition (MET) facilitate breast cancer (BC) metastasis, however stable molecular changes that result as a consequence of these processes remain poorly defined. Therefore, we sought to identify molecular markers that could distinguish tumor cells that had completed the EMT:MET cycle in the hopes of identifying and targeting unique aspects of metastatic tumor outgrowth.Therefore, normal murine mammary gland (NMumG) cells transformed by overexpression of EGFR (NME) cells were cultured in the presence of TGF-beta1 (5 ng/ml) for 4 weeks, at which point TGF-beta1 supplementation was discontinued and the cells were allowed to recover for an additional 4 weeks (Post-TGF-Rec). Total RNA was prepared from unstimulated cells (Pre-TGF) of similar passage and compared by microarray analysis.
Fibroblast growth factor receptor splice variants are stable markers of oncogenic transforming growth factor β1 signaling in metastatic breast cancers.
Specimen part
View SamplesThe protease activity of the paracaspase MALT1 plays an important role in antigen receptor-mediated lymphocyte activation by controlling the activity of the transcription factor NF-kB and is thus essential for the expression of inflammatory target genes.
MALT1 Protease Activity Controls the Expression of Inflammatory Genes in Keratinocytes upon Zymosan Stimulation.
Treatment
View SamplesThis SuperSeries is composed of the SubSeries listed below.
The transcriptional profile of mesenchymal stem cell populations in primary osteoporosis is distinct and shows overexpression of osteogenic inhibitors.
Sex, Age, Specimen part, Disease
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