The placenta is a nonsupportive microenvironment for cancer cells. We showed that breast cancer cells (BCCL) were eliminated from placental implantation sites. During implantation, the placenta manipulates its surrounding matrix, which may induce BCCL elimination. Here, we explored the effect of placenta-induced ECM manipulations on BCCL. During experiments, BCCL (MCF-7/T47D) were cultured on placenta/BCCL-conditioned ECM (Matrigel used for first trimester placenta/BCCL culture and cleared by NH4OH). After culturing the cells, we analyzed cancer cell phenotype (death, count, aggregation, MMP) and signaling (microarray analysis and pathway validation). We found that the BCCL did not attach to previous placental implantation sites and instead, similarly to anoikis-resistant cells, migrated away, displayed increased MMP levels/activity, and formed aggregates in distant areas. T47D were less affected than the MCF-7 cells, since MCF-7 also showed modest increases in cell death, EMT, and increased proliferation. Microarray analysis of the MCF-7 highlighted changes in the integrin, estrogen, EGFR, and TGFb pathways. Indeed, placental ECM reduced ERa, induced Smad3/JNK phosphorylation and increased integrin-a5 expression (RGD-dependent integrin) in the BCCL. Addition of RGD or TGFbR/JNK inhibitors reversed the phenotypic changes. This study helps explain the absence of metastases to the placenta and why advanced cancer is found in pregnancy, and provides possible therapeutic targets for anoikis-resistant cells.
First trimester human placenta prevents breast cancer cell attachment to the matrix: The role of extracellular matrix.
Specimen part, Treatment
View SamplesFor data usage terms and conditions, please refer to http://www.genome.gov/27528022 and http://www.genome.gov/Pages/Research/ENCODE/ENCODEDataReleasePolicyFinal2008.pdf
Mapping and analysis of chromatin state dynamics in nine human cell types.
Disease, Cell line
View SamplesChromatin profiling has emerged as a powerful means for annotating genomic elements and detecting regulatory activity. Here we generate and analyze a compendium of epigenomic maps for nine chromatin marks across nine cell types, in order to systematically characterize cis-regulatory elements, their cell type-specificities, and their functional interactions. We first identify recurrent combinations of histone modifications and use them to annotate diverse regulatory elements including promoters, enhancers, transcripts and insulators in each cell type. We next characterize the dynamics of these elements, revealing meaningful patterns of activity for promoter states and exquisite cell type-selectivity for enhancer states. We define multi-cell activity profiles that reflect the patterns of enhancer state activity across cell types, as well as analogous profiles for gene expression, regulatory motif enrichments, and expression of the corresponding regulators. We use correlations between these profiles to link enhancers to putative target genes, to infer cell type-specific activators and repressors, and to predict and validate functional regulator binding motifs in specific chromatin states. These functional annotations and regulatory predictions enable us to revisit intergenic single-nucleotide polymorphisms (SNPs) associated with human disease in genome-wide association studies (GWAS). We find that for several diseases, top-scoring SNPs are precisely positioned within enhancer elements specifically active in relevant cell types. In several cases a disease variant affects a motif instance for one of the predicted causal regulators, thus providing a potential mechanistic explanation for the disease association. Our study presents a general framework for applying multi-cell chromatin state analysis to decipher cis-regulatory connections and their role in health and disease.
Mapping and analysis of chromatin state dynamics in nine human cell types.
Cell line
View SamplesTo identify gene expression that distinguishes hematopoietic cells that express PRAME from those that do not, normal CD34+ cells with forced PRAME expression were compared to cells without PRAME expression in culture over time (days 4, 7, 14) using Affymetrix HU-133A microarrays
The preferentially expressed antigen in melanoma (PRAME) inhibits myeloid differentiation in normal hematopoietic and leukemic progenitor cells.
Specimen part, Time
View SamplesIn theses experimetns we have analized the differential gene expression profile in human trabecular meshwork cells phagocytically challenged to E. coli and pigment under physiological and oxidative stress conditions using affymetrix microarrays
Up-regulated expression of extracellular matrix remodeling genes in phagocytically challenged trabecular meshwork cells.
Specimen part
View SamplesRecent studies have been successful at utilizing ectopic expression of transcription factors to generate induced cardiomyocytes (iCMs) from fibroblasts, albeit at a low frequency in vitro. This work investigates the influence of small molecules that have been previously reported to improve differentiation to cardiomyocytes as well as reprogramming to iPSCs in conjunction with ectopic expression of the transcription factors Hand2, Nkx2.5, Gata4, Mef2C, and Tbx5 on the conversion to functional iCMs. We utilized a reporter system in which the calcium indicator GCaMP is driven by the cardiac Troponin T promoter to quantify iCM yield. The TGF inhibitor, SB431542 (SB), was identified as a small molecule capable of increasing the conversion of both mouse embryonic fibroblasts and adult cardiac fibroblasts to iCMs up to ~5 fold. Further characterization revealed that inhibition of TGF by SB early in the reprogramming process led to the greatest increase in conversion of fibroblasts to iCMs in a dose-responsive manner. Global transcriptional analysis at Day 3 post-induction of the transcription factors revealed an increased expression of genes associated with the development of cardiac muscle in the presence of SB compared to the vehicle control. Incorporation of SB in the reprogramming process increases the efficiency of iCM generation, one of the major goals necessary to enable the use of iCMs for discovery-based applications and for the clinic.
Inhibition of TGFβ signaling increases direct conversion of fibroblasts to induced cardiomyocytes.
Specimen part, Treatment
View SamplesWe used microarrays to detail the global programme of gene expression underlying palate development by persistent expression in R26Pax3 mice and identified distinct classes of up-regulated and down-regulated genes during this process.
Persistent expression of Pax3 in the neural crest causes cleft palate and defective osteogenesis in mice.
No sample metadata fields
View SamplesTo investigate the role of miR-29b on the changes in expression of genes involved in the synthesis and deposition of extracellular matrix in human trabecular meshwork cells (HTM).
Role of miR-29b on the regulation of the extracellular matrix in human trabecular meshwork cells under chronic oxidative stress.
Cell line
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Imprecise transcription termination within Escherichia coli greA leader gives rise to an array of short transcripts, GraL.
No sample metadata fields
View SamplesWhile studying greA expression, we noted presence of an intrinsic terminator in the leader region of greA mRNA transcript. We found this terminator to be quite efficient both in vivo and in vitro. This region seems to be conserved among many enteric bacteria. Judging from fitness experiments, the resulting short RNAs (50-59nt long) exert biological effects. This lead us to propose that greA leader region encodes a novel small non-coding RNA that we collectively call GraL.
Imprecise transcription termination within Escherichia coli greA leader gives rise to an array of short transcripts, GraL.
No sample metadata fields
View Samples