Tumor relapse is associated with dismal prognosis, but responsible biological principles remain incompletely understood. To isolate and characterize relapse-inducing cells, we used genetic engineering and proliferation-sensitive dyes in patient-derived xenografts of acute lymphoblastic leukemia (ALL). We identified a rare subpopulation that resembled relapse-inducing cells with combined properties of long-term dormancy, treatment resistance, and stemness. Single-cell and bulk expression profiling revealed their similarity to primary ALL cells isolated from pediatric and adult patients at minimal residual disease (MRD). Therapeutically adverse characteristics were reversible, as resistant, dormant cells became sensitive to treatment and started proliferating when dissociated from the in vivo environment. Our data suggest that ALL patients might profit from therapeutic strategies that release MRD cells from the niche. Overall design: Gene expression profiles from two PDX ALL Samples (ALL-199 & ALL-265) were generated for either dormant (LRC) vs. dividing (non-LRC) cells or drug treated vs. non-treated cells. For single cell analysis one mouse were analyzed for each condition.
Characterization of Rare, Dormant, and Therapy-Resistant Cells in Acute Lymphoblastic Leukemia.
Specimen part, Treatment, Subject
View SamplesPediatric high-grade gliomas (pHGGs) harboring the K27M mutation of H3F3A (histone H3.3) are characterized by global reduction of the repressive histone mark H3K27me3 and DNA hypomethylation.
Reduced H3K27me3 and DNA hypomethylation are major drivers of gene expression in K27M mutant pediatric high-grade gliomas.
Sex, Age, Disease, Disease stage
View SamplesThe Hippo pathway plays a crucial in organ size control during development and tissue homeostasis in adult life. To examine a role for Hippo signaling in the intestinal epithelium, we analyzed gene expression patterns in the mouse intestinal epithelilum transfected with siRNAs or expression plasmids for shRNAs targeting the Hippo pathway effectors, YAP and TAZ.
Dual role of YAP and TAZ in renewal of the intestinal epithelium.
Sex, Age, Specimen part, Treatment
View SamplesExpression profiles of 917 pathway repoter genes were determined by AmpliSeq-RNA in primary human hepatocytes treated with Diclofenac and a test compound 3 hours after treatment. Overall design: Vehicle control, diclofenac, and three doses of the test compound (small-molecule neurotransmitter receptor antagonist) were applied to three primary cell lines, with three biological replicates in each group. In some treatment groups read-outs were only available for two samples. All together 41 samples were profiled.
Pathway reporter genes define molecular phenotypes of human cells.
No sample metadata fields
View SamplesThe ERK family of MAP kinase plays a critical role in growth factor-stimulated cell cycle progression from G0/G1 to S phase. But, how sustained activation of ERK promotes G1 progression has remained unclear. Here, our systematic analysis on the temporal program of ERK-dependent gene expression shows that sustained activation of ERK is required for induction and maintenance of the decreased expression levels of a set of genes. Moreover, our cell biological analysis reveals that these ERK-dependent downregulated genes have the ability to block S phase entry. Cessation of ERK activation at mid or late G1 leads to a rapid increase of these anti-proliferative genes and results in the inhibition of S phase entry. These findings uncover an important mechanism by which the duration of ERK activation regulates cell cycle progression through dynamic changes in gene expression, and identify novel ERK target genes crucial for the regulation of cell cycle progression.
Continuous ERK activation downregulates antiproliferative genes throughout G1 phase to allow cell-cycle progression.
No sample metadata fields
View SamplesIn skeletal muscle differentiation, muscle-specific genes are regulated by two groups of transcription factors, the MyoD and MEF2 families, which work together to drive the differentiation process. Here we show that ERK5 regulates muscle cell fusion through Klf transcription factors. The inhibition of ERK5 activity suppresses muscle cell fusion with minimal effects on the expression of MyoD, MEF2, and their target genes. Promoter analysis coupled to microarray assay reveals that Klf-binding motifs are highly enriched in the promoter regions of ERK5-dependent upregulated genes. Remarkably, Klf2 and Klf4 expression are also upregulated during differentiation in an ERK5-dependent manner, and knockdown of Klf2 or Klf4 specifically suppresses muscle cell fusion. Moreover, we show that the Sp1 transcription factor links ERK5 to Klf2/4, and that nephronectin, a Klf transcriptional target, is involved in muscle cell fusion. Therefore, an ERK5/Sp1/Klf module plays a key role in the fusion process during skeletal muscle differentiation.
ERK5 regulates muscle cell fusion through Klf transcription factors.
Cell line, Time
View SamplesAtypical teratoid/rhabdoid tumor (ATRT) is one of the most common brain tumors in infants. Although the prognosis of ATRT patients is poor, some patients respond favorably to current treatments, suggesting molecular inter-tumor heterogeneity. To investigate this further, we genetically and epigenetically analyzed a large series of human ATRTs. Three distinct molecular subgroups of ATRTs, associated with differences in demographics, tumor location, and type of SMARCB1 alterations, were identified. Whole-genome DNA and RNA sequencing found no recurrent mutations in addition to SMARCB1 that would explain the differences between subgroups. Whole-genome bisulfite sequencing and H3K27Ac chromatin-immunoprecipitation sequencing of primary tumors, however, revealed clear differences, leading to the identification of subgroup-specific regulatory networks and potential therapeutic targets.
Atypical Teratoid/Rhabdoid Tumors Are Comprised of Three Epigenetic Subgroups with Distinct Enhancer Landscapes.
Sex, Age
View SamplesWhole exome sequencing identified frequent driver mutations in a series of paediatric glioblastomas
Driver mutations in histone H3.3 and chromatin remodelling genes in paediatric glioblastoma.
Sex, Age, Disease, Disease stage
View SamplesIt remains unclear how the ectopic expression of defined transcription factors induces dynamic changes in gene expression profiles that establish a pluripotent state during direct cell reprogramming. In the present study, we first identified a temporal gene expression program during the reprogramming process. Promoter analyses then predicted the role of two forkhead box transcription factors, Foxd1 and Foxo1, as mediators of the gene expression program. Knockdown of Foxd1 or Foxo1 reduced the number of induced pluripotent stem cells (iPSCs). The knockout of Foxd1 prevented the downstream transcription program, including the expression of reprogramming marker genes. Interestingly, the expression level of Foxd1 was also transiently increased in a small population of cells in the middle stage of reprogramming. The presence or absence of Foxd1 expression in this stage was correlated with a future cell fate as iPSCs or non-reprogrammed cells. These results suggest that Foxd1 is a mediator and indicator of the successful progression of the gene expression program in cell reprogramming.
Foxd1 is a mediator and indicator of the cell reprogramming process.
Specimen part, Time
View SamplesIt remains unclear how the ectopic expression of defined transcription factors induces dynamic changes in gene expression profiles that establish a pluripotent state during direct cell reprogramming. In the present study, we first identified a temporal gene expression program during the reprogramming process. Promoter analyses then predicted the role of two forkhead box transcription factors, Foxd1 and Foxo1, as mediators of the gene expression program. Knockdown of Foxd1 or Foxo1 reduced the number of induced pluripotent stem cells (iPSCs). The knockout of Foxd1 prevented the downstream transcription program, including the expression of reprogramming marker genes. Interestingly, the expression level of Foxd1 was also transiently increased in a small population of cells in the middle stage of reprogramming. The presence or absence of Foxd1 expression in this stage was correlated with a future cell fate as iPSCs or non-reprogrammed cells. These results suggest that Foxd1 is a mediator and indicator of the successful progression of the gene expression program in cell reprogramming.
Foxd1 is a mediator and indicator of the cell reprogramming process.
No sample metadata fields
View Samples