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GSE67415
Mus musculus
32 Downloadable Samples
Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Ebf1 is a transcription factor with documented, and dose dependent, functions in both normal and malignant B-lymphocyte development. In order to understand more about the role of Ebf1 in malignant transformation, we have investigated the impact of reduced functional Ebf1 dose on early B-cell progenitors. Gene expression analysis in loss and gain of function analysis suggested that Ebf1 was involved in the regulation of genes of importance for DNA repair as well as cell survival. Investigation of the level of DNA damage in steady state as well as after induction of DNA damage by UV light supported that pro-B cells lacking one functional allele of Ebf1 display a reduced ability to repair DNA damage. This was correlated to a reduction in expression of Rad51 and combined analysis of published 4C and chromatin Immuno precipitation data suggested that this gene is a direct target for Ebf1. Even though the lack of one allele of Ebf1 did not result in any dramatic increase of tumor formation, we noted a dramatic increase in the formation of pro-B cell leukemia in mice carrying a combined heterozygote mutation in the Ebf1 and Pax5 genes. Even though the tumors were phenotypically similar and stable, we noted a large degree of molecular heterogeneity well in line with a mechanism involving impaired DNA repair. Our data support the idea that Ebf1 controls homologous DNA repair in a dose dependent manner and that this may explain the frequent involvement of Ebf1 in human leukemia
Publication Title
Ebf1 heterozygosity results in increased DNA damage in pro-B cells and their synergistic transformation by Pax5 haploinsufficiency.
Sample Metadata Fields
Specimen part, Cell line, Time
View Samples- Homo sapiens
- 31 Downloadable Samples
NextSeq 500
Description
Activating signaling mutations are common in acute leukemia with KMT2A (previously MLL) rearrangements. Herein, we show that co-expression of FLT3-N676K and KMT2A-MLLT3 in human CD34+ cord blood cells primarily cause acute myeloid leukemia (AML) and rarely acute lymphoblastic leukemia (ALL) in immunodeficient mice. By contrast, expression of KMT2A-MLLT3 alone cause ALL, double-positive leukemia (DPL, expressing both CD33 and CD19), or bilineal leukemia (BLL, comprised of distinct myeloid and lymphoid leukemia cells), and rarely AML. Further, AML could only be serially propagated with maintained immunophenotype in secondary recipients when cells co-expressed KMT2A-MLLT3 and FLT3-N676K. Consistent with the idea that activated signaling would allow myeloid cells to engraft and maintain their self-renewal capacity, in a secondary recipient, a de novo KRAS-G13D was identified in myeloid cells previously expressing only KMT2A-MLLT3. Gene expression profiling revealed that KMT2A-MLLT3 DPL had a highly similar gene expression profile to ALL, with both expressing key lymphoid transcription factors and ALL cell surface markers, in line with the DPL cells being ALL cells with aberrant expression of CD33. Taken together, our results highlight the need for constitutive active signaling mutations for driving myeloid leukemia in a human xenograft model of KMT2A-R acute leukemia. Overall design: mRNA sequencing of various immunophenotypic populations from KMT2A-MLLT3 xenograft leukemias with or without FLT3-N676K generated using Illumina NextSeq 500.
Publication Title
FLT3<sup>N676K</sup> drives acute myeloid leukemia in a xenograft model of KMT2A-MLLT3 leukemogenesis.
Sample Metadata Fields
Specimen part, Subject
View Samples- Mus musculus
- 6 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
We have shown that removal of Lkb1 in chondorcytes results in enchondroma-like structure in postnatal mouse long bones. To furhter understand the role of Lkb1 in this process, we performed microarrrays to compare the transcriptional profile between control and conditional Lkb1 mutant (Col2a1-Cre; Lkb1c/c) chondrocytes.
Publication Title
Lkb1/Stk11 regulation of mTOR signaling controls the transition of chondrocyte fates and suppresses skeletal tumor formation.
Sample Metadata Fields
Specimen part
View Samples- Pseudomonas aeruginosa
- 15 Downloadable Samples
- Affymetrix Pseudomonas aeruginosa Array (paeg1a)
Description
Biofilm formation and type III secretion have been shown to be reciprocally regulated in P. aeruginosa, and it has been suggested that factors related to acute infection may be incompatible
Publication Title
Biofilms and type III secretion are not mutually exclusive in Pseudomonas aeruginosa.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 5 Downloadable Samples
- Affymetrix Human Genome U133A Array (hgu133a)
Description
This series includes the four major subtypes of pituitary adenomas and normal post-mortem pituitary tissue
Publication Title
Differential gene expression in pituitary adenomas by oligonucleotide array analysis.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 22 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Gonadotrope or null cell pituitary tumors present clinically with signs of hypogonadism and hypopituitarism, together with visual disturbances due to mass effects. Since there are no medical therapies, surgery and/or radiation are the only therapeutic options. To identify dysregulated genes and/or pathways that may play a role in tumorigenesis and/ or progression, molecular profiling was performed on 14 gonadotrope tumors and 9 normal human pituitaries from autopsy samples. Principle component analysis (PCA) revealed clear discrimination between tumor and normal pituitary gene expression profiles. Bioinformatic analysis identified specific genes and pathways that were highly differentially regulated, including a cohort of putative downstream effectors of p53 were repressed in gonadotrope pituitary tumors, including GADD45, GADD45 and Reprimo with concomitant downregulation of the upstream regulator, PLAGL1. PLAGL1 reexpression in gonadotrope cells did not directly modulate the downstream targets. Further functional analysis of GADD45 was performed. Overexpression of GADD45 in mouse gonadotrope cells blocked proliferation, increased rates of apoptosis in response to growth factor withdrawal and increased colony formation in soft agar. In contrast to prior studies with GADD45, methylation interference assays showed no evidence of epigenetic modification of the GADD45 promoter in pituitary tumors. Thus, our data suggest that many components downstream of p53 are suppressed in gonadotrope pituitary tumors. A novel candidate, GADD45 is low in tumors and reexpression blocks proliferation, survival and tumorigenesis in gonadotrope cells. Unlike GADD45, GADD45 is not methylated to block its expression. Together these studies identify new targets and mechanisms to explore concerning pituitary tumor initiation and progression.
Publication Title
Identification of growth arrest and DNA-damage-inducible gene beta (GADD45beta) as a novel tumor suppressor in pituitary gonadotrope tumors.
Sample Metadata Fields
Sex
View Samples- Homo sapiens
- 79 Downloadable Samples
Illumina human-6 v2.0 expression beadchip
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Gene expression profiling-based identification of molecular subtypes in stage IV melanomas with different clinical outcome.
Sample Metadata Fields
Sex, Specimen part
View Samples- Homo sapiens
- 57 Downloadable Samples
- Illumina human-6 v2.0 expression beadchip
Description
Purpose: The incidence of malignant melanoma is increasing worldwide in fair-skinned populations. Melanomas respond poorly to systemic therapy, and metastatic melanomas inevitably become fatal. Although spontaneous regression, likely due to immune defense activation, rarely occurs, we lack a biological rationale and predictive markers in selecting patients for immune therapy. Experimental Design: We performed unsupervised hierarchical clustering of global gene expression data from stage IV melanomas in 57 patients. For further characterization, we used immunohistochemistry of selected markers, genome-wide DNA copy number analysis, genetic and epigenetic analysis of the Q3 CDKN2A locus, and NRAS/BRAF mutation screening. Results: The analysis revealed four distinct subtypes with gene signatures characterized by expression of immune response, pigmentation differentiation, proliferation, or stromal composition genes. Although all subtypes harbored NRAS and BRAF mutations, there was a significant difference between subtypes (P < 0.01), with no BRAF/NRAS wild-type samples in the proliferative subtype. Additionally, the proliferative subtype was characterized by a high frequency of CDKN2A homozygous deletions (P < 0.01). We observed a different prognosis between the subtypes (P = 0.01), with a particularly poor survival for patients harboring tumors of the proliferative subtype compared with the others (P = 0.003). Importantly, the clinical relevance of the subtypes was validated in an independent cohort of 44 stage III and IV melanomas. Moreover, low expression of an a priori defined gene set associated with immune response signaling was significantly associated with poor outcome (P = 0.001). Conclusions: Our data reveal a biologically based taxonomy of malignant melanomas with prognostic effect and support an influence of the antitumoral immune response on outcome.
Publication Title
Gene expression profiling-based identification of molecular subtypes in stage IV melanomas with different clinical outcome.
Sample Metadata Fields
Sex, Specimen part
View Samples- Homo sapiens
- 22 Downloadable Samples
- Illumina human-6 v2.0 expression beadchip
Description
Purpose: The incidence of malignant melanoma is increasing worldwide in fair-skinned populations. Melanomas respond poorly to systemic therapy, and metastatic melanomas inevitably become fatal. Although spontaneous regression, likely due to immune defense activation, rarely occurs, we lack a biological rationale and predictive markers in selecting patients for immune therapy. Experimental Design: We performed unsupervised hierarchical clustering of global gene expression data from stage IV melanomas in 57 patients. For further characterization, we used immunohistochemistry of selected markers, genome-wide DNA copy number analysis, genetic and epigenetic analysis of the Q3 CDKN2A locus, and NRAS/BRAF mutation screening. Results: The analysis revealed four distinct subtypes with gene signatures characterized by expression of immune response, pigmentation differentiation, proliferation, or stromal composition genes. Although all subtypes harbored NRAS and BRAF mutations, there was a significant difference between subtypes (P < 0.01), with no BRAF/NRAS wild-type samples in the proliferative subtype. Additionally, the proliferative subtype was characterized by a high frequency of CDKN2A homozygous deletions (P < 0.01). We observed a different prognosis between the subtypes (P = 0.01), with a particularly poor survival for patients harboring tumors of the proliferative subtype compared with the others (P = 0.003). Importantly, the clinical relevance of the subtypes was validated in an independent cohort of 44 stage III and IV melanomas. Moreover, low expression of an a priori defined gene set associated with immune response signaling was significantly associated with poor outcome (P = 0.001). Conclusions: Our data reveal a biologically based taxonomy of malignant melanomas with prognostic effect and support an influence of the antitumoral immune response on outcome.
Publication Title
Gene expression profiling-based identification of molecular subtypes in stage IV melanomas with different clinical outcome.
Sample Metadata Fields
Sex, Specimen part
View Samples- Homo sapiens
- 29 Downloadable Samples
- Affymetrix Human Genome U133A 2.0 Array (hgu133a2)
Description
This sample is part of a study that compares small sample amplification technologies. The analysis looks at differential gene expression when compared to one round of T7 amplification. A tumor cell line was used in comparison to a human reference RNA in this study.
Publication Title
Big results from small samples: evaluation of amplification protocols for gene expression profiling.
Sample Metadata Fields
No sample metadata fields
View Samples