Microarray data from G2-synchronized p53(+) and p53(-) fibroblasts before and after 3 h release from cell cycle blockade in the presence of 5 M sodium arsenite.
Exit from arsenite-induced mitotic arrest is p53 dependent.
No sample metadata fields
View SamplesProstate cancer is the most commonly diagnosed malignancy in the United States. While the majority of cases are cured with radiation or surgery, about 1/3 of patients will develop metastatic disease which there is no cure, and has a life expectancy of less than 5 years. Identification of antigens associated with this transition to metastatic disease is crucial for future therapies. One such antigen of interest is the SSX gene family, which are cancer/testis antigens that are associated with the epithelial to mesenchymal transition in other cancer types. Prior work has shown that, in prostate cancer, SSX expression was restricted to metastatic tissue and not primary tumor tissue which may indicate a role in disease progression. Some work has been done into the function of the SSX family, which revealed transcriptional regulator activity. But neither the targets of this activity or the function of SSX are known. Through a transcriptomics approach, we are seeking a better understanding of the different genes and pathways SSX regulates in the context of prostate cancer, and to determine if these pathways may contribute to disease progression.
SSX2 regulates focal adhesion but does not drive the epithelial to mesenchymal transition in prostate cancer.
Cell line
View SamplesThe combined influence of oncogenic drivers, genomic instability, and/or DNA damage repair deficiencies increases replication stress in cancer. Cells with high replication stress rely on the upregulation of checkpoints like those governed by CHK1 for survival. Previous studies of the CHK1 inhibitor prexasertib demonstrated activity across multiple cancer types. Therefore, we sought to (1) identify markers of prexasertib sensitivity and (2) define the molecular mechanism(s) of intrinsic and acquired resistance using preclinical models representing multiple tumor types. Our findings indicate that while cyclin E dysregulation is a driving mechanism of prexasertib response, biomarkers associated with this aberration lack sufficient predictive power to render them clinically actionable for patient selection. Transcriptome analysis of a pan-cancer cell line panel and in vivo models revealed an association between expression of E2F target genes and prexasertib sensitivity and identified innate immunity genes associated with prexasertib resistance. Functional RNAi studies supported a causal role of replication fork components as modulators of prexasertib response. Mechanisms which protect cells from oncogene-induced replication stress may safeguard tumors from such stress induced by a CHK1 inhibitor, resulting in acquired drug resistance. Furthermore, resistance to prexasertib may be shaped by innate immunity.
A pan-cancer transcriptome analysis identifies replication fork and innate immunity genes as modifiers of response to the CHK1 inhibitor prexasertib.
Specimen part, Cell line
View SamplesWe performed NGS-based transcript profiling (RNA-seq) to profile transcripts that are expressed in MCF10A cells. 12,332 genes with FPKM>1 were considered as expressed in MCF10A cells. Overall design: mRNA profiles of MCF10A cells were generated by deep sequencing using Illumina Hiseq 2000.
Widespread genetic epistasis among cancer genes.
No sample metadata fields
View SamplesMultiple myeloma (MM), an incurable plasma cell malignancy, requires localisation within the bone marrow in order to survive and proliferate. Interactions between the malignant plasma cell and bone marrow mesenchymal stem cell (BMMSC) are thought to be a critical determinant of this requirement, and include both physical and chemical components. There is increasing evidence that the phenotype of the BMMSC is stably altered in patients with MM. More recently, it has been suggested that this phenotypic transformation is also observed in patients with the benign condition known as monoclonal gammopathy of undetermined significance (MGUS), which almost always precedes MM. In this study, we describe a mechanism by which the peptidyl arginine deiminase 2 (PADI2) enzyme plays an key role in the control of malignant plasma cell phenotype by BMMSCs. PADI enzymes deiminate (citrullinate) peptidyl arginine residues, changing the function or interactions made by the target protein. We identified PADI2 as one of the most highly upregulated transcripts in BMMSCs from both MGUS and MM patients, and that through citrullination of arginine residue 26 of histone H3, it induces the upregulation of interleukin-6 (IL-6) expression. This directly leads to the acquisition of resistance to the chemotherapeutic agent, bortezomib, by malignant plasma cells. We therefore describe a novel mechanism by which BMMSC dysfunction in patients with MGUS and MM directly leads to pro-malignancy signalling through the citrullination of histone H3R26.
Citrullination of histone H3 drives IL-6 production by bone marrow mesenchymal stem cells in MGUS and multiple myeloma.
Sex, Age, Specimen part, Disease, Disease stage
View SamplesContemporary treatment of pediatric acute myeloid leukemia (AML) requires the assignment of patients to specific risk groups. To explore whether expression profiling of leukemic blasts could accurately distinguish between the known risk groups of AML, we analyzed 130 pediatric and 20 adult AML diagnostic bone marrow or peripheral blood samples using the Affymetrix U133A microarray. Class discriminating genes were identified for each of the major prognostic subtypes of pediatric AML, including t(15;17)[PML-RARalpha], t(8;21)[AML1-ETO], inv(16) [CBFbeta-MYH11], MLL chimeric fusion genes, and cases classified as FAB-M7. When subsets of these genes were used in supervised learning algorithms, an overall classification accuracy of more than 93% was achieved. Moreover, we were able to use the expression signatures generated from the pediatric samples to accurately classify adult de novo AMLs with the same genetic lesions. The class discriminating genes also provided novel insights into the molecular pathobiology of these leukemias. Finally, using a combined pediatric data set of 130 AMLs and 137 acute lymphoblastic leukemias, we identified an expression signature for cases with MLL chimeric fusion genes irrespective of lineage. Surprisingly, AMLs containing partial tandem duplications of MLL failed to cluster with MLL chimeric fusion gene cases, suggesting a significant difference in their underlying mechanism of transformation. All the gene expression arrays are available through http://www.stjuderesearch.org/site/data/AML1/ in the original study (PMID:15226186). To study the RAS gene expression in the human AML patients, a total of 104 AML cases with known KRAS and NRAS status (including 72 gene expression arrays in the original study and 32 additional arrays acquired later on), as well as 4 CD34+ normal bone marrow cases deposited in GEO GSE33315, were including in this depository.
Dominant role of oncogene dosage and absence of tumor suppressor activity in Nras-driven hematopoietic transformation.
Disease, Disease stage
View SamplesIntroduction: Glioma stem cells isolated from human glioblastomas are resistant to radiation and cytotoxic chemotherapy and may drive tumor recurrence. Treatment efficacy may depend on the presence of glioma stem cells, expression of DNA repair enzymes such as methylguanine methyltransferase (MGMT), or transcriptome subtype. Methods: To model genetic alterations in the core signaling pathways of human glioblastoma, we induced conditional Rb knockout, Kras activation, and Pten deletion mutations in cortical murine astrocytes. Serial neurosphere culture, multi-lineage differentiation, and orthotopic transplantation were used to assess whether these mutations induced de-differentiation of cortical astrocytes into glioma stem cells. Efficacy of radiation and temozolomide was examined in vitro and in an allograft model in vivo. The effects of radiation on transcriptome subtype was examined by expression profiling. Results: G1/S-defective, Rb knockout astrocytes gained unlimited self-renewal and multi-lineage differentiation capacity, in both the presence and absence of Kras and Pten mutations. Only triple mutant astrocytes formed serially-transplantable glioblastoma allografts. Triple mutant astrocytes and allografts were sensitive to radiation, but expressed Mgmt and were resistant to temozolomide. Radiation induced a shift in transcriptome subtype of glioblastoma allografts from proneural to mesenchymal. Conclusion: A defined set of core signaling pathway mutations induces de-differentiation of cortical murine astrocytes into glioma stem cells. This non-germline genetically engineered mouse model mimics human proneural glioblastoma on histopathological, molecular, and treatment response levels. It may be useful in dissecting the genetic and cellular mechanisms of treatment resistance and developing more effective therapies. Overall design: Investigation of chromatin accessibility in astrocytes and glioblastoma cell lines
Core pathway mutations induce de-differentiation of murine astrocytes into glioblastoma stem cells that are sensitive to radiation but resistant to temozolomide.
Cell line, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Aneuploidy, oncogene amplification and epithelial to mesenchymal transition define spontaneous transformation of murine epithelial cells.
Sex, Specimen part
View SamplesHuman epithelial cancers are defined by a recurrent distribution of specific chromosomal aneuploidies. In our model system, mouse bladder and kidney epithelial cells spontaneously immortalize, transform and become tumorigenic after prolonged culture. We assessed genome and transcriptome alterations and found wide-spread aneuploidy, early transcriptional deregulation, and massive genomic dereguation of the cellular transcriptome.
Aneuploidy, oncogene amplification and epithelial to mesenchymal transition define spontaneous transformation of murine epithelial cells.
Sex, Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Trichostatin A enhances vascular repair by injected human endothelial progenitors through increasing the expression of TAL1-dependent genes.
Treatment
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