The tumor microenvironment is characterized by low glucose and hypoxia. It is well known that changes in the tumor microenvironment, such as hypoxia and low glucose, can increase the production of VEGF. Although the role of hypoxia in the regulation of VEGF production is well understood, the mechanism linking glucose deprivation (GD) to tumor growth and angiogenesis is unclear. Here, GD (a physiological stimulus) was used to treat human tumor cells. The transcriptional reprogramming of tumor cells by GD was measured with microarray technology to provide a comprehensive analysis of the gene expression profile underlying the GD treatment. Our study suggested that GD initiates an angiogenic switch by increasing the expression of proangiogenic mediators (VEGF, FGF2, IL6, etc.) and decreasing the expression of angiogenesis inhibitors (THBS1, CXCL14 and CXCL10). The markers of Unfolded Protein Response (UPR) (Grp78/Bip, CHOP, ATF4, etc.) were significantly increased. The above results suggest GD may regulate angiogenesis through activation of the UPR.
The unfolded protein response induces the angiogenic switch in human tumor cells through the PERK/ATF4 pathway.
Specimen part, Cell line, Treatment
View SamplesThe majority of cancer patients do not respond to immunotherapy. In order to systematically discover pathways promoting cancer cell resistance to effector immune cells, we generated immunity-resistant Head and Neck Squamous Cell Carcinoma cell lines. We utilized RNA-Seq to determine what are the genes and pathways that are significantly altered when cancer cells become resistant to effectors. Overall design: RNA-Seq was performed on four cell lines, including two biologic replicates of wildtype and immune-resistant PCI-13 cells. The two immune-resistant PCI-13 cell lines were generated separately using the same protocol described in the manuscript.
Mitigating SOX2-potentiated Immune Escape of Head and Neck Squamous Cell Carcinoma with a STING-inducing Nanosatellite Vaccine.
Sex, Specimen part, Cell line, Subject
View SamplesChronic obstructive pulmonary disease (COPD), the fourth leading cause of death globally, is influenced by both cigarette smoking and genetic determinants. We have previously identified iron-responsive element binding protein 2 (IRP2) as a candidate COPD susceptibility gene based on genetic association studies, with IRP2 increased in the lungs of COPD patients. Here we demonstrate that mice deficient in IRP2 are protected from cigarette smoke (CS)-induced COPD. Using RIP-Seq, RNA-Seq, gene expression and pathway analysis, we identify IRP2 as a regulator of mitochondrial function in the lung. We show that an increase in IRP2 results in a cytochrome c oxidase (COX)-dependent alteration in oxidative capacity and mitochondrial-iron dysfunction involving frataxin. We demonstrate that mice with impaired COX or frataxin activity have altered responses to CS and show that overexpressing IRP2 in vivo alters mitochondrial dynamics. These data suggest a critical role of the mitochondria-iron axis in mediating the pathogenesis of COPD.
Mitochondrial iron chelation ameliorates cigarette smoke-induced bronchitis and emphysema in mice.
Sex, Specimen part
View SamplesObjective: Resident macrophages play an important role in atheromatous plaque rupture. The macrophage gene expression signature associated with plaque rupture is incompletely defined due to the complex cellular heterogeneity in the plaque. We aimed to characterise differential gene expression in resident plaque macrophages from ruptured and stable human atheromatous lesions. A cell-specific approach has the potential to address the question of gene expression differences between particular cell types in stable and unstable plaques with greater precision than approaches based on the study of whole plaques. Using laser micro-dissection, we isolated total RNA from macrophage-rich regions of stable and ruptured human atheromatous plaques derived from carotid endarterectomy samples which were comprehensively characterized using clinical, radiological and histological criteria, and carried out genome-wide gene expression profiling using microarrays.
Increased expression of fatty acid binding protein 4 and leptin in resident macrophages characterises atherosclerotic plaque rupture.
Sex, Age, Specimen part
View SamplesSeveral aspects common to a Western lifestyle, including obesity and decreased physical activity, are known risks for gastrointestinal cancers. There is an increasing amount of evidence suggesting that diet profoundly affects the composition of the intestinal microbiota. Moreover, there is now unequivocal evidence linking a dysbiotic gut to cancer development. Yet, the mechanisms through which high-fat diet (HFD)-mediated changes in the microbial community impact the severity of tumorigenesis in the gut, remain to be determined.
High-fat-diet-mediated dysbiosis promotes intestinal carcinogenesis independently of obesity.
Sex, Age, Specimen part, Treatment
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Integrative genomics identifies molecular alterations that challenge the linear model of melanoma progression.
Cell line
View SamplesThe two most common melanoma histopathologic subtypes, superficial spreading (SSM) and nodular melanoma (NM), are believed to represent sequential phases of linear progression from radial to vertical growth. Studies suggest, however, that SSM and NM are biologically distinct. We utilized an integrative genomic approach to examine the possibility that SSM and NM are the result of independent pathways characterized by unique molecular alterations. Cell lines including SSM, NM, metastatic melanoma, and melanocyte controls were evaluated for copy number changes and differential mRNA expression using single nucleotide polymorphism array (SNP 6.0, Affymetrix) and gene array (U133A 2.0, Affymetrix). Data sets were integrated to identify copy number alterations that correlated with gene expression, and array results were validated using immunohistochemistry on human tissue microarrays (TMAs) and an external data set. The functional effect of genomic deletion was assessed by lentiviral overexpression. Integrative genomics revealed 8 genes in which NM/SSM-specific copy number alterations were correlated with NM/SSM differential gene expression (P<0.05, Spearmans rank). Pathways analysis of differentially expressed genes (N=114) showed enrichment for metabolic-related processes. SSM-specific genomic deletions (DIS3, MTAP, G3BP2, SEC23IP, USO1) were verified in an expanded panel of cell lines, and forced overexpression of MTAP in SSM resulted in reduced cell growth. Metabolism-related gene ALDH7A1 was verified as overexpressed in NM using human TMAs.The identification of recurrent genomic deletions in SSM not present in NM challenges the linear model of melanoma progression and supports the unique molecular classification of SSM and NM.
Integrative genomics identifies molecular alterations that challenge the linear model of melanoma progression.
Cell line
View SamplesAlternative mRNA splicing is an important mechanism for regulation of gene expression. Changes in gene expression contribute to the pathogenesis of heart failure. However, changes in mRNA splicing have not been systematically examined in heart disease. We hypothesized that mRNA splicing is changed in diseased hearts.
Heart failure-associated changes in RNA splicing of sarcomere genes.
No sample metadata fields
View SamplesSynthetic DNA-binding proteins have found broad application in gene therapies and as tools for interrogating biology. Engineered proteins based on the CRISPR/Cas9 and TALE systems have been used to alter genomic DNA sequences, control transcription of endogenous genes, and modify epigenetic states. Although the activity of these proteins at their intended genomic target sites have been assessed, the genome-wide effects of their action have not been extensively characterized. Additionally, the role of chromatin structure in determining the binding of CRISPR/Cas9 and TALE proteins to their target sites and the regulation of nearby genes is poorly understood. Characterization of the activity these proteins using modern high-throughput genomic methods would provide valuable insight into the specificity and off-target effects of CRISPR- and TALE-based genome engineering tools. We have analyzed the genome-wide effects of TALE- and CRISPR-based transcriptional activators targeted to the promoters of two different endogenous human genes in HEK293T cells using a variety of high-throughput DNA sequencing methods. In particular, we assayed the DNA-binding specificity of these proteins and their effects on the epigenome. DNA-binding specificity was evaluated by ChIP-seq and RNA-seq was used to measure the specificity of these activators in perturbing the transcriptome. Additionally, DNase-seq was used to identify the chromatin state at target sites of the synthetic transcriptional activators and the genome-wide chromatin remodeling that occurs as a result of their action. Our results show that these genome engineering technologies are highly specific in both binding to their promoter target sites and inducing expression of downstream genes when multiple activators bind to a single promoter. Moreover, we show that these synthetic activators are able to induce the expression of silent genes in heterochromatic regions of the genome by opening regions of closed chromatin and decreasing DNA methylation. Interestingly, the transcriptional activation domain was not necessary for DNA-binding or chromatin remodeling in these regions, but was critical to inducing gene expression. This study shows that these CRISPR- and TALE-based transcriptional activators are exceptionally specific. Although we detected limited binding of off-target sites in the genome and changes to genome structure, these off-target event did not lead to any detectable changes in gene regulation. Collectively, these results underscore the potential for these technologies to make precise changes to gene expression for gene and cell therapies or fundamental studies of gene function. Overall design: HEK293T cells were transfected in triplicate with plasmids expressing synthetic transcription factors. The synthetic TFs were either (a) dCas9-VP64 fusion protein and a targeting guide RNA (gRNA), or (b) a TALE-VP64 fusion protein engineered to bind to a specific target site in the genome. As a control, cells were transfected with plasmids expressing GFP. After transfection, RNA-seq was used to identify both on-target and off-target binding sites for the synthetic TFs. The data in this submission were generated using the TALE transfection experiments.
Genome-wide specificity of DNA binding, gene regulation, and chromatin remodeling by TALE- and CRISPR/Cas9-based transcriptional activators.
No sample metadata fields
View SamplesPublished molecular profiling studies in patients with lymphoma suggested the influence of hypoxia inducible factor-1 alpha (HIF1) targets in prognosis of DLBCL. Yet, the role of hypoxia in hematological malignancies remains unclear. We observed that activation of HIF1 resulted in global translation repression during hypoxic stress in DLBCL. Protein translation efficiency as measured using 35S-labeled methionine incorporation revealed a 50% reduction in translation upon activation of HIF1. Importantly, translation was not completely inhibited and expression of clinically correlated hypoxia targets such as GLUT1, HK2, and CYT-C was found to be refractory to translational repression under hypoxia in DLBCL cells. Notably, hypoxic induction of these genes was not observed in normal primary B-cells. Translational repression was coupled with a decrease in mitochondrial function. Screening of primary DLBCL patient samples revealed that expression of HK2, which encodes for the enzyme hexokinase 2, was significantly correlated with DLBCL phenotype. Genetic knockdown studies demonstrated that HK2 is required for promoting growth of DLBCL under hypoxic stress. Altogether, our findings provide strong support for the direct contribution of HK2 in B-cell lymphoma development and suggest that HK2 is a key metabolic driver of the DLBCL phenotype.ne incorporation revealed a 50% reduction in translation upon activation of HIF1. Importantly, translation was not completely blunted and expression of clinically correlated hypoxia targets such as GLUT1, HK2, and CYT-C was found to be refractory to translational repression under hypoxia in DLBCL cells. Notably, hypoxic induction of these genes was not observed in normal primary B-cells. Translational repression was coupled with decrease in mitochondrial function. Screening of DLBCL patient samples identified that expression of HK2, which encodes for the enzyme hexokinase 2, was significantly correlated with DLBCL phenotype. Genetic knockdown studies show that HK2 is required for promoting growth of DLBCL under hypoxic stress. Altogether, our findings provide more definitive proof of direct contribution of HK2 in development of B-cell lymphoma and suggest that HK2 is a key metabolic driver of DLBCL phenotype.
Role of hypoxia in Diffuse Large B-cell Lymphoma: Metabolic repression and selective translation of HK2 facilitates development of DLBCL.
Cell line, Treatment
View Samples