This study determined the genes that are differetially expressed when regulatory T cells were stimulated in vitro with IL-2
Selective IL-2 responsiveness of regulatory T cells through multiple intrinsic mechanisms supports the use of low-dose IL-2 therapy in type 1 diabetes.
Specimen part
View SamplesObjective: identify novel and relevant aspects of Sorafenib action on liver cancer cells. We found that in rat hepatocholangiocarcinoma (LCSC-2) cells, exposure to the MEK/multikinase inhibitor sorafenib did not inhibit ERK phosphorylation nor induced appreciable cell death in the low micromolar range; instead, the drug elicited a raise of intracellular reactive oxygen species (ROS) accompanied by a severe decrease of oxygen consumption and intracellular ATP levels, all changes consistent with mitochondrial damage. Moreover, Sorafenib induced depolarization of isolated rat liver mitochondria, indicating a possible direct effect on the organelle. Microarray analysis of gene expression in sorafenib-trated cells revealed a metabolic reprogramming toward aerobic glycolysis, that likely accounts for resitance to drug toxicity in this cell line. Importantly, cytotoxicity was strongly potentiated by glucose withdrawal from the culture medium or by the glycolytic inhibitor 2-deoxy-glucose, a finding also confirmed in the highly malignant melanoma cell line B16F10. Mechanistic studies revealed that ROS are pivotal to cell killing by the Sorafenib + 2DG combination, and that a low content of intracellular oxidants is associated with resistance to the drug; instead, Thr172phosphorylation/activation of the AMP-activated protein kinase (AMPK), induced by Sorafenib, may exert protective effects, since cytotoxicity was enhanced by an AMPK specific inhibitor and prevented by the AMPK activator Metformin. Overall, this study identifies novel and relevant aspects of Sorafenib action on liver cancer cells, including mitochondrial damage, induction of ROS and a metabolic cell reprogramming towards glucose addiction, potentially exploitable in therapy.
The multikinase inhibitor Sorafenib enhances glycolysis and synergizes with glycolysis blockade for cancer cell killing.
Specimen part, Cell line
View SamplesMedulloblastoma is the most frequent malignant pediatric brain tumor. Considerable efforts are dedicated to identify markers that help to refine treatment strategies. The activation of the Wnt/beta-catenin pathway occurs in 10-15% of medulloblastomas and has been recently described as a marker for favorable patient outcome. We report a series of 72 pediatric medulloblastomas evaluated for beta-catenin immunostaining, CTNNB1 mutations, and studied by comparative genomic hybridization. Gene expression profiles were also available in a subset of 40 cases. Immunostaining of beta-catenin showed extensive nuclear staining (>50% of the tumor cells) in 6 cases and focal nuclear staining (<10% of cells) in 3 cases. The other cases exhibited either a signal strictly limited to the cytoplasm (58 cases) or were negative (5 cases). CTNNB1 mutations were detected in all beta-catenin extensively nucleopositive cases. The expression profiles of these cases documented a strong activation of the Wnt/beta-catenin pathway. Remarkably, 5 out of these 6 tumors showed a complete loss of chromosome 6. In contrast, cases with focal nuclear beta-catenin staining, as well as tumors with negative or cytoplasmic staining, never demonstrated CTNNB1 mutation, Wnt/beta-catenin pathway activation or chromosome 6 loss. Patients with extensive nuclear staining were significantly older at diagnosis and were in continuous complete remission after a mean follow-up of 75.7 months (range 27.5-121.2) from diagnosis. All three patients with a focal nuclear staining of beta-catenin died within 36 months from diagnosis. Altogether, these data confirm and extend previous observations that CTNNB1-mutated tumors represent a distinct molecular subgroup of medulloblastomas with favorable outcome, indicating that therapy de-escalation should be considered. Yet, international consensus on the definition criteria of this distinct medulloblastoma subgroup should be achieved.
Beta-catenin status in paediatric medulloblastomas: correlation of immunohistochemical expression with mutational status, genetic profiles, and clinical characteristics.
No sample metadata fields
View SamplesPediatric medulloblastoma is considered a highly heterogeneous disease, and a new strategy of risk stratification to optimize therapeutic outcomes is required. We aimed to investigate a new risk-stratification approach based on expression profiles of medulloblastoma cohorts. We analyzed gene expression profiles of 30 primary medulloblastomas and detected strong evidence that poor survival outcome was significantly associated with mRNA expression profiles of 17p loss. However, it was not supported in independent cohorts from previously published data (n=100). We speculated that this controversy might come from complex conditions of two important prognostic determinants, loss of tumor suppressors (chromosome 17p) and high expression of oncogenes, c-myc (MYC) or N-myc (MYCN). Simultaneous consideration of these two factors led to a new subgrouping of patients, exhibiting obviously different survival expectancies between the subgroups. Patients with up-regulated WNT signalings were always pre-defined as an independent subgroup, which ultimately removed confounding effect arising from contradictory outcome, favorable prognosis of WNT medulloblastomas despite their high MYC/MYCN expression level. We also found that age is a significant prognostic marker after adjusting for 17p and MYC/MYCN status. Diminished survival in age <3 years was more substantial in groups with high expression of MYC/MYCN or 17p loss, indicating survival outcome might be coordinately affected by these three factors. We suggest a more tailored and easily applicable subgrouping system based on expression profiles of chromosome 17p and MYC/MYCN, while separating WNT medulloblastoma as an independent subgroup, which could provide the basis for a novel risk-stratification strategy in pediatric medulloblastoma.
Prognostic classification of pediatric medulloblastoma based on chromosome 17p loss, expression of MYCC and MYCN, and Wnt pathway activation.
Sex, Specimen part
View SamplesRhabdoid Tumors (RT) are highly aggressive tumors that are frequently localized in the central nervous system (CNS) where they are termed atypical teratoid and rhabdoid tumors (ATRT). We generated conditional Smarcb1-deficient mouse model leads to CNS Smarcb1-deficient tumors.
The occurrence of intracranial rhabdoid tumours in mice depends on temporal control of Smarcb1 inactivation.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
ATOH1 Promotes Leptomeningeal Dissemination and Metastasis of Sonic Hedgehog Subgroup Medulloblastomas.
Specimen part
View SamplesWe report findings that illuminate a dynamic metastasis pathway in the common pediatric brain tumor medulloblastoma.
ATOH1 Promotes Leptomeningeal Dissemination and Metastasis of Sonic Hedgehog Subgroup Medulloblastomas.
No sample metadata fields
View SamplesWe used microarrays to compare gene expression between shRNA targeting NRL and control replicates in D458Med cell line.
NRL and CRX Define Photoreceptor Identity and Reveal Subgroup-Specific Dependencies in Medulloblastoma.
Cell line
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 SamplesSuccessfully fighting infection requires a properly tuned immune system. Recent epidemiological studies link exposure to pollutants that bind the aryl hydrocarbon receptor (AHR) during development with poorer immune responses later in life. Yet, how developmental triggering of AHR durably alters immune cell function remains unknown. Using a mouse model, we show that developmental activation of AHR leads to long-lasting reduction in the response of CD8+ T cells during influenza virus infection, cells critical for resolving primary infection. Combining genome-wide approaches, we demonstrate that developmental activation alters DNA methylation and gene expression patterns in isolated CD8+ T cells prior to and during infection. Altered transcriptional profiles in CD8+ T cells from developmentally exposed mice reflect changes in pathways involved in proliferation and immunoregulation, with an overall pattern that bears hallmarks of T cell exhaustion. Developmental exposure also changed DNA methylation across the genome, but differences were most pronounced following infection, where we observed inverse correlation between promoter methylation and gene expression. This points to altered regulation of DNA methylation as one mechanism by which AHR causes durable changes in T cell function. Discovering that distinct gene sets and pathways were differentially changed in developmentally exposed mice prior to and after infection further reveals that the process of CD8+ T cell activation is rendered fundamentally different by early life AHR signaling. These findings reveal a novel role for AHR in the developing immune system: regulating DNA methylation and gene expression as immune cells respond to viral infection later in life. Overall design: In this study, two biological replicates were collected for each of four treatment groups: developmental exposure to vehicle control (Veh) and naïve, developmental exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and naïve, developmental exposure to Veh and infected, developmental exposure to TCDD and infected. For each sample, both RNA-seq and methylated DNA immunoprecipitation (MeDIP)-seq were performed.
Linking the aryl hydrocarbon receptor with altered DNA methylation patterns and developmentally induced aberrant antiviral CD8+ T cell responses.
No sample metadata fields
View Samples