This SuperSeries is composed of the SubSeries listed below.
Preclinical activity of LBH589 alone or in combination with chemotherapy in a xenogeneic mouse model of human acute lymphoblastic leukemia.
Sex, Specimen part, Cell line
View SamplesHistone deacetylases (HDACs) have been identified as therapeutic targets due to regulatory function in DNA structure and organization. We have analyzed the role of the LBH589, a novel pan inhibitor of class I and II HDACs, in Acute Lymphoblastic Leukemia. In vitro, LBH589 was shown to induce a dose dependent antiproliferative and apoptotic effect which was associated with an increase in the acetylation of H3 and H4 histone acetylation which was uniformly in every genetic subgroup of ALL. In vivo administration of LBH589 in BALB/c-RAG2-/-c-/- mice in which T and B-cell leukemic cell lines were injected induced a significant reduction in tumor growth (TOM-1, p<0.01 and MOLT-4 p<0.05). Leukemic cells from patients were employed to establish a xenograft model of human leukemia in BALB/c-RAG2-/-c-/- mice and further transplanted in consecutive generations of mice. Treatment of these xenografts with LBH589 induced an increase in the acetylation of H3 and H4 and prolonged the survival of mice in comparison with the animals treated with Vincristine and Dexametasone (p<0.05) and this effect was significantly higher when LBH589 was combined with Vincristine and Dexametasone (p<0.001). Our results that the use of LBH589 in combination with standard chemotherapy represents an attractive option for treatment of patients with ALL.
Preclinical activity of LBH589 alone or in combination with chemotherapy in a xenogeneic mouse model of human acute lymphoblastic leukemia.
Cell line
View SamplesThe Myc proteins (N-, L- and c-Myc) are transcription factors involved in many biological functions such as regulation of cell proliferation, differentiation, metabolism and apoptosis. A large number of human cancers show enhanced expression of myc family proto-oncogenes as one of their hallmarks. These proteins contain a basic region/helix-loop-helix/leucine zipper (bHLHZip) domain that mediates DNA binding and heterodimerization with its partner Max (Myc/Max heterodimer). Among Myc proteins, c-Myc is the most widely expressed and relevant in primary B lymphocytes. Some reports have implied that c-Myc can perform some functions without Max in different cell contexts. However, the functional interplay in vivo between c-Myc and Max during B lymphocyte differentiation is not well-known. Here we show that c-Myc requires Max. However, key biological processes such as cell differentiation and DNA replication can initially progress without c-Myc/Max heterodimer in primary B lymphocytes. We found that B lymphocytes lacking Myc, Max or both showed upregulation of signalling pathways associated with the B cell receptor. Our data suggest that c-Myc/Max heterodimers are not essential for the initiation of certain biological processes in B lymphocytes. Rather, c-Myc/Max are necessary for fine-tuning the initial response in these cells after activation. Overall design: B cell mRNA profiles of 8-week old control (HET) Myc deficient (MycKO), Max deficient (MaxKO) and double deficient (DKO) mice were generated by deep sequencing, in duplicate, using a HiSeq2500 (Illumina.
Functional interplay between c-Myc and Max in B lymphocyte differentiation.
Age, Specimen part, Subject
View SamplesPolycomb repressive complexes (PRCs) are important chromatin regulators of ES cell function. RYBP binds Polycomb H2A monoubiquitin ligases Ring1A and Ring1B, and has been suggested to participate in localizing Polycomb complexes to their targets. Moreover, constitutive inactivation of RYBP precludes ES cell formation. Here we have used ES cells conditionally deficient in RYBP to investigate RYBP function. Chromosome immunoprecipitation on a chip (ChIP-chip) of RYBP and microarray experiments were performed using wild type and knocked-out ES cells.
RYBP represses endogenous retroviruses and preimplantation- and germ line-specific genes in mouse embryonic stem cells.
Specimen part, Disease
View SamplesWe used microarrays to investigate a global change in gene expression by conditional depletion of Rybp in mouse ES cells.
RYBP represses endogenous retroviruses and preimplantation- and germ line-specific genes in mouse embryonic stem cells.
Specimen part
View SamplesGene expression change by Yaf2 KD in wild type or RYBP KO ES cells.
RYBP represses endogenous retroviruses and preimplantation- and germ line-specific genes in mouse embryonic stem cells.
Specimen part
View SamplesDemethyl fructiculin A is a diterpenoid quinone component of the exudates from Salvia corrugata (SCO-1) leafes. SCO-1 was recently reported to induce anoikis in mammalian cell lines via a molecular mechanism involving the presence of the membrane scavenging receptor CD36. However, experiments performed with cells lacking CD36, showed that SCO-1 was able to induce apoptosis also via alternate pathways. To contribute to a better characterization of the molecular mechanisms underlining the cytotoxic activity of SCO-1, we decided to pursue an unbiased pharmacogenomic approach by generating the gene expression profile of GBM TICs subjected to the administration of SCO-1 and comparing it with that of control cells exposed to the solvent. With this strategy we hypothesized to highlight those pathways and biological processes unlashed by SCO-1.
Demethyl fruticulin A (SCO-1) causes apoptosis by inducing reactive oxygen species in mitochondria.
Time
View SamplesNeuroblastoma (NB) is a neoplasm of the sympathetic nervous system, and is the most common solid tumor of infancy. NBs are very heterogeneous, with a clinical course ranging from spontaneous regression to resistance to all current forms of treatment. High-risk patients need intense chemotherapy, and only 30-40% will be cured. Relapsed or metastatic tumors acquire multi-drug resistance, raising the need for alternative treatments. Owing to the diverse mechanisms that are responsible of NB chemoresistance, we aimed to target epigenetic factors that control multiple pathways to bypass therapy resistance. We found that the SWI/SNF-related, matrix-associated, actin- dependent regulator of chromatin, subfamily a, member 4 (SMARCA4/BRG1) was consistently upregulated in advanced stages of NB, with high BRG1 levels being indicative of poor outcome. Loss-of-function experiments in vitro and in vivo showed that BRG1 is essential for the proliferation of NB cells. Furthermore, whole genome transcriptome analysis revealed that BRG1 controls the expression of key elements of oncogenic pathways such as PI3K/AKT and BCL2, which offers a promising new combination therapy for high-risk NB
BRG1/SMARCA4 is essential for neuroblastoma cell viability through modulation of cell death and survival pathways.
Cell line
View SamplesAnalysis of the expression profiles of MCF7 cells transduced with a control shRNA and an TSC2-targeted shRNA (leading to tuberin depletion).
Lymphangioleiomyomatosis Biomarkers Linked to Lung Metastatic Potential and Cell Stemness.
Cell line
View SamplesPlant cells contain different O-acetylserine(thiol)lyase (OASTL) enzymes involved in Cys biosynthesis and located in different subcellular compartments. These enzymes are made up of a complex variety of isoforms resulting in different subcellular Cys pools. To unravel the contribution of cytosolic Cys to plant metabolism, we characterized the knockout oas-a1.1 and osa-a1.2 mutants, deficient in the most abundant cytosolic OASTL isoform in Arabidposis thaliana. Total intracellular Cys and glutathione concentrations were reduced, and the glutathione redox state was shifted in favour of its oxidized form. Interestingly, the capability of the mutants to chelate heavy metals did not differ from that of the wild type, but the mutants have an enhanced sensitivity to Cd. With the aim of establishing the metabolic network most influenced by the cytosolic Cys pool, we used the ATH1 GeneChip for evaluation of differentially expressed genes in the oas-a1.1 mutant grown under non-stress conditions. The transcriptomic footprints of mutant plants had predicted functions associated with various physiological responses that are dependent on reactive oxygen species and suggested that the mutant was oxidatively stressed. To further elucidate the specific function(s) of the OAS-A1 isoform in the adaptation response to cadmium we extended the trasncriptome experiment to the wild type and oas-a1.1 mutant plants exposed to Cd. The comparison of transcriptomic profiles showed a higher proportion of genes with altered expression in the mutant than in the wild type, highlighting up-regulated genes identified as of the general oxidative stress response rather than metal-responsive genes.
Knocking out cytosolic cysteine synthesis compromises the antioxidant capacity of the cytosol to maintain discrete concentrations of hydrogen peroxide in Arabidopsis.
Specimen part
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