Tumor cells exhibit aberrant metabolism characterized by high glycolysis even in the presence of oxygen. This metabolic reprogramming, known as the Warburg effect, provides tumor cells with the substrates and redox potential required for the generation of biomass. Here, we show that the mitochondrial NAD-dependent deacetylase SIRT3 is a crucial regulator of the Warburg effect. SIRT3 loss promotes a metabolic profile consistent with high glycolysis required for anabolic processes in vivo and in vitro. Mechanistically, SIRT3 mediates metabolic reprogramming independently of mitochondrial oxidative metabolism and through HIF1a, a transcription factor that controls expression of key glycolytic enzymes. SIRT3 loss increases reactive oxygen species production, resulting in enhanced HIF1a stabilization. Strikingly, SIRT3 is deleted in 40% of human breast cancers, and its loss correlates with the upregulation of HIF1a target genes. Finally, we find that SIRT3 overexpression directly represses the Warburg effect in breast cancer cells. In sum, we identify SIRT3 as a regulator of HIF1a and a suppressor of the Warburg effect.
SIRT3 opposes reprogramming of cancer cell metabolism through HIF1α destabilization.
Specimen part
View SamplesB cells are indispensable for humoral immunity, as they ultimately give rise to antibody-secreting plasma cells. During T cell-dependent antibody responses, naive B cells form germinal centers (GCs), a distinct histologic structure found in secondary lymphoid organs. Naive B cells become activated upon interaction with T cells and antigen presenting cells, and begin to rapidly proliferate and form the characteristic GC structure.
The LRF transcription factor regulates mature B cell development and the germinal center response in mice.
Age, Specimen part
View SamplesWe used microarrays to detail gene expression profile of several follicular lymphoma patient samples with different grades
Frequent disruption of the RB pathway in indolent follicular lymphoma suggests a new combination therapy.
Specimen part
View SamplesThe gene expression of mice with osteoblast-specific beta-catenin activation or FoxO1 deactivation are each compared to that of Wt.
Leukaemogenesis induced by an activating β-catenin mutation in osteoblasts.
Sex, Specimen part
View SamplesDNMT3A mutations are observed in myeloid malignancies, including myeloproliferative neoplasms (MPN), myelodysplastic syndromes (MDS), and acute myeloid leukemia (AML). Here we investigated the impact of conditional hematopoietic Dnmt3a loss on disease phenotype in primary mice. Dnmt3a ablation led to a lethal, fully penetrant myeloproliferative neoplasm with myelodysplasia (MDS/MPN) characterized by marked, progressive hepatomegaly that was transplantable. We detected expanded stem/progenitor populations in the liver of Dnmt3a-ablated mice. Homing studies showed that Dnmt3a-deleted bone marrow cells preferentially migrated to the liver. Hence, in addition to the established role of Dnmt3a in regulating self-renewal, Dnmt3a regulates tissue tropism and limits myeloid progenitor expansion in vivo. Overall design: Dnmt3af/f mice (Nguyen et al) were crossed into hematopoietic-specific inducible Mx1-Cre deletor line; we examined transcriptomes from FACS-sorted LSK and GMP populations from Dnmt3af/f Mx1-Cre+ (KO) and Dnmt3af/f Mx1-Cre- (CTRL) animals at 12 months of age
Dnmt3a regulates myeloproliferation and liver-specific expansion of hematopoietic stem and progenitor cells.
Specimen part, Cell line, Subject
View SamplesWe used microarrays to analyze the global gene expression and to identify the differentially expressed genes among wild type, prostate-specific Pten knockout, and prostate-specific Pten and Pml double knockout prostates at 12 weeks of age.
An aberrant SREBP-dependent lipogenic program promotes metastatic prostate cancer.
Specimen part
View SamplesThe translational control of oncoprotein expression is implicated in many cancers. Here we report an eIF4A/DDX2 RNA helicase-dependent mechanism of translational control that contributes to oncogenesis and underlies the anticancer effects of Silvestrol and related compounds. For example, eIF4A promotes T-ALL development in vivo and is required for leukaemia maintenance. Accordingly, inhibition of eIF4A with Silvestrol has powerful therapeutic effects in vitro and in vivo. We use transcriptome-scale ribosome footprinting to identify the hallmarks of eIF4A-dependent transcripts. These include 5'UTR sequences such as the 12-mer guanine quartet (CGG)4 motif that can form RNA G-quadruplex structures. Notably, among the most eIF4A-dependent and Silvestrol-sensitive transcripts are a number of oncogenes, super-enhancer associated transcription factors, and epigenetic regulators. Hence, the 5'UTRs of selected cancer genes harbour a targetable requirement for the eIF4A RNA helicase. Overall design: Comparison of ribosome-protected RNA for drug treated and DMSO treated KOPT-K1 cell, two replicates of ribosome-protected RNA sequencing and three replicates of RNA-seq.
RNA G-quadruplexes cause eIF4A-dependent oncogene translation in cancer.
No sample metadata fields
View SamplesMicroglial morphology is tightly associated with aspects of their functions during the postnatal stage. It is affected by not only intrinsic cues but also external factors.
Atypical Cadherin FAT3 Is a Novel Mediator for Morphological Changes of Microglia.
Treatment
View SamplesUnderstanding the underlying mechanisms of the well-established platelet hyporeactivity in neonates, would be of great relevance for both improving the clinical management of neonates, a population with a higher bleeding risk than adults (especially among sick and preterm infants), and getting new insights onto the regulatory mechanisms of platelet biology. Transcriptome analysis is a useful tool to identify mRNA signature affecting platelet function. However, human fetal/neonatal platelet transcriptome analysis has never been reported. Here, we used, for the first time, mRNA expression array to compare the platelet transcriptome changes during development. Microarray analysis was performed in pure platelet RNA obtained from adult and cord blood, using the same platform in two independent laboratories.
Comprehensive comparison of neonate and adult human platelet transcriptomes.
Specimen part
View SamplesCD133 (Prominin1) is pentaspan transmembrane glycoprotein expressed in several stem cell populations and cancers. Reactivity with an antibody (AC133) to a glycoslyated form of CD133 has been widely used for the enrichment of cells with tumor initiating activity in xenograph transplantation assays. We have found by fluorescence-activated cell sorting that increased AC133 reactivity in human embryonic stem cells, colon cancer and melanoma cells is correlated with increased DNA content and reciprocally, that the least reactive cells are in the G1/G0 portion of the cell cycle. Continued cultivation of cells sorted on the basis of high and low AC133 reactivity results in a normalization of the cell reactivity profiles indicating that cells with low AC133 reactivity can generate highly reactive cells as they resume proliferation. The association of AC133 with actively cycling cells may contribute to the basis for enrichment for tumor initiating activity.
Cell cycle-dependent variation of a CD133 epitope in human embryonic stem cell, colon cancer, and melanoma cell lines.
No sample metadata fields
View Samples