In order to investigate the function of Bach2 in pre-B ALL, we isolated bone marrow cells from wildtype and Bach2 knockout mice of C57Bl6 background and transformed them with BCR-ABL1.
Mechanistic rationale for targeting the unfolded protein response in pre-B acute lymphoblastic leukemia.
Age, Specimen part, Disease, Disease stage, Treatment
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Mechanistic rationale for targeting the unfolded protein response in pre-B acute lymphoblastic leukemia.
Specimen part
View SamplesThe plasma cell transcription factor XBP1 is critical for terminal differentiation of B cells into plasma cells but has no known role at earlier stages of B-cell development. Here we show that XBP1 is not only important during early B-cell development and for survival of pre-B cells but also protects pre-B ALL cells. Among pre-B ALL subset, XBP1 was hypomethylated and highest expressed in the Ph+ ALL subset. Cre-mediated deletion of XBP1 in a mouse model of Ph+ ALL compromised proliferation and viability and prolonged survival of leukemia-bearing mice. Interestingly, XBP1 expression levels were positively transcriptionally regulated by STAT5 and negatively by BACH2 and BCL6. High XBP1 expression in high risk ALL patients at the time of diagnosis predicted poor outcome in two clinical trials. Clinically, small-molecule inhibition of IRE1-dependent XBP1-activation caused cell death of patient-derived pre-B ALL cells and affected leukemia-initiation in transplant recipient mice. Collectively, these studies identify XBP1 as an important survival factor and as a potential therapeutic target to overcome drug-resistance in pre-B ALL. Overall design: Genome-wide profiling of mRNA levels in p210 transduced murine Xbp1 fl/+ pre-B cells with ERT2 (XE.1,2,3) and Cre- ERT2 Â (XC.1,2,3).
Mechanistic rationale for targeting the unfolded protein response in pre-B acute lymphoblastic leukemia.
No sample metadata fields
View SamplesThe plasma cell transcription factor XBP1 is critical for terminal differentiation of B cells into plasma cells but has no known role at earlier stages of B-cell development. Here we show that XBP1 is not only important during early B-cell development and for survival of pre-B cells but also protects pre-B ALL cells. Among pre-B ALL subset, XBP1 was hypomethylated and highest expressed in the Ph+ ALL subset. Cre-mediated deletion of XBP1 in a mouse model of Ph+ ALL compromised proliferation and viability and prolonged survival of leukemia-bearing mice. Interestingly, XBP1 expression levels were positively transcriptionally regulated by STAT5 and negatively by BACH2 and BCL6. High XBP1 expression in high risk ALL patients at the time of diagnosis predicted poor outcome in two clinical trials. Clinically, small-molecule inhibition of IRE1-dependent XBP1-activation caused cell death of patient-derived pre-B ALL cells and affected leukemia-initiation in transplant recipient mice. Collectively, these studies identify XBP1 as an important survival factor and as a potential therapeutic target to overcome drug-resistance in pre-B ALL.
Mechanistic rationale for targeting the unfolded protein response in pre-B acute lymphoblastic leukemia.
Specimen part
View SamplesEupolauridine and liriodenine are plant-derived aporphinoid alkaloids that exhibit potent inhibitory activity against the opportunistic fungal pathogens Candida albicans and Cryptococcus neoformans. However, the molecular mechanism of this antifungal activity is unknown. In this study, we show that eupolauridine 9591 (E9591), a synthetic analog of eupolauridine, and liriodenine methiodide (LMT), a methiodide salt of liriodenine, mediate their antifungal activities by disrupting mitochondrial iron-sulfur (Fe-S) cluster synthesis. Several lines of evidence supported this conclusion. First, both E9591 and LMT elicited a transcriptional response indicative of iron imbalance, causing the induction of genes that are required for iron uptake and for the maintenance of cellular iron homeostasis. Second, a genome-wide fitness profile analysis showed that yeast mutants with deletions in iron homeostasisrelated genes were hypersensitive to E9591 and LMT. Third, treatment of wild-type yeast cells with E9591 or LMT generated cellular defects that mimicked deficiencies in mitochondrial Fe-S cluster synthesis, including an increase in mitochondrial iron levels, a decrease in the activities of Fe-S cluster enzymes, a decrease in respiratory function, and an increase in oxidative stress. Collectively, our results demonstrate that E9591 and LMT perturb mitochondrial Fe-S cluster biosynthesis; thus, these two compounds target a cellular pathway that is distinct from the pathways commonly targeted by clinically used antifungal drugs. Therefore, the identification of this pathway as a target for antifungal compounds has potential applications in the development of new antifungal therapies.
Two plant-derived aporphinoid alkaloids exert their antifungal activity by disrupting mitochondrial iron-sulfur cluster biosynthesis.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
BRAFV600E remodels the melanocyte transcriptome and induces BANCR to regulate melanoma cell migration.
Specimen part, Cell line
View SamplesMost cancer genomics papers to date have focused on aberrations in genomic DNA and protein-coding transcripts. However, around 50% of transcripts have no coding potential and may exist as non-coding RNA. We performed RNA-seq in BRAFv600e melanoma skin cancer and on melanocytes over-expressing oncogenic BRAF to catalog transcriptome remodeling. We discovered that BRAF regulates expression of 1027 protein coding transcripts, 39 annotated lncRNAs and 70 novel transcripts. Many of the novel transcripts are lncRNAs. We used an indepenedent dataset to interrogate our novel transcripts and found that the novel lncRNA BANCR is a BRAF-regulated lncRNA recurrently upregulated in melanoma. Knockdown of BANCR impairs melanoma cell migration.
BRAFV600E remodels the melanocyte transcriptome and induces BANCR to regulate melanoma cell migration.
Cell line
View SamplesComparison of gene expression in intestinal epithelial cells in the presence or absence of ectopic induction of MSI2 in vivo
Transformation of the intestinal epithelium by the MSI2 RNA-binding protein.
Specimen part
View SamplesHematopoietic stem and progenitor cells (Lineagelo ScaI+ c-Kit+) were sorted 4 weeks post pIpC injection. RNA was extracted using TRIZOL and RNEASY RNA extraction kit. RNA was then amplified using NUGEN Pico amplification kit, fragmented and hybridized on Mouse Expression Array 430 2.0. Signal normalization was performed by RMA method. Data were analyzed using GSEA across the complete list of genes ranked by signal-to-noise ratio.
Musashi-2 controls cell fate, lineage bias, and TGF-β signaling in HSCs.
Specimen part
View SamplesLeukemia stem cells (LSCs) are found in most aggressive myeloid diseases and contribute to therapeutic resistance. Genetic and epigenetic alterations cause a dysregulated developmental program in leukemia. The MSI2 RNA binding protein has been previously shown to predict poor survival in leukemia. We demonstrate that the conditional deletion of Msi2 results in delayed leukemogenesis, reduced disease burden and a loss of LSC function. Gene expression profiling of the Msi2 ablated LSCs demonstrates a loss of the HSC/LSC and an increase in the differentiation program. The gene signature from the Msi2 deleted LSCs correlates with survival in AML patients. MSI2’s maintains the MLL self-renewal program by interacting with and retaining efficient translation of Hoxa9, Myc and Ikzf2. We further demonstrate that shRNA depletion of the MLL target gene Ikzf2 also contributes to MLL leukemia cell survival. Our data provides evidence that MSI2 controls efficient translation of the oncogenic LSC self-renewal program and a rationale for clinically targeting MSI2 in myeloid leukemia. Overall design: RNA-Seq was performed on sorted c-Kit high leukemic cells from 2 Msi2 -/- and 2 Msi2 f/f mice.
Musashi2 sustains the mixed-lineage leukemia-driven stem cell regulatory program.
No sample metadata fields
View Samples