Genomic studies in acute myeloid leukemias (AML) have identified mutations which drive altered DNA methylation, including TET2 and IDH. Functional studies have shown these mutations contribute to transformation, although how these mutations impact the response to epigenetic therapies is not fully delineated. Here we show AMLs with TET2/IDH2 mutations combined with FLT3ITD mutations are specifically sensitive to 5-Azacytidine or to the IDH2 inhibitor AG-221, respectively. 5-Azacytidine/AG-221 therapies induced a reduction in leukemic blasts and in stem/progenitor expansion, with attenuation of aberrant DNA hypermethylation. These therapeutic benefits were achieved through restoration of differentiation, such that normalized hematopoiesis was derived from mutant cells. Consistent with these data, at the time of clinical response to 5-Azacytidine or AG-221, most patients had mutant-derived hematopoiesis. By contrast, combined AG-221/5-Azacytidine plus FLT3 inhibition reduced disease burden and reversed epigenetic dysfunction. Our studies suggest combined targeting of signaling and epigenetic pathways can increase therapeutic response in AML. Overall design: We profiled genome-wide transcription patterns of the hematopoietic stem cells (LSK) population in Wild-type, Idh2 R140Q Flt3-ITD, and Tet2-/-;Flt3-IDT mice. Idh2 R140Q Flt3-ITD mice with AML were treated with either vehicle or AG-221 (the first small molecule in vivo inhibitor of IDH2 to enter clinical trials). Tet2-/-;Flt3-IDT mice with AML were treated with vehicle or 5-Azacytidine (Decitabine, hypomethylating agent).
Combination Targeted Therapy to Disrupt Aberrant Oncogenic Signaling and Reverse Epigenetic Dysfunction in <i>IDH2</i>- and <i>TET2</i>-Mutant Acute Myeloid Leukemia.
Specimen part, Treatment, Subject
View SamplesThe growth of the mammalian ovarian follicle requires the formation of a fluid filled antrum, and maturation and differentiation of the ovarian granulosa cells, largely under the control of Follicle Stimulating Hormone (FSH). Many follicles will regress and die by a process called atresia at this early antral stage. We therefore decided to analyse the gene expression profiles of granulosa cells cultured in the presence or absence of FSH and Tumour Necrosis Factor-alpha (TNF), an apoptotic factor, to simulate the key influences. Different concentratons of FSH and TNFa in granulosa culture were used to determine effective conditions via estradiol and progesterone production, and cell number.
The global effect of follicle-stimulating hormone and tumour necrosis factor α on gene expression in cultured bovine ovarian granulosa cells.
Specimen part, Treatment
View SamplesGene expression of mouse hepatoblasts (HBs) expressing IDH1 WT, IDH1 R132C, IDH2 WT, R172K and empty vector controls (N=2 cultures for each condition) grown on collagen-coated plates and IDH1 R132C and empty vector controls on uncoated plates were evaluated using Affymetrix Mouse 430Av2 DNA microarrays that were processed at the Dana-Farber Cancer Institute core facility (http://macf-web.dfci.harvard.edu/) using their standard protocol.
Mutant IDH inhibits HNF-4α to block hepatocyte differentiation and promote biliary cancer.
Specimen part
View SamplesBone morphogenetic proteins (BMP) are firmly implicated as intra-ovarian regulators of follicle development and steroidogenesis. We carried out a microarray analysis to examine global changes in gene expression in bovine theca cells in response to treatment with BMP6 alone and in combination with LH. There was a major effect of BMP6 treatment on the gene expression profile with a much weaker effect of LH. None of these differences in response to LH treatment was found to be statistically significant after applying Benjamini-Hochberg correction. BMP6 significantly (>2-fold; P<0.01) up- or down-regulated expression of 445 genes. Insulin-like peptide 3 (INSL3) was the most heavily down-regulated gene (-43-fold) with CYP17A1 and other key transcripts involved in TC steroidogenesis including LHCGR, INHA, STAR, CYP11A1 and HSD3B1 also down-regulated. BMP6 also reduced expression of NR5A1 encoding steroidogenic factor-1 known to target the promoter regions of the aforementioned genes. Real-time PCR confirmed these findings and also revealed a marked reduction in expression of INSL3 receptor (RXFP2). Secretion of INSL3 protein and androstenedione were also suppressed suggesting a functional link between BMP and INSL3 pathways in controlling androgen synthesis.
Functional link between bone morphogenetic proteins and insulin-like peptide 3 signaling in modulating ovarian androgen production.
Specimen part
View SamplesMutations in isocitrate dehydrogenase 1 and 2 (IDH1/2) have been discovered in several cancer types and cause the neurometabolic syndrome D2-Hydroxyglutaric aciduria (D2HGA). The mutant enzymes exhibit neomorphic activity resulting in production of D2- hydroxyglutaric acid (D-2HG). To study the pathophysiological consequences of the accumulation of D2-HG, we generated transgenic mice with conditionally activated IDH2R140Q and IDH2R172K alleles. Global induction of mutant IDH2 expression in adults resulted in dilated cardiomyopathy, white matter abnormalities throughout the central nervous system (CNS), and muscular dystrophy. Embryonic activation of mutant IDH2 resulted in more pronounced phenotypes, including runting, hydrocephalus, and shortened life spanrecapitulating the abnormalities observed in D2HGA patients. The diseased hearts exhibited mitochondrial damage and glycogen accumulation with a concordant upregulation of genes involved in glycogen biosynthesis. Notably, mild cardiac hypertrophy was also observed in nude mice implanted with IDH2R140Q expressing xenografts, suggesting that 2HG may potentially act in a paracrine fashion. Finally, we show that silencing of IDH2R140Q in mice with an inducible transgene restores heart function by lowering 2HG levels. Together, these findings indicate that inhibitors of mutant IDH2 may be beneficial in the treatment of D2HGA and suggest that 2HG produced by IDH mutant tumors has the potential to provoke a paraneoplastic condition.
D-2-hydroxyglutarate produced by mutant IDH2 causes cardiomyopathy and neurodegeneration in mice.
Specimen part
View SamplesNaturally occurring FoxP3+CD4+CD25+high regulatory T cells (Tregs) play an important role in dominant tolerance, suppressing auto-reactive CD4+CD25- T cell activity. Although Tregs from T1D subjects are functionally deficient, there is little knowledge of the molecular mechanisms that orchestrate this loss of Treg function. We observed increased apoptosis (by a novel YOPRO-1/7AAD dual staining protocol) and decreased suppression in polyclonal Tregs in the periphery from high at-risk and T1D subjects. We hypothesize that prior to and during the onset of disease, Tregs lack pro-survival signals and are caught up in a relatively deficient cytokine milieu whose effects may be detectable in the periphery.
Apoptosis of CD4+ CD25(high) T cells in type 1 diabetes may be partially mediated by IL-2 deprivation.
Sex, Age, Race
View SamplesXBP1 is the transcriptino factor that is activated by the ER stress. XBP1 is known to induce the ER dexpansion and increase the expression of the ER chaperone genes to prtect the cell from the ER stress. We generated a mouse strain that lacked XBP1 specifically in the mouse intestine by breeding the XBP1flox mice with Villin-cre mice. Here we examined genes that are differentially expressed between WT and XBP1 KO mouse intestine to identify genes that are downstream of XBP1.
XBP1 links ER stress to intestinal inflammation and confers genetic risk for human inflammatory bowel disease.
No sample metadata fields
View SamplesTo examine the effect of seminal fluid on the whole genome expression profile of endometrial tissue following mating, RNA was extracted from endometrial tissue collected 8 h after CBAF1 females were mated with intact Balb/c males and compared to RNA from endometrial tissue of females mated with seminal fluid deficient SVX/VAS Balb/c males. This comparison controlled for ovarian hormone status, exposure to the male and mating activity, and the neuroendocrine response to cervical and vaginal stimulus at mating, so that changes in endometrial gene expression could be attributed specifically to contact with seminal fluid. The endometrial RNA from n=16 individual females was pooled into four independent biological replicates per treatment group (n=4 endometrial samples per replicate) and expression profiles were analyzed by Affymetrix microarray. Seminal fluid exposure induced a clear difference in the profile of genes expressed in the endometrium with a total of 335 genes were differentially regulated with a fold-change greater than 1.5 and p<0.05. Of these, 190 genes were upregulated and 145 genes were downregulated following contact with seminal fluid. Bioinformatics analysis revealed TLR4 signaling as a strongly predicted upstream regulator activated by the differentially expressed genes.Additional experiments confirmed the role of TLR4 with the absence of TLR4 in TLR4 null mice resulting in a failure for seminal fluid to induce endometrial Csf3, Cxcl2, Il6 and Tnf expression. This study provides evidence that TLR4 contributes to seminal fluid modulation of the periconception immune environment. Activation of TLR4 signaling by microbial or endogenous components of seminal fluid is thus implicated as a key element of the female tract response to seminal fluid at the outset of pregnancy in mice.
TLR4 Signaling Is a Major Mediator of the Female Tract Response to Seminal Fluid in Mice.
Sex, Specimen part, Time
View SamplesNeuronal function critically depends on coordinated subcellular distribution of mRNAs. Disturbed mRNA processing and axonal transport has been found in spinal muscular atrophy and could be causative for dysfunction and degeneration of motoneurons. Despite the advances made in characterizing the transport mechanisms of several axonal mRNAs, an unbiased approach to identify the axonal repertoire of mRNAs in healthy and degenerating motoneurons has been lacking. Here we used compartmentalized microfluidic chambers to investigate the somatodendritic and axonal mRNA content of cultured motoneurons by microarray analysis. In axons, transcripts related to protein synthesis and energy production were enriched relative to the somatodendritic compartment. Knockdown of Smn, the protein deficient in spinal muscular atrophy, produced a large number of transcript alterations in both compartments. Transcripts related to immune functions, including MHC class I genes, and with roles in RNA splicing were upregulated in the somatodendritic compartment. On the axonal side, transcripts associated with axon growth and synaptic activity were downregulated. These alterations provide evidence that subcellular localization of transcripts with axonal functions as well as regulation of specific transcripts with nonautonomous functions is disturbed in Smn-deficient motoneurons, most likely contributing to the pathophysiology of spinal muscular atrophy.
Subcellular transcriptome alterations in a cell culture model of spinal muscular atrophy point to widespread defects in axonal growth and presynaptic differentiation.
Specimen part
View SamplesCell based bone regeneration strategies offer promise for traumatic bone injuries, congenital defects, non-union fractures and other skeletal pathologies. Postnatal bone remodeling and fracture healing provide evidence that an osteochondroprogenitor cell is present in adult life which can differentiate to remodel or repair the fractured bone. However, cell based skeletal repair in the clinic is still in its infancy mostly due to poor characterization of progenitor cells and lack of knowledge about their in vivo behavior. Here we took a combined approach of high throughput screening, flow based cell sorting and in vivo transplantation to identify markers that identify osteochondroprogenitor cells. We show that the presence of tetraspanin CD9 enriches for osteochondroprogenitors within CD105+vemesenchymal cells and these cells readily form bone upon transplantation. In addition we have used Thy1.2 (CD90) and the ectonucleotidase CD73 to identify subsets within the CD9+ve population that lead to endochondral or intramembranous-like bone formation. Utilization of this unique cell surface phenotype to enrich for osteochondroprogenitor cells will allow for further characterization of the molecular mechanisms that regulate their osteogenic properties.
Tetraspanin CD9 and ectonucleotidase CD73 identify an osteochondroprogenitor population with elevated osteogenic properties.
No sample metadata fields
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