Most human tumors have abnormal numbers of chromosomes, a condition known as aneuploidy. The mitotic checkpoint is an important mechanism that prevents aneuploidy through restraining the activity of the anaphase-promoting complex (APC). USP44 was identified as a key regulator of APC activation that maintains the association of MAD2 with the APC co-activator Cdc20. However, the physiological importance of USP44 and its impact on cancer biology are unknown. Here, we show that USP44 is required to prevent tumors in mice and is frequently down-regulated in human lung cancer. USP44 inhibits chromosome segregation errors independently of its role in the mitotic checkpoint by regulating proper centrosome separation, positioning, and mitotic spindle geometry, functions that require direct binding to the centriole protein, centrin. These data reveal a new role for the ubiquitin system in mitotic spindle regulation and underscore the importance of USP44 in the pathogenesis of human cancer.
USP44 regulates centrosome positioning to prevent aneuploidy and suppress tumorigenesis.
Sex, Disease, Disease stage
View SamplesWe identify genes presenting a specific expression profile in midgut carcinoid cells, primary carcinoids tumors and liver metastasis were gene profiled.
Novel markers for enterochromaffin cells and gastrointestinal neuroendocrine carcinomas.
Specimen part
View SamplesPDGF and FGF treatment in E13.5 MEPMs. 4 hr PDGF treated MEPMs (3 replicates), 4 hr FGF treated MEPMs (3 replicates), 1 hr PDGF + PD325901 treated MEPMs (2 replicates), 4 hr PDGF + PD325901 treated MEPMs (2 replicates), 1 hr FGF + PD325901 treated MEPMs (2 replicates), 4 hr FGF + PD325901 treated MEPMs (2 replicates), 1 hr PDGF + LY294002 treated MEPMs (2 replicates), 4 hr PDGF + LY294002 treated MEPMs (2 replicates), 1 hr FGF + LY294002 treated MEPMs (2 replicates), 4 hr FGF + LY294002 treated MEPMs (2 replicates) Overall design: 4 hr PDGF treated MEPMs (3 replicates), 4 hr FGF treated MEPMs (3 replicates), 1 hr PDGF + PD325901 treated MEPMs (2 replicates), 4 hr PDGF + PD325901 treated MEPMs (2 replicates), 1 hr FGF + PD325901 treated MEPMs (2 replicates), 4 hr FGF + PD325901 treated MEPMs (2 replicates), 1 hr PDGF + LY294002 treated MEPMs (2 replicates), 4 hr PDGF + LY294002 treated MEPMs (2 replicates), 1 hr FGF + LY294002 treated MEPMs (2 replicates), 4 hr FGF + LY294002 treated MEPMs (2 replicates)
Receptor tyrosine kinases modulate distinct transcriptional programs by differential usage of intracellular pathways.
No sample metadata fields
View SamplesReceptor tyrosine kinase signaling is critical for mammalian craniofacial development, but the key downstream transcriptional effectors remain unknown. We demonstrate that SRF is induced by both PDGF and FGF signaling in mouse embryonic palatal mesenchyme cells, and Srf neural crest conditional mutants exhibit facial clefting accompanied by proliferation and migration defects. Srf and Pdgfra mutants interact genetically in craniofacial development, but Srf and Fgfr1 mutants do not. This signal specificity is recapitulated at the level of cofactor activation: while both PDGF and FGF target gene promoters show enriched genome-wide overlap with SRF ChIP-seq peaks, PDGF selectively activates a network of MRTF-dependent cytoskeletal genes. Collectively, our results identify a novel role for SRF in proliferation and migration during craniofacial development and delineate a mechanism of receptor tyrosine kinase specificity mediated through differential cofactor usage, leading to a unique PDGF-responsive SRF-driven transcriptional program in the midface. Overall design: Serum Starved MEPMs (4 replicates), 1 hr PDGF treated MEPMs (4 replicates), 1 hr FGF treated MEPMs (3 replicates)
Receptor tyrosine kinases modulate distinct transcriptional programs by differential usage of intracellular pathways.
No sample metadata fields
View SamplesQuiescent and dividing hemopoietic stem cells (HSC) display marked differences in their ability to move between the peripheral circulation and the bone marrow. Specifically, long-term engraftment potential predominantly resides in the quiescent HSC subfraction, and G-CSF mobilization results in the preferential accumulation of quiescent HSC in the periphery. In contrast, stem cells from chronic myeloid leukemia (CML) patients display a constitutive presence in the circulation. To understand the molecular basis for this, we have used microarray technology to analyze the transcriptional differences between dividing and quiescent, normal, and CML-derived CD34+ cells.
Transcriptional analysis of quiescent and proliferating CD34+ human hemopoietic cells from normal and chronic myeloid leukemia sources.
Specimen part, Disease, Subject
View SamplesAn unbalanced karyotype, a condition known as aneuploidy, has a profound impact on cellular physiology and is a hallmark of cancer. Determining how aneuploidy affects cells is thus critical to understanding tumorigenesis. Here we show that aneuploidy interferes with the degradation of autophagosomes within lysosomes. Mis-folded proteins that accumulate in aneuploid cells due to aneuploidy-induced proteomic changes overwhelm the lysosome with cargo, leading to the observed lysosomal degradation defects. Importantly, aneuploid cells respond to lysosomal saturation. They activate a lysosomal stress pathway that specifically increases the expression of genes needed for autophagy-mediated protein degradation. Our results reveal lysosomal saturation as a universal feature of the aneuploid state that must be overcome during tumorigenesis. Overall design: RPE-1 cells either untreated or treated with one of Reversine, Bafilomycin A1 or MG132, each condition was done in triplicate. D14-*_Control: untreated control D14-*_Rev: cells treated with 0.5uM Reversine for 24hrs and harvested 48hrs later D14-*_Baf: cells treated with 0.1uM BafA1 for 6hrs D14-*_Mg: cells treated with 1uM MG132 for 24 hrs
Aneuploidy-induced cellular stresses limit autophagic degradation.
No sample metadata fields
View SamplesTranscriptional activation in mammalian embryos occurs in a stepwise manner. In mice, it begins at the late one-cell stage, followed by a minor wave of activation at the early two-cell stage, and then the major genome activation (MGA) at the late two-cell stage. Cellular homeostasis, metabolism, cell cycle, and developmental events are orchestrated before MGA by time-dependent changes in the array of maternal transcripts being translated (i.e., the translatome). Despite the importance of maternal mRNA and its correct recruitment for development, neither the array of recruited mRNA nor the regulatory mechanisms operating have been well cheracterized. We present the first comprehensive analysis of changes in the maternal component of the zygotic translatome during the transition from oocyte to late one-cell stage embryo, revealing global transitions in the functional classes of translated maternal mRNAs, and apparent changes in the underlying cis-regulatory mechanisms.
Analysis of polysomal mRNA populations of mouse oocytes and zygotes: dynamic changes in maternal mRNA utilization and function.
No sample metadata fields
View SamplesThe cholecystokinin B (2) receptor knockout (Cckbr KO) protects against allodynia induced by chronic constriction injury (CCI). The mechanism of this phenomenon is unknown, but must involve persistent changes in pain modulation and/or inflammatory pathways. We performed a gene expression study in two brain areas (midbrain and medulla) after surgical induction of CCI in Cckbr KO and wild-type (wt) control mice. The patterns of gene expression differences suggest that the immune system is activated in higher brain structures following CCI in the wt mice. The strongest differences include genes related to the MAPK pathway activation and cytokine production. In Cckbr KO mice this expressional pattern was absent. In addition, we found significant elevation of the Toll-like receptor 4 (Tlr4) in the supraspinal structures of the mice with deleted Cckbr compared to wt control mice. This up-regulation is most likely induced by the deletion of Cckbr. We suggest that there is a functional deficiency in the Tlr4 pathway which disables the development of neuropathic pain in Cckbr KO mice. Indeed, real time PCR analysis detected a CCI-induced upregulation of Tlr4 and Il1b expression in the lumbar region of wt but not Cckbr KO mice. Gene expression profiling indicates that elements of the immune response are not activated in Cckbr KO mice following CCI. Our findings suggest that there may be a role for CCK in the regulation of innate immunity.
Gene expression profiling reveals upregulation of Tlr4 receptors in Cckb receptor deficient mice.
No sample metadata fields
View SamplesThe aim of this study was to establish an in vitro model to investigate the initial stages of human implantation based on co-culture of a) immortalized cells representing the receptive (Ishikawa) or non-receptive (HEC-1-A) endometrial epithelium with b) spheroids of a trophoblastic cell line (JEG-3) modified to express green fluorescent protein. After co-culturing Ishikawa cells with trophoblast spheroids, 310 and 298 genes increased or decreased their expression compared to non-co-cultured Ishikawa control cells, respectively; only 9 genes (5 increased and 4 decreased) were differentially expressed in HEC-1-A upon co-culture with trophoblast spheroids. Compared to HEC-1-A, the trophoblast challenge to Ishikawa cells differentially regulated the expression of 495 genes. In summary, upon co-culture with the trophoblast spheroids, non-receptive epithelium is characterized by a muted transcriptional response which in turn fails to activate the full transcriptional response that trophoblast spheroids undergo when co-cultured with receptive epithelium. Overall design: GFP expressing JEG-3 spheroids were co-cultured with confluent monolayers of receptive Ishikawa or non-receptive HEC-1-A epithelia. After 48 hours of co-culture, GFP+ (trophoblast JEG-3 spheroid cells) and GFP- cell fractions (receptive Ishikawa or non-receptive HEC-1-A epithelial cells) were isolated by fluorescence-activated flow cytometry (FACS). The specific transcriptional changes of the isolated cell populations were analyzed by RNA-seq profiling. Statistical significance of gene expression differences was set at an absolute log2 fold change (log2FC) =1 and an adjusted p-value <0.05.
Transcriptomic analysis of the interaction of choriocarcinoma spheroids with receptive vs. non-receptive endometrial epithelium cell lines: an in vitro model for human implantation.
Specimen part, Subject
View SamplesAbnormal activities of histone lysine demethylases (KDMs) and lysine deacetylases (HDACs) are associated with aberrant gene expression in breast cancer development. However, the precise molecular mechanisms underlying the crosstalk between KDMs and HDACs in chromatin remodeling and regulation of gene transcription are still elusive. In this study, we showed that treatment of human breast cancer cells with inhibitors targeting the zinc cofactor dependent class I/II HDACs, but not NAD+ dependent class III HDACs, led to significant increase of H3K4me2 which is a specific substrate of histone lysine-specific demethylase 1 (LSD1) and a key chromatin mark promoting transcriptional activation. We also demonstrated that inhibition of LSD1 activity by a pharmacological inhibitor, pargyline, or siRNA resulted in increased acetylation of H3K9 (AcH3K9). However, siRNA knockdown of LSD2, a homolog of LSD1, failed to alter the level of AcH3K9, suggesting that LSD2 activity may not be functionally connected with HDAC activity. Combined treatment with LSD1 and HDAC inhibitors resulted in enhanced levels of H3K4me2 and AcH3K9, and exhibited synergistic growth inhibition of breast cancer cells. Finally, microarray screening identified a unique subset of genes whose expression was significantly changed by combination treatment with inhibitors of LSD1 and HDAC. Our study suggests that LSD1 intimately interacts with histone deacetylases in human breast cancer cells. Inhibition of histone demethylation and deacetylation exhibits cooperation and synergy in regulating gene expression and growth inhibition, and may represent a promising and novel approach for epigenetic therapy of breast cancer.
Inhibitors of histone demethylation and histone deacetylation cooperate in regulating gene expression and inhibiting growth in human breast cancer cells.
Specimen part, Cell line
View Samples