ABSTRACT: In tumor cells, stepwise oncogenic deregulation of signaling cascades induces alterations of cellular morphology and promotes the acquisition of malignant traits. Using a panel of small molecular inhibitors, we established associated gene expression signatures of key signaling hubs. SW480 cells were grown in DMEM, 10% FCS, and treated for 24h with the following inhibitors or with solvent (DMSO): SU5402 (42uM); U0126 (10uM), SP600125 (20uM), LY294002 (20uM)
Project description:Genomic expression profiles of blood and placenta reveal significant immune-related pathways and categories in Chinese women with Gestational Diabetes Gestational diabetes mellitus (GDM) is a complex metabolic disease which occurs in pregnancy with high prevalence, and its pathogenesis remains elusive. Thus far, there has been no comprehensive gene expression profiling in Chinese women with GDM. In this study, we attempt to define the genes and/or pathways that are involved in GDM with Chinese ethnicity, by the Illumina microarray technique. We found 5,197 and 243 genes with significantly altered expression due to GDM in blood and placenta tissues, respectively. Previously known genes (such as TNF, IL1B, LEP, IFNG, and HLA-G) with altered gene expression in GDM were also validated here. In addition, we identified undescribed genes VAV3, PTPN6, CD48 and IL15, in which expression was related to GDM by microarray and Q-RT-PCR assays. To identify GDM-associated pathways, we used analyses with integrated functional annotation (i.e. KEGG) and extracted two significant pathways, which were Natural killer cell mediated cytotoxicity (hsa04650; FDR = 7.10E-09) in blood and Cytokine-cytokine receptor interaction (hsa04060; FDR = 1.07E-03) in placenta tissues. Immune system process (GO: 0002376) was identified by GO analysis with FDR P-value = 7.01E-60 in blood and FDR P-value = 3.57E-08 in placenta tissues, indicating the importance of immunological and inflammatory categories in GDM. Furthermore, despite differences in the quantity of gene expression, we observed a similar functional distribution between expression of blood and placenta tissues in GDM under the categories of immunity. These newly identified key genes and pathways may provide valuable information for the pathogenesis of GDM and advance disease diagnosis, prevention, medication design, and clinical treatment of the disease. One individual GDM blood tissue sample and one pooled GDM blood tissue sample were compared to one pooled healthy blood tissue sample. One pooled GDM placenta tissue sample was compared to one pooled healthy placenta tissue sample.
Project description:We aimed to expand the knowledge of Fgf and Wnt signaling in the zebrafish tailbud. Both pathways are required for proper axis elongation and segmentation and we wished to explore the genes under the control of each pathway during this process. In addition, we saught to identify crosstalk between the two pathways by determining whether pathway effector expression was being changed after time-resolved modification of each pathway using pharmacological modifiers. Embryos were treated with either 0.3M LiCl, 50uM SU5402, or E2 for 3hours or 7 hours (E2 and SU5402), followed by tailbud dissection and RNA extraction. Conditions were replicated in triplicate.
Project description:TGF-beta plays multiple functions in a board range of cellular responses such as proliferation, differentiation, motility and survival by activating several cellular signaling pathways, including Smads and MAP kinases (Erk, JNK and p38). In particular, TGF-beta can activate pro- or anti-apoptotic signals depending on the target cells. We found that blockage of JNK activation sensitized mouse B lymphoma derived A20 cells to TGF-beta-induced apoptosis. These results suggest that TGF-beta activate JNK to inhibit the activation of death signal that is simultaneously activated by TGF-beta. We used microarrays to gain insight into the effects of JNK inhibition on gene expression in TGF-b-stimulated A20 cells and identified JNK-dependent TGF-beta inducible genes. Experiment Overall Design: The following six samples were prepared: untreated A20 cells (non-stimulated, DMSO): A20 cells cultured with SP600125 for 24 h (non-stimulated, SP600125): A20 cells stimulated with TGF-beta for 12 h (TGF-beta 12 h, DMSO) and 24 h (TGF-beta 24 h, DMSO): and A20 cells stimulated with TGF-beta in the presence of SP600125 for 12 h (TGF-beta 12 h, SP600125) and 24 h (TGF-beta 24 h, SP600125), respectively. Total RNA was prepared and hybridized to the Affymetrix Mouse Genome 430 2.0 array. Genes whose expression was increased by more than 2-fold at either 12 or 24 h after TGF-beta stimulation were identified as TGF-beta inducible genes. Amongst them, we identified genes whose induction levels were reduced by more than 75% by co-treatment with the JNK inhibitor SP600125.
Project description:Transcriptional profiling of mouse spermatogonial stem cells (SSCs) comparing control untreated SSCs with SSCs with exogenous FGF2 withdrawn and FGFR inhibitor SU5402 supplemented (-F+S). Results provide insight into the mechanisms of FGF2-supported in vitro self-renewal of SSCs. Two-condition experiment, SSCs-F+S vs. SSCs. Biological replicates: 4 control replicates, 4 -F+S replicates.
Project description:Inhibitors of the MAPKs, BRAF and MEK, induce tumor regression in the majority of patients with BRAF-mutant metastatic melanoma. The clinical benefit of MAPK inhibitors is restricted by the development of acquired resistance with half of those who benefit having progressed by 6-7 months and long-term responders uncommon. There remains no agreed treatment strategy on disease progression in these patients. Without published evidence, fears of accelerated disease progression on inhibitor withdrawal have led to the continuation of drugs beyond formal disease progression. We now demonstrate that treatment with MAPK inhibitors beyond disease progression can provide significant clinical benefit, and the withdrawal of these inhibitors led to a marked increase in the rate of disease progression in two patients. We also show that MAPK inhibitors retain partial activity in acquired resistant melanoma by examining drug-resistant clones generated to dabrafenib, trametinib or the combination of these drugs. All resistant sublines displayed a markedly slower rate of proliferation when exposed to MAPK inhibitors, and this coincided with a reduction in MAPK signalling, decrease in BrdU incorporation and S-phase inhibition. This cytostatic effect was also associated diminished levels of cyclin D1 and p-pRb.. Two short-term melanoma cultures generated from resistant tumour biopsies also responded to MAPK inhibition with comparable inhibitory changes in proliferation and MAPK signalling. These data provide a rationale for the continuation of BRAF and MEK inhibitors after disease progression and support the development of clinical trials to examine this strategy. Total RNA obtained from melanooma cell lines treated for 24h with dabrafenib, trametinib or combination of dabrafenib and trametinib
Project description:St. 14 embryos were incubated in 100mM of a Jnk inhibitor (SP600125)-0,1x MBS until stage 24. Embryonic epidermis was isolated and stored immediately in chilled (4°C) Trizol. We sought to uncover all the putative targets of Jnk expresssed in the embryonic epidermis whole embryonic skin was isolated and immediately stored in chilled trizol Xenopus embryos skins were isolated at stage 24 of early development for Trizol RNA extraction and hybridization on Affymetrix microarrays. Each sample contains 20 whole embryonic skins
Project description:In inflamed tissue, normal signal transduction pathways are altered by extracellular signals. For example, the JNK pathway is activated in psoriatic skin, which makes it an attractive target for treatment. To define comprehensively the JNK-regulated genes in human epidermal keratinocytes, we compared the transcriptional profiles of control and JNK inhibitor-treated keratinocytes, using DNA microarrays. We identified the differentially expressed genes 1, 4, 24, and 48 h after the treatment with SP600125. Surprisingly, the inhibition of JNK in keratinocyte cultures in vitro induces virtually all aspects of epidermal differentiation in vivo: transcription of cornification markers, inhibition of motility, withdrawal from the cell cycle, stratification, and even production of cornified envelopes. The inhibition of JNK also induces the production of enzymes of lipid and steroid metabolism, proteins of the diacylglycerol and inositol phosphate pathways, mitochondrial proteins, histones, and DNA repair enzymes, which have not been associated with differentiation previously. Simultaneously, basal cell markers, including integrins, hemidesmosome and extracellular matrix components, are suppressed. Promoter analysis of regulated genes finds that the binding sites for the forkhead family of transcription factors are over-represented in the SP600125-induced genes and c-Fos sites in the suppressed genes. The JNK-induced proliferation appears to be secondary to inhibition of differentiation. The results indicate that the inhibition of JNK in epidermal keratinocytes is sufficient to initiate their differentiation program and suggest that augmenting JNK activity could be used to delay cornification and enhance wound healing, whereas attenuating it could be a differentiation therapy-based approach for treating psoriasis.
Project description:Heart formation requires input from two populations of progenitor cells - the first and second heart fields - that differentiate at distinct times and create different cardiac components. The cardiac outflow tract (OFT) is built through recruitment of late-differentiating, second heart field (SHF) -derived cardiomyocytes to the arterial pole of the heart. Mechanisms responsible for selection of an appropriate number of OFT cells from the SHF remain unclear, although several lines of evidence emphasize the importance of FGF signaling in promoting this process. Here, we examine the impact of inhibition of FGF signaling on cardiac transcription profiles in an effort to identify genes operating downstream of FGF during OFT development. We compared hearts from embryos treated with the FGFR inhibitor SU5402 to the hearts from sibling embryos treated with DMSO. Two replicates were performed.
Project description:Epidermal keratinocytes respond to extracellular influences by activating cytoplasmic signal transduction pathways that change the transcriptional profiles of affected cells. To define responses to two such pathways, p38 and ERK, we used SB203580 and PD98059 as specific inhibitors, and identified the regulated genes after 1, 4, 24 and 48 hrs, using Affymetrix’ Hu133Av2 microarrays. Additionally, we compared genes specifically regulated by p38 and ERKs with those regulated by JNK and by all three pathways simultaneously. We find that the p38 pathway induces the expression of extracellular matrix and proliferation-associated genes, while suppressing microtubule-associated genes; the ERK pathway induces the expression of nuclear envelope and mRNA splicing proteins, while suppressing steroid synthesis and mitochondrial energy production enzymes. Both pathways promote epidermal differentiation and induce feedback inactivation of MAPK signaling. c-FOS, SRY and N-Myc appear to be the principal targets of the p38 pathway, Elk-1 SAP1 and HLH2 of ERK, while FREAC-4, ARNT and USF are common to both. The results for the first time comprehensively define the genes regulated by the p38 and ERK pathways in epidermal keratinocytes and suggest a list of targets potentially useful in therapeutic interventions. Human epidermal keratinocytes are grown in Keratinocyte Serum-Free Medium (Gibco) supplemented with 0.05 mg/ml bovine pituitary extract, 2.5 ng/ml epidermal growth factor, 0.09 mM CalCl2 and 1% penicillin/streptomycin (KGM). They are switched to Keratinocyte Serum Free-Media (Gibco) supplemented only with 1% penicillin/streptomycin (KBM) 24 h prior to commencing experiments. A set is left as controls, others treated with 5 uM JNK inhibitor SP600125, 15 uM p38 inhibitor SB203580, or 50 um ERK inhibitor PD98059. Timecourse of treated and parellel control samples over a 48 hr period was performed.
Project description:The transcriptional profile of Escherichia coli O157 treated with small molecule inhibitors of type III secretion was determined. Four variations of the small molecule inhibitor were assessed for global changes in transcription by treating cells with 20uM of inhibitor or an equivalent volume of DMSO (inhibitor solvent). Keywords: treatment, dose, Cy3, Cy5, 2-colour For each inhibitor, biological tripicates of treated (20uM inhibitor in DMSO) and untreated (DMSO only) cultures were grown in 25ml of MEM-HEPES supplemented with 0.1% Glucose and 250nM Fe(NO3)2. RNA was extracted from 15ml of culture at OD 0.7 and labeled with Cy5 (treated) and Cy3 (untreated) (excepting ME0055 that was performed as a dye swap). Labeled untreated RNA was pooled prior to hybridisation. Treated RNA (biological replicates) and pooled untreated RNA was hybridised to microarray slides. Slides were scanned using an Axon 4100A scanner and data processed using Genespring GX.