Transcription profiling of mouse pluripotent embryocarcinoma cell line P19 after sodium valproate treatment to investigate its mechanism of teratogenicity
ABSTRACT: In the process of evaluating teratogenic properties of xenobiotica, the consumption of laboratory animals is high and costly which makes the development of alternative methods desirable. The pluripotent embryocarcinoma cell line P19, which closely resembles the early stage of an embryo, may be relevant as an in vitro model of teratogenicity. The antiepileptic drug Valproic acid (VPA) is a potent inducer of neural tube defects (ntd:s) in both human and mouse, but its mechanism of teratogenicity is not know. P19 cells were here treated with sodium valproate in a both time and dose dependent matter to profile the gene expression response with Codelink UniSet Mouse 20K I Bioarrays. This profile may reveal biomarkers of ntd:s as well as give mechanistic input of the teratogenicity of VPA.
Project description:Valproic acid (VPA) is a potent inducer of neural tube defects (ntd:s) in both human and mouse, but its mechanism of teratogenicity is not know. The mouse embryonic stem cell line R1, may be relevant as an in vitro model of teratogenicity and was evaluated with exposures to VPA,and the two VPA anlogs (S)-2-pentyl-4-pentynoic acid, and 2-ethyl-4-methyl-pentanoic acid to profile the gene expression response. Those profiles may reveal biomarkers of teratogenic exposures in an in vitro system as well as give mechanistic input of the teratogenicity of VPA.
Project description:Valproic acid (VPA) is a potent inducer of neural tube defects (NTDs), but its mechanism of teratogenicity is not known. To study the transcriptional response of VPA during the susceptible period, i.e. when VPA is likely to exert most of its teratogenic effect, RNA was extracted from 8.25-dpc embryos (6 h post treatment) from control and VPA-treated dams, and subjected to microarray analysis (four arrays). To be more useful for risk assessment, in vitro models, using cells, may bridge biomarkers discovered by gene expression profiling in an animal in vivo model. Since pluripotent embryocarcinoma (EC) cell lines may be relevant models for early embryonic cells, P19 mouse EC cells were treated with or without 1 mM sodium valproate for 24 h and alos subjected to microarray analysis (four arrays).
Project description:The antiepileptic drug valproic acid (vpa) is known teratogen giving neural tube defects (ntd:s). Administration of vpa to female NMRI on gestation day 8 induces a high incidence of ntd. In this study we investigate the time dependent gene expression changes induced in the embryo 1.5, 3 respectively 6 hr after maternal sodium valproate treatment.
Project description:MicroRNA miRNA expression profiles for human HeLa cells (Cervical cancer), overexpressing p19 H-Ras, were examined to investigate the miRNA regulation by p19 H-Ras. miRNA microarray analysis identified statistical unique profiles, which could discriminate miRNAs regulated by p19 H-Ras and not regulated by the p19 mutant (W164A) H-Ras.
Project description:Neural tube defects (NTDs) are serious birth defects with an estimated worldwide incidence of 1 per 1,000 live births. The multifactorial nature of NTDs in humans has made it difficult to elucidate pathogenesis mechanisms. However, a strong relationship has been established between folate-homocysteine metabolism and NTD risk. Prevention of a substantial proportion of fetal NTDs can be achieved through maternal folic acid (FA) supplementation. However the mechanism by which FA exerts its beneficial effect remains unclear. METHODS: To improve our understanding of the underlying mechanisms of NTD pathogenesis and the ways in which folate exerts its beneficial effect, we analyzed mRNA profiles as well as folate and vitamin B12 levels in five NTD mouse mutants whose response to dietary FA was previously established. RESULTS: Differentially expressed genes representing the effect of each NTD-causing mutation were identified and associated with biologic pathways. Interestingly, the panel of NTD mutants collectively revealed pathways related to two nuclear receptors, retinoid X receptor (RXR) and pregnane X receptor (PXR), suggesting that these pathways may be related to a shared mechanism of NTD development. Moreover, the NTD-causing mutations that were associated with FA responsiveness had expression profiles that were related to folate-homocysteine metabolic pathways. These pathways were not strongly associated with mutants that do not respond to FA supplementation, implying that FA may be beneficial when the NTD mutation affects pathways related to folate-homocysteine metabolism. 5 groups of NTD mutants were studied. From each mutant group Heterozygous (test) and wild-type (control) female pups were used for this study at 6-8 weeks of age. 4 biological replicates were used for each of the test and control groups of each mutant. All mice used for the experiments were fasted 4-5 hours before dissection. A total of 36 samples were analyzed.
Project description:We ortho-topically implanted 16 human colorectal cancer (CRC) cell lines onto the cecal walls of nude mice . To identify the genes possibly involved in EMT of CRC, we analyze the EMT related changes with the orthotopic implantation method in vivo in combination with that of gene expression profiles using a cDNA microarray in vitro. We analyzed 16 human colorectal cancer cell lines. For each cell line, the experiments were carried out twice.
Project description:To reduce cancer mortality, understanding of mechanisms of cancer metastasis is crucial. We have established 6 rat hepatocellular carcinoma (HCC) cell lines, which exhibit differing metastatic potential to the lung after inoculation into the tail veins of nude mice. Micorarray analysis of 4 kinds of HCC cells and rat normal liver tissue was performed to find a potent molecular target for prevention of cancer metastasis. By the microarray analysis, mRNA expression was compared among two low-metastatic rat HCC cell lines (C5F and C6) and two high-metastatic rat HCC cell lines (N1 and L2) as well as non-treated rat liver tissue (as a reference sample).
Project description:The molecular hallmark of the Ewing family of tumors is the presence of balanced chromosomal translocations leading to the formation of chimerical transcription factors (i.e. EWS/FLI1) that play a pivotal role in the pathogenesis of Ewing tumors by deregulating gene expression. We have recently demonstrated that DAX1 (NR0B1), an orphan nuclear receptor which was not previously implicated in cancer, is induced by the EWS/FLI1 oncoprotein and is highly expressed in Ewing tumors, suggesting that DAX1 is a biologically relevant target of EWS/FLI1-mediated oncogenesis. In this work we demonstrate that DAX1 is a direct transcriptional target of the EWS/FLI1 oncoprotein through its binding to a GGA-rich region in the DAX1 promoter and show that DAX1 is a key player of EWS/FLI1-mediated oncogenesis. DAX1 silencing using an inducible model of RNA interference induces growth arrest in the A673 Ewing cell line and severely impairs its capability to grow in semisolid medium and form tumors in immunodeficient mice. Gene expression profile analysis demonstrated that about ten percent of the genes regulated by EWS/FLI1 in Ewing cells are DAX1 targets, confirming the importance of DAX1 in Ewing oncogenesis. These findings indicate that DAX1 is an important player in the pathogenesis of the Ewing family of tumors, identify new functions for DAX1 as a cell cycle progression regulator and open the possibility to new therapeutic approaches based on DAX1 function interference. A673 cells derived from Ewing sarcoma were genetically enginereed to express specific shRNAs against GFP (control), EWS/FLI1 and DAX1 upon doxycycline stimulation. Three independent clones and a polyclonal population from each enginereed cell were analyzed. Cells were stimulated with doxycycline for 72 hours to induce the expression of the corresponding shRNA and whole gene expression profile performed. Gene expression profile in A673 cells in which EWS/FLI1 or DAX1 were silenced were compared to the control cells.
Project description:Mouse macrophages J774A.1 were pre-treated with the anti-inflammatory lipid eicosapenaenoic acid (EPA) or the pro-inflammatory lipid ceramide (Cer) for 3h. Macrophages were then infected with Mycobacterium smegmatis for 1h, and total RNA was collected. In a parallel experiment, infected macrophages were infected for 1h, 4h and 24h. At these time points, macrophages were lysed, bacteria was collected and quantified by the Colony Forming Units (CFU) Assay. This provided the kinetics of the killing of Mycobacteria inside mouse macrophages. CFU experiments revealed that cells pre-treated with EPA showed an increased number of bacteria inside macrophages, in contrast to cells pre-treated with Cer. To dissect the molecular mechanisms involved in the survival and killing of mycobacteria infected macrophages, mediated by lipids, gene expression studies were performed. Cultures of Mycobacterium smegmatis mc2155 harbouring a p19-(long lived) EGFP plasmid were grown to exponential growth phase. Bacteria were pelleted, washed in PBS and resuspended in medium DMEM with a multiplicity of infection (MOI) of 10 (10 bacteria per macrophage). Clumps of bacteria were removed by ultrasonic treatment of bacterial suspensions in an ultrasonic water bath for 15 minutes, followed by a low speed centrifugation for 2 minutes. Mouse macrophages J774A.1 were pre-.treated with the anti-inflammatory lipid eicosapenaenoic acid (EPA) or the pro-inflammatory lipid ceramide (Cer), 3h before infection. Mouse macrophages J774A.1 were infected with Mycobacterium smegmatis mc2155 for 1h, at 37ºC and 5% CO2. After 1h of infection, cells were washed with PBS. After washing, 1 ml Trizol was added per well, to collect total RNA. The experimental condition were: samples 1.1, 1.2, 1.3: Untreated macrophages; samples 2.1, 2.2, 2.3: Mock treated macrophages (ethanol 1ul/ml); samples 3.1, 3.2, 3.3: EPA (15uM) treated macrophages (ethanol 1ul/ml); samples 4.1, 4.2, 4.3: Cer (5ug/ml) treated macrophages (ethanol 1ul/ml); samples 5.1, 5.2, 5.3: Untreated macrophages, infected with Mycobacterium smegmatis mc2155 for 1h; samples 6.1, 6.2, 6.3: Mock treated macrophages (ethanol 1ul/ml) infected with Mycobacterium smegmatis mc2155 for 1h; samples 7.1, 7.2, 7.3: EPA (15uM) treated macrophages (ethanol 1ul/ml) infected with Mycobacterium smegmatis mc2155 for 1h; samples 8.1, 8.2, 8.3: Cer (5ug/ml) treated macrophages (ethanol 1ul/ml) infected with Mycobacterium smegmatis mc2155 for 1h; In a parallel experiment, infected macrophages remained with the bacteria for 1h, 4h and 24h after infection. After these time points, the macrophages were lysed, the bacteria was collected and quantified by the Colony Forming Units (CFU) Assay. This provided the kinetics of the killing of non-pathogenic intracellular bacteria inside mouse macrophages. For the CFU assay, after 1h of infection, cells were washed with PBS and Gentamicin (10ug/ml) in DMEM to kill the extracellular bacteria. At discrete time points, cells were washed with PBS and lysed with sterilized water. Quantitative cultures of bacteria were performed in a 10-fold serial dilutions, inoculated on 7H10 agar plates. 5ul were plated in triplicate and the number of colonies were counted after 48h.