The effects of naltrexone on gene expression in HCT116 colorectal cancer cell line
Ontology highlight
ABSTRACT: A number of reports have identified a putative anticancer role for naltrexone when used at doses lower than those conventionally administered. In particular, it has been shown that these low doses of naltrexone are able to suppress tumour growth. A definitive mechanism of action has yet to be established, but what is known is that the effect can be via modifications to the host immune system rendering it more anticancer in nature, or through direct antagonism of tumour growth. Our current paper uses gene expression as a way of unraveling this.The human colorectal cancer cell line HCT116 was cultured in medium alone, or with naltrexone at two different doses for 4 hours. Cells were either harvested after this time or transferred into fresh medium for a further 24 hours before being harvested. RNA was isolated from these cells by Trizol. Total RNA was labelled and hybridised to Illumina Human HT-12v4 arrays.
Project description:Synthetic amorphous silica (SAS) is a nanomaterial used in a wide variety of applications, including the use as a food additive. Two types of SAS are commonly employed as a powder additive, precipitated silica and fumed silica. Numerous studies have investigated the effects of synthetic amorphous silica on mammalian cells. However, most of them have used an exposure scheme based on a single dose of SAS. In this study, we have used instead a repeated 10-days exposure scheme, closer to the occupational exposure encountered in daily life. As a biological model we have used the murine macrophage cell line J774A.1, as macrophages are very important innate immune cells in the response to particulate materials. In order to get a better appraisal of the macrophage responses to this repeated exposure to SAS, we have used proteomics as a wide-scale approach. Furthermore, some of the biological pathways detected as modulated by the exposure to SAS by the proteomic experiments have been validated through targeted experiments. Overall, proteomics showed that precipitated SAS induced a more important macrophage response than fumed SAS at equal dose. Nevertheless, validation experiments showed that most of the responses detected by proteomics are indeed adaptive, as the cellular homeostasis appeared to be maintained at the end of the exposure. For example, the intracellular glutathione levels or the mitochondrial transmembrane potential at the end of the 10 days exposure were similar for SAS-exposed cells and for unexposed cells. Nevertheless, important functions of macrophages such as phagocytosis, TNF and interleukin-6 secretion were up-modulated after exposure, as was the expression of important membrane proteins such as the scavenger receptor or the MAC-1 receptor. These results suggest that repeated exposure to low doses of SAS slightly modulates the immune functions of macrophages, which may alter the homeostasis of the immune system.
Project description:This SuperSeries is composed of the following subset Series:; GSE14383: Effects of chronic exposure of human bronchial epithelial cells to low doses of cigarette smoke condensate; GSE14385: Response of bronchial epithelial cells to low doses of cigarette smoke condensate and subsequent demethylation agent Experiment Overall Design: Refer to individual Series
Project description:We report the genome-wide profiling of FXR binding by ChIP-seq from GW4064 or DMSO treated primary human hepatocytes. We reported altered RNA expression profiles in primary human hepatocypes upon GW4064 treatment compared to DMSO control by RNA-seq. We also reported the altered RNA expression profiles in livers from WT C57BL/6J mice upon GW4064 treatment compared to vehicle control. Primary human hepatocytes were treated with 5uM GW4064 or DMSO control, 1 hour later, cells were fixed and collected for chromatin isolation. 24 hours post treatment, cells were isolated for RNA isolation. This submission represents HTS component of study.
Project description:FLAG-SAMP3ylated proteins were immunoprecipitated from Haloferax volcanii using anti-FLAG affinity agarose and separated using SDS-PAGE. The Coomassie-stained IP-bands represented FLAG-SAMP3ylated proteins harvested from the wild type and also from the ubaA mutant as negative control. The Coomassie-lanes from the IP samples were cut into 10 fractions and in-gel tryptic digested and the tryptic peptides measured using Orbitrap Velos LC-MS/MS.
Project description:Berberine, an isoquinoline alkaloid isolated from many medicinal herbs such as Coptis chinensis, has a wide range of pharmacological effects. Here, we used gene expression microarray to analyze gene expression profiles of HepG2 human hepatoma cell line after berberine chloride treatment or 0.08% DMSO as control. Comparing gene expression profiles of 40 M-BM-5M-BM--M berberine-treated HepG2 human hepatoma cell line to those of control cells sampled after 4 hours treatment. A 50 mM stock solution of Berberine chloride was prepared in DMSO. Cells were treated with 40 M-BM-5M-BM--M berberine chloride or 0.08% DMSO as control.
Project description:Knowing the exact positions of nucleosomes not only advances our understanding of their role in gene regulation, but also the mechanisms that underlie between-species variation in chromatin structure. We have generated a chemical map of nucleosomes in vivo in Schizosaccharomyces pombe at base pair resolution. This new map reveals that S.pombe genome shares a similar periodic linker length distribution with Saccharomyces cerevisiae, but with major distinctions in nucleosomal/linker DNA sequence features. In S.pombe, A/T rich sequences are enriched in the nucleosome core region, particularly +/-20 bp of dyad, while they are disfavored in S.cerevisiae nucleosomes. The poly (dA-dT) tracts only slightly affect the nucleosome occupancy in S.pombe; and they possess preferential rotational positions within the nucleosome core with significant enrichment in the 10-30 bp region from the dyad for longer tracts. S.pombe does not have well-defined nucleosome free region immediately upstream of most transcription start sites (TSS), instead the -1 nucleosome is positioned with regular distance to the +1 nucleosome, and its occupancy is negatively correlated with gene expression. The nucleosomes around TSS show more pronounced bidirectional phasing when the intergenic distance is relatively short, and the downstream nucleosome positioning is strongly correlated with DNA sequence features. We discovered that heterochromatin regions tend to have sparse nucleosome positioning, mixed with both well-positioned and fuzzy nucleosomes. The S.pombe map suggests that some of nucleosome positioning codes, formerly thought to be intrinsic, may largely depend on species-specific extrinsic factors including linker histone, chromatin remodelers and other DNA-binding proteins. 2 samples were analyzed with high throughput paired-end parallel sequencing. Both samples were created using the same chemical mapping protocol
Project description:Toxicoepigenetics is an emerging field that studies the toxicological impact of compounds on protein expression through heritable, non-genetic mechanisms, such as histone post-translational modifications (hPTMs). Due to substantial progress in the large-scale study of hPTMs, integration into the field of toxicology is a promising addition that offers the opportunity to gain novel insights into toxicological phenomena. Moreover, there is a growing demand for high-throughput human-based in vitro assays for toxicity testing and especially for developmental toxicity. Consequently, we developed a mass spectrometry based proof-of-concept to develop an assay to screen the histone code and hence detecting multiple hPTMs changes simultaneously in human embryonic stem cells. To prove the applicability and performance, we first validated the untargeted workflow with valproic acid (VPA), a histone deacetylase inhibitor. These results demonstrate that our workflow is capable of mapping the hPTM-dynamics, with a general increase in acetylations as an internal control. To illustrate the scalability, the workflow was applied on a proof-of-concept dose-response library of a total of ten compounds with either i) a known effect on the hPTMs (BIX-01294, 3-Deazaneplanocin A, Trichostatin A, and VPA), ii) a presumed developmental toxicity, including compounds of abuse (Caffeine, Ethanol, Nicotine, Methotrexate, and All-trans retinoic acid), or iii) no proven embryotoxicity (Penicillin G). In conclusion, we show that toxicoepigenetic screening on histones is feasible and yields very rich data that holds great potential, not only for applications in the pharmaceutical industry, but also for environmental toxicity and food safety.
Project description:BEAS-2B cells have been treated with low doses (20 ug/ml) of CSC for 4 months. As negative control BEAS-2B cells were treated with DMSO (the CSC solvent). Non-treated cells were cultivated in parallel. Experiment Overall Design: After each month total RNA was extracted from three replicates of CSC, DMSO and non-treated BEAS-2B cells and hybridized to Affymetrix GeneChips.
Project description:ecent development of mass spectrometer cleavable protein cross-linkers and algorithms for their spectral identification now permits large-scale cross-linking mass spectrometry (XL-MS). Here, we optimized the use of cleavable disuccinimidyl sulfoxide (DSSO) cross-linker for labeling native protein complexes in live human cells. We applied a generalized linear mixture model to calibrate cross-link peptide-spectra matching (CSM) scores to control the sensitivity and specificity of large-scale XL-MS. Using specific CSM score thresholds to control the false discovery rate, we found that higher-energy collisional dissociation (HCD) and electron transfer dissociation (ETD) can both be effective for large-scale XL-MS protein interaction mapping. We found that the density and coverage of protein-protein interaction maps can be significantly improved through the use of multiple proteases. In addition, the use of sample-specific search databases can be used to improve the specificity of cross-linked peptide spectral matching. Application of this approach to human chromatin labeled in live cells recapitulated known and revealed new protein interactions of nucleosomes and other chromatin-associated complexes in situ. This optimized approach for mapping native protein interactions should be useful for a wide range of biological problems.
Project description:The transcriptomics changes induced in the human liver cell line HepG2 by low and high doses of acetaminophen and solvent controls after treatment for 4 time points (12h, 24h, 48h and 72h) The study investigated differential gene expression in HepG2 cell line mRNA following 12 to 72 hours of exposure to low and high doses of acetaminophen and solvent controls. Three biological replicates per compound/solvent.