This SuperSeries is composed of the SubSeries listed below.
Combined Gene Expression and RNAi Screening to Identify Alkylation Damage Survival Pathways from Fly to Human.
Specimen part, Treatment
View SamplesDespite the high toxicity, alkylating agents are still at the forefront of several clinical protocols used to treat cancers. In this study, we investigated the mechanisms underlying alkylation damage responses, aiming to identify novel strategies to augment alkylating therapy efficacy. In this pursuit, we compared gene expression profiles of evolutionary distant cell types (D. melanogaster Kc167 cells, mouse embryonic fibroblasts and human cancer cells) in response to the alkylating agent methyl-methanesulfonate (MMS). We found that many responses to alkylation damage are conserved across species independent on their tumor/normal phenotypes. Key amongst these observations was the protective role of NRF2-induced GSH production primarily regulating GSH pools essential for MMS detoxification but also controlling activation of unfolded protein response (UPR) needed for mounting survival responses across species. An interesting finding emerged from a non-conserved mammalian-specific induction of mitogen activated protein kinase (MAPK)-dependent inflammatory responses following alkylation, which was not directly related to cell survival but stimulated the production of a pro-inflammatory, invasive and angiogenic secretome in cancer cells. Appropriate blocking of this inflammatory component blocked the invasive phenotype and angiogenesis in vitro and facilitated a controlled tumor killing by alkylation in vivo through inhibition of alkylation-induced angiogenic response, and induction of tumor healing.
Combined Gene Expression and RNAi Screening to Identify Alkylation Damage Survival Pathways from Fly to Human.
Specimen part, Treatment
View SamplesMost of the transcriptional changes induced by PFOS in the fetal mouse liver and lung were related to activation of PPARalpha. When compared to the transcript profiles induced by PFOA (Pubmed ID 17681415), few remarkable differences were found other than up-regulation of Cyp3a genes. Because PFOS and PFOA have been shown to differ in their mode of action in the murine neonate, these data suggest that changes related to PFOS-induced neonatal toxicity may not be evident in the fetal transcriptome at term.
Gene expression profiling in the liver and lung of perfluorooctane sulfonate-exposed mouse fetuses: comparison to changes induced by exposure to perfluorooctanoic acid.
No sample metadata fields
View SamplesPerfluorooctane sulfonate (PFOS) is a perfluoroalkyl acid (PFAA) and a persistent environmental contaminant found in the tissues of humans and wildlife. Although blood levels of PFOS have begun to decline, health concerns remain because of the long half-life of PFOS in humans. Like other PFAAs, such as perfluorooctanoic acid (PFOA), PFOS is an activator of peroxisome proliferator-activated receptor-alpha (PPAR) and exhibits hepatocarcinogenic potential in rodents. PFOS is also a developmental toxicant in rodents where, unlike PFOA, its mode of action is independent of PPAR. Wild-type (WT) and PPAR-null (Null) mice were dosed with 0, 3, or 10 mg/kg/day PFOS for 7 days. Animals were euthanized, livers weighed, and liver samples collected for histology and preparation of total RNA. Gene profiling was conducted using Affymetrix 430_2 microarrays. In WT mice, PFOS induced changes that were characteristic of PPAR transactivation including regulation of genes associated with lipid metabolism, peroxisome biogenesis, proteasome activation, and inflammation. PPAR-independent changes were indicated in both WT and Null mice by altered expression of genes related to lipid metabolism, inflammation, and xenobiotic metabolism. Such results are similar to prior studies done with PFOA and are consistent with modest activation of the constitutive androstane receptor (CAR) and possibly PPAR and/or PPAR/. Unique treatment-related effects were also found in Null mice including altered expression of genes associated with ribosome biogenesis, oxidative phosphorylation and cholesterol biosynthesis. Of interest was up-regulation of Cyp7a1, a gene which is under the control of various transcription regulators. Hence, in addition to its ability to modestly activate PPAR, PFOS induces a variety of off-target effects as well.
Gene Expression Profiling in Wild-Type and PPARα-Null Mice Exposed to Perfluorooctane Sulfonate Reveals PPARα-Independent Effects.
Sex, Specimen part, Treatment
View SamplesThese data are from the brains (amygdala and hippocampus) of mice originally derived from a cross between C57BL/6J and DBA/2J inbred strains. We used short-term selection to produce outbred mouse lines with differences in contextual fear conditioning, which is a measure of fear learning. We selected for a total of 4 generations. Fear learning differed in the selected lines and this difference was stronger with each successive generation of selection. These mice also showed differences for measures of anxiety-like behavior, but were not different for tests of non-fear motivated learning, suggesting that selection altered alleles that are specifically involved in emotional behaviors. We identified several QTLs for the selection response. We used Affymetrix microarrays to identify differentially expressed genes in the amygdala and hippocampus of mice from the final generation of selection. Amygdala and hippocampus samples were rapidly dissected out of experimentally nave mice f rom each selected line. Three samples were pooled and hybridized to each array. Experimentally nave mice were used because the behavior of the mice can be reliably anticipated due to their lineage. Thus, these gene expression differences are not due to the response to human handling, foot shock or fear-inducing conditioned stimuli. We have a second similar study that focuses on a different selected population that was based on C57BL/6J and A/J mice (see GES4034).
Selection for contextual fear conditioning affects anxiety-like behaviors and gene expression.
No sample metadata fields
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