Mice deficient in the glucocorticoid-regenerating enzyme 11-HSD1 resist age-related spatial memory impairment. To investigate the mechanisms/pathways involved, we used microarrays to identify differentially expressed hippocampal genes that associate with cognitive ageing and 11-HSD1. Aged wild-type mice were separated into memory-impaired and unimpaired relative to young controls according to their performance in the Y-maze. All individual aged 11-HSD1-deficient mice showed intact spatial memory. The majority of differentially expressed hippocampal genes were increased with ageing (e.g. immune/inflammatory response genes) with no genotype differences. However, the neuronal-specific transcription factor, Npas4 and immediate early gene, Arc were reduced (relative to young) in the hippocampus of memory-impaired but not unimpaired aged wild-type or aged 11-HSD1-deficient mice. Quantitative RT-PCR and in situ hybridization confirmed reduced Npas4 and Arc mRNA expression in memory-impaired aged wild-type mice. These findings suggest that 11-HSD1 may contribute to the decline in Npas4 and Arc mRNA levels associated with memory impairment during ageing, and that decreased activity of synaptic plasticity pathways involving Npas4 and Arc may, in part, underlie the memory deficits seen in cognitively-impaired aged wild-type mice.
Decreased Npas4 and Arc mRNA Levels in the Hippocampus of Aged Memory-Impaired Wild-Type But Not Memory Preserved 11β-HSD1 Deficient Mice.
Age
View SamplesPurpose: The phosphoinositide 3-kinase (PI3K) pathway is fundamental for cell proliferation and survival and is frequently altered and activated in neoplasia, including carcinomas of the lung. In this study we investigated the potential of targeting the catalytic class IA PI3K isoforms in small cell lung cancer (SCLC), which is the most aggressive of all lung cancer types. Experimental Design: The expression of PI3K isoforms in patient specimens was analyzed. The effects on SCLC cell survival and downstream signaling were determined following PI3K isoform inhibition by selective inhibitors or down-regulation by small interfering RNA. Results: Over-expression of the PI3K isoforms p110 and p110 was shown by immunohistochemistry in primary SCLC tissue samples. Targeting the PI3K p110 with RNA interference (RNAi) or selective pharmacological inhibitors resulted in strongly affected cell proliferation of SCLC cells in vitro and in vivo, while targeting p110 was less effective. Inhibition of p110 also resulted in increased apoptosis and autophagy, which was accompanied by decreased phosphorylation of Akt and components of the mammalian target of rapamycin (mTOR) pathway, such as the ribosomal S6 protein, and the eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1). A DNA microarray analysis revealed that p110 inhibition profoundly affected the balance of pro- and anti-apoptotic Bcl-2 family proteins. Finally, p110 inhibition led to impaired SCLC tumor formation and vascularization in vivo. Conclusion: Together our data demonstrate the key involvement of the PI3K isoform p110 in multiple tumor-promoting processes in SCLC.
Targeting the phosphoinositide 3-kinase p110-α isoform impairs cell proliferation, survival, and tumor growth in small cell lung cancer.
Cell line, Treatment
View SamplesComparing the transcriptome of wildtype and kdm5 mutant flies in normal conditions revealed a total of 4787 genes that were significantly downregulated and thus require KDM5 for their activation, and 3269 upregulated genes that are normally repressed by KDM5 (p<0.05, FDR <0.05). Because kdm5 mutants are sensitive to the oxidizer paraquat, we also carried out RNA-seq from wildtype and kdm5 mutant adults in oxidative stress conditions. Paraquat treatment of wildtype flies lead to the upregulation of 2481, and downregulation of 3103 genes Overall design: adult mRNA profiles of 1-3-days old wild type (WT) and kdm5 mutant under normal condition and oxitative stress were generated by deep sequencing, using Illumina HisSeq 2000.
The Histone Demethylase KDM5 Activates Gene Expression by Recognizing Chromatin Context through Its PHD Reader Motif.
Sex, Specimen part, Subject
View SamplesEmbolism and the refilling of xylem vessels are intrinsic to the ability of plants to handle the transport of water under tension. While the formation of an embolized vessel is an abiotic process, refilling against the pressure gradient requires biological activity to provide both the energy and the water needed to restore xylem transport capacity.
Transcriptome response to embolism formation in stems of Populus trichocarpa provides insight into signaling and the biology of refilling.
Specimen part, Treatment
View SamplesAryl hydrocarbon receptor (AHR) activation by tryptophan (Trp) catabolites enhances tumor malignancy and suppresses anti-tumor immunity. Hitherto, indoleamine-2,3-dioxygenase 1 (IDO1) or tryptophan- 2, 3-dioxygenase (TDO2) are recognized as the main Trp-catabolizing enzymes (TCEs) responsible for the generation of AHR agonists. Here, the ability of the aromatic L-amino acid oxidase, interleukin 4 induced 1 (IL4I1), to activate the AHR was investigated using IL4I1 knockout CAS-1 glioblastoma cells.
IL4I1 Is a Metabolic Immune Checkpoint that Activates the AHR and Promotes Tumor Progression.
Cell line
View SamplesAnalysis of the effect of IL4I1 on gene expression of CD8 T-cells in CLL
IL4I1 Is a Metabolic Immune Checkpoint that Activates the AHR and Promotes Tumor Progression.
Sex
View SamplesIndole-3-pyruvate (I3P), an endogenous metabolite derived from tryptophan by gut microbiota and IL4I1 enzyme in humans can potentially activate the transcriptional activity of the Aryl Hydrocarbon receptor. Here we test this by stimulating AHR proficient U-87MG cells with I3P alone or in combination with the AHR antagonist SR1.
IL4I1 Is a Metabolic Immune Checkpoint that Activates the AHR and Promotes Tumor Progression.
Cell line
View SamplesThe present study was designed to identify Mkl1 target genes whose expression requires either the B1 site of Mkl1 and serum response factor (SRF), respectively, or the SAP domain of Mkl1. For this purpose, we obtained the transcriptomes of four stable 4T1 cell lines that either overexpress full length Mkl1-RFP (4T1-FL), Mkl1-RFP with a mutated SRF-interaction site (4T1-mutB1), Mkl1-RFP with a deletion of the SAP domain (4T1-SAP) or an empty vector encoding RFP alone (4T1 control).
Mechanism of irradiation-induced mammary cancer metastasis: A role for SAP-dependent Mkl1 signaling.
Specimen part, Cell line
View SamplesEwing Sarcoma is the second most common solid pediatric malignant neoplasm of the bone and soft tissue. Driven by EWS/Ets, or rarely variant, oncogenic fusions, Ewing Sarcoma is a biologically and clinically aggressive disease with a high propensity for metastasis. Our laboratory has previously identified the Jumonji-domain H3K9 me 1/2 histone demethylase KDM3A as a novel oncogene downstream of EWS/Fli1, the most common oncofusion in Ewing Sarcoma. Herein, we uncover a role for KDM3A in the promotion of Ewing Sarcoma metastasis.
The histone demethylase KDM3A, and its downstream target MCAM, promote Ewing Sarcoma cell migration and metastasis.
Cell line
View SamplesThe present study was designed to identify genes induced by irradiation in the 4T1 breast cancer model mimicking aggressive local relapse after radiotherapy. For this purpose, we obtained the transcriptomes of 4T1 tumors grown in either preirradiated (IRR+4T1) or non-irradiated (4T1) mammary tissue.
Mechanism of irradiation-induced mammary cancer metastasis: A role for SAP-dependent Mkl1 signaling.
Specimen part
View Samples