Hypoxia promotes an aggressive tumor phenotype with increased genomic instability, partially due to downregulation of DNA repair pathways. However, in addition to DNA repair, genome stability is also controlled by cell cycle checkpoints. An important issue is therefore whether hypoxia also can alter the DNA damage cell cycle checkpoints. Here, we show that hypoxia (24h 0.2% O2) alters the expression of several G2 checkpoint regulators, as examined by microarray gene expression analysis and immunoblotting of U2OS cells. While some of the changes reflected hypoxia-induced inhibition of cell cycle progression, flow cytometric bar-coding analysis of individual cells showed that the levels of several G2 checkpoint regulators were reduced in G2 phase cells after hypoxic exposure, in particular cyclin B1. These effects were accompanied by decreased Cyclin dependent kinase (CDK) activity in G2 phase cells after hypoxia. Furthermore, cells pre-exposed to hypoxia showed a longer G2 checkpoint arrest upon treatment with ionizing radiation. Similar results were found following other hypoxic conditions (~0.03 % O2 20h and 0.2% O2 72h). These results demonstrate that the DNA damage G2 checkpoint can be altered as a consequence of hypoxia, and we propose that such alterations may influence the genome stability of hypoxic tumors.
Hypoxia-induced alterations of G2 checkpoint regulators.
Specimen part, Cell line
View SamplesWe explored the prognostic impact of the dynamic contrast enhanced MR imaging (DCE-MRI) parameter ABrix in cervical cancer combined with global gene expression data to reveal the underlying molecular phenotype of the parameter and construct a gene signature that reflected ABrix. Based on 78 cervical cancer patients subjected to curative chemoradiotherapy, we identified a prognostic ABrix parameter by pharmacokinetic analysis of DCE-MR images based on the Brix model, where tumors with low ABrix appeared to be most aggressive. Gene set enrichment analysis of 46 tumors with pairwise DCE-MRI and gene expression data showed a significant correlation between ABrix and the hypoxia gene sets, whereas gene sets related to proliferation, radioresistance, and wound healing were not significant. Hypoxia gene sets specific for cervical cancer created in cell culture experiments, including targets of the hypoxia inducible factor (HIF1) and the unfolded protein response (UPR), were the most significant. In the remaining 32 tumors, low ABrix was associated with upregulation of HIF1 protein expression, as assessed by immunohistochemistry, consistent with increased hypoxia. Based on the hypoxia gene sets, a signature of 31 genes that were upregulated in tumors with low ABrix was constructed. This DCE-MRI hypoxia gene signature showed prognostic impact in an independent validation cohort of 109 patients.
Hypoxia-induced gene expression in chemoradioresistant cervical cancer revealed by dynamic contrast-enhanced MRI.
Specimen part, Cell line, Treatment
View SamplesType I interferons were discovered as the primary antiviral cytokines and are now known to serve critical functions in host defense against bacterial pathogens. Accordingly, established mediators of interferon antiviral activity may mediate previously unrecognized antibacterial functions. RNase-L is the terminal component of an RNA decay pathway that is an important mediator of interferon-induced antiviral activity. Here we identify a novel role for RNase-L in the host antibacterial response. RNase-L-/- mice exhibited a dramatic increase in mortality following
An essential role for the antiviral endoribonuclease, RNase-L, in antibacterial immunity.
No sample metadata fields
View SamplesHepatocellular carcinoma (HCC) is a highly prevalent and deadly disease world-wide. The survival of HCC patients is usually very poor due to the lack of efficient anti-cancer drugs
Synthesis and bio-molecular study of (+)-N-Acetyl-α-amino acid dehydroabietylamine derivative for the selective therapy of hepatocellular carcinoma.
Cell line, Treatment
View SamplesMalignant mesothelioma (MM) is an asbestos-related malignancy and largely unresponsive to conventional chemotherapy or radiotherapy. Novel, more effective therapeutic strategies are needed for this fatal disease. We performed microarray analysis of MM using Affymetrix Human U133 Plus 2.0 array. Aberrant expression of the genes participating in semaphorin signaling were detected in malignant mesothelioma cells. All MM cells downregulated the expression of more than one gene for SEMA3B, 3F, and 3G when compared with Met5a, a normal pleura-derived cell line. In 12 of 14 epithelioid MM cells, the expression level of SEMA3A was lower than that in Met5a. An augmented expression of VEGFA was detected in half of the MM cells. The expression ratio of VEGFA/SEMA3A was significantly higher in the epithelioid MMs than in Met5a and the non-epithelioid MMs. Next, gene expression profiling for the polycomb and trithorax group genes revealed that expression of BAP1, the catalytic subunit of the polycomb repressive deubiquitinase complex, and many trithorax group genes was downregulated in MMs compared with the expression of the same genes in Met5a cells. Perturbation of the polycombtrithorax balance plays a significant role in the pathogenesis of malignant mesothelioma.
Frequent deletion of 3p21.1 region carrying semaphorin 3G and aberrant expression of the genes participating in semaphorin signaling in the epithelioid type of malignant mesothelioma cells.
Sex, Age, Specimen part, Cell line
View SamplesBirt-Hogg-Dube (BHD) syndrome is an autosomal dominant disorder characterized by hamartomas of skin follicles, cystic lung disease, and renal neoplasia. Affected individuals carry heterozygous mutations in Folliculin (FLCN), a tumor suppressor gene that becomes biallelically inactivated in kidney tumors by second-hit mutations. Similar to other factors implicated in kidney malignancies, Folliculin has been shown to modulate activation of mammalian target of rapamycin (mTOR). However, its precise in vivo function is largely unknown because germline deletion of Flcn results in early embryonic lethality in animal models. We here describe mice deficient in the newly characterized Folliculin-Interacting Protein 1 (Fnip1). In contrast to Flcn, Fnip1-/- mice develop normally, are not susceptible to kidney neoplasia, but display a striking pro-B cell block that is independent of mTOR activity. We show that this developmental arrest results at least in part from impaired V(D)J recombination and caspase-induced cell death, and that pre-recombined V(D)J and Bcl2 transgenes reconstitute pre-B and mature B cell populations respectively. We also demonstrate that conditional deletion of Flcn recapitulates the pro-B cell arrest of Fnip1-/- mice. Our studies thus demonstrate that the Flcn-Fnip complex deregulated in BHD syndrome is absolutely required for B cell differentiation and that it functions both through mTOR dependent and independent pathways. Overall design: RNASeq data for two pro-B cell subsets (fraction B and CC'') isolated from wt and Fnip1-/- mice
The folliculin-FNIP1 pathway deleted in human Birt-Hogg-Dubé syndrome is required for murine B-cell development.
Cell line, Subject
View SamplesC57BL/6 mice were infected with the GS strain of G. duodenalis and total RNA prepared from the duodenum on day 10. Age matched controls were compared using Affy chips to determine changes in gene expression induced by infection.
Transcriptomic analysis of the host response to Giardia duodenalis infection reveals redundant mechanisms for parasite control.
Age, Specimen part
View SamplesAlternative splicing and mRNA editing are known to contribute to transcriptome diversity. Although alternative splicing is pervasive and known to contribute to a variety of pathologies, including cancer, the genetic context for individual differences in isoform usage is still evolving. Similarly, although mRNA editing is ubiquitous and associated with important biological processes such as intracellular viral replication and cancer development, individual variations in and the genetic transmissibility of mRNA editing are equivocal. Here, we have used linkage analysis to show that both mRNA editing and alternative splicing are regulated by the macrophage genetic background and environmental cues. We show that distinct loci, potentially harboring variable splice factors, regulate the splicing of multiple transcripts. Additionally, we show that individual genetic variability at the Apobec1 locus results in differential rates of C-to-U(T) editing in murine macrophages; with mouse strains expressing mostly a truncated isoform of Apobec1 exhibiting lower rates of editing. As a proof of concept, we have used linkage analysis to identify 36 high confidence novel edited sites. These results provide a novel and complementary method that can be used to identify C-to-U editing sites in individuals segregating at specific loci and show that, beyond individual DNA sequence and structural changes, differential isoform usage and mRNA editing can contribute to intra-species genomic and phenotypic diversity. Overall design: Bone marrow derived macrophages (BMDM) from female AxB/BxA mice were left unstimulated or stimulated with IFNG/TNF, or CpG for 18 hrs or infected with infected with type II (Pru A7) for 8 hrs. The transcriptional response was then measured using the illumina RNA-seq protocol on an illumuna HiSeq 2000.
The genetic basis for individual differences in mRNA splicing and APOBEC1 editing activity in murine macrophages.
Age, Specimen part, Cell line, Treatment, Subject
View SamplesAnalysis of the genes and cellular signalling cascades mediating the response of SCN slices to vasoactive intestinal peptide (VIP). Primary goal was to find novel genes that may be involved in circadian phase shifting for further study. Promoter analysis of significantly regulated genes and gene ontology analysis would provide information into pathways VIP acts through in the SCN.
Vasoactive intestinal peptide controls the suprachiasmatic circadian clock network via ERK1/2 and DUSP4 signalling.
Specimen part
View SamplesA dataset for coordinated transcriptome analysis of the effect of ethanol on human embryonic cerebral slices in vitro and on the mouse embryonic cerebral cortex in a in vivo model.
Combined transcriptome analysis of fetal human and mouse cerebral cortex exposed to alcohol.
Time
View Samples