Identification of novel, highly penetrant, breast cancer susceptibility genes will require the application of additional strategies beyond that of traditional linkage and candidate gene approaches. Approximately one-third of inherited genetic diseases, including breast cancer susceptibility, are caused by frameshift or nonsense mutations that truncate the protein product [1]. Transcripts harbouring premature termination codons are selectively and rapidly degraded by the nonsense-mediated mRNA decay (NMD) pathway. Blocking the NMD pathway in any given cell will stabilise these mutant transcripts, which can then be detected using gene expression microarrays. This technique, known as gene identification by nonsense-mediated mRNA decay inhibition (GINI), has proved successful in identifying sporadic nonsense mutations involved in many different cancer types. However, the approach has not yet been applied to identify germline mutations involved in breast cancer. We therefore attempted to use GINI on lymphoblastoid cell lines (LCLs) from multiple-case, non-BRCA1/2 breast cancer families in order to identify additional high-risk breast cancer susceptibility genes.
No associated publication
Sex, Cell line
View Samples63 melanoma cell lines hybridized to Affymetrix Hu133_Plus 2 oligo arrays. The aim of this study was to identify potential downstream targets of key oncogenes and TSGs in melanoma (including p14ARF, p16INK4A, BRAF etc).
Confirmation of a BRAF mutation-associated gene expression signature in melanoma.
No sample metadata fields
View Samples35 Melanoma cell lines hybridized to Affymetrix Hu133_Plus 2 microarrays were analysed for genes differentially expressed between cell lines carrying wild-type p14ARF and those with mutant 14ARF. All of these cell lines contained wild-type p53 (so that the effects of p14ARF mutations could be analysed without contamination from p53).
Gene expression profiling in melanoma identifies novel downstream effectors of p14ARF.
No sample metadata fields
View SamplesTumor suppressor genes (TSGs) are sometimes inactivated by transcriptional silencing through promoter hypermethylation. To identify novel methylated TSGs in melanoma, we carried out global mRNA expression proling on a panel of 12 melanoma cell lines treated with a combination of 5-Aza-2-deoxycytidine (5AzadC) and an inhibitor of histone deacetylase, Trichostatin A. Reactivation of gene expression after drug treatment was assessed using Illumina whole-genome microarrays. After qRT-PCR conrmation, we followed up 8 genes (AKAP12, ARHGEF16, ARHGAP27, ENC1, PPP1R3C, PPP1R14C, RARRES1, and TP53INP1) by quantitative DNA methylation analysis using mass spectrometry of base-specic cleaved amplication products in panels of melanoma cell lines and fresh tumors. PPP1R3C, ENC1, RARRES1, and TP53INP1, showed reduced mRNA expression in 3559% of the melanoma cell lines compared to melanocytes and which was correlated with a high proportion of promoter methylation (>4060%). The same genes also showed extensive promoter methylation in 625% of the tumor samples, thus conrming them as novel candidate TSGs in melanoma.
Identification of candidate tumor suppressor genes inactivated by promoter methylation in melanoma.
Disease, Disease stage, Cell line, Treatment
View SamplesThe pathological outcomes of schistosomiasis are largely dependent on the molecular and cellular mechanisms of the host immune response. In this study, we demonstrate the variation of host gene expression which underlies the contrasting hepatic pathology observed between two inbred mouse strains following schistosome infection. Whole genome microarray analysis was employed in conjunction with histological and immunohistochemical analysis to define and compare the hepatic gene expression profiles and cellular composition associated with the hepatopathology observed in BALB/c and CBA mice during an active Schistosoma japonicum infection. Here, we show that the transcriptional profiles differ significantly between the two mouse strains with high statistical confidence. We identified specific genes correlating with the more severe pathology associated with CBA mice, as well as genes which may confer the milder degree of pathology associated with BALB/c mice. Generally, up-regulated genes were largely associated with immune and inflammatory responses, antigen processing and cytokine/chemokine activity. In BALB/c mice, neutrophil genes exhibited striking increases in expression, which coincided with significantly greater accumulation of neutrophils at granulomatous regions, compared to CBA mice. In contrast, up-regulated expression of eosinophil chemokine CCL24 in CBA mice paralleled the cellular influx of eosinophils to the hepatic granulomas. Additionally, there was greater down-regulation of genes involved in metabolic processes in CBA mice, reflecting the greater degree of liver damage in these mice. Genes involved in fibrosis showed similar levels of expression in both mouse strains. Genes associated with Th1 and Th2 responses showed no significant differences in expression between strains. These results provide a more complete picture of the molecular and cellular mechanisms which govern the pathological outcome of hepatic schistosomiasis. Furthermore, this improved understanding of schistosome immunopathogenesis in the murine model will provide the basis for a better appreciation of the complexities associated with chronic human schistosomiasis.
Differential expression of chemokine and matrix re-modelling genes is associated with contrasting schistosome-induced hepatopathology in murine models.
Sex, Age, Specimen part, Time
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Postnatal growth restriction and gene expression changes in a mouse model of fetal alcohol syndrome.
Sex, Specimen part
View SamplesExpression profiles of 17 melanoma cell lines were analysed to identify genes differentially expressed between cell lines harbouring wild-type or mutant p16INK4A. Relevant paper: Pavey et al. (2007). Note: all of these cell lines contained wild-type p14ARF, so that the transcriptional effects of p16INk4A could be determined without interference from p14ARF.
No associated publication
No sample metadata fields
View SamplesGrowth restriction, craniofacial dysmorphology and central nervous system defects are the main diagnostic features of fetal alcohol syndrome. Studies in humans and mice have reported that the growth restriction can be prenatal and/or postnatal, but the underlying mechanisms remain unknown. We recently described a mouse model of moderate gestational ethanol exposure that produces measurable phenotypes in line with fetal alcohol syndrome, e.g. craniofacial changes and growth restriction in adolescent mice. Here we further characterize the growth restriction phenotype by measuring body weight at gestational day 16.5, cross-fostering from birth to weaning, and extending our observations into adulthood. Furthermore, in an attempt to unravel the molecular events contributing to the growth phenotype, we have compared gene expression patterns in the liver and kidney of non-fostered ethanol-exposed and control mice at postnatal day 28. We find that the ethanol-induced growth phenotype is not detectable prior to birth, but is present at weaning, even in mice that have been cross-fostered to unexposed dams. This suggests a postnatal growth restriction phenotype that is not due to deficient postpartum care by dams that drank ethanol, but rather a physiological result of ethanol exposure in utero. We also find that, despite some catch-up growth after five weeks of age, the effect extends into adulthood, consistent with longitudinal studies in humans. Genome-wide gene expression analysis revealed interesting ethanol-induced changes in the liver, including genes involved in the metabolism of exogenous and endogenous compounds, iron homeostasis and lipid metabolism.
Postnatal growth restriction and gene expression changes in a mouse model of fetal alcohol syndrome.
Sex, Specimen part
View SamplesSchistosomiasis continues to be an important cause of parasitic morbidity and mortality world-wide. Determining the molecular mechanisms regulating the development of granulomas and fibrosis will be essential for understanding how schistosome antigens interact with the host environment. We report here the first whole genome microarray analysis of the murine liver during the progression of Schistosoma japonicum egg-induced granuloma formation and hepatic fibrosis. Our results reveal a distinct temporal relationship between the expression of chemokine subsets and the recruitment of cells to the infected liver. Genes up-regulated earlier in the response included T- and B-cell chemoattractants, reflecting the early recruitment of these cells illustrated by flow cytometry. The later phases of the response corresponded with peak recruitment of eosinophils, neutrophils, macrophages and myofibroblasts/hepatic stellate cells (HSCs) and the expression of chemokines with activity for these cells including CCL11 (eotaxin 1), members of the Monocyte-chemoattractant protein family (CCL7, CCL8, CCL12) and the Hepatic Stellate Cell/Fibrocyte chemoattractant CXCL1. Peak expression of macrophage chemoattractants (CCL6, CXCL14) and markers of alternatively-activated macrophages (e.g. Retnla) during this later phase provides further evidence of a role for these cells in schistosome-induced pathology. Additionally, we demonstrate that CCL7 immunolocalises to the fibrotic zone of granulomas. Furthermore, striking up-regulation of neutrophil markers and the localisation of neutrophils and the neutrophil chemokine S100A8 to fibrotic areas suggests the involvement of neutrophils in S. japonicum-induced hepatic fibrosis. These results further our understanding of the immunopathogenic and, especially, chemokine signalling pathways that regulate the development of S. japonicum-induced granulomas and fibrosis and may provide correlative insight into the pathogenesis of other chronic inflammatory diseases of the liver where fibrosis is a common feature.
Temporal expression of chemokines dictates the hepatic inflammatory infiltrate in a murine model of schistosomiasis.
Sex, Age, Specimen part, Treatment
View SamplesGrowth restriction, craniofacial dysmorphology and central nervous system defects are the main diagnostic features of fetal alcohol syndrome. Studies in humans and mice have reported that the growth restriction can be prenatal and/or postnatal, but the underlying mechanisms remain unknown. We recently described a mouse model of moderate gestational ethanol exposure that produces measurable phenotypes in line with fetal alcohol syndrome, e.g. craniofacial changes and growth restriction in adolescent mice. Here we further characterize the growth restriction phenotype by measuring body weight at gestational day 16.5, cross-fostering from birth to weaning, and extending our observations into adulthood. Furthermore, in an attempt to unravel the molecular events contributing to the growth phenotype, we have compared gene expression patterns in the liver and kidney of non-fostered ethanol-exposed and control mice at postnatal day 28. We find that the ethanol-induced growth phenotype is not detectable prior to birth, but is present at weaning, even in mice that have been cross-fostered to unexposed dams. This suggests a postnatal growth restriction phenotype that is not due to deficient postpartum care by dams that drank ethanol, but rather a physiological result of ethanol exposure in utero. We also find that, despite some catch-up growth after five weeks of age, the effect extends into adulthood, consistent with longitudinal studies in humans. Genome-wide gene expression analysis revealed interesting ethanol-induced changes in the liver, including genes involved in the metabolism of exogenous and endogenous compounds, iron homeostasis and lipid metabolism.
Postnatal growth restriction and gene expression changes in a mouse model of fetal alcohol syndrome.
Sex, Specimen part
View Samples