Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

DNA copy numbers of malignant glioma in culture

ABSTRACT: Therapeutic screening of potential anticancer agents relies on representative cancer models. In vitro cell culture models have been long questioned to be representative for human malignant glioma. Therefore, in the present study genomic profiles of both short-term (2 weeks; n=8) and long-term (6 and 12 weeks; n=3) primary cell cultures and spheroid cultures were compared with their parental malignant gliomas. Cancer genomic profiles were obtained by 6400 BAC array comparative genomic hybridization. In 7 out of 8 short-term primary cell cultures, the genomic profiles clustered further from their parental tumors than the spheroid cultures. In 4 out of 8 samples, the changes were substantial and included chromosomal regions associated with prognosis and therapeutic response. The average correlation coefficients between parental tumor profiles and spheroid profiles was 0.89 (range: 0.79 to 0.97), whereas those between parental tumors and cell cultures was 0.62 (range: 0.10 to 0.96). In 2 out of 3 primary cell cultures progressive genetic changes appeared at 6 and 12 weeks after initial preservation, whereas the spheroid cultures were genetically stable throughout. It is concluded that the cancer genomic profile of primary cell cultures from malignant glioma is inconsistent with the parental tumorâs profile already after 2 weeks with subsequent progressive genetic changes. Because malignant glioma spheroids are genetically stable, biological characteristics of the parental tumor are better reflected. This indicates that the spheroid model is better for therapeutic screening. Keywords: comparative genomic hybridization Two in vitro culture models (primary cell culture and organotypic spheroid culture) and their parental tumor were compared in whole-genome DNA copy number profile. Malignant glioma surgical specimens from 8 patients were divided in parental tumor (T), primary cell culture (C) and organotypic spheroid culture (S). After 2 weeks, genomic DNA was extracted from culture harvests. For 3 of 8 surgical specimens (patient 55, 58, 60) cultures were extended to 6 and 12 weeks to determine DNA copy number changes in time. Primary cell culture harvests at 2, 6 and 12 weeks were named C1, C2, C3 and organotypic spheroid cultures harvests at 2, 6 and 12 weeks were named S1, S2, S3.

ORGANISM(S): Homo sapiens

SUBMITTER: Philip De Witt Hamer

PROVIDER: E-GEOD-6042 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

ACCESS DATA

Similar Datasets

Project description:The small RNA, ArcZ (previously RyhA/SraH), was discovered in several genome-wide screens in Escherichia coli and Salmonella. Its high degree of genomic conservation, its frequent recovery by shotgun sequencing, and its association with the RNA chaperone, Hfq, identified ArcZ as an abundant enterobacterial âcoreâ small RNA of unknown function. Here, we report that ArcZ acts as a post-transcriptional regulator in Salmonella, repressing the mRNAs of the widely distributed sdaCB (serine uptake) and tpx (oxidative stress) genes, and of STM3216, a horizontally acquired methyl-accepting chemotaxis protein (MCP). Both sdaCB and STM3216 are regulated by sequestration of the ribosome binding site. In contrast, the tpx mRNA is targeted in the coding sequence (CDS), arguing that CDS targeting is more common than appreciated. Transcriptomic analysis of an arcZ deletion strain further argued for the existence of a distinct set of Salmonella loci specifically regulated by ArcZ. In contrast, increased expression of the sRNA altered the steady-state levels of >16% (â¥750) of all Salmonella mRNAs, and rendered the bacteria non-motile. Deep sequencing detected a dramatically changed profile of Hfq-bound sRNAs and mRNAs suggesting that the unprecedented degree of pleiotropic regulation might in part be caused by titration of Hfq binding by ArcZ. This study used three different approaches to identify target genes and biological role of the small RNA ArcZ in Salmonella Typhimurium. Transcriptomic analysis of ArcZ overexpression: Strain JVS-0082 (ÎarcZ) was transformed with plasmids pJV300 (control) and pKP48-1 (parcZ), and grown in liquid culture (LB broth) inoculated 1:100 from an overnight culture for 6h after cells had reached an OD600=2.0 to attain late stationary phase. Transcriptomic analysis of arcZ mutant strain: Strains JVS-007 (WT) and JVS-0082 (ÎarcZ) were transformed with plasmid pJV300 (control) and grown in liquid culture (LB broth) inoculated 1:100 from an overnight culture for 6h after cells had reached an OD600=2.0 to attain late stationary phase. Transcriptional effects of ArcZ pulse expression: Strain SL1344 was transformed with plasmids pKP8-35 (pBAD-control) and pKP4-13 (pBAD-ArcZ), and grown in liquid culture (LB broth) inoculated 1:100 from an overnight culture to an OD600 of 1.5. Expression of the insert was induced with L-arabinose (0.2% final concentrations) for 10 min. Three biological replicates were performed for each strain/condition.

Project description:Vitamin D is the strongest known natural anti-proliferative. A large number of studies in a wide spectrum of cancers, including epidemiological, in vitro and animal models, demonstrate that the active form of Vitamin D has anti-cancer benefits, affecting both progression and metastasis. Alike the role in calcium Vitamin D regulation, its anti-proliferative effect is thought to function through the Vitamin D receptor (VDR), although convincing evidence is lacking. Notwithstanding, separation of the calcemic and the anti-proliferative activity of Vitamin D analogues has been a major obstacle in developing new drugs for the treatment of cancer. The work presented attempts to unveil the molecular mechanism behind the anti-proliferative action of Vitamin D using genomic tools. For that purpose four independently developed Vitamin D sensitive/resistant MCF7 cell line pairs were collected. These unique biological replicates enabled us, both to increase the power of our study and to omit the use of Vitamin D. We deem this omission crucial since in the presence of Vitamin D only downstream genes involved in proliferation and cell cycle would be identified rather than causal resistance genes. The use of a variety of genomic techniques including expression, NMD and oligo CGH arrays reveal in the resistant cell lines the 11q13-14 as a region of DNA copy number loss and an altered expression of EGFR signaling pathway genes. Surprisingly, no genes known from calcium Vitamin D regulation were identified, nor did the VDR silencing by RNAi induce resistance to the sensitive cell lines. Keywords: comparative genomic hybridization, cell type comparision Several MCF7 breast tumor cell lines independently derived from the human breast cancer cell line, both resistant and sensitive to Vitamin D, were used. The pairs of cell lines (parental-resistant) were developed in different laboratories and using different methodologies; while some cell lines acquired resistance by long exposure to the physiological concentration of Vitamin D (100nM), others were induced to resistant by being exposed to increasing amounts of Vitamin D. A total of 4 microarray expression experiments were carried out. In all microarray experiments DNA from the Vitamin D resistant cell line was hybrizided agains DNA from the respsective sensitive/parental cell line.

Project description:Background: The molecular pathogenesis of small intestinal adenocarcinomas (SBA) is not well understood. Defining its molecular pathogenesis may lead us to better clinical interventions. Aim: to identify the molecular changes characteristic of SBA. Methods: Forty-eight SBA (thirty-three non coeliac disease (CD)-related and 15 CD-related) were characterized for chromosomal aberrations, by high resolution array comparative hybridization (aCGH), microsatellite status (MSI) and APC promoter methylation and mutation status. Furthermore, molecular alterations found in CD-related SBA were compared to non-CD related SBA. Results: Chromosomal changes were observed in 77% of the SBA. The most frequently (>10%) DNA copy number changes found were gains on 5p15.33-5p12, 7p22.3-7q11.21, 7q21.2-7q21.3, 7q22.1-7q34, 7q36.1, 7q36.3, 8q11.21-8q24.3, 9q34.11-9q34.3, 13q11-13q34, 16p13.3, 16p11.2, 19q13.2 and 20p13-20q13.33 and losses of 4p13-4q35.2, 5q15-5q21.1 and 21p11.2-21q22.11. Seven highly amplified regions on 6p21.1, 7q21.1, 8p23.1, 11p13, 16p11.2, 17q12-q21.1 and 19q13.2 were also identified. CD-related and non CD-related SBA displayed similar chromosomal aberrations. Promoter hypermethylation of the APC gene was found in 48% non CD-related and 73% CD-related SBA. No nonsense mutations were found. Last, 10% of the non CD-related SBA were MSI, whereas 43% of the CD-related SBA were MSI. Conclusions: Our study characterized specific chromosomal aberrations and amplifications involved in SBA pathogenesis. At the chromosomal level, CD-related and non CD-related SBA do not differ. The involvement of the MMR system in the pathogenesis of the CD-related SBA was larger than what has been observed in no CD-related SBA. No nonsense mutations were found in SBA, but frequent promoter methylation in CD-related SBA. Forty-eight SBA (thirty-three non coeliac disease (CD)-related and 15 CD-related) were characterized for chromosomal aberrations against a Human pool, by high resolution array comparative hybridization (aCGH),

Project description:Background Sex chromosomes are subject to evolutionary pressures distinct from the remainder of the genome, shaping their structure and sequence content. We are interested in the sex chromosomes of domestic pigs (Sus scrofa), how their structure and gene content compares and contrasts with other mammalian species, and the role of gonosomal genes in fertility. This requires an understanding of the XY-homologous sequence on these chromosomes. To this end, we performed microarray-based comparative genomic hybridisation (array-CGH) with male and female Duroc genomic DNA on a pig X-chromosome BAC tiling-path microarray. Putative XY-homologous BACs from regions of interest were subsequently FISH mapped. Results We show that the porcine PAR is approximately 6.5-6.9Mb at the beginning of the short arm of the X, with gene content reflective of the artiodactyl common ancestor. Our array-CGH data also shows an XY-homologous region close to the end of the X long arm, spanning three X BACs. These BACs were FISH mapped, and paint the entire long arm of SSCY. Further clones of interest revealed X-autosomal homology or regions containing repetitive content. Conclusions This study has identified regions of XY homology in the pig genome, and defined the boundary of the PAR on the X chromosome. This adds to our understanding of the evolution of the sex chromosomes in different mammalian lineages, and will prove valuable for future comparative genomic work in suids and for the construction and annotation of the genome sequence for the sex chromosomes. Our finding that the SSCYq repetitive content has corresponding sequence on the X chromosome gives further insight into structure of SSCY, and suggests further functionally important sequences remain to be discovered on the X and Y. Genomic DNA from male and female Duroc pigs were competitively hybridised to an X-chromosome BAC tiling-path microarray. Male DNA came from the animal used for Y chromosome sequencing at the Wellcome Trust Sanger Institute. Female DNA came from a fibroblast cell line. 4 hybridisations were performed. Clones with successful hybridisation in 2 or more of these replicates were used for analysis and detection of potential regions of XY homology.

Dataset Information

DNA copy numbers of malignant glioma in culture

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets