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Sample GSM1923044 Query DataSets for GSM1923044
Status Public on Mar 10, 2016
Title Tumor21
Sample type genomic
 
Channel 1
Source name glioblastoma tissue
Organism Homo sapiens
Characteristics clinical_subgroup: short-term survivor (STS)
tissue type: glioblastoma
Growth protocol Not applicable
Extracted molecule genomic DNA
Extraction protocol Tumor tissue was snap-frozen and stored at -80°C until further processing. DNA was extracted with the QIAmp DNA Mini Kit (Qiagen) from samples found eligible in terms of tumor cell content (>60%) and necrosis (<20%). Analyte concentration and quality were determined using the Nanodrop 2000 spectrophotometer (Thermo Scientific) and Bioanalyzer 2100 (Agilent). For enrichment of hypermethylated DNA fractions, Methyl-CpG-binding domain (MBD)-Fc protein was produced and MCIp performed as previously described (Schilling et al., Genomics 2007). Briefly, 75 µg of MBD-Fc protein was coupled to 50 µl SIMAG protein A magnetic beads (Chemicell) at 4°C overnight. After binding of 2 µg sonicated DNA, the DNA was eluted with increasing NaCl concentrations (300-1000 mM) using the MagnetoPure-Micro bead separator (Chemicell). Lowly and highly methylated DNA was eluted at the lowest and highest concentrations, respectively. DNA enrichment was monitored by real-time PCR targeting known unmethylated and methylated DNA regions.
Label Cy5
Label protocol Highly methylated glioblastoma and normal brain control DNA were labeled with Alexa Fluor 5 and Alexa Fluor 3, respectively.
 
Channel 2
Source name normal brain tissue
Organism Homo sapiens
Characteristics tissue type: normal brain
Growth protocol Not applicable
Extracted molecule genomic DNA
Extraction protocol Tumor tissue was snap-frozen and stored at -80°C until further processing. DNA was extracted with the QIAmp DNA Mini Kit (Qiagen) from samples found eligible in terms of tumor cell content (>60%) and necrosis (<20%). Analyte concentration and quality were determined using the Nanodrop 2000 spectrophotometer (Thermo Scientific) and Bioanalyzer 2100 (Agilent). For enrichment of hypermethylated DNA fractions, Methyl-CpG-binding domain (MBD)-Fc protein was produced and MCIp performed as previously described (Schilling et al., Genomics 2007). Briefly, 75 µg of MBD-Fc protein was coupled to 50 µl SIMAG protein A magnetic beads (Chemicell) at 4°C overnight. After binding of 2 µg sonicated DNA, the DNA was eluted with increasing NaCl concentrations (300-1000 mM) using the MagnetoPure-Micro bead separator (Chemicell). Lowly and highly methylated DNA was eluted at the lowest and highest concentrations, respectively. DNA enrichment was monitored by real-time PCR targeting known unmethylated and methylated DNA regions.
Label Cy3
Label protocol Highly methylated glioblastoma and normal brain control DNA were labeled with Alexa Fluor 5 and Alexa Fluor 3, respectively.
 
 
Hybridization protocol Oligoarray control targets and hybridization buffer (Agilent In Situ Hybridization Kit Plus) were added, and samples were applied to microarrays enclosed in Agilent SureHyb-enabled hybridization chambers. After hybridization, slides were washed sequential
Scan protocol Scanned on an Agilent G2505B scanner.
Images were quantified using Agilent Feature Extraction Software.
Description DNA was enriched for hypermethylated fractions by Methyl-CpG Immunoprecipitation (MCIp)
Data processing Scanning raw data were processed using the statistical environment R. Background correction and log2 transformation were performed according to the NormExp method with offset = 50 (Ritchie et al., Bioinformatics 2007). Intensity-based LOESS normalization was applied to rank-invariant probes and negative controls in order to reduce technical noise between samples (Tseng et al., Nucleic Acids Res 2001). For intra-array normalization, log-intensity ratios (M-value) and log-intensity averages (A-values) were scaled to have the same median-absolute value across the array.
 
Submission date Nov 02, 2015
Last update date Mar 10, 2016
Contact name Christel Herold-Mende
Organization name Heidelberg University Hospital
Department Department of Neurosurgery
Lab Experimental Neurosurgery
Street address Im Neuenheimer Feld 400
City Heidelberg
ZIP/Postal code 69117
Country Germany
 
Platform ID GPL9767
Series (1)
GSE74561 LOC283731 promoter hypermethylation prognosticates survival after radiochemotherapy in IDH1 wild-type glioblastoma patients

Data table header descriptions
ID_REF
VALUE Normalized log10 ratio (Cy5/Cy3) representing test/reference. For details: see data processing.

Data table
ID_REF VALUE
A_17_P00000030 -0.028386
A_17_P15006585 -0.084529
A_17_P15006586 -0.086946
A_17_P00000058 0.009086
A_17_P00000077 0.10101
A_17_P00000078 -0.107022
A_17_P00000079 0.232587
A_17_P15006611 0.676526
A_17_P15006612 0.488497
A_17_P00000131 0.46289
A_17_P00000132 0.311901
A_17_P00000133 0.447034
A_17_P15006642 0.783138
A_17_P00000171 0.035089
A_17_P15006648 0.141849
A_17_P00000172 0.008076
A_17_P15006650 0.007367
A_17_P15006651 0.015171
A_17_P15006652 -0.03661
A_17_P15006654 0.051641

Total number of rows: 199416

Table truncated, full table size 4733 Kbytes.




Supplementary file Size Download File type/resource
GSM1923044_cmc_251479117359_S01_ChIP_105_Dec08.txt.gz 57.7 Mb (ftp)(http) TXT
Processed data included within Sample table
Processed data are available on Series record

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