Project description:Both spotted long oligonucleotide arrays and Affymetrix GeneChips were used to measure differential gene expression in two RNA samples (K562 erythroleukemia RNA and the Stratagene Universal Human Reference RNA). For Affymetrix technology, the two RNAs were analyzed separately. There are two replicates for K562 RNA (GSM4843 and GSM4844) and three for the Stratagene Universal reference (GSM4845-GSM4847). Two types of spotted long oligonucleotide arrays were used. These arrays were used to do two-color hybridizations to directly compare K562 and Universal reference RNAs. One array (GPL273) was made with probes from the Operon Human Genome Oligo Set Version 1. These arrays were used with unamplified cDNA probes (6 replicates, GSM4848-GSM4853), with aRNA probes produced by one round of T7 RNA polymerase-based amplification (6 replicates, GSM4854-GSM4859), and with aRNA probes produced by two rounds of amplification (2 replicates, GSM4860-GSM4861). Keywords: parallel sample
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
Project description:Both spotted long oligonucleotide arrays (GPL1384) and Affymetrix GeneChip arrays (GPL96) were used to analyze gene expression in six human head and neck squamous cell carinoma samples versus control samples or lymph node metastases of the same patients. Hybridizations of HG-U133A GeneChip arrays were performed using standard Affymetrix protocols and equipment. Before hybridization on DKFZ Operon 27k long oligonucleotide arrays, 2 µg RNA were amplified by one round of linear isothermal RNA amplification, followed by Cy-dUTP incorporation using Klenow fragment. Hybridizations were performed for 16 h at 42 °C in a GeneTAC Hybridization Station (Genomic Solutions) using UltraHyb hybridization buffer (Ambion). Hybridized microarrays were scanned at 5 µm resolution on a GenePix 4000B microarray scanner (Axon Instruments). Raw signal intensities from both platforms were normalized applying variance stabilization (W. Huber et al., Bioinformatics 18 Suppl 1, 2002). Expression ratios were compared for those genes represented in both array platforms. Keywords: parallel sample