Project description:These arrays are used for various projects Experiment Overall Design: HG-U133A and HG-U133B data are combined and analyzed together with other U133A & B or with HG-U133plus2 samples. No replicates were performed. Controls are human bronchial epithelial cells (HBECs)
Project description:The goal of this study is to identify those genes that are commonly silenced by DNA-methylation in lung cancer cell lines. Keywords: cell line comparison, stress response
Project description:Gene expression profile of squamous lung cancer cells are used to identify genes that are differentially regulated. Keywords: Cell type comparison
Project description:Hybridisations were carried out to define a fibroblast-like cell type derived from H9 human embryonic stem cells. Keywords: cell type comparison
Project description:Expression profiles of immortal esophageal squamous cancer cell lines were compared with those of cultured mortal noncancerous esophageal epithelial cells. Keywords: Cell type comparison
Project description:HEK-293-derived cell lines depleted of Dicer or one of four Argonaute proteins were generated. Microarray analysis of these knock down cell lines and various control cell lines was performed to address how large the proportion of genes is that are regulated by RNA silencing in an individual cell type. Comparison of different arrays revealed commonly (up) regulated genes. The highest overlap was observed in Ago2 and Dicer knockdown cells. Keywords: different timepoints of induction of stable knock down cell lines compared to various control cell lines
Project description:Gastric adenocarcinoma is one of the major malignancies worldwide. Gastric cell lines have been widely used as the model to study the genetics, pharmacology and biochemistry of gastric cancers. Here we describe a comprehensive survey of the gene expression profiles of 12 gastric carcinoma cell lines, using cDNA microarray with 43 000 clones. For comparison, we also explored the gene expression patterns of 15 cell lines derived from lymphoid, endothelial, stromal and other epithelial cancers. Expression levels of specific genes were validated through comparison to protein expression by immunohistochemistry using cell block arrays. We found sets of genes whose expression corresponds to the molecular signature of each cell type. In the gastric cancer cell lines, apart from genes that are highly expressed corresponding to their common epithelial origin from the gastrointestinal tract, we found marked heterogeneity among the gene expression patterns of these cell lines. Some of the heterogeneity may reflect their underlying molecular characteristics or specific differentiation program. Two putative gastric carcinoma cell lines were found to be B-cell lymphoma, and another one had no epithelial specific gene expression and hence was of doubtful epithelial origin. These cell lines should no longer be used in gastric carcinoma research. In conclusion, our gene expression database can serve as a powerful resource for the study of gastric cancer using these cell lines Set of arrays organized by shared biological context, such as organism, tumors types, processes, etc. Keywords: Logical Set
Project description:Reliable clinical tests for predicting cancer chemotherapy response are not available and individual markers failed to correctly predict resistance against anticancer agents. We hypothesized that gene expression patterns attributable to chemotherapy-resistant cells can be used as a classification tool for chemoresistance and provide novel candidate genes involved in anthracycline resistance mechanisms. We contrasted the expression profiles of 4 different human tumor cell lines of gastric, pancreatic, colon and breast origin and of their counterparts resistant to the topoisomerase inhibitors daunorubicin or doxorubicin. We also profiled the sensitive parental cells treated with doxorubicin for 24h. We interrogated Affymetrix HGU133A and U95A arrays independently. We applied two independent methods for data normalization and used Prediction Analysis of Microarrays (PAM) for feature selection. In addition, we established data sets related to drug resistance by using a “virtual array” composed of features represented on both types of oligonucleotide arrays. We identified 71 candidate genes associated with doxorubicine/daunorubicine resistance. To validate the microarray data, we also analyzed the expression of 12 selected genes by quantitative RT-PCR or immunocytochemistry, respectively. While the comparison of drug-sensitive versus drug-resistant cells yields candidates associated with drug resistance, the 24h treatment of sensitive parental cells produced a distinct transcriptional profile related to short-term drug effects. Keywords: cell type comparison