Project description:Comparison of human embryonic stem cell transcriptome with universal RNA pool (10 human cell lines) to reveal hES cell-specific gene expression. Keywords: cell type comparison
Project description:We analyzed specific genes for DNA copy number variation in hepatoma cells and investigated whether these factors are related to liver cancer phenotype. Chromosome 20p, which includes the ligand for Notch pathways, Jagged1, was found to be amplified in several types of hepatoma cells. In conclusion, amplification of Jagged1 contributed to mRNA expression that activates the Jagged1-Notch signaling pathway in liver cancer and led to poor outcome.
Project description:We analyzed specific genes for DNA copy number variation in hepatoma cells and investigated whether these factors are related to liver cancer phenotype. Chromosome 20p, which includes the ligand for Notch pathways, Jagged1, was found to be amplified in several types of hepatoma cells. In conclusion, amplification of Jagged1 contributed to mRNA expression that activates the Jagged1-Notch signaling pathway in liver cancer and led to poor outcome. Comparative genomic hybridization arrays spotted with 1,440 bacterial artificial chromosome clones were used to assess copy number changes in 7 hepatoma cell lines and 2 non-hepatoma cell lines to identify chromosomal regions associated with the pathogenesis of liver cancer.
Project description:Comparison of control wild-type and Rb-/- prostate epithelial cell lines under untreated and serum-free conditions Keywords = prostate Keywords = epithelial Keywords: other
Project description:Transarterial chemoembolization or systemic chemotherapy with doxorubicin has been the treatment of choice for unresectable hepatocellular carcinoma (HCC) conferring the best survival benefit. However, HCC is notorious for its predisposition to develop therapeutic tolerance. Thus, Affymetrix microarray analysis was performed on doxorubicin-resistant hepatoma cells to identify the drug resistance-related genes. The RNA isolated from primary hepatoma cells and their doxorubicin-resistant counterparts, then subjected to Affymetrix microarray analysis to identify the differential expression profiles of drug resistance-related genes.
Project description:The endoplasmic reticulum (ER) is the site of secretory lipoprotein production and de novo cholesterol synthesis, yet little is known about how these activities are coordinated with each other, or with the activity of the COPII machinery, which transports ER cargo to the Golgi. The Sar1B component of this machinery is mutated in Chylomicron Retention Disorder, establishing that this Sar1 isoform secures delivery of dietary lipids into the circulation. We used microarrays to investigate the effect of overexpression of Sar1 isoforms and a constitutively active mutant form of Sar1B, Sar1B:H79G, on global gene expression in rat hepatoma cell line, McArdle RH7777 and identified a strong down-regulation of cholesterol biosynthetic gene mRNA expression in the Sar1B:H79G-, but not the wild-type Sar1A- or Sar1B-overexpressing cell lines.
Project description:Expression profiling the response to inhibition of DNA methylation and histone deacetylation. Comparison of expression in HepG2 cells treated with 5-aza-dC, Trichostatin A, both, or none (control) to change methylation and acetylation status. Background:DNA methylation and histone deacetylation are epigenetic mechanisms that play major roles in eukaryotic gene regulation. We hypothesize that many genes in the human hepatoma cell line HepG2 are regulated by DNA methylation and histone deacetylation. Treatment with 5-aza-2'-deoxycytidine (5-aza-dC) to inhibit DNA methylation with and/or Trichostatin A (TSA) to inhibit histone deacetylation should allow us to identify genes that are regulated epigenetically in hepatoma cells. Results:5-aza-dC had a much larger effect on gene expression in HepG2 cells than did TSA, as measured using Affymetrix® HG-U133A Plus 2.0 microarrays. The expression of 1504 probe sets was affected by 5-aza-dC (at p < 0.01), 535 probe sets by TSA, and 1929 probe sets by the combination of 5-aza-dC and TSA. 5-aza-dC treatment turned on the expression of 211 probe sets that were not detectably expressed in its absence. Expression of imprinted genes regulated by DNA methylation, such as H19 and NNAT, was turned on or greatly increased in response to 5-aza-dC. Genes involved in liver processes such as xenobiotic metabolism (CYP3A4, CYP3A5, and CYP3A7) and steroid biosynthesis (CYP17A1 and CYP19A1), and CCAAT element-binding proteins (CEBPA, CEBPB, and CEBPG) were affected by 5-aza-dC or the combination. Many of the genes that fall within these groups are also expressed in the developing fetal liver. Quantitative real-time RT-PCR assays confirmed selected gene expression changes seen in microarray analyses. Conclusions:Epigenetics play a role in regulating the expression of several genes involved in essential liver processes such as xenobiotic metabolism and steroid biosynthesis in HepG2 cells. Many genes whose expression is normally silenced in these hepatoma cells were re-expressed by 5-aza-dC treatment. Many genes that are expressed in the fetal liver are up-regulated by demethylation, indicating that DNA methylation is a major factor in restricting the expression of fetal genes during liver development. Keywords: comparison of treatments