Project description:RATIONALE: Studying the genes expressed in samples of tissue from patients with cancer may help doctors identify biomarkers related to cancer.
PURPOSE: This laboratory study is using gene expression profiling to evaluate normal tissue and tumor tissue from patients with colon cancer that has spread to the liver, lungs, or peritoneum.
Project description:We examined tissue specificity of gene expression in control mussels. Total RNA was isolated from gills (G), digestive gland (DG), tissues involved in contraction/motility (FML: foot/adductor muscles/ligaments) and reproduction (GM: gonads and mantle) producing four tissue-specific samples. Total RNA was reverse-transcribed and labeled using a Cy3-dCTP and Cy5-dCTP direct incorporation. Each sample was hybridized in competition with the total pool (equal RNA amounts from G, DG, GM and FML) and the relative abundance of each gene was measured by directly comparing fluorescent signals for each probe. We reversed labeling of pool tissues (reference) and single tissue sample in each experiment, thus carrying out two separate hybridizations for each tissue. Keywords = mussels Keywords = tissue specificity Keywords = normal conditions Keywords = gene expression profiling Keywords: ordered
Project description:Our understanding of disease is increasingly informed by changes in gene expression between normal and abnormal tissues. The release of the canine genome sequence in 2005 provided an opportunity to understand health and disease in the dog using investigative techniques including gene expression profiling. Accordingly, we now present a publicly accessible canine normal tissue gene expression database that will streamline the study of canine tissues and facilitate comparative genomic analysis with other mammals. The Affymetrix platform was utilized to catalogue the genetic signatures of normal canine tissues including: liver, kidney, heart, lung, cerebrum, lymph node, spleen, jejunum, pancreas and skeletal muscle. The quality of the database was assessed in several ways. Organ defining gene sets were identified for each tissue and functional enrichment analysis revealed themes consistent with known physio-anatomic functions for each organ. In addition, a comparison of orthologous gene expression between matched canine and human normal tissues uncovered remarkable similarity. Public access and use of this data, using infrastructure identical to that currently in use for human normal tissues, has been established and allows for additional cross-species comparisons. To demonstrate the utility of this dataset, novel canine gene annotations were established based on comparative analysis of dog and human tissue selective gene expression and manual curation of canine probeset mapping. It is expected that this dataset will contribute to more advanced study of disease in the dog and biologically robust biomedical studies that utilize the dog as a model for translational research.
Project description:We performed expression profiling of 36 types of normal human tissues and identified 2,503 tissue-specific genes. We then systematically studied the expression of these genes in cancers by re-analyzing a large collection of published DNA microarray datasets. Our study shows that integration of each gene's breadth of expression (BOE) in normal tissues is important for biological interpretation of the expression profiles of cancers in terms of tumor differentiation, cell lineage and metastasis. Twenty five total RNA specimens were purchased from Clontech (Palo Alto, CA), Ambion (Austin, TX) and Strategene (La Jolla, CA). We tried to cover as many tissue types as possible by using pooled RNA samples. In order to define breadth-of-expression (BOE) accurately at a reasonable cost, we tried to cover as many tissue types as possible by using pooled RNA samples. Each specimen represents a human organ. We used RNA samples pooled from 2 to 84 donors to avoid differences at the individual level. Keywords = Normal human tissues Keywords = Tissue-specificity Detailed sample information and Affymetrix .CEL files are available at http://www.genome.rcast.u-tokyo.ac.jp/normal/ Publication:Ge X et al., Interpreting expression profiles of cancers by genome-wide survey of breadth of expression in normal tissues. Genomics. 2005 Aug;86(2):127-141. PMID: 15950434 Keywords: other