Subject(s)
Antineoplastic Agents, Immunological/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Calcium Channels, L-Type/metabolism , Drug Resistance, Neoplasm , Lymphoma, Large B-Cell, Diffuse/drug therapy , MicroRNAs/metabolism , Cyclophosphamide/therapeutic use , Doxorubicin/therapeutic use , Humans , Lymphoma, Large B-Cell, Diffuse/metabolism , Prednisone/therapeutic use , Rituximab/therapeutic use , Vincristine/therapeutic useABSTRACT
BACKGROUND: There is an increasing need in transcriptome research for gene expression data and pattern warehouses. It is of importance to integrate in these warehouses both raw transcriptomic data, as well as some properties encoded in these data, like local patterns. DESCRIPTION: We have developed an application called SQUAT (SAGE Querying and Analysis Tools) which is available at: http://bsmc.insa-lyon.fr/squat/. This database gives access to both raw SAGE data and patterns mined from these data, for three species (human, mouse and chicken). This database allows to make simple queries like "In which biological situations is my favorite gene expressed?" as well as much more complex queries like: <
Subject(s)
Database Management Systems , Databases, Genetic , Gene Expression Profiling/methods , Information Storage and Retrieval/methods , Internet , Software , Transcription Factors/genetics , Algorithms , Animals , Birds , Humans , Mice , User-Computer InterfaceABSTRACT
The production of high-throughput gene expression data has generated a crucial need for bioinformatics tools to generate biologically interesting hypotheses. Whereas many tools are available for extracting global patterns, less attention has been focused on local pattern discovery. We propose here an original way to discover knowledge from gene expression data by means of the so-called formal concepts which hold in derived Boolean gene expression datasets. We first encoded the over-expression properties of genes in human cells using human SAGE data. It has given rise to a Boolean matrix from which we extracted the complete collection of formal concepts, i.e., all the largest sets of over-expressed genes associated to a largest set of biological situations in which their over-expression is observed. Complete collections of such patterns tend to be huge. Since their interpretation is a time-consuming task, we propose a new method to rapidly visualize clusters of formal concepts. This designates a reasonable number of Quasi-Synexpression-Groups (QSGs) for further analysis. The interest of our approach is illustrated using human SAGE data and interpreting one of the extracted QSGs. The assessment of its biological relevancy leads to the formulation of both previously proposed and new biological hypotheses.
