----------------------------------------------------------------------- BIOINFORMATICS COLLOQUIUM College of Science George Mason University ----------------------------------------------------------------------- Biological Pathway and Network Analysis for Functional Interpretation of Large-Scale Omics Data Zhang-Zhi Hu Georgetown University Abstract: The last decade has seen rapid expansion of genomics, transcriptomics, proteomics and other "-omics" as applied to biomedical researches. However, making senses out of the deluge of omics data remains challenging and requires effective bioinformatics approaches for data integration, analyses, and interpretation, which has become an active area of bioinformatics research, and is crucial to the realization of full potentials that omics are hoped to bring. We took a protein-centric data integration and analysis approach and developed iProXpress bioinformatics system (http://pir.georgetown.edu/iproxpress/) for functional analysis of large-scale data, primarily from gene expression and proteomics studies. The system contains three major components: a data warehouse with information derived from over 90 databases, analytical tools for sequence analysis and functional annotation, and a graphical user interface for iterative and comparative function and pathway analysis. The system's unique features include its comprehensiveness of protein sequence coverage and annotation, high protein mapping rate of expression data including protein spliced forms, and its versatility of use on different types of omics data. We applied this approach to several cancer studies for identifying pathways and networks, including organelle biogenesis in melanocytes, signaling and metabolic pathways in hormone- or radiation-resistant breast cancer and other cells. Our studies highlight the need of functional profiling, pathway/network analysis coupled with expert-guided examination for omics data interpretation and for hypothesis formulation.