Opinion - Integrated global profiling of cancer

Tumours are complex biological systems. No single type of molecular approach fully elucidates tumour behaviour, necessitating analysis at multiple levels encompassing genomics and proteomics. Integrated data sets are required to fully determine the contributions of genome alterations, host factors and environmental exposures to tumour growth and progression, as well as the consequences of interactions between malignant or premalignant cells and their microenvironment. The sheer amount and heterogeneous nature of data that need to be collected and integrated are daunting, but effort has already begun to address these obstacles.