  Genomic alterations lead to cancer complexity and form a major hurdle for a
comprehensive understanding of the molecular mechanisms underlying oncogenesis.
In this review, we describe the recent advances in studying cancer-associated
genes from a systems biological point of view. The integration of known cancer
genes onto protein and signaling networks reveals the characteristics of cancer
genes within networks. This approach shows that cancer genes often function as
network hub proteins which are involved in many cellular processes and form
focal nodes in the information exchange between many signaling pathways.
Literature mining allows constructing gene-gene networks, in which new cancer
genes can be identified. The gene expression profiles of cancer cells are used
for reconstructing gene regulatory networks. By doing so, the genes, which are
involved in the regulation of cancer progression, can be picked up from these
networks after which their functions can be further confirmed in the
laboratory.
