STAT3 and cancer: Analysis of the 380 DE genes from the virus group in IPA suggest that the mechanisms of the host response to pathogen include both recognition and defense against the pathogen, and also the activation of apoptosis and inflammatory pathways: 1) canonical pathway analysis identified p53 signaling, RIG-I and STAT3 pathway, 2) downstream functional analysis predicts a wide range of immune responses, and 3) network analysis found a network with 3 central nodes of NF-κB, IRF1 and IRF7, surrounded by several up-regulated genes that are involved in various cancers.