TP53 and cancer: Of these, 45 pathways were classified as human diseases, namely: 22 were related to cancer (e.g., microRNA in cancer; gastric cancer); 16 were classified as signal transduction (e.g., TGF-beta, VEGF, Ras and ErbB signaling pathways); 10 were classified as cellular processes (e.g., p53 signaling pathway; apoptosis; cell cycle and focal adhesion); and the other 9 pathways were classified as organismal class systems (nervous and endocrine systems) (Figure 2).