In cancer cells, dysregulation of the components of these signalling pathways, including loss- or gain-of-function mutations, amplifications and deletions, leads to uncontrolled proliferation (such as TP53, APC, KRAS, MYC and PI3K) and an imbalance in the redox state (such as NRF2, KEAP1; reviewed in refs. 22,25,27,28,30–32). The gene discussed is TP53; the disease is cancer.