p53, named for its apparent molecular mass of 53 kilodaltons via SDS-PAGE analysis, is a protein that functions as a tumour suppressor and plays an important role in cell cycle regulation and cancer prevention. Over 50% of all cancers are theorized to involve p53-inactivating mutations. DNA damage, activated oncogenes, and oxidative stress can all produce stress signals to activate the p53 protein which is a transcriptional activator of >2500 p53-regulated genes. Activation of p53-regulated genes will lead to cellular senescence, cell cycle arrest, or apoptosis. Activated p53-regulated genes will also communicate with nearby cells for the purpose of DNA repair or feedback loop set-up that can either strengthen or weaken the stress responses of the p53 protein.

p53 Signaling Pathway References