RB1 and cancer: The observation that several manipulations simultaneously modulate longevity and cancer protection establishes an interesting parallel with the expression of members of the Ink4/Rb and Arf/p53 pathways, which are silent or very low during development and postnatal life, while progressively increase from adulthood to old age in a broad range of tissues and species (Zindy et al., 1997; Krishnamurthy et al., 2004).