Engaging the p53 metabolic brake drives senescence.

Emerging evidence suggests that the ability of p53 to regulate metabolism is important for its tumor suppressor activity. A recent study published in Nature reveals a novel connection between p53 and metabolism: p53 transcriptionally represses the expression of malic enzymes and associated NADPH production, which in turn triggers a positive feedback loop resulting in sustained p53 activation, cellular senescence, and tumor suppression.