Live or let die: the cell's response to p53.

Compared with many normal tissues, cancer cells are highly sensitized to apoptotic signals, and survive only because they have acquired lesions - such as loss of p53 - that prevent or impede cell death. We are now beginning to understand the complex mechanisms that regulate whether or not a cell dies in response to p53 - insights that will ultimately contribute to the development of therapeutic strategies to repair the apoptotic p53 response in cancers.