p53: a heavily dictated dictator of life and death.

In 2003, a p53-expressing adenovirus was approved as a cancer therapy drug in China. Consequently, there has been a surge in the need to understand the regulation of wild type p53 function in vivo. The majority of the progress made during the past two years has focused on the cellular factors and post-translational modifications that regulate the expression levels and activities of p53 in response to stress signals.