KDM5A Regulates a Translational Program that Controls p53 Protein Expression.

The p53 tumor suppressor pathway is frequently inactivated in human cancers. However, there are some cancer types without commonly recognized alterations in p53 signaling. Here we report that histone demethylase KDM5A is involved in the regulation of p53 activity. KDM5A is significantly amplified in multiple types of cancers, an event that tends to be mutually exclusive to p53 mutation. We show that KDM5A acts as a negative regulator of p53 signaling through inhibition of p53 translation via suppression of a subgroup of eukaryotic translation initiation genes. Genetic deletion of KDM5A results in upregulation of p53 in multiple lineages of cancer cells and inhibits tumor growth in a p53-dependent manner. In addition, we have identified a regulatory loop between p53, miR-34, and KDM5A, whereby the induction of miR-34 leads to suppression of KDM5A. Thus, our findings reveal a mechanism by which KDM5A inhibits p53 translation to modulate cancer progression.