Tiny actors, great roles: microRNAs in p53's service.

In the course of the last several years, microRNAs (miRNAs) have become a focus of great interest, owing to their unsuspected important roles in the regulation of many critical biological processes. Not surprisingly, miRNAs are also turning out to be intimately involved in cancer, through either excessive or decreased activity. A series of recent studies reveal a close link between miRNAs and the p53 tumor suppressor: as a transcription factor, p53 controls the expression of specific miRs, and this additional capacity of p53 contributes to its biological activities. This review will discuss the recent studies and their implications.