DRAM Links Autophagy to p53 and Programmed Cell Death

Abstract

It is clear that changes in autophagy and autophagy regulators occur during tumor development and that this can have profound effects in certain tumor settings. The fact that p53, a key tumor suppressor mutated in approximately 50% of human cancers, has now also been shown to induce autophagy, has placed autophagy center stage in the minds of those interested in the development and treatment of malignant disease. p53 is a transcription factor that responds to cellular stress and prevents the propagation of cells which may otherwise form a tumor. The recent discovery, therefore, of DRAM (damage-regulated autophagy modulator) as a new p53 target which modulates autophagy is a major step forward in understanding how p53 controls autophagy and how this relates to tumor suppression. DRAM is a lysosomal protein that is not only critical for the ability of p53 to induce autophagy, but also for p53's ability to induce programmed cell death--a facet of p53 considered central to its tumor-suppressive effects. The fact that DRAM is also inactivated in certain cancers underscores its importance and highlights the possibility that autophagy may have a more profound role in cancer than was first believed.