XIAP: inhibitor of two worlds

Autophagy is a catabolic mechanism that selectively eliminates long-lived proteins, aggregates and damaged organelles and is thereby fundamental in maintaining cellular homeostasis. As a prosurvival mechanism, autophagy is carefully regulated and its dysfunction is associated with cancer development. Work of Huang et al (2013) in this issue of The EMBO Journal identifies the apoptosis inhibitor XIAP as a novel repressor of autophagy-a function that significantly contributes to its tumorigenecity.