The molecular machinery linking macroautophagy (autophagy hereafter) to apoptosis is still being elucidated. A recent study found that the transcription factor FOXO3/FOXO3A (forkhead box O3), which regulates autophagy, is itself regulated by basal autophagy to determine apoptosis sensitivity. Autophagy inhibition confers cell sensitivity to anti-cancer agents, and this effect is explained by the ability of FOXO3 to transactivate the pro-apoptotic gene BBC3/PUMA. Here, we discuss the possibility that FOXO3 acts as a cell surveillance mechanism to correct autophagy perturbations (i.e., autophagy inhibition), and confers apoptosis sensitization if this autophagy imbalance is not rectified.
Keywords: Apoptosis; CRISPR/Cas9; FOXO3; MDM2; PUMA; autophagy; homeostasis; transcription.