Autophagy modulation in cancer

Autophagy is a highly conserved, finely regulated and lysosome-dependent biological process through which eukaryotic cells mobilize metabolites in response to nutrient deprivation and dispose of supernumerary or toxic cytoplasmic entities to ensure cellular quality control. In line with the notion that autophagy globally preserves cellular homeostasis, defects in the molecular machinery for autophagy generally favour malignant transformation. Conversely, proficient autophagic responses are often beneficial to developing tumours as they support the survival of malignant cells facing harsh microenvironmental conditions. Finally, the ability of neoplastic cells to undergo autophagy influences their susceptibility to anticancer immune responses in a context-dependent manner. Thus, although autophagy stands out as a major target to intercept cancer at multiple inflection points of the disease, one-size-fits-all approaches are inherently incapable of capturing the complex influence of autophagy on the cancer cell (immuno)biology as a whole. Further complicating this scenario, healthy cells, including tumour-targeting immune effectors, rely on autophagy for their maturation, survival and functions, and pharmacological autophagy inhibitors currently available for use in humans are intrinsically nonspecific. Here, we discuss the promise and limitations of targeting autophagy to limit malignant transformation, exacerbate cancer cell death as driven by conventional therapeutics and restore immunosurveillance in support of superior disease responses to immunotherapy.