Clinical Applications of Autophagy Proteins in Cancer: From Potential Targets to Biomarkers.

Autophagy, a lysosome-mediated intracellular degradation and recycling pathway, plays multiple context-dependent roles in tumorigenesis and treatment resistance. Encouraging results from various preclinical studies have led to the initiation of numerous clinical trials with the intention of targeting autophagy in various cancers. Accumulating knowledge of the particular mechanisms and players involved in different steps of autophagy regulation led to the ongoing discovery of small molecule inhibitors designed to disrupt this highly orchestrated process. However, the development of validated autophagy-related biomarkers, essential for rational selection of patients entering clinical trials involving autophagy inhibitors, is lagging behind. One possible source of biomarkers for this purpose is the autophagy machinery itself. In this review, we address the recent trends, challenges and advances in the assessment of the biomarker potential of clinically relevant autophagy proteins in human cancers.