Most Autophagic Cell Death Studies Lack Evidence of Causality

Autophagy plays a critical role in maintaining cellular homeostasis and is implicated in various physiological and pathological processes, including cancer, neurodegeneration, and metabolic disorders. Although typically associated with cell survival, autophagy has also been proposed to contribute to cell death, referred to as autophagic cell death (ACD). Despite its importance, the identification of ACD remains contentious due to inconsistencies in experimental methodologies and terminological misuse. In this study, we evaluated 104 research articles published in 2022 that claimed to demonstrate ACD. Articles were assessed based on established criteria, including evidence for autophagy, evidence for cell death, exclusion of apoptosis, and experimental designs demonstrating causality. Our findings reveal that only 12.5% of the articles fulfilled all the criteria for ACD, while 37.5% provided only correlation-level evidence. Additionally, 32.7% of the articles relied on viability loss rather than direct evidence of cell death, and 45.0% of studies utilizing autophagy inhibition to prove causality failed to demonstrate actual inhibition of autophagy. Inconsistent terminology was also prevalent, with cases of ‘autophagy-mediated cell death’ being incorrectly classified as ACD and instances where the term ACD was misused as an umbrella term to describe the coexistence of autophagy and cell death, which should have been labeled ‘autophagy-associated cell death.’ These issues highlight a lack of rigor in current practices, with reliance on correlation-level evidence and inappropriate experimental designs undermining the robustness of many studies. This analysis underscores the need for greater rigor in experimental approaches and article revision processes.