Harnessing autophagy and its transcriptional regulation in tumorigenesis and neurodegeneration: Potential and existing therapeutic strategies

Autophagy is a fundamental cellular process that maintains homeostasis by degrading and recycling cellular components. As autophagy is essential for metabolizing damaged organelles and toxic substances, it plays a crucial role in both normal physiology and pathological conditions. However, autophagy has dual roles in both tumorigenesis and neurodegeneration. In cancer, autophagy can act as a tumor suppressor by clearing damaged components in early stages, but promotes tumor survival and growth in later stages, particularly under stress. In neurodegeneration, impaired autophagy is implicated in the disease progression of conditions such as Alzheimer's, Parkinson's, and Huntington's Disease, in which the failure to clear misfolded proteins and damaged organelles exacerbates disease pathology. This review is organized to cover the molecular machinery and transcriptional regulation of autophagy, its disease-specific subtypes, its dual roles in tumorigenesis and neurodegeneration, and the current pharmacological landscape for therapeutic targeting. Attention is given to pharmacological modulation of autophagy, including senolytic drugs that selectively eliminate senescent cells by exploiting their dependence on anti-apoptotic survival pathways, and small-molecule regulators targeting key pathways such as PI3K-AKT-mTOR (phosphoinositide 3-kinase/AKT/mechanistic target of rapamycin) and AMP-activated protein kinase (AMPK). Depending on the pathological context, these drugs are under development to either inhibit or induce autophagy. Additionally, we address the challenges and limitations in developing effective autophagy-targeting drugs, underscoring the need for further research to identify new compounds that can modulate cellular autophagic flux.