| Autophagy - Macroautophagy / Autophagic-Lysosomal Pathway
Abbreviation: Autophagy, Macroautophagy
Type: Cellular degradation pathway / lysosomal quality-control process
Function: Autophagy is a conserved cellular recycling pathway in which cytoplasmic proteins, damaged organelles, protein aggregates, and other cellular components are enclosed within autophagosomes and delivered to lysosomes for degradation. Major regulators include ULK1/ATG13, BECN1, VPS34, ATG5, ATG7, LC3, p62/SQSTM1, mTOR, and AMPK.
Cancer: ↕ Context-dependent. Autophagy can suppress tumor initiation by removing damaged organelles, limiting oxidative stress, and maintaining genomic stability. In established cancers, however, increased autophagy can support tumor-cell survival during hypoxia, nutrient deprivation, metabolic stress, and anticancer treatment and can contribute to treatment resistance. The biological effect therefore depends strongly on tumor type and disease stage.
Alzheimer's Disease: ↓ / impaired autophagic flux. Alzheimer's disease is characterized by dysfunction of the autophagic-lysosomal pathway, including impaired autophagosome maturation and lysosomal clearance. Defective autophagy contributes to accumulation of amyloid-β, phosphorylated tau, damaged mitochondria, and other abnormal proteins. Restoration of effective autophagic flux is generally considered neuroprotective.
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