The role of autophagy in regulating Tumour Necrosis Factor Receptormediated biological responses in normal and malignant epithelial cells

Autophagy (or type II programmed cell death, PCD), as opposed to apoptosis (or PCD type I), is characterized by excessive accumulation of autophagic vacuoles in the cytoplasm. This mediates destruction of cellular components and produces building blocks essential for cell survival. Yet, autophagy can also participate in the process of cell death, acting in parallel with apoptosis, or synergise with apoptosis by activating or amplifying death signals. Thus, autophagy appears to be able to have both cytoprotective properties but can also facilitate the process of cell death.