Figure 3.

Tumor-supporting functions of autophagy

Once malignant transformation has occurred, autophagy is believed to promote tumor progression and resistance to therapy. Such tumor-supporting functions reflects the ability of autophagy to: (1) improve the resistance of cancer cells to endogenous conditions that normally provoke cell death, such as the detachment from the basal membrane, hypoxia and nutrient deprivation; (2) render transformed cells less sensitive to therapy-induced cell death; (3) sustain the survival of cancer cells that enter a state of dormancy or senescence in response to therapy; and (4) ensure the maintenance of the cancer stem cell compartment. EMT, epithelial-to-mesenchymal transition.