Autophagy: a strategy for malignant gliomas' resistance to therapy.

Gliomas are malignant primary brain tumors with high morbidity. This tumor has a feature of resistance to chemotherapy and radiotherapy and the underlying mechanism is not yet clear. Autophagy is an evolutionarily conserved process of cytoplasm and cellular organelle in lysosome degradation. Under poor conditions, cells use autophagy to recycle cellular components to sustain metabolism and to prevent the accumulation of damaged, toxic proteins and organelles. More and more recent experimental results suggest that autophagy allows tumor cells survive gene therapy, chemotherapy or nutrient deficient environment. Therefore, we propose the hypothesis that autophagy may be one of the factors influencing on malignant glioma's resistance to therapy. Although there is not yet reaching an agreement about the effects of autophagy on tumor cells survival and death and much more studies are needed to prove the effects of autophagy on malignant gliomas, it gives us a new direction to investigate the mechanism underlying therapy resistance of malignant gliomas.