Activated Ras requires autophagy to maintain oxidative metabolism and tumorigenesis

作者：Guo Jessie Yanxiang; Chen Hsin Yi; Mathew Robin; Fan Jing; Strohecker Anne M; Karsli Uzunbas Gizem; Kamphorst Jurre J; Chen Guanghua; Lemons Johanna M S; Karantza Vassiliki; Coller Hilary A; DiPaola Robert S; Gelinas Celine; Rabinowitz Joshua D; White Eileen^*

来源：Genes & Development, 2011, 25(5): 460-470.

DOI：10.1101/gad.2016311

• autophagy
• p62
• Ras
• cancer
• metabolism
• mitochondria

Autophagy is a catabolic pathway used by cells to support metabolism in response to starvation and to clear damaged proteins and organelles in response to stress. We report here that expression of a H-ras(V12) or K-ras(V12) oncogene up-regulates basal autophagy, which is required for tumor cell survival in starvation and in tumorigenesis. In Ras-expressing cells, defective autophagosome formation or cargo delivery causes accumulation of abnormal mitochondria and reduced oxygen consumption. Autophagy defects also lead to tricarboxylic acid (TCA) cycle metabolite and energy depletion in starvation. As mitochondria sustain viability of Ras-expressing cells in starvation, autophagy is required to maintain the pool of functional mitochondria necessary to support growth of Ras-driven tumors. Human cancer cell lines bearing activating mutations in Ras commonly have high levels of basal autophagy, and, in a subset of these, down-regulating the expression of essential autophagy proteins impaired cell growth. As cancers with Ras mutations have a poor prognosis, this "autophagy addiction'' suggests that targeting autophagy and mitochondrial metabolism are valuable new approaches to treat these aggressive cancers.

• 出版日期2011-3-1