Atg7 deficiency induces a microbiome-influenced immune response and suppresses tumor growth to inhibit intestinal tumorigenesis. Mus musculus

Here, we show that autophagy is activated in the intestinal epithelium in murine and human colorectal cancer and that the conditional inactivation of Atg7 in intestinal epithelial cells inhibits the formation of pre-cancerous lesions in Apc+/- mice by enhancing anti-tumor responses. The antibody-mediated depletion of CD8+ T cells showed that these cells are essential for the antitumoral responses mediated by the inhibition of autophagy. We show that Atg7 deficiency leads to intestinal dysbiosis and that the microbiota is required for anti-cancer responses. In addition, Atg7 deficiency resulted in a stress response accompanied by metabolic defects, AMPK activation and p53-mediated cell cycle arrest in tumor cells but not in normal tissue. This study reveals that the inhibition of autophagy within the epithelium may prevent the development and progression of colorectal cancer in genetically-predisposed patients. Overall design: 6 samples analyzed corresponding to 3 normal duodenum of Apc+/- mice and 3 normal duodenum of Apc+/-Atg7-/- mice.