The intestinal microbiota is a complex micro-ecological system symbiotic with human body, which has attracted increasing attention in recent years. The intestinal microbiota plays important roles not only in maintaining normal physiological functions of the human body but also in the occurrence, development, diagnosis and treatment of tumors. This review summarized the relationship between the intestinal microbiota and tumor, highlighting the mechanisms by which intestinal microbiota modulates tumor occurrence, development and immunotherapy, particularly the immune checkpoint therapy. This review also summarized the currently available methods for enhancing the efficacy of tumor therapy through regulation of intestinal microbiota. Challenges in the field as well as future perspectives were also discussed.
Keywords: immune checkpoint inhibitor; immunotherapy; intestinal microbiota; tumor.