The gut microbiota and traditional Chinese medicine: a new clinical frontier on cancer.

Gut microbiota is a complex microecosystem which is called the second genome of the human body. Herbal medicine can balance tumor-suppressing bacteria and tumor-promoting bacteria and exert its anti-cancer effect by regulating gut microbiota. Traditional Chinese medicine (TCM) has a history of thousands of years in prevention and treatment of diseases in China. In recent decades, TCM show an obvious advantage in prolonging the survival time and improving the living quality of patients with cancer. Notably, gut microbiota has become a new pathway to understanding TCM. In this review, we will focus on gut microbiota and tumor progression, especially the diversity, functionality and metabolites of gut microbiota affected by TCM in various cancer. We will also discuss the potential mechanism of gut microbiota for exploring TCM in anti-cancer effect. This article aims to comprehensively review the anti-cancer research of TCM by regulating gut microbiota, and address future perspectives and challenges of gut microbiota in TCM intervention for cancer.