<i>Fusobacterium nucleatum</i>—The Cause of Human Colorectal Cancer

Objective: Accumulating evidence indicates that the gut microbiome has an increasingly important role in human disease and health. Fusobacterium nucleatum has been identified in several studies as the leading gut bacterium which is present in colorectal cancer (CRC). Still it is not clear if Fusobacterium plays a causal role. Methods: To explore the cause-effect relationship between Fusobacterium nucleatum and colorectal cancer, a systematic review and re-analysis of studies published were performed. The method of the conditio sine qua non relationship was used to proof the hypothesis without Fusobacterium nucleatum infection, no colorectal cancer. The mathematical formula of the causal relationship k was used to proof the hypothesis, whether there is a cause-effect relationship between Fusobacterium nucleatum and colorectal cancer. Significance was indicated by a p-value of less than 0.05. Result: The data analyzed support the Null-hypothesis that without Fusobacterium nucleatum infection, no colorectal cancer. In the same respect, the studies analyzed provide highly significant cause-effect relationship between Fusobacterium nucleatum and colorectal cancer. Conclusion: The findings of this study suggest that Fusobacterium (nucleatum) is the cause of colorectal cancer.