The human intestinal microbiome is often referred to as a separate organ and plays vital roles in the host’s health, constitution, and nutrition. Moreover, the intestinal microbiome has significant influence on the host's overall health, such as the immune system. An individual’s lifestyle and the gut microbiome are in mutual interplay to each other. Disturbance of the composition of the microbiome is a decisive factor for the prevalence of certain diseases, such as diabetes and colorectal cancer (CRC).
CRC is the third most common cancer worldwide and the second most common cause of cancer death. The colons of patients with CRC have an overall reduced microbial diversity. Their microbiome is enriched with certain bacteria, such as Enterococcus faecalis, Fusobacterium nucleatum, and Bacteroides fragilis. These bacteria trigger the onset of CRC and enhance its progression through different mechanisms, such as binding to human receptor proteins and alteration of signal transduction pathways, interaction with and modulation of immune cells, and biofilm formation. Due to these microbial-driven mechanisms underlying CRC development, the intestinal microbiome is a major target for cancer therapies.
While genomic sequencing, big data analysis, and substantial microbial studies in animal models identified important drivers of CRC on the microbial level, mechanistic details are unknown due to the lack of high resolution structures. We therefore attempt to close this gap of knowledge to facilitate the development of new, personalized anticancer drugs.