Researchers from the European Molecular Biology Laboratory have analysed the global microbial signatures specific to colorectal cancer.
EMBL worked with the University of Trento and international collaborators to analyse the microbiome changes associated with colorectal cancer, and found that the disease-specific microbiome changes are consistent across seven countries on three continents despite environmental, dietary and lifestyle differences.
The influence of gut bacteria on colorectal cancer development
Colorectal cancer is the third most common cancer globally. While stomach cancer can be caused by a single bacterial species, Helicobacter pylori, it has been less clear what rolemicrobes play in the development of colorectal cancer.
The new study analysed multiple existing microbiome association studies of colorectal cancer, as well as newly generated data to establish the differences between the microbes in the gut of a colorectal cancer patient and the microbes in the gut of a healthy subject.
How were the global microbial signatures identified for colorectal cancer?
Georg Zeller from the European Molecular Biology Laboratory (EMBL) in Heidelberg, Germany, explained: “We used a rigorous machine learning analysis to identify microbial signatures for colorectal cancer. We validated these signatures in early cancer stages and in multiple studies, so they can serve as the basis for future non-invasive cancer screening.”
Nicola Segata from the University of Trento in Italy, added: “We not only established a panel of gut microbes associated with colorectal cancer across populations, but also found signatures in microbial metabolism that have similar predictive power. These will enable new research aiming at understanding how gut microbes may contribute causally to cancer development.”
How to modulate the microbiome
Zeller concluded:“Because our findings and those recently made by other researchers show new ways in which microbes might contribute to cancer development, they raise the question of how to modulate the microbiome, for example by preventing certain species from colonising our gut. But that’s very difficult!”