Colorectal Cancer and the Role of Gut Microbiome

Colorectal cancer is one of the most common types of cancer, often diagnosed at advanced stages, limiting treatment options. This highlights the need for simpler and less invasive diagnostic tools, especially with an unexplained increase in cases among young people. Scientists have long known that the gut microbiome plays a role in the development of colorectal cancer, but translating this knowledge into clinical practice has been a significant challenge.

The Role of Microbiome in Colorectal Cancer

The gut microbiome plays a crucial role in many biological processes in the body, including digestion and immunity. However, its role in cancer development has started to attract researchers’ attention in recent years. The effects of different bacterial species vary greatly, with some strains contributing to disease development while others have little to no impact.

Professor Mirko Trajkovski from the University of Geneva explained that focusing on the intermediate level of the microbiome, known as subspecies, might be the solution. This level can capture differences in how bacteria function and affect diseases, including cancer, while remaining general enough to detect these changes among different groups of people, populations, or countries.

Analysis Using Machine Learning

Researchers have begun analyzing vast amounts of data using machine learning techniques. Led by PhD student Mateja Trikovic, the team developed the first comprehensive catalog of human gut microbiome subspecies. This catalog represents a significant step towards a deeper understanding of the microbiome and its use in diagnostics.

Using this catalog, scientists developed a model that can predict the presence of colorectal cancer based solely on the bacteria present in stool samples. The results were remarkable, with this method detecting 90% of cancer cases, approaching the 94% detection rate of colonoscopy.

Future Applications of This Discovery

The potential applications of this discovery extend beyond colorectal cancer. By studying the differences between bacterial subspecies, researchers can identify the mechanisms by which the gut microbiome affects human health. This method could soon be used to develop non-invasive diagnostic tools for a wide range of diseases, all based on a single microbiome analysis.

A clinical trial is currently being prepared in collaboration with the University of Geneva Hospitals to determine the cancerous stages and lesions that can be detected more accurately. This tool could become part of routine screenings for early detection of colorectal cancer.

Conclusion

Advancements in understanding the role of the gut microbiome in the development of colorectal cancer suggest the possibility of new, non-invasive diagnostic tools. These developments not only contribute to improved early cancer detection but also open new avenues for understanding how the gut microbiome affects overall health. Challenges remain, but there is great hope that this research will lead to significant improvements in clinical practices and healthcare.