Researchers have been working toward using the gut microbiome as a clinical target for screening for colorectal cancer. This would ideally allow simple stool tests to be used for early detection of the disease in place of expensive procedures such as colonoscopies. An international study that has just been published in Nature Medicine focused precisely on this subject.
Colorectal cancer is the third most frequent type of cancer and the second most lethal in the world, and only 40 percent of patients are diagnosed before metastasis. Experts are therefore focusing on improving its diagnostics.
An international research team coordinated by the University of Trento worked on the currently published study. A team of scientists has demonstrated that the presence of specific microbes in the microbiome is an accurate indication of the disease. The study – conducted using a combination of machine learning and metagenomics and published in Nature Medicine – could make non-invasive screening methods more accurate in the future. The study draws on newly collected gut microbiome data from six international cohorts, including two from the Czech Republic.
The study is part of major international projects involving research partners from all over the world: ONCOBIOME, funded by the European Commission, as well as two Cancer Grand Challenges teams (team PROSPECT, funded by Cancer Research UK, the National Cancer Institute, The Bowelbabe Fund for Cancer Research UK and The French National Cancer Institute, and team OPTIMISTICC, funded by Cancer Research UK).
Together, the two Czech cohorts contributed 328 newly sequenced samples, including 260 colorectal cancer cases—representing nearly 50% of all CRC samples in the new datasets. Their inclusion was critical in achieving the level of statistical power necessary for machine learning models to reach high predictive accuracy.
In the current study, experts examined over 1,600 newly sequenced samples, with the largest group of new colorectal cancer cases (204/525, more than 38%) provided by the Czech COLOBIOME cohort. This cohort was initiated by Dr. Eva Budinská from the RECETOX research institute at the Faculty of Science, Masaryk University, during her parallel affiliation with the Masaryk Memorial Cancer Institute (MMCI), where a prospective observational study was conducted under an AZV national grant. The samples were later integrated into the ONCOBIOME project, in which Dr. Budinská now serves as the principal investigator for the Czech Republic, thanks to the support of the MMCI’s Bank of Biological Material, which enabled long-term storage of the study biospecimens.
Together, the Czech groups represent the largest national share of the new study data and were essential for the development and validation of predictive models. “We are proud that the Czech cohorts played such a vital role in this study. Our COLOBIOME cohort provides one of the most comprehensive clinical resources to date, with detailed staging and tumor localization for over 200 patients. This depth of information significantly strengthened the study’s ability to link microbiome signatures with cancer progression,” says Eva Budinská.
Roman Hrstka, Director of the Bank of Biological Material at Masaryk Memorial Cancer Institute, added: “We are pleased that biospecimens provided by our biobank played a key role in such an impactful study. This is a clear example of how long-term investments into high-quality biobanking infrastructure can significantly contribute to international research efforts with direct clinical implications.”
More information can be found on the RECETOX website.