Oleg Kuznetsov, Director, Institute of Biochemistry of Biologically Active Compounds, National Academy of Sciences of Belarus, associate professor of the Department of Microbiology, Virology and Immunology named after S.I. Gelberg, Grodno State Medical University, Candidate of Biological Sciences;
Vladimir Tsyrkunov, professor of the Department of Infectious Diseases, Grodno State Medical University, Doctor of Medical Sciences.

Summary.
The authors assessed the level of the microbiome involvement in the pre- and tumor growth process of the gastrointestinal tract. They showed the need to study the pathology of the gastrointestinal tract at the genetic level in conjunction with the persistence of microorganisms, whose proteins and metabolites interact with the genome, modifying it. They showed the role of opportunistic microflora in the regulation of the immune response in patients with colorectal cancer and changes in microbiocenosis in lesions of the large intestine, liver and pancreas, as well as its significance in carcinogenesis.
Keywords: gastrointestinal tract, microbiome, metabolism, carcinogenesis.
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