Human Bacterial Microflora Composition: Genotoxic and Carcinogenic Effects Associated with Its Changes in Various Organs

Abstract

The bacterial microflora that inhabits our body makes up the most complex microbial community called microbiota. The microbiota, which is evolutionarily fixed in the human body, has a significant effect on the maintenance of human health and functions. The study of the genotoxic potential of microflora, closely related to bacterial oncogenesis, remains incomplete. When the imbalance of healthy microflora is violated under the influence of various factors, including mutagens and environmental carcinogens, the composition of the microbiota is transformed into an aggressive form. It has been suggested that such changes lead to functional metabolism shifts in bacterial communities, which leads to a progression of malignant growth in these parts of the host organism. Bacteria are able to influence pathogenic processes occurring during the course of the disease, producing effectors of DNA damage in the cells of the host organism or modifying the body’s ability to metabolize mutagens and carcinogens. We present in this work evidence and hypotheses about the ability of pathogenic and commensal bacteria with genotoxic potential to lead to the development of oncological diseases. This paper examines individual organs (intestines, stomach, respiratory tract, gallbladder and mammary gland), whose carcinogenesis is influenced by bacteria that can damage the DNA of the host cells.