Microbiome and Human Cancer: Descriptive Literature Review

The term “microbiome” is defined as the community of all microorganisms and their metabolic byproducts within their environment. It also refers to the complete set of genetic material and the relationships between these microorganisms within a specific ecological setting throughout a certain period of time. The human microbiome profile develops from birth and remains relatively stable throughout adult life. The microbiota’s primary functions include involvement in the most essential processes of the body’s vital activity, such as the development of adaptive mechanisms, immune defense, physiological homeostasis, cognitive function, and regulation of energy resources within the body. Consequently, the microbiota plays a pivotal role in preserving equilibrium within the macroorganism itself and between the macroorganism and its environment. This article presents the findings of numerous scientific investigations that examine the impact of microbiota on the vital activity of tumors. These studies demonstrate that the microbiota can either accelerate or decelerate tumor growth, and in certain instances, the bacterial community does not contribute to the development of tumors. Tumors, characterized by the profound cellular changes resulting from the impairment of essential DNA mechanisms, create a specific environment that fosters bacterial colonization. In general, tumor tissue is known to have a higher bacterial load compared to normal tissue. Bacteria have been observed to produce certain metabolites that are subsequently used by tumor cells. Consequently, these bacteria and tumor cells compete directly for nutrients essential to their vital functions. The study examines the conditions underlying a particular scenario in which tumors and microbiota may interact. The review presents findings from studies that have sought to regulate intratumor microbes as a potential new target for anti-cancer therapy. This includes the use of bacterial platforms and fecal microbiota transplantation. Additionally, this study presents investigational findings concerning the use of microbiota in the treatment of acute respiratory viral infection, with a focus on chemotherapeutic and immunotherapeutic protocols. These findings corroborate the efficacy of microbiota-based interventions and concurrently highlight the potential for adverse complications.