Personalized medicine is a strategy that takes into account differences in genes, environment, and lifestyle of each person for clinical decisions, practices, and interventions. In the past few decades, we have witnessed the arrival of microbiome research, a diverse community of microorganisms that live on and inside the human body which contributes 100 times more genes than the host and affects several physiological processes.
Changes in the gut microbiome can not only help to identify certain conditions, but may also predict the activity of a disease, how severe it is, and how it is responding to treatment. Bacterial dysbiosis has been widely associated with Crohn’s disease (CD). Patients with CD have decreased microbial diversity . Altering the microbial composition of the gut with targeted therapies such as probiotics, bacterial consortia, or even dietary manipulation can help to diversify the microbial community so that the balance of microbes is regulated to a beneficial level leading to an improvement to disease activity.
Moreover, the role of the human microbiome is becoming more apparent in response to cancer treatment, with proof suggesting that changing the gut microbiota community influence oncogenesis, tumor development and response to treatment. Therefore, understanding host–microbe interactions in patients may allow for more precise, faster, and less intrusive processes. Similarly, the diversity of the microbiome affects pharmacokinetic and pharmacodynamic processes through the secretion of enzymes that changes drug structure thus interfering with drug metabolism, alteration of human metabolic genes expression, and modification of intestinal and liver enzymes. Anticancer therapy can promote detrimental dysbiosis, which limits the effectiveness or makes the treatment more toxic, or beneficial dysbiosis, which increases the efficiency of the treatment.
Topotecan and irinotecan are chemotherapeutic agents that can cause severe diarrhea since they are glucuronidated into an inactive form by hepatic metabolism, but they undergo beta-glucuronidation into the active form by bacterial enzymes once they reach the gut. Using microbiome data to understand drug-microbiome interactions may help in recommending the appropriate medical treatment that is patient-tailored.
Understanding the microbiome structure of different diseases could facilitate its use in personalized disease diagnosis, as a precise, non-intrusive, and cost-effective tool that can help in the early detection of several disorders in the population. Potential therapeutic agents, dietary interventions, and reshaping of the gut microbiome represent a viable strategy in a time of personalized medicine.