The impact of the intestinal microbiota in therapeutic responses against cancer

Accumulating evidence points to the impact of the gut microbiota in regulating various chronic inflammatory disorders such as cancers. The intestinal microbiome is not only influencing the spontaneous course of colon malignancies but also acts at distant sterile sites of neoplasia, mostly playing a detrimental role. By providing microbial-associated molecular patterns and potentially antigens sharing molecular mimicry with tumor antigens, our commensals modulate the local and the systemic immune tonus, eventually influencing tumor microenvironment. Complicating this algorithm, therapeutic interventions alter the delicate balance between the epithelium, the microbial community, and the intestinal immunity, governing the final clinical outcome. This seminar focused on the impact of the intestinal composition on the immunomodulatory and therapeutic activities of distinct compounds (alkylating agents, platinum salts and immunotherapies) used in oncology. This research opens up “the era of anticancer probiotics” aimed at restoring gut eubiosis for a better clinical outcome in cancer patients.