Emergence of Bacterial Resistance to Antibiotics in the Digestive Microbiota of Patients Treated With Anticancer Drugs

Solid cancers are frequently treated with chemotherapies that target the DNA of cancer cells. It has recently come to light that bacteria are also the target of chemotherapies used in oncology. The results of current studies demonstrate the close link between the composition of the microbiota, the immune system, toxicity and the efficacy or otherwise of anti-cancer treatments. In this context, the study will measure the influence of treatment with anticancer molecules known to activate the bacterial SOS response on the emergence of antibiotic-resistant commensal bacteria in the gut microbiota of cancer patients. Furthermore, this study will investigate the existence of a close link between changes in the intestinal microbiota determined by the induction or non-induction of the SOS response, bacterial translocation, the integrity of the intestinal barrier and the antitumor immune response. The RAMA trial plans to collect stool and blood samples from two different cohorts of patients: * Unexposed cohort: patients receiving anti-cancer treatment that does not induce bacterial SOS response. * Exposed cohort: patients receiving anti-cancer treatment inducing the bacterial SOS response. Patients' stools will be collected within 7 days of their first chemotherapy treatment and within 7 days of the 3rd chemotherapy cycle. Two blood samples will be taken at the same time as the stool samples. The results obtained from this prospective clinical research will then be investigated in two experimental laboratory models. The aim is to demonstrate that cytotoxic anticancer drugs promote the emergence of antibiotic-resistant commensal bacteria, by means of this large-scale study comprising a clinical component, which is the subject of the research presented in this protocol, combined with laboratory research components.