Résumé:
The efficacy of the anticancer immunomodulatory agent cyclophosphamide (CTX) is based on the bacteria in the intestines. How and which relevant bacterial species are involved in tumor immunosurveillance, and their mechanism of action is unclear.
Here we have identified two bacterial species, Enterococcus hirae and Barnesiella intestinihominis which are involved during CTX therapy while E. hirae moved from the small intestine to secondary lymphoid organs and increased the intratumoral CD8 / Treg ratio, B. intestinihominis accumulated in the colon and promoted infiltration of IFN-γ-producing γδT cells in cancerous lesions. The immune sensor, NOD2, limited the immunosurveillance of cancer induced by CTX and the bioactivity of these microbes
The intervention of certain lactic acid bacteria could accentuate the effect of tumor immunosurveillance managed by the microbiota, however the percentage of dysbiosis is currently high.
Finally, E. hirae and B. intestinihominis, Immune responses of intestinihominis-specific memory Th1 cells selectively predicted longer progression-free survival in patients with advanced lung and ovarian cancer treated. By chemoimmunotherapy, E. hirae and B. intestinihominis represent valuable "oncomicrobiotics" enhancing the efficacy of the most common alkylating immunomodulatory compound.
