In colon cancer models, depletion of neutrophils led to increased number of bacteria in tumors and proliferation of tumor cells accompanied by increased tumor cell DNA damage and an inflammatory response mediated by interleukin‐17 (IL‐17),55 indicating that the intratumor microbiome is under the active surveillance of immune system and that the immune suppressive microenvironment may contribute to the colonization of bacteria. The gene discussed is IL17A; the disease is neoplasm.