Immunogenic cell death: A link between gut microbiota and anticancer effects

For years, intratumor injection of bacteria have been purported to be capable of an anticancer effect. However, these bacteria are mostly pathogenic including attenuated and genetically engineered bacteria. The gut microbiota has been discovered to play a key role in immunotherapy. Many remarkable advances have been made in characterizing the immune responses to gut microbiota. Interestingly, accumulating evidence has demonstrated that immunogenic cell death (ICD) plays a key role in the anticancer effect of chemotherapy, radiotherapy, photodynamic therapy and oncolytic virotherapy. Most interestingly, the gut microbiota may impact the ICD process. Given the importance of the gut microbiota in immune responses, cancer progression and the anticancer efficacy of drugs with immune effects. We propose a mechanism in which ICD may be the possible key link between gut microbiota and the anticancer efficacy of drugs with immune effects. However, the study of the relationship between the gut microbiota and ICD is limited, and it is still not clear how gut microbiota affect the ICD pathway. In this review, we discuss the mechanism by which the gut microbiota affects ICD, and suggest that ICD may be a possible key link between gut microbiota and the anticancer efficacy of drugs with immune effects.