The impact of tumor and gut microbiotas on cancer therapy: Beneficial or detrimental?

Cancer is a globally challenging health problem threatening mankind. Despite therapeutic advances in dealing with this malignancy, heterogeneous response and resistance to chemotherapeutic agents remain the hallmarks of cancer therapy. On the other hand, the involvement of the microbiota in affecting human health is well defined. An ever-growing body of evidence implicates the potential link between the microbiome and the efficacy of cancer therapies. Gut microbiota can modulate the metabolism of drugs in a number of ways. The presence of bacteria within the tumor environment can also impact the responses to cancer therapies; changing the chemical structure of chemotherapeutic drugs, affecting their activity, and local concentration. However, the underlying mechanisms by which gut and tumor microbial communities affect the response to cancer therapy are poorly understood and deciphering these mechanisms is of paramount importance. This review provides an overview of how gut and tumor microbiota might affect the efficacy of chemotherapy, radiotherapy, and immunotherapy and alleviate the adverse side effects of these therapies for the development of personalized and effective anticancer therapy.

Hekmatshoar Y ，Rahbar Saadat Y ，Hosseiniyan Khatibi SM ，Ozkan T ，Zununi Vahed F ，Nariman-Saleh-Fam Z ，Pourghassem Gargari B ，Sunguroglu A ，Zununi Vahed S ... -  《-》

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.

Chen W ，Wang S ，Wu Y ，Shen X ，Guo Z ，Li Q ，Xing D ... -  《-》

Human Microbiota and Personalized Cancer Treatments: Role of Commensal Microbes in Treatment Outcomes for Cancer Patients.

Gately S 《-》

[Gut microbiota and efficacy of cancer therapies].

The gut microbiota is known to affect digestion, protection against pathogens infection, immune system maturation and enteric nervous system development, but others links have also been established with diabetes, obesity, autism and cancer. Lately, bacterial species from the gut have been involved in tumor immunosurveillance. Natural or mediated by treatment such as chemotherapy or immunotherapy, anti-tumoral immune responses seem to rely on gut microbiota. The bacteria involved and their mechanisms of action are different according to the treatment of interest. Nevertheless, modulation of gut microbiota represents a great potential with the development of onco-micro-biotics to optimize the response to cancer therapies.

Vétizou M ，Daillère R ，Zitvogel L 《-》

Microbiota: a key orchestrator of cancer therapy.

Roy S ，Trinchieri G 《-》