The Challenge of ICIs Resistance in Solid Tumours: Could Microbiota and Its Diversity Be Our Secret Weapon?

The human microbiota and its functional interaction with the human body were recently returned to the spotlight of the scientific community. In light of the extensive implementation of newer and increasingly precise genome sequencing technologies, bioinformatics, and culturomic, we now have an extraordinary ability to study the microorganisms that live within the human body. Most of the recent studies only focused on the interaction between the intestinal microbiota and one other factor. Considering the complexity of gut microbiota and its role in the pathogenesis of numerous cancers, our aim was to investigate how microbiota is affected by intestinal microenvironment and how microenvironment alterations may influence the response to immune checkpoint inhibitors (ICIs). In this context, we show how diet is emerging as a fundamental determinant of microbiota's community structure and function. Particularly, we describe the role of certain dietary factors, as well as the use of probiotics, prebiotics, postbiotics, and antibiotics in modifying the human microbiota. The modulation of gut microbiota may be a secret weapon to potentiate the efficacy of immunotherapies. In addition, this review sheds new light on the possibility of administering fecal microbiota transplantation to modulate the gut microbiota in cancer treatment. These concepts and how these findings can be translated into the therapeutic response to cancer immunotherapies will be presented.

Roberto M ，Carconi C ，Cerreti M ，Schipilliti FM ，Botticelli A ，Mazzuca F ，Marchetti P ... -  《Frontiers in Immunology》

Modulation of Gut Microbiota to Enhance Effect of Checkpoint Inhibitor Immunotherapy.

Accumulating evidence demonstrated the crucial role of gut microbiota in many human diseases, including cancer. Checkpoint inhibitor therapy has emerged as a novel treatment and has been clinically accepted as a major therapeutic strategy for cancer. Gut microbiota is related to cancer and the effect of immune checkpoint inhibitors (ICIs), and supplement with specific bacterial species can restore or enhance the responses to the ICIs. Namely, specified bacteria can serve as the biomarkers for distinguishing the patient who will respond to ICIs and determine the effectiveness of ICIs, as well as predicting the efficacy of checkpoint inhibitor immunotherapy. Regardless of the significant findings, the relationship between gut microbiota and the effect of ICIs treatment needs a more thorough understanding to provide more effective therapeutic plans and reduce treatment complication. In this review, we summarized the role of gut microbiota played in immune system and cancer. We mainly focus on the relationship between gut microbiota and the checkpoint inhibitor immunotherapy.

Wu J ，Wang S ，Zheng B ，Qiu X ，Wang H ，Chen L ... -  《Frontiers in Immunology》

The Role of Gut Microbiota in Overcoming Resistance to Checkpoint Inhibitors in Cancer Patients: Mechanisms and Challenges.

Bouferraa Y ，Chedid A ，Amhaz G ，El Lakkiss A ，Mukherji D ，Temraz S ，Shamseddine A ... -  《-》

The role of the gut microbiota in tumor, immunity, and immunotherapy.

In recent years, with the deepening understanding of the gut microbiota, it has been recognized to play a significant role in the development and progression of diseases. Particularly in gastrointestinal tumors, the gut microbiota influences tumor growth by dysbiosis, release of bacterial toxins, and modulation of host signaling pathways and immune status. Immune checkpoint inhibitors (ICIs) have greatly improved cancer treatment efficacy by enhancing immune cell responses. Current clinical and preclinical studies have demonstrated that the gut microbiota and its metabolites can enhance the effectiveness of immunotherapy. Furthermore, certain gut microbiota can serve as biomarkers for predicting immunotherapy responses. Interventions targeting the gut microbiota for the treatment of gastrointestinal diseases, especially colorectal cancer (CRC), include fecal microbiota transplantation, probiotics, prebiotics, engineered bacteria, and dietary interventions. These approaches not only improve the efficacy of ICIs but also hold promise for enhancing immunotherapy outcomes. In this review, we primarily discuss the role of the gut microbiota and its metabolites in tumors, host immunity, and immunotherapy.

Xie Y ，Liu F 《Frontiers in Immunology》

Modulation of gut microbiota to overcome resistance to immune checkpoint blockade in cancer immunotherapy.

Immune checkpoint blockade therapies that target CTLA-4 and PD-1/PD-L1 have ushered in a new era of cancer treatment. Nevertheless, a significant proportion of patients demonstrated primary or acquired resistance. Harnessing gut microbiota has been an emerging novel therapeutic strategy to overcome resistance. Here we summarized the current research status of gut microbiota in immune checkpoint blockade therapies, clinical trials, underlying mechanisms and challenges of microbiome research in checkpoint immunotherapy. Findings from preclinical models, standardized microbiome analysis and progress of multi-omic approaches may better disclose the interaction between gut microbiota and immune checkpoint inhibitors (ICIs) and traditional Chinese medicine can be a potential microbiome modulator to sensitize the response to ICIs.

Huang J ，Jiang Z ，Wang Y ，Fan X ，Cai J ，Yao X ，Liu L ，Huang J ，He J ，Xie C ，Wu Q ，Cao Y ，Leung EL ... -  《-》