The role of gut mycobiome in responses to cancer immunotherapy.

The gut microbiome has emerged as an important modulator of cancer progression and therapy response, yet the role of its fungal component, the gut mycobiome, remains poorly understood. In this review, we summarize current knowledge on the relationship between intestinal fungi and cancer, with a particular focus on the potential influence of the gut mycobiome on the efficacy of immune checkpoint inhibitors (ICIs). Drawing from both human studies and preclinical models, we discuss evidence linking fungal dysbiosis to altered immune responses and therapy outcomes in cancer patients. Specific fungal taxa, such as Candida and Malassezia, have been associated with changes in the tumor microenvironment and modulation of host immunity. We also review the proposed mechanisms through which fungi may impact antitumor immunity, including interactions with immune receptors and production of bioactive metabolites. Although research in this field is still in its early stages, emerging data suggest that the gut mycobiome may serve as a biomarker for immunotherapy response and a potential target for therapeutic intervention. A better understanding of host-fungus interactions in the gut could contribute to the development of personalized strategies to improve the effectiveness and safety of cancer immunotherapy.