The Gut Microbiome Composition and the Efficacy of Response to Immunotherapy of NSCLC

Abstract

In recent years, immune checkpoint inhibitors (ICIs) have been successfully used in advanced non-small cell lung carcinoma (NSCLC) treatment, bringing a wider range of options to patients. Nonetheless, questions still remain, as a high prevalence of primary and secondary resistances to immunotherapy are a known problem. In this review, we tried summarizing the current understanding, in 2023, aiming to address and describe the relationship between the composition of the human gut microbiota and response to NSCLC immunotherapy using ICIs. We found that the gut microbiota indeed influences response to ICIs, with both short-chain fatty acid and lactic acid producing commensals seeming to be both the most common and capable of influencing responses, although with varying and somewhat opposing results. With such an inconclusive influence, either promoting or hindering response, further research is necessary in order to understand why and in what contexts these metabolites induce the effects they do.