The gut microbiome and dietary interventions in cancer cachexia

PURPOSE OF REVIEW: The gut microbiome (GM) is altered in cancer cachexia, and it is possible that such GM changes may promote or sustain features of cancer cachexia including changes in host metabolism and anorexia. As a result, there is growing interest in GM-focused interventions to address cancer cachexia. In this review, the factors that likely contribute to changes in GM in cancer cachexia are highlighted. Also, this review presents recent data on GM-derived predictive biomarkers for response to dietary interventions in cachexia. RECENT FINDINGS: The importance of maintaining or increasing energy intake to combat cancer cachexia has become clearer in recent years. However, there is wide inter-individual variation in response to changes after dietary interventions. Two recent studies have reported GM features which predict response to different types of dietary interventions: enteral feeding in pancreatic cancer patients, and oral nutritional counselling promoting an energy and protein dense diet in a mixed cancer group attending a specialized cancer cachexia clinic. Each study reported that increased abundance of a specific GM taxon predicted a more favourable response to the dietary intervention used. SUMMARY: GM features may prove to be important in identifying patients with cancer cachexia who are more or less likely to respond well to current dietary interventions. This has clear clinical implications and utility. Further studies will be needed to determine whether GM-targeted interventions can be developed to improve response to dietary interventions and the management of cachexia more generally.