Gut microbiota in cancer cachexia: a new frontier for research and therapy

Cancer cachexia is a multifactorial syndrome characterized by systemic inflammation, progressive weight loss, muscle wasting, and metabolic alterations, which negatively affect quality of life, treatment response, and survival in cancer patients. Despite its prevalence and impact, effective treatments remain limited, in part due to the complex and poorly understood pathophysiology of the syndrome. Recent studies have revealed that gut microbiota alterations may contribute to the development and progression of cachexia through mechanisms involving immune activation, impaired gut barrier function, and disrupted metabolic signaling. This review explores the interplay between the altered gut microbiome and cancer cachexia, focusing on microbial metabolites such as short-chain fatty acids, gut barrier dysfunction and the impact of cancer therapies on microbial homeostasis. We evaluate emerging microbiota-targeted strategies, including traditional and next-generation probiotics and fecal microbiota transplantation, as novel therapeutic avenues. A deeper understanding of host–microbiome interactions may lead to the development of more effective, personalized interventions to improve cancer cachexia patient care.