Microbiome dysbiosis and its modulation in cancer development, prevention and therapy

Gut microbiome dysbiosis, a state of microbial imbalance, altered microbial function, and disturbed homeostasis between the gut microbiome and its host, is increasingly recognized as a key contributor to cancer development, progression, and variability in therapeutic response. These microbiome states can facilitate cancer development through chronic inflammation, expansion of microbial genotoxin producers, or disturbances of immune defense mechanisms. In this review, we will discuss current findings on gut microbiome dysbiosis in cancer initiation and progression, emphasizing mechanisms that links dysbiosis to oncogenic transformation and tumor microenvironment remodeling. Furthermore, we will explore microbiome-targeting strategies for cancer prevention and therapeutic support, including dietary modulation, probiotics, prebiotics, and fecal microbiota transplantation. These various microbiome modulations have shown promise in restoring microbial homeostasis, enhancing immunotherapy efficacy, and reducing treatment-associated toxicity. Advances in microbial genomics and metabolomics further enable the identification of biomarkers for predicting cancer risk and therapeutic outcomes. Despite significant progress, translation into clinical settings faces challenges related to interindividual variability, standardization, and mechanistic complexity. Understanding the microbiome-cancer interface provides a platform for personalized, microbiome-informed oncology, paving the way for prevention-driven and precision-guided therapeutics.