Anticancer Potential of Prebiotics: Targeting Estrogen Receptors and PI3K/AKT/mTOR in Breast Cancer.

Estrogen receptors (ERs) play a critical role in breast cancer (BC) development and progression, with ERα being oncogenic and ERβ exhibiting tumor-suppressive properties. The interaction between ER signaling and other molecular pathways, such as PI3K/AKT/mTOR, influences tumor growth and endocrine resistance. Emerging research highlights the role of prebiotics in modulating gut microbiota, which may influence estrogen metabolism, immune function, and therapeutic responses in BC. This review explores the impact of prebiotics on estrogen receptor modulation, gut microbiota composition, immune regulation, and metabolic pathways in breast cancer. The potential of prebiotics as adjunctive therapies to enhance treatment efficacy and mitigate chemotherapy-related side effects is discussed. A comprehensive analysis of recent preclinical and clinical studies was conducted, examining the role of prebiotics in gut microbiota modulation, immune regulation, and metabolic reprogramming in breast cancer. The impact of short-chain fatty acids (SCFAs) derived from prebiotic fermentation on epigenetic regulation and endocrine resistance was also evaluated. Prebiotics were found to modulate the gut microbiota-estrogen axis, reduce inflammation, and influence immune responses. SCFAs demonstrated selective estrogen receptor downregulation and metabolic reprogramming, suppressing tumor growth. Synbiotic interventions mitigate chemotherapy-related side effects, improving the quality of life in breast cancer patients. Prebiotics offer a promising avenue for breast cancer prevention and therapy by modulating estrogen metabolism, immune function, and metabolic pathways. Future clinical trials are needed to validate their efficacy as adjunctive treatments in breast cancer management.