Breast milk exosomes: Implications for Brain function and Oncogenesis

Breast milk derived exosomes (MDEs) are small extracellular vesicles which have been capturing attention due to their role in fetal-maternal communication, mostly for their beneficial effects related to neurodevelopment during the infant's early postnatal life. Ongoing studies highlight how environmental factors, maternal nutrition and lifestyle, affect the composition of MDEs (signaling molecules, immune factors, essential nutrients, etc.), which contribute to infant immune system maturation, gastrointestinal function and brain development. Scientific evidence indicates that milk-derived exosomes can withstand digestion, enter the systemic circulation, localize in peripheral tissues and cross the blood-brain barrier (BBB). To this end, MDEs are being exploited for their bioactive cargo profile and their contribution to the regulation of neuroinflammation, stem cell differentiation, synaptic plasticity and neuronal formation. One of the main therapeutic challenges of brain tumors is their marked heterogeneity, and the unique characteristics of MDEs that renders them promising drug delivery vehicles for these tumors. Herein, we describe the latest research studies supporting the beneficial role of MDEs in brain health and cancer preclinical models, demonstrating the ability to activate apoptotic signaling pathways and promote antitumor immune responses in tumor microenvironment as well as exhibiting a promising therapeutic potential.