Temporal Quantitative Proteomics Analysis of Neuroblastoma Cells Treated with Bovine Milk-Derived Extracellular Vesicles Highlights the Anti-Proliferative Properties of Milk-Derived Extracellular Vesicles.

Neuroblastoma (NBL) is a pediatric cancer that accounts for 15% of childhood cancer mortality. Amplification of the oncogene N-Myc occurs in 20% of NBL patients and is considered high risk as it correlates with aggressiveness, treatment resistance and poor prognosis. Even though the treatment strategies have improved in the recent years, the survival rate of high-risk NBL patients remain poor. Hence, it is crucial to explore new therapeutic avenues to sensitise NBL. Recently, bovine milk-derived extracellular vesicles (MEVs) have been proposed to contain anti-cancer properties. However, the impact of MEVs on NBL cells is not understood. In this study, we characterised MEVs using Western blotting, NTA and TEM. Importantly, treatment of NBL cells with MEVs decreased the proliferation and increased the sensitivity of NBL cells to doxorubicin. Temporal label-free quantitative proteomics of NBL cells highlighted the depletion of proteins involved in cell metabolism, cell growth and Wnt signalling upon treatment with MEVs. Furthermore, proteins implicated in cellular senescence and apoptosis were enriched in NBL cells treated with MEVs. For the first time, this study highlights the temporal proteomic profile that occurs in cancer cells upon MEVs treatment.