When loaded into EVs secreted by human bone marrow stromal cells (hBMSCs), miR-1208 crosses the BBB, acting as a tumor suppressor by inhibiting key pathways involved in glioma progression, by negatively regulating the expression of Methyltransferase-like 3 (METTL3) and suppressing the TGF-β pathway. The gene discussed is METTL3; the disease is neoplasm.