Because the delivery of therapeutic miRNAs through the BBB is limited, the intranasal injection of miRNA-loaded CXCR4-engineered mpEVs has been trialed in an orthotopic glioblastoma (GBM) mouse model, where the mpEVs were observed to travel through the nasal epithelia, bypass the BBB, and enter the intracranial region. The gene discussed is CXCR4; the disease is glioblastoma.