NCAM1 and mantle cell lymphoma: After exosomes were sorted by the aforementioned exosomal markers, the surface expression of CD20, which is a marker for B-cells, showed enrichment of CD20-positive exosomes in the serum of patients with DLBCL, FL, and MCL, whereas exosomes derived from ENKTL patients showed CD56 expression, a marker for NK-cells (Figure 1F).