Exosomal-associated miR-105 in breast cancer targets directly ZO-1 in endothelial cells [83], while regulation of ZO-1 by exosomal miR-25-3p occurs indirectly, as miR-25-3p targets KLF2 and KLF4 (Krüppel-like factors 2 and 4) in endothelial cells, regulating expression of ZO-1, VEGFR2 (vascular endothelial growth factor), occludin and claudin-5 [82]. Here, KLF2 is linked to breast carcinoma.