SPRED1 and fibrosarcoma: Furthermore, endothelial progenitor cell-derived exosomes are enriched in miR-126, which can target and downregulate Sprouty-related EVH1 domain-containing protein 1 (SPRED1) and activate rapidly accelerated fibrosarcoma/extracellular signal regulated kinase (RAF/ERK) signaling pathway, improve endothelial cell function, enhance endothelial cell proliferation, migration, and tubule formation, and improve LPS-induced ALI and restoring lung integrity in vivo [132,133].