miR-21 is highly enriched in EVs and is considered to be an oncogene, as it promotes tumor cell proliferation, migration, and invasiveness by targeting a number of tumor-suppressor genes, such as various components of the p53 network (43), PTEN (44), and antagonists of the RAS pathway PDCD4, BTG2, SPRY2, and others (45–47). Here, BTG2 is linked to neoplasm.