TGFB1 and neoplasm: We next investigated whether inhibition of the β6 subunit in PC3 cells by +siITGB6 sEVs might affect the ability of PC3 cells to adhere and migrate on extracellular matrix proteins such as fibronectin (FN) and LAP-TGFβ1, two major ligands found in the tumor microenvironment and specific for the αVβ6 integrin.9,48 We find that upon inhibition of the β6 subunit by +siITGB6 sEVs, there is no significant change in PC3 cell adhesion and migration on FN (Figure 4c, d) compared to PC3 cells that were treated with +siNS sEVs.