To validate that miR-19 family miRNAs play an important role in invasion, we utilized antagomirs–short oligonucleotides that bind and inactivate miRNAs–to specifically knock down miR-19 function in KPC lines with high invasive capacity and varying levels of miR-19 expression . We first confirmed miR-19 antagomir activity using a β-galactosidase (β-Gal) reporter containing multiple miR-19 binding sites within the 3′UTR that allow translational suppression in the presence of miR-19. Pooled antagomirs against miR-19a and miR-19b enhanced reporter activity in a KPC cell line, but not in a 17KPC cell line (Supplementary Figure 9).