DPP4 and hepatocellular carcinoma: Similar results were obtained after 1F7 treatment of Jurkat/CD26 cells (Fig. S2A), and after YS110 treatment of Li7 hepatocellular carcinoma cells that expressed CD26 exogenously (Fig. S2B), suggesting that YS110 and 1F7 induced nuclear translocation of CD26 in cancer cells.