RPP21 and hepatocellular carcinoma: This study also discovered that SOF increased cell proliferation and migration in hepatoma cells with or without HCV infection, while knockdown of PHOSPHO2-KLHL23, TSNAX-DISC1, TRIM39 and RPP21 reduced the increase in cell proliferation and migration by SOF in OR-6 (HCV-positive HCC cell line) and Huh 7.5.1 (HCV-negative HCC cell line) cells.