PTK2 and hepatocellular carcinoma: Only downregulation of Solute Carrier Family 45 Member 4 (SLC45A4), Protein Tyrosine Kinase 2 (PTK2), DENN Domain Containing 3 (DENND3), and Trafficking Protein Particle Complex 9 (TRAPPC9) was associated with a dose-dependent decrease in both ASTILCS expression and HCC cell survival (Fig. 4B, see also Fig. 3A, B).