SPP1 and hepatocellular carcinoma: Most of the genes downregulated when the CCK-BR was knocked out promote HCC proliferation such as Tmem45a (transmembrane protein 45a; 52), Spp1 (secreted phosphoprotein 1-Osteopontin; 53), Slco3a1 (solute carrier organic anion transporter; 54), and GSE1 (genetic suppressor element; 55).