We knocked down DDR1 in HLF and HLE cells that express high levels of DDR1 (shDDR1-2 and shDDR1-3), and overexpressed DDR1 in SK-Hep1, Hep3B, and HCC-LM3 cells with low DDR1 expression. The gene discussed is DDR1; the disease is hepatocellular carcinoma.