DDR1 and hepatocellular carcinoma: The mRNA expression of DDR1 in SK-HEP is similar to that in the LX2 cell. Down-regulation of DDR1 decreases the phosphorylation of AKT and ERK, inhibits the expression of ICAM1, Ki67, VCAM1, and MMP9, reduces the adhesion and migration of HCC cells to collagen type I