MMP9 and hepatocellular carcinoma: Our previous studies have demonstrated that HAb18G/CD147 stimulates fibroblast cells to produce elevated levels of several MMPs, including MMP-1, MMP-2, and MMP-9, which are well known for prompting invasion of hepatocellular carcinoma (HCC) cells and antisense RNA of HAb18G/CD147 inhibited the invasion of HCC cells in vitro [9].