The overexpression of TNFSF9 and the treatment of the recombinant TNFSF9 protein can significantly inhibit the proliferation, metastasis, and invasion of hepatocellular carcinoma cells Huh7 and SMMC-7721 in vitro, and the tumor-suppressive effect of TNFSF9 was also demonstrated in vivo so that it can be used as a tumor-inhibiting factor of hepatocellular carcinoma [31]. The gene discussed is TNFSF9; the disease is hepatocellular carcinoma.